scholarly journals 2-methyl-3-buten-2-ol: A Pheromone Component of Conifer Bark Beetles Found in the Bark of Nonhost Deciduous Trees

2012 ◽  
Vol 2012 ◽  
pp. 1-7 ◽  
Author(s):  
Qing-He Zhang ◽  
Fredrik Schlyter ◽  
Göran Birgersson
Keyword(s):  
Bark Beetles ◽  
Betula Pendula ◽  
Tropospheric Chemistry ◽  
Deciduous Tree ◽  
Deciduous Trees ◽  
Spruce Bark ◽  
Pheromone Components ◽  
The Common ◽  
Different Sources

Volatiles from bark of aspen,Populus tremulaL. and two species of birch: silver birch (Betula pendulaRoth.) and common birch (B. pubescensEhrh.), were collected by direct solvent extraction and aeration of both newly cut bark chips and undamaged stems in June 1998 and subjected to GC-MS analysis. The results showed the presence of 2-methyl-3-buten-2-ol (MB), one of the two principal aggregation pheromone components of the spruce bark beetle,Ips typographus, in bark extraction samples of all the three deciduous tree species tested. In addition, one more oxygenated hemiterpene, 3-methyl-3-buten-2-one, and (E)-3-penten-2-ol were also found in the bark extracts. Only trace amounts of MB were detected in some aeration samples of the fresh bark chips, and no MB was found from the aeration samples of undamaged stems at detectable levels. The occurrence of this compound was also confirmed in the bark of four exotic birch species:B. albosinensisSchneid.,B. ermaniiCham.,B. jacquemontiiSpach, andB. maximowiczianaRegel, but not yet in the European pines/spruces and the common yeasts. Our results raise major questions regarding the evolution, the tropospheric chemistry, and the ecological role of this hemiterpene alcohol. They also suggest that comparative studies on the biosynthetic pathways for MB in different sources would be of considerably evolutionary interest.

scholarly journals Bark beetles locate fungal symbionts by detecting volatile fungal metabolites of host tree resin monoterpenes

2021 ◽  
Author(s):  
Dinesh Kandasamy