Stem eccentricity, crown dry mass distribution, and longitudinal growth strain of plantation-grown Eucalyptus nitens after thinning

2011 ◽  
Vol 41 (11) ◽  
pp. 2209-2218 ◽  
Author(s):  
Jane Medhurst ◽  
Maria Ottenschlaeger ◽  
Matthew Wood ◽  
Chris Harwood ◽  
Chris Beadle ◽  
...  
Keyword(s):  
Mass Distribution ◽  
Dry Mass ◽  
Solid Wood ◽  
Wood Products ◽  
Eucalyptus Nitens ◽  
Cross Sectional ◽  
The North ◽  
Silvicultural Treatments ◽  
Wind Exposure ◽  
Pith Eccentricity

Silvicultural treatments that aim to improve tree growth rates also have the potential to alter physical characteristics of the tree stem and thus affect the recovery of solid-wood products. We tested the hypothesis that manifest crown asymmetry in thinned Eucalyptus nitens (Deane & Maiden) Maiden plantations was affecting the development of stem shape. The crown and stem characteristics of 15 E. nitens trees from a 22-year-old thinning trial in northeastern Tasmania were examined. The trial had been thinned 16 years previously. Lowering the intensity of local intraspecific competition through thinning increased the crown dry mass in the north-facing aspect. No direct link was found between crown dry mass distribution and stem eccentricity. The direction of pith eccentricity at 3.0 m height was confined to the northwest and southeast sectors and averaged 11%; the degree of noncircularity in stems at 3.0 m height was strongly related to the ratio of stem diameter to total height squared. These results suggest that the dynamic loading from wind exposure plays a greater role in determining the extent and direction of pith eccentricity and stem cross-sectional circularity in E. nitens than does the static load from asymmetrical crown dry mass distribution.

Radio frequency vacuum drying of Eucalyptus nitens juvenile wood

BioResources ◽  
2020 ◽  
Vol 15 (3) ◽  
pp. 4886-4897
Author(s):  
Rubén A. Ananías ◽  
Víctor Sepúlveda-Villarroel ◽  
Natalia Pérez-Peña ◽  
José Torres-Mella ◽  
Linette Salvo-Sepúlveda ◽  
...  
Keyword(s):  
Radio Frequency ◽  
Juvenile Wood ◽  
Wood Quality ◽  
Solid Wood ◽  
Wood Products ◽  
Eucalyptus Nitens ◽  
Drying Time ◽  
Innovative Products ◽  
Conventional Kiln Drying ◽  
Vacuum Method

Wood drying is an important process for adding value and manufacturing innovative products. Eucalyptus nitens wood is inherently difficult to dry because of its natural propensity for checking as well as collapse and shrinkage. Lumber recovery after industrial drying of eucalypts is also very low. This study measured the wood quality of E. nitens juvenile wood (13 mm thickness) after radio-frequency vacuum (RFV) drying and wood dried in a conventional kiln dryer (KD). Drying cycles were performed using a radio frequency vacuum dryer with a 3 m3 of capacity and convective kiln-dryer equipment with a 3.5 m3 of capacity. The results showed that the drying time using the radio frequency vacuum method was reduced by 47% when compared to conventional kiln drying. The shrinkage was significantly lower in the RFV than in the conventional KD. The volumetric collapse decreased by approximately 60% in the RFV drying. RFV drying of E. nitens juvenile wood improves the wood quality for solid wood products because the intensity of surface checking and collapse are reduced.

scholarly journals The effect of time and site on incidence and spread of pruning-related decay in plantation-grown Eucalyptus nitens

2005 ◽  
Vol 35 (3) ◽  
pp. 495-502 ◽  
Author(s):  
Karen M Barry ◽  
Malcolm F Hall ◽  
Caroline L Mohammed
Keyword(s):  
Quantitative Information ◽  
Solid Wood ◽  
Fungal Species ◽  
Wood Products ◽  
Eucalyptus Nitens ◽  
Ongoing Research ◽  
Yield And Quality ◽  
Eucalypt Plantations ◽  
The Future ◽  
Over Time

