Stem growth responses of declining mature Abiesamabilis trees after tephra deposition from Mount St. Helens

1995 ◽  
Vol 25 (9) ◽  
pp. 1493-1502 ◽  
Author(s):  
Gerardo Segura ◽  
Thomas M. Hinckley ◽  
Chadwick D. Oliver
Keyword(s):  
Radial Growth ◽  
Stem Growth ◽  
Silver Fir ◽  
Growth Responses ◽  
Stem Analysis ◽  
Cross Sectional ◽  
Breast Height ◽  
Per Se ◽  
Mount St Helens

Stem analysis of mature Abiesamabilis (Dougl.) Forbes (Pacific silver fir) trees was used to analyze patterns of radial growth in areas of southwestern Washington where this species is experiencing a severe crown decline associated with heavy tephra deposition from the 1980 eruption of Mount St. Helens. Reductions in stem growth after 1980 appeared to be related to the severity of crown damage. The largest reductions in cross-sectional area increment exceeded 50% and extended along most of the stem. An increase in stem growth in the upper crown was common among declining trees. This zone coincided with a portion of the crown that has experienced vigorous and rapid growth since 1980. The role of this recovery zone on subsequent tree recovery is discussed. Decline or recovery of trees appeared independent of crown class per se. Reductions in radial growth of declining trees tended to be more pronounced at breast height, suggesting that estimations of whole-stem growth based on breast height measurements would overestimate growth losses.

Syllepsis in Larixlaricina: association of sylleptic branching with cross-sectional stem growth and stem form of saplings

1987 ◽  
Vol 17 (12) ◽  
pp. 1609-1619 ◽  
Author(s):  
W. D. McCurdy ◽  
G. R. Powell
Keyword(s):  
Growth Increment ◽  
Stem Growth ◽  
Main Stem ◽  
Stem Form ◽  
Cross Sectional ◽  
Long Shoots ◽  
Plus Tree ◽  
Stem Development ◽  
Lateral Branches

The effect of sylleptic branching on past stem growth of 8-year-old Larixlaricina (Du Roi) K. Koch saplings was investigated in relation to the lengths of long shoots borne on sylleptically and proleptically originated lateral branches over a 4-year period. Over time, the sylleptic crown component accounted for increasing proportions of the total crowns of saplings exhibiting syllepsis. The total length of all long shoots in the crown increased linearly from lightly to heavily sylleptic saplings. However, groups of branches of sylleptic origin declined in average shoot vigour more rapidly than did groups of branches of proleptic origin in the same height-growth increment. Annual wood ring production and total stem cross-sectional areas at various positions along the main stem were positively correlated with the proleptic, sylleptic, and total branching components occurring above those positions. Wood production along the stem was greater, more uniform and the resultant stem more conical in heavily sylleptic saplings than in lightly sylleptic saplings. The role of syllepsis in crown and main stem development was discussed in relation to plus-tree selection for tree improvement purposes.

Growth and development of sugar maple as revealed by stem analysis

1977 ◽  
Vol 7 (3) ◽  
pp. 526-536 ◽  
Author(s):  
D. C. F. Fayle ◽  
G. B. MacDonald
Keyword(s):  
Growth And Development ◽  
Radial Growth ◽  
Sugar Maple ◽  
Ring Width ◽  
Radial Increment ◽  
Light Conditions ◽  
Growth Layer ◽  
Stem Analysis ◽  
Breast Height ◽  
Crown Characteristics

Patterns of annual height and radial growth over a 50- to 60-year period are discussed for three 16- to 18-m-tall sugar maple (Acersaccharum Marsh.) of intermediate crown position growing in tolerant hardwood forest in central Ontario. Two of the trees had been released when they were about 6 m tall. Changes in the growth layer profile as the trees developed showed similarities to those reported for conifers but were modified by light conditions and crown characteristics. A repetitive pattern of changes in height and radial increment in response to changing environmental conditions occurred. Overall changes in the pattern of ring width at breast height appeared to be a good indicator of growth performance as they were close to those for specific volume increment.

Variations in radial growth of declining old-growth stands of Abiesamabilis after tephra deposition from Mount St. Helens

1995 ◽  
Vol 25 (9) ◽  
pp. 1484-1492 ◽  
Author(s):  
Gerardo Segura ◽  
Thomas M. Hinckley ◽  
Linda B. Brubaker
Keyword(s):  
Time Series ◽  
Radial Growth ◽  
Time Series Models ◽  
Silver Fir ◽  
Growth Trend ◽  
Old Growth ◽  
Compensatory Response ◽  
Growth Changes ◽  
Original Time ◽  
Mount St Helens

