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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Characterization Of Glutathione S-transferase Activity In Turkish Red Pine (pinus Brutia, Ten.): Variation In Environmentally Cold Stressed Seedlings

Boyoglu, Seyhan 01 January 2004 (has links) (PDF)
Plants can not escape from biotic and abiotic stress factors such as, extreme temperatures, high light intensity, drought, UV radiation, heavy metals, and pathogen attack. Plants have versatile defens systems against such stress conditions. In this study, the role of glutathione S-transferases (GSTs) in cold stress conditions were examined. Glutathione S-transferases are the enzymes that detoxify natural and exogenous toxic compounds by conjugation with glutathione. Glutathione, an endogenous tripeptide, is important as reducing agent, nucleophilic scavenger, and alleviate the chemical toxicity in the plants by the reaction of GSTs. Glutathione conjugates can be transported to the vacuoles or apoplast and are generally much less toxic than the parent compounds. In plants there are four distinct families of the soluble GSTs, namely Phi (F), Type I / Zeta (Z), Type II / Tau (U), Type III / Theta (T), Type IV. By contrast with the mammalian families of GST, relatively little is known about the plant GST families. Up to date, there is not any study on GST isolation and characterization from Turkish red pine, in this respect, this study well play a frontier role the future research dealing with this topic. In this study, some properties of Turkish red pine GST activity towards CDNB (1-chloro-2,4 dinitrobenzene) were examined. The average specific activity of Turkish red pine GST towards CDNB was found as 200&plusmn / 50 (Mean&plusmn / SE, n= 18) nmole/min/mg cytosolic protein. GSTs in cytosol prepared from Turkish red pine needles retained its activity without loss for four weeks at -80&amp / #61616 / C. The rate of conjugation reactions were linear up to 0.8mg of Turkish red pine cytosolic protein and 0.4 mg cytosolic protein was routinely used. The Turkish red pine GST showed its maximum activity at pH 8.0 in 25 mM phosphate buffer and 42 &amp / #730 / C. The measurements were carried out at room temperature (RT) of 25 &amp / #61616 / C. Turkish red pine GST seemed to be saturated at 1 mM CDNB and 1 mM GSH concentrations. The Vmax and Km values of Turkish red pine GST for CDNB was 416nmole/min/mg protein and 0,8 mM, respectively, and for GSH 106.4 nmole/min/mg protein and 0.10 mM, respectively. Turkish red pine cytosol was applied on DEAE-Sepharose fast flow column but almost no purification was achieved with respect GST activity. In order to examine the effects of cold stress on Turkish red pine GST activity, the GST activity was determined in 240 seedlings at &ndash / 3&amp / #61616 / , 0&amp / #61616 / and 13 &amp / #61616 / C environmental temperatures. It was observed that GST activity was the highest at -3&amp / #730 / C and the lowest at 13&amp / #730 / C in both cold resistant and sensitive families with the exception of Yaylaalan and &Ccedil / ameli.
22

Legacies of forest management and fire in mixed-pine forest ecosystems of the Seney National Wildlife Refuge, eastern Upper Michigan

Rist, Stephen George. January 2008 (has links)
Thesis (M.S.)--Ohio State University, 2008. / Title from first page of PDF file. Includes bibliographical references (p. 74-79).
23

Evaluation of an expert system approach to forest pest management of red pine (Pinus resinosa)

Schmoldt, Daniel Lee, January 1900 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1987. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 201-211).
24

Modeling statistical distributions and evaluating properties of mill-run lumber

Anderson, Guangmei Cao 30 April 2021 (has links) (PDF)
Although it is common to model modulus of elasticity (MOE) and modulus of rupture (MOR) of graded lumber as normal, lognormal, or Weibull distributions, recent theories and empirical practices have cast doubt on these models. Mathematical proofs have been used to shown how the MOR distributions of graded lumber can be derived from the MOR distributions of mill-run populations. The MOR distribution of a graded lumber subpopulation is "pseudo- truncated" and does not exhibit the same theoretical form as the mill-run population from which it was drawn. Therefore, it is essential to explore the properties of mill-run lumber populations and properly characterize their MOE and MOR distributions. To investigate this topic, this dissertation has three objectives: 1) to determine if the within-mill means and standard deviations of MOE and MOR in mill-run southern pine (Pinus spp.) lumber differ over time, 2) to determine the correlations among hand-held grain angle meter readings, MOE, and MOR in mill- run southern pine lumber, and 3) to model statistical distributions of MOE and MOR in mill-run red pine (Pinus resinosa) and spruce (Picea spp.) lumber. This research features four main sections: 1) an introduction summarizing the conclusions of each chapter, 2) a chapter investigating if there are statistically significant differences between the means and variances of MOE and MOR in mill-run southern pine lumber populations at the same mill over time, 3) a chapter evaluating the bivariate correlations among handheld grain angle meter readings, MOR, and three measures of MOE in mill-run southern pine lumber, and 4) a chapter modeling the distributions of MOE and MOR in mill-run red pine and spruce lumber populations and comparing those to previous work on mill-run southern pine lumber populations.
25

Legacies of forest management and fire in mixed-pine forest ecosystems of the Seney National Wildlife Refuge, eastern Upper Michigan