Quantitative information on stem decay in eucalypt plantations grown for solid wood products, with consideration of the effect of site, pruning, and spread of decay with time, is required for the prediction of harvest yield and quality. A trial at three Eucalyptus nitens (Dean & Maiden) Maiden plantations in Tasmania revealed that the effect of time on the number and size of decay columns was substantially greater than the effect of site or of whether trees were pruned or not. Length of decay columns was 3.4-fold greater on average for the trees assessed 5.5 years after pruning than at 1 year. All decay columns in pruned trees were restricted to the knotty core, and the amount of decay-free clearwood increased over time. A controlled wounding trial showed that decay in sapwood was not significantly different in length with site but was mainly determined by the fungal species used. Ongoing research to monitor the spread of decay in pruned plantation-grown E. nitens will be important to enable prediction of the future impact of decay on harvest yields of solid wood products.

scholarly journals Genetic variation of microfibril angle and its relationship with solid wood and pulpwood traits in two progeny trials of Eucalyptus nitens in Tasmania

Holzforschung ◽  
2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Manuel F. Rocha-Sepúlveda ◽  
Dean Williams ◽  
Mario Vega ◽  
Peter A. Harrison ◽  
René E. Vaillancourt ◽  
...  
Keyword(s):  
Genetic Correlations ◽  
Microfibril Angle ◽  
Basic Density ◽  
Genotype By Environment Interaction ◽  
Solid Wood ◽  
Wood Products ◽  
Pulp Yield ◽  
Environment Interaction ◽  
Eucalyptus Nitens ◽  
Genotype By Environment

Abstract Microfibril angle (MFA) is a key biological trait contributing to wood stiffness, which is a common breeding objective for solid wood products in many tree species. To explore its genetic architecture, area-weighted MFA was measured in two Eucalyptus nitens progeny trials in Tasmania, Australia, with common open-pollinated families. Radial strips were extracted from 823 trees in 131 families and MFA assessed using SilviScan-2®. Heritability, genotype-by-environment interaction and inter-trait genetic correlations were evaluated to examine the genetic variability and stability of MFA and its relationships with other solid wood and pulpwood selection traits. Significant family variation was found for MFA in both trials. There was no significant genotype-by-environment interaction and the across-site narrow-sense heritability was 0.27. MFA was genetically independent of basic density, growth, and tree form. However, MFA was strongly and favourable genetically correlated to acoustic wave velocity in standing trees, modulus of elasticity and kraft pulp yield (KPY). The present study has shown that genetic improvement of E. nitens for pulpwood selection traits is unlikely to have adversely affected MFA, and thus timber stiffness. Rather these results suggest the possibility that selection for increased KPY may have indirectly improved MFA favourably for solid wood products.

Drying of Eucalyptus nitens for solid wood products

Impact ◽  
2018 ◽  
Vol 2018 (6) ◽  
pp. 43-44
Author(s):  
Rub,n A. ANANIAS
Keyword(s):  
Solid Wood ◽  
Wood Products ◽  
Eucalyptus Nitens

scholarly journals Physico-mechanical properties of thermally modified Eucalyptus nitens wood for decking applications

2019 ◽  
Vol 70 (3) ◽  
pp. 235-245 ◽  
Author(s):  
Maximilian Wentzel ◽  
Óscar González-Prieto ◽  
Christian Brischke ◽  
Holger Militz
Keyword(s):  
Brinell Hardness ◽  
Good Alternative ◽  
Solid Wood ◽  
Thermal Modification ◽  
Wood Products ◽  
Added Value ◽  
Eucalyptus Nitens ◽  
Plantation Species ◽  
The Moment ◽  
Quality Material

Eucalyptus nitens is a fast growing plantation species that has a good acclimation in Spain and Chile. At the moment it is mainly used for pulp and paper production, but there is a growing market for solid wood products made from this species. Thermal modification offers a good alternative to produce high quality material to manufacture products with high added value. This study used unmodified and thermally modified E. nitens wood from Spanish and Chilean plantations to elaborate external decking and examine if it complies with the necessary properties to be a competitive product. A process similar to ThermoWood® was applied at the following temperatures: 185 °C, 200 °C and 215 °C. For each modification and for an unmodified specimen mass loss, volumetric swelling, anti-swelling efficiency (ASE) and equilibrium moisture content (EMC) were determined. Brinell hardness, dynamic hardness, screw and nail withdrawal resistance, and abrasion resistance according to the Shaker method and the Taber Abraser method were also determined. According to this study, thermally modified E. nitens from both countries showed high potential to be used as decking material, particularly when modified at 200 °C.

