Formation and vertical distribution of juvenile and mature wood in a single stem of Cryptomeriajaponica

1994 ◽  
Vol 24 (5) ◽  
pp. 969-975 ◽  
Author(s):  
K.C. Yang ◽  
Y.S. Chen ◽  
C. Chiu
Keyword(s):  
Vertical Distribution ◽  
Juvenile Wood ◽  
Wood Formation ◽  
Mature Wood ◽  
Regression Methods ◽  
Sample Tree ◽  
Significant Difference ◽  
Two Measures ◽  
Highly Correlated ◽  
The Impact

A single tree stem was used to study the formation and vertical distribution of juvenile and mature wood in Cryptomeriajaponica D. Don. The sample tree was collected from a 45-year-old plantation with 1.5 × 3.0 m spacing at Maio-li, Taiwan. Nine diametric wood strips were cut from the tree trunk from both the east and the west aspects, starting from 0.3 m by increments of 2.5 m to the top of the tree. The widths of juvenile and mature wood were recorded with two measures, i.e., the number of rings and the width in millimetres. The relationships between both the width of juvenile and mature wood and the height and age at each level of the tree were obtained by regression methods. The relationships between the age of the cambial initial and the period of juvenile wood formation at the various height levels were also determined. It was found that juvenile wood has a conical shape with a wide base at the bottom of the tree. There is no significant difference in the ratio of juvenile to mature wood width between the east and west aspects of the tree. The impact of both the height and age at each level of the tree on the width of juvenile wood appears to differ, and a similar observation must be made for mature wood. A high proportion of the total wood volume (64%) was found to be juvenile wood. No mature wood was observed at the top of the tree. The width of juvenile wood is highly correlated with the age of formation of cambial initials counted from the year of seed germination. The older the cambial initial, the narrower is the width of juvenile wood in terms of ring count.

Impact of spacing on tracheid length, relative density, and growth rate of juvenile wood and mature wood in Piceamariana

1994 ◽  
Vol 24 (5) ◽  
pp. 996-1007 ◽  
Author(s):  
K.C. Yang ◽  
G. Hazenberg
Keyword(s):  
Growth Rate ◽  
Relative Density ◽  
Boundary Point ◽  
Juvenile Wood ◽  
The Other ◽  
Mature Wood ◽  
Average Growth ◽  
Tracheid Length ◽  
Significant Difference ◽  
The Impact

Ten 38-year-old trees of Piceamariana (Mill.) B.S.P., grown at each of three spacings (1.8 × 1.8, 2.7 × 2.7, and 3.6 × 3.6 m), at Stanley, 30 km west of Thunder Bay, Ont., were used to study the impact of spacing on growth rate, relative density, and tracheid length of juvenile and mature wood. Increment cores of 12 mm diameter were extracted from the south aspect of each tree at breast height. The boundary of juvenile and mature wood was demarcated by the variation in tracheid length, which varied among trees from ring 11 to 21. Average growth rate, relative density, and tracheid length were obtained between the pith and boundary point (juvenile wood) and beyond the boundary point (mature wood). Differences between the levels of spacing for the three response variables in both juvenile and mature wood were tested using contrasts. Properties of juvenile and mature wood were found to be affected differently by the plantation spacing. Juvenile wood has a faster growth rate and shorter fibres than mature wood. Relative density was similar in both wood zones. The growth rate in juvenile wood was found to be significantly different among the spacing levels. For mature wood, only the growth rate at the 3.6 × 3.6 m spacing was significantly different from the other two spacing levels. The highest relative density, 0.39, in both juvenile and mature wood was found at the 1.8 × 1.8 m spacing. No significant difference in the relative density between the two wider spacings was observed. At the widest spacing, the relative density was 8% lower than that at the 1.8 × 1.8 m spacing. The longest fibre lengths were found at the intermediate 2.7 × 2.7 m spacing, 2.05 mm in juvenile wood and 2.94 mm in mature wood. Tracheid lengths of the 3.6 × 3.6 m spacing were significantly shorter than those of the other two spacings. The relative density and tracheid length of plantation grown wood were lower than those of natural grown wood by at least 5% for relative density and 33% for tracheid length.

scholarly journals Influence of juvenile and mature wood on anatomical and chemical properties of early and late wood from Chinese fir plantation