Rist, Stephen George 11 September 2008 (has links)
No description available.
26

Comparative Sequence Analysis Of The Internal Transcribed Spacer 2 Region Of Turkish Red Pine (pinus Brutia Ten.) And Natural Aleppo Pine (pinus Halepensis Mill.) Populations From Turkey

Tozkar, Ozge Cansu 01 April 2007 (has links) (PDF)
ABSTRACT COMPARATIVE SEQUENCE ANALYSIS OF THE INTERNAL TRANSCRIBED SPACER 2 REGION OF TURKISH RED PINE (Pinus brutia TEN.) AND NATURAL ALEPPO PINE (Pinus halepensis MILL.) POPULATIONS FROM TURKEY Tozkar, &Ouml / zge M.S., Department of Biology Supervisor: Prof. Dr. Zeki Kaya April, 2007, 107 pages Turkish red pine (Pinus brutia) is wide-spread and an important forest tree species in Turkey, occurring mainly in southern, western and north-western Turkey and as small isolated populations in the Black Sea region. Aleppo pine (Pinus halepensis) has naturally found only in Adana and Mugla provinces as small population in mixture with Turkish red pine. Although Turkish red pine and Aleppo pine are morphologically different, Turkish red pine has been regarded as subspecies of Aleppo pine by some taxonomists due to occurrence of natural hybridization between these two species. However, the phylogenic relationship between these species needs to be explored further. In the present study, by sampling overlapped populations of both species from Mugla and Adana provinces (4 populations of Turkish red pine and 3 populations of Aleppo pine), internal transcribed spacer (ITS) region of ribosomal DNA were comparatively studied with sequence analysis. Although ITS1, 5.8s and ITS2 regions of ribosomal DNA were studied with ITS primers, only ITS2 region was successfully amplified with polymerase chain reaction (PCR). The complete data set for this region was analysed using MEGA3.1 and Arlequin softwares. Analysis of molecular variance (AMOVA) demonstrated the highest genetic differentiation between Turkish red pine and Aleppo pine in Mugla with 100 percentage of variation. AMOVA analysis also indicated the possibility of low-level migration of genes between Turkish red pine and Aleppo pine populations in Adana with 50.65 percent of molecular variance. Haplotype comparison revealed that two major haplotypes were represented Based on the results of ITS2 region sequence analysis, Turkish populations of Aleppo pine and Turkish red pine populations could not be fully differentiated. In Mugla province Turkish red pine and Aleppo pine revealed more differentiation due to reproductive isolation. But in Adana province, two species shared more common genetic background due to possible hybridization. Since ITS2 region of nuclear ribosomal DNA revealed a few variable and parsimony informative sites for both species, thus, only ITS2 region of ribosomal DNA does not appear to be sufficient for fully resolving genetic relationships between Turkish red pine and Aleppo pine populations. Further studies including ITS1 and 5.8s regions of ribosomal DNA and populations included from major Aleppo pine distribution areas will be useful to understand the evolutionary relationship between Aleppo pine and Turkish red pine populations in Turkey.
27

Growth response of Pinus resinosa and Picea abies to past and future climatic variations

Djalilvand, Hamid. January 1996 (has links)
Growth responses to climatic variables of red pine (Pinus resinosa Aiton) and Norway spruce (Picea abies L. Karst) were studied at the Morgan Arboretum, near Montreal, in southern Quebec, Canada (45$ sp circ$ 25$ sp prime$ N, 73$ sp circ$ 57$ sp prime$ W; 15.2 m above sea level). The relationships between climatic variables and basal area growth were examined using linear and quadratic models. Current and previous year's climatic variables were tested separately and in combination using multiple regression models. The best models explained 82% and 85% of the total variance of the growth of Norway spruce and red pine, respectively. The growth of both species was more associated with evapotranspiration than precipitation. The growth of Norway spruce was best explained by the current year's annual evapotranspiration (43%), while the growth of red pine was more related to previous year's August evapotranspiration (33%) at our site. / The JABOWA model was used to predict tree growth in hypothetical climates which could result from global climate changes. Based on literature, five treatments were applied: normal, and increases of 1, 3, 5, and 10$ sp circ$C. Comparison between the last (1983-1992) and next (1993-2002) ten years growth showed no significant differences between species when temperature was normal or increased by 1 and 3$ sp circ$C, but significant differences between species were observed when the temperature was increased by 5$ sp circ$C. Both species declined when the temperature was increased by 10$ sp circ$C. We concluded that Norway spruce is more sensitive to increases in atmospheric temperatures than red pine at our site.
28

カラマツヤツバキクイムシに随伴する青変菌のカラマツとアカマツ苗木に対する接種

PENG, Xudong, 彭, 旭東, KAJIMURA, Hisashi, 梶村, 恒, SHIBATA, Ei'ichi, 柴田, 叡弌 12 1900 (has links) (PDF)
農林水産研究情報センターで作成したPDFファイルを使用している。
29

Growth response of Pinus resinosa and Picea abies to past and future climatic variations

Djalilvand, Hamid. January 1996 (has links)
No description available.
30

Cavity Presence in Snags Created Using Two Techniques in the Huron-Manistee National Forest

Nadler, Madison January 2020 (has links)
No description available.

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