Radial growth trends of old-growth mixed conifer forests were evaluated in areas impacted by tephra deposition from the 1980 eruption of Mount St. Helens, Washington. These areas were characterized by a crown decline in Abiesamabilis (Dougl.)Forbes (Pacific silver fir), associated with the long-term tephra retention by foliage. Post-1980 growth changes of A. amabilis were quantified using standard dendrochronological techniques in stands covering a range of crown decline conditions, amount of tephra deposited, elevation, and species composition. Time-series models revealed autocorrelations in the growth trend of all species at all sites. Intervention analysis quantified posteruption radial growth changes and significantly improved the description of the original time series models. Growth reductions of A. amabilis were generally consistent with the mean crown decline conditions of individual sites. However, the magnitude of growth reductions did not correspond closely to the decline condition of the stand. Abiesamabilis experienced significant post-1980 growth reductions in sites with high crown decline, but no growth changes were detected in sites with low decline. Tsugaheterophylla (Raf.)Sarg.(western hemlock) and Pseudotsugamenziesii (Mirb.) Franco (Douglas-fir), which consistently occurred with A. amabilis in the study area, did either not experience growth reductions or had significant positive growth after 1981. This positive post-disturbance growth could be explained as a compensatory response to the appreciable growth decline of A. amabilis.

Growth responses to climate and drought in silver fir (Abies alba) along an altitudinal gradient in southern Kosovo

2011 ◽  
Vol 41 (9) ◽  
pp. 1795-1807 ◽  
Author(s):  
Elvin Toromani ◽  
Mitat Sanxhaku ◽  
Edmond Pasho
Keyword(s):  
Radial Growth ◽  
Ring Width ◽  
Abies Alba ◽  
High Elevation ◽  
Negative Influence ◽  
Drought Indices ◽  
Silver Fir ◽  
Growth Responses ◽  
Spring Temperatures ◽  
The Impact

This paper deals with the response of silver fir ( Abies alba Mill.) growth to climate, mainly drought, presenting data from southern Kosovo, for which only little information is available. Two cores from 55 dominant trees were extracted at two sites representing the limits of the natural distribution of silver fir. We built 80- and 112-year-long chronologies for each site. Comparison of both ring width chronologies showed that they were diverse. Pointer year analysis indicated that high spring temperatures and ample rainfall (1082 mm) influenced positively silver fir growth (wide ring), while low spring temperatures and scarce precipitation had an inverse effect. Bootstrapped response functions confirmed that April and May temperatures of the current growth year influenced positively silver fir growth at the low-elevation site, while the July precipitation of the previous growth year had a negative influence. At the high-elevation site, warm previous December temperatures had a positive influence on silver fir growth. Drought indices indicated two periods (1953–1961 and 1994–2001) with moderate drought. Correlation analysis between silver fir radial growth and drought indices revealed that the impact of drought on radial growth was significant at the time scale of 1.5 months during the summer months.

Psychological Resilience Provides No Independent Protection From Suicidal Risk

Crisis ◽  
2016 ◽  
Vol 37 (2) ◽  
pp. 130-139 ◽  
Author(s):  
Danica W. Y. Liu ◽  
A. Kate Fairweather-Schmidt ◽  
Richard Burns ◽  
Rachel M. Roberts ◽  
Kaarin J. Anstey
Keyword(s):  
Risk Factors ◽  
Well Being ◽  
Current Status ◽  
Psychological Resilience ◽  
Cross Sectional ◽  
Life Project ◽  
Resilience Factors ◽  
First Time

Abstract. Background: Little is known about the role of resilience in the likelihood of suicidal ideation (SI) over time. Aims: We examined the association between resilience and SI in a young-adult cohort over 4 years. Our objectives were to determine whether resilience was associated with SI at follow-up or, conversely, whether SI was associated with lowered resilience at follow-up. Method: Participants were selected from the Personality and Total Health (PATH) Through Life Project from Canberra and Queanbeyan, Australia, aged 28–32 years at the first time point and 32–36 at the second. Multinomial, linear, and binary regression analyses explored the association between resilience and SI over two time points. Models were adjusted for suicidality risk factors. Results: While unadjusted analyses identified associations between resilience and SI, these effects were fully explained by the inclusion of other suicidality risk factors. Conclusion: Despite strong cross-sectional associations, resilience and SI appear to be unrelated in a longitudinal context, once risk/resilience factors are controlled for. As independent indicators of psychological well-being, suicidality and resilience are essential if current status is to be captured. However, the addition of other factors (e.g., support, mastery) makes this association tenuous. Consequently, resilience per se may not be protective of SI.