2021 ◽  
Vol 67 (1) ◽  
Author(s):  
Changqing Lu ◽  
Jun Wu ◽  
Qianqian Jiang ◽  
Yamei Liu ◽  
Liang Zhou ◽  
...  
Keyword(s):  
Juvenile Wood ◽  
Lignin Content ◽  
Microfibril Angle ◽  
Chemical Properties ◽  
Decisive Role ◽  
Chinese Fir ◽  
Mature Wood ◽  
Chemical Components ◽  
Late Wood ◽  
Significant Difference

AbstractThe proportion of juvenile wood affects the utilization of wood seriously, and the transition year of juvenile wood (JW) and mature wood (MW) plays a decisive role in the rotation and the modification of wood. To find out the demarcation of JW and MW, the tracheid length (TL) and microfibril angle (MFA) of early wood (EW) and late wood (LW) from four Chinese fir clones were measured by optical microscopy and X-ray diffraction. Then the data were analyzed by the k-means clustering method. The correlation and the differences among wood properties between JW and MW were compared. Results indicated that the LW showed better properties than that of EW, but the anatomical differences between EW and LW did not influence the demarcation of JW and MW. The cluster analysis of TL and MFA showed that the transition year was in the 16th year and the transition zone of EW and LW was different among clones. The MW has longer and wider tracheid, thicker cell walls, and smaller MFA. In terms of chemistry, MW had a higher content of holocellulose, α-cellulose, less content of extract, but no significant difference in lignin content compared with JW. The stabilization of chemical components was earlier than that of the anatomic properties. Correlation analysis showed that there were strong correlations between the chemical composition and anatomical characteristics in JW and MW. In general, compared with chemical components, anatomical indicators were more suitable for JW and MW demarcation. The differences and correlations between JW and MW properties provide a theoretical basis for wood rotation and planting.

Indentation of Juvenile Annual Growth Rings and their Impact on Morphology of Wood Cells

2016 ◽  
Vol 688 ◽  
pp. 175-181 ◽  
Author(s):  
Vladimír Racko ◽  
Olga Misikova ◽  
Igor Cunderlik ◽  
Blazej Seman
Keyword(s):  
Juvenile Wood ◽  
Growth Ring ◽  
Small Diameter ◽  
Normal Growth ◽  
Growth Rings ◽  
Annual Growth Rings ◽  
Significant Difference ◽  
Parenchyma Cells ◽  
The Impact ◽  
Quality Production

The morphology of cellular elements of juvenile wood of spruce has, in comparing to mature wood, different parameters. Subsequently, indented growth ring zones, caused by genetic predisposition and cambial injury, can significantly change the morphology of these tissues. The aim of the paper compared the morphology of cellular elements of juvenile wood originating in the indented and the normal growth rings. The results confirmed a significant difference in the proportion, the dimensions and shape of parenchyma cells and tracheids. While, in zones containing the indented growth rings the proportions were 15.6 % and 84.4 %, in normal growth rings were 10.4 % and 89.6 %. Tracheids in the indented growth ring zones were shorter and narrower (1.47 mm and 25.4 µm), but in normal growth ring zones longer and wider (2.14 mm and 28.3 µm). Tracheids from marginal and central zones normal growth rings showed considerable inhomogeneity in longitudinal shape (they were twisted). On the basis of change tissue morphology in the juvenile growth phase we can expect the impact of these growth disproportions on the quality production of pulp and paper, mainly in assortments with small diameter.

scholarly journals The relation between the microscopic structure and the wood density of European beech (Fagus sylvatica L.)

2008 ◽  
Vol 54 (No. 4) ◽  
pp. 170-175 ◽  
Author(s):  
V. Gryc ◽  
H. Vavrčík ◽  
M. Rybníček ◽  
E. Přemyslovská
Keyword(s):  
Comparative Analysis ◽  
Wood Density ◽  
Juvenile Wood ◽  
European Beech ◽  
Vessel Diameter ◽  
The Other ◽  
Mature Wood ◽  
Microscopic Structure ◽  
Significant Difference ◽  
The Difference

The aim of this study was to compare the structure of beech juvenile and mature wood in relation to wood density. The comparative analysis between juvenile and mature wood examined the diameter of vessels, the width and height of pith rays, and the number of vessels and pith rays per 1 mm<sup>2</sup>. The results show that the average vessel diameter as well as the width and height of pith rays reach statistically lower values in juvenile wood than in mature wood. On the other hand, no significant difference between the two types of wood has been found in terms of the frequency of vessels per 1 mm<sup>2</sup>. Having said that, the difference in the frequency of rays per 1 mm<sup>2</sup> between juvenile and mature wood is far from being negligible; juvenile wood has three times as many pith rays as mature wood. The density of juvenile wood is higher (&rho;<sub>12</sub> = 726.07 kg/m<sup>3)</sup> than the density of mature wood ((&rho;<sub>12</sub> = 701.50 kg/m<sup>3</sup>).

scholarly journals Effect of growth rate on the physical and mechanical properties of Douglas-fir in western Europe

2017 ◽  
Vol 47 (8) ◽  
pp. 1056-1065 ◽  
Author(s):  
C. Pollet ◽  
J.-M. Henin ◽  
J. Hébert ◽  
B. Jourez
Keyword(s):  
Mechanical Properties ◽  
Growth Rate ◽  
Management Practices ◽  
Juvenile Wood ◽  
Ring Width ◽  
Physical And Mechanical Properties ◽  
Douglas Fir ◽  
Mature Wood ◽  
Cambial Age ◽  
The Impact

To quantify the impact of forest management practices and tree growth rate on the potential uses of Douglas-fir wood, nine physico-mechanical properties were studied on more than 1250 standardized clear specimens. These were collected from trees cut in 11 even-aged stands (six trees per stand) located in Wallonia (southern Belgium). Stands were 40 to 69 years old, and mean tree girth was ca. 150 cm. Mean ring width of the 66 trees ranged from 3 to more than 7 mm. Statistical analysis showed significant but weak effects of ring width on the studied properties. Considered jointly, mean ring width and cambial age of the test specimens only explained 28% to 40% of the variability of their properties. Also, when ring width increases, these properties display higher decreases in juvenile wood than in mature wood. From a technological standpoint, maintaining mean ring width under 4 mm in juvenile wood and 6 mm in mature wood should accommodate all potential uses of Douglas-fir wood. However, considering that density appeared to be the main driver of wood properties, our results and the literature corroborate the importance of genetic selection as a complement to silvicultural measures to improve or guarantee the technological properties of Douglas-fir wood.

Measuring Impact of Stress in Sandwich Generation Caring for Demented Parents

GeroPsych ◽  
2014 ◽  
Vol 27 (4) ◽  
pp. 171-179 ◽  
Author(s):  
Laurence M. Solberg ◽  
Lauren B. Solberg ◽  
Emily N. Peterson
Keyword(s):  
Factor Analysis ◽  
Exploratory Factor Analysis ◽  
Social Worker ◽  
Resource Availability ◽  
Well Being ◽  
Sandwich Generation ◽  
Item Questionnaire ◽  
Significant Difference ◽  
Adult Caregivers ◽  
The Impact

Stress in caregivers may affect the healthcare recipients receive. We examined the impact of stress experienced by 45 adult caregivers of their elderly demented parents. The participants completed a 32-item questionnaire about the impact of experienced stress. The questionnaire also asked about interventions that might help to reduce the impact of stress. After exploratory factor analysis, we reduced the 32-item questionnaire to 13 items. Results indicated that caregivers experienced stress, anxiety, and sadness. Also, emotional, but not financial or professional, well-being was significantly impacted. There was no significant difference between the impact of caregiver stress on members from the sandwich generation and those from the nonsandwich generation. Meeting with a social worker for resource availability was identified most frequently as a potentially helpful intervention for coping with the impact of stress.

Detection of Circulating Tissue Factor and Factor VII in a Normal Population

1996 ◽  
Vol 75 (05) ◽  
pp. 772-777 ◽  
Author(s):  
Sybille Albrecht ◽  
Matthias Kotzsch ◽  
Gabriele Siegert ◽  
Thomas Luther ◽  
Heinz Großmann ◽  
...  
Keyword(s):  
Tissue Factor ◽  
Normal Population ◽  
Mean Value ◽  
Factor Vii ◽  
Significant Difference ◽  
Age Dependent ◽  
The Mean ◽  
Highly Correlated ◽  
And Gender

SummaryThe plasma tissue factor (TF) concentration was correlated to factor VII concentration (FVIIag) and factor VII activity (FVIIc) in 498 healthy volunteers ranging in age from 17 to 64 years. Immunoassays using monoclonal antibodies (mAbs) were developed for the determination of TF and FVIIag in plasma. The mAbs and the test systems were characterized. The mean value of the TF concentration was 172 ± 135 pg/ml. TF showed no age- and gender-related differences. For the total population, FVIIc, determined by a clotting test, was 110 ± 15% and the factor VIlag was 0.77 ± 0.19 μg/ml. FVII activity was significantly increased with age, whereas the concentration demonstrated no correlation to age in this population. FVII concentration is highly correlated with the activity as measured by clotting assay using rabbit thromboplastin. The ratio between FVIIc and FVIIag was not age-dependent, but demonstrated a significant difference between men and women. Between TF and FVII we could not detect a correlation.

Implicit and explicit corrective feedback and feedback exposure conditions

2020 ◽  
Vol 4 (1) ◽  
pp. 3-48
Author(s):  
Takehiro Iizuka ◽  
Kimi Nakatsukasa
Keyword(s):  
Explicit Knowledge ◽  
Corrective Feedback ◽  
Significant Difference ◽  
Oral Corrective Feedback ◽  
Post Test ◽  
Picture Description ◽  
Potential Factors ◽  
Implicit And Explicit ◽  
Instructional Settings ◽  
The Impact

This exploratory study examined the impact of implicit and explicit oral corrective feedback (CF) on the development of implicit and explicit knowledge of Japanese locative particles (activity de, movement ni and location ni) for those who directly received CF and those who observed CF in the classroom. Thirty-six college students in a beginning Japanese language course received either recast (implicit), metalinguistic (explicit) or no feedback during an information-gap picture description activity, and completed a timed picture description test (implicit knowledge) and an untimed grammaticality judgement test (explicit knowledge) in a pre-test, immediate post-test and delayed post-test. The results showed that overall there was no significant difference between CF types, and that CF benefited direct and indirect recipients similarly. Potential factors that might influence the effectiveness of CF, such as instructional settings, complexity of target structures and pedagogy styles, are discussed.

Reducing the Social Stigma Associated with Obsessive Compulsive Disorder: A Controlled Trial of an Intervention Program in a Turkish Community Sample

2020 ◽  
Vol 20 (2) ◽  
pp. 101-120
Author(s):  
Ayça Aktaç Gürbüz ◽  
Orçun YORULMAZ ◽  
Gülşah DURNA
Keyword(s):  
Obsessive Compulsive Disorder ◽  
Intervention Program ◽  
Controlled Trial ◽  
Community Sample ◽  
Case Vignette ◽  
Control Group ◽  
Obsessive Compulsive ◽  
Compulsive Disorder ◽  
Significant Difference ◽  
The Impact

Scientific research into the reduction of stigmatization, particularly related to specific problems such as Obsessive-Compulsive Disorder (OCD), is scarce. In the present study, we examine the impact of a video-based antistigma intervention program for OCD in a pretest-posttest control group research. After being randomly assigned to either an intervention (n= 101) or control group (n= 96), the participants reported their attitudes on a hypothetical case vignette before and after OCD vs. Multiple Sclerosis (MS) videos, and again six months later as a follow up assessment. The mixed design analyses for the group comparisons indicated that although there was no significant difference in the measures of the control group, the participants watching the anti-stigma OCD video, in which the focus was psychoeducation and interaction strategies, reported significantly lower scores on social distances and negative beliefs for the case vignettes they read, and this difference was maintained six months later. Then, the present results indicate the effectiveness of our anti-stigma intervention program for OCD. Interventions to reduce stigmatization can also be viewed as effective tools for changing the attitudes of people toward OCD, although further research and applications are needed related to specific disorders if a longlasting impact is to be achieved.

Antecedents And Outcomes Of Qwl Among Employees In Banks

2019 ◽  
Vol 118 (7) ◽  
pp. 1-19
Author(s):  
Geethanjali N ◽  
Parveen Roja M ◽  
Lavanya D
Keyword(s):  
Organizational Climate ◽  
Job Stress ◽  
Work Life ◽  
Working Environment ◽  
Quality Of Work Life ◽  
Quality Of Work ◽  
Significant Difference ◽  
Service Productivity ◽  
The Impact

Quality of work life is the major factor to be considered in working environment of any organization. The performance of employees and the organization lies on the ability of the employees based on working environment. The QWL leads to better working environment which improves the performance of organization. The present study has made an attempt to find the level of factors causing QWL and the impact of outcome of QWL in banks. Since the profile of the banks may be associated with the level of outcomes of QWL, the present study has made an attempt to examine it with the help of one way analysis of variance and t-test. The included outcomes of QWL are job satisfaction, job stress, organizational climate, organizational commitment, employees retention behaviour, service quality employees and service productivity of employees. The highly associated determinants of QWL and the significant difference among the PUSBs and PRSBs have been noticed. The significantly associating important profiles of the banks regarding the existence of outcome of QWL are identified.

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