ANALISIS HUBUNGAN SARANA, PENGETAHUAN, DAN SIKAP BIDAN PRAKTIK MANDIRI DENGAN KEPATUHAN MENJALANKAN STANDAR PELAYANAN ANTENATAL CARE DI KOTA PADANGSIDIMPUAN

2019 ◽  
Vol 2 (1) ◽  
pp. 27-33
Author(s):  
Megawati Sinambela ◽  
Evi Erianty Hasibuan
Keyword(s):  
Logistic Regression ◽  
Regression Analysis ◽  
Antenatal Care ◽  
Pregnant Women ◽  
Logistic Regression Analysis ◽  
Care Service ◽  
Multivariate Logistic Regression Analysis ◽  
Bivariate Analysis ◽  
Cross Sectional ◽  
The North

Antenatal care is a service provided to pregnant women to monitor, support maternal health and detect mothers whether normal or problematic pregnant women. According to the WHO, globally more than 70% of maternal deaths are caused by complications of pregnancy and childbirth such as hemorrhage, hypertension, sepsis, and abortion. Based on data obtained from the profile of the North Sumatra provincial health office in 2017, in the city of Padangsidimpuan in 2017 the coverage of ANC visits reached (76.58%) and had not reached the target in accordance with the 2017 Provincial Health Office strategy plan (95%). This type of research was an observational analytic study with a cross sectional design. The population in this study were independent practice midwives who were in the Padangsidimpuan, the sample in this study amounted to 102 respondents. The technique of collecting data used questionnaires and data analysis used univariate, bivariate and multivariate analysis with logistic regression analysis. Based on bivariate analysis showed that there was a relationship between facilities, knowledge and attitudes of independent midwives with compliance with the standards of antenatal care services with a value of p <0.05. The results of the study with multivariate logistic regression analysis showed that the factors associated with the compliance of independent midwives in carrying out antenatal care service standards were attitudes with values (p = 0.026).

scholarly journals Retrospective study of the distribution of doctors in municipalities of extreme poverty in Brazil

2020 ◽  
Vol 30 (Supplement_5) ◽  
Author(s):  
B L O Luizeti ◽  
E M M Massuda ◽  
L F G Garcia
Keyword(s):  
Public Health ◽  
Health System ◽  
Cross Sectional Study ◽  
Cross Sectional ◽  
Extreme Poverty ◽  
The Public ◽  
The North ◽  
Unified Health System ◽  
Shortage Of Doctors ◽  
Demographic Distribution

Abstract In view of the national scenario of scarcity of material and human resources in public health in Brazil, the survey verified the demographics of doctors who attend the Unified Health System (SUS) in municipalities of extreme poverty. An observational, analytical and cross-sectional study was carried out, based on secondary quantitative data from the Department of Informatics of the SUS using the TABNET of December 2019. The care networks variable was restricted to infer the number of physicians who attend the SUS in extreme poverty municipalities in Brazil. Municipalities of extreme poverty are those that at least 20% of the population have a household income of up to 145 reais per capita monthly. In Brazil, there are 1526 municipalities in extreme poverty, 27.4% of the country's total municipalities. 14,907 doctors linked to SUS work in this condition, 3.19% of the total of these professionals in Brazil. There is still disproportion between regions: North concentrates 11.2% of the municipalities in extreme poverty and 8.61% of the total number of doctors; Northeast, with 61.33% of these municipalities, for 61.5% of doctors; Southeast, with 15.46% of the municipalities in this condition, has 20.6% of doctors; South concentrates 10.87% of the municipalities under discussion with 5.61% of doctors and the Midwest, with 4.87% of these municipalities, has 3.54% of doctors. Between 2009 and 2018, there was a 39% increase in the number of doctors in these locations, however, for 2019, there was a decrease of 3.89%. The medical demographic distribution in Brazil is uneven, especially in the North. There is also the vulnerability of this population in view of the observed reduction in the number of professionals between 2018 and 2019 in municipalities of extreme poverty, for political reasons. It is evident the need to restructure the health system to guarantee access to health for this population, through the attraction and fixation of doctors in needy regions in Brazil. Key messages Shortage of doctors in extreme poverty municipalities reinforces the health vulnerability of the population in Brazil. The uneven medical demography in Brazil requires restructuring in the public health system.

Chain of custody certification: an assessment of the North American solid wood sector

2005 ◽  
Vol 7 (3) ◽  
pp. 345-355 ◽  
Author(s):  
Natalia Vidal ◽  
Robert Kozak ◽  
David Cohen
Keyword(s):  
North American ◽  
Solid Wood ◽  
The North ◽  
Chain Of Custody ◽  
Wood Sector
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