Testing the Strain Theory of Suicide – The Moderating Role of Social Support

Crisis ◽  
2020 ◽  
Vol 41 (2) ◽  
pp. 82-88 ◽  
Author(s):  
Bob Lew ◽  
Ksenia Chistopolskaya ◽  
Yanzheng Liu ◽  
Mansor Abu Talib ◽  
Olga Mitina ◽  
...  
Keyword(s):  
Social Support ◽  
Suicidal Behavior ◽  
Online Survey ◽  
Perceived Social Support ◽  
Strain Theory ◽  
Cross Sectional Survey ◽  
Cross Sectional ◽  
Psychological Strains ◽  
Moderating Role

Abstract. Background: According to the strain theory of suicide, strains, resulting from conflicting and competing pressures in an individual's life, are hypothesized to precede suicide. But social support is an important factor that can mitigate strains and lessen their input in suicidal behavior. Aims: This study was designed to assess the moderating role of social support in the relation between strain and suicidality. Methods: A sample of 1,051 employees were recruited in Beijing, the capital of China, through an online survey. Moderation analysis was performed using SPSS PROCESS Macro. Social support was measured with the Multidimensional Scale of Perceived Social Support, and strains were assessed with the Psychological Strains Scale. Results: Psychological strains are a good predictor of suicidality, and social support, a basic need for each human being, moderates and decreases the effects of psychological strains on suicidality. Limitations: The cross-sectional survey limited the extent to which conclusions about causal relationships can be drawn. Furthermore, the results may not be generalized to the whole of China because of its diversity. Conclusion: Social support has a tendency to mitigate the effects of psychological strains on suicidality.

Role of Sildenafil in the Treatment of Persistent Pulmonary Hypertension of Newborn (PPHN) - Should it Be Withdrawn from Market of Bangladesh due to Threat of being Misuses

2020 ◽  
Vol 35 (2) ◽  
pp. 100-104
Author(s):  
Maksudur Rahman ◽  
Mohammad Abdullah Al Mamun ◽  
MAK Azad Chowdhury ◽  
Abu Sayeed Munsi
Keyword(s):  
Intensive Care Unit ◽  
Intensive Care ◽  
Neonatal Intensive Care ◽  
Cross Sectional Study ◽  
Sectional Study ◽  
Cardiac Intensive Care Unit ◽  
Cross Sectional ◽  
Cardiac Intensive Care ◽  
Hospital Protocol

Background: Recently it has been apprehended that sildenafil, a drug which has been successfully using in the treatment of PPHN and erectile dysfunction in adult, is going to be withdrawn from the market of Bangladesh due to threat of its misuses. Objective: The aim of this study was to see the extent of uses of sildenafil in the treatment of PPHN and importance of availability of this drugs in the market inspite of its probable misuses. Methods: This cross sectional study was conducted in neonatal intensive care unit (NICU), special baby care unit (SCABU) and cardiac intensive care unit (CICU) of Dhaka Shishu (Children) Hospital from June, 2017 to May 2018. Neonates with PPHN were enrolled in the study. All cases were treated with oral sildenefil for PPHN along with others management according to hospital protocol. Data along with other parameters were collected and analyzed. Results: Total 320 patients with suspected PPHN were admitted during the study period. Among them 92 (29%) cases had PPHN. Male were 49(53 %) cases and female were 43(47%) cases. Mean age at hospital admission was 29.7±13.4 hours. Based on echocardiography,13(14%) cases had mild, 38 (41%) cases moderate and 41(45%) cases severe PPHN. Mean duration of sildenafil therapy was 11.9±7.1 days. Improved from PPHN were 83 (90%) cases. Mortality was 10% (9). Conclusion: In this study it was found that the incidence of PPHN is 29% among the suspected newborns. Sildenafil is successfull in improving the oxygenation of PPHN and to decrease the mortality of neonates. DS (Child) H J 2019; 35(2) : 100-104

Role of Fibrinolytic Therapy in Empyema Thoracis – A Hospital Based one year Cross Sectional Study

2012 ◽  
Vol 2 (2) ◽  
pp. 345-350
Author(s):  
Dr. Girish.L Dandagi ◽  
◽  
Venkat kalyana kumar. P ◽  
Dr. Dr.Isaac Mathew ◽  
Dr. Dr.G S Gaude Dr. Dr.G S Gaude
Keyword(s):  
Cross Sectional Study ◽  
Fibrinolytic Therapy ◽  
Empyema Thoracis ◽  
Sectional Study ◽  
Cross Sectional ◽  
One Year

Parliament as the Foreign Policy Actor: the Resources of the Parliamentary Diplomacy

2018 ◽  
Vol 42 ◽  
pp. 316-321
Author(s):  
Boris I. Ananyev ◽  
Daniil A. Parenkov
Keyword(s):  
Foreign Policy ◽  
International Security ◽  
New Technologies ◽  
Conservative Approach ◽  
National Interests ◽  
Policy Actor ◽  
Security Challenges ◽  
Essential Idea ◽  
Per Se

The aim of the article is to show the role of parliament in the foreign policy within the framework of the conservative school of thought. The authors examine both Russian and Western traditions of conservatism and come to the conclusion that the essential idea of “the rule of the best” has turned to be one of the basic elements of the modern legislative body per se. What’s more, parliament, according to the conservative approach, tends to be the institution that represents the real spirit of the nation and national interests. Therefore the interaction of parliaments on the international arena appears to be the form of the organic communication between nations. Parliamentary diplomacy today is the tool that has the potential to address to the number of issues that are difficult to deal with within the framework of the traditional forms of IR: international security, challenges posed by new technologies, international sanctions and other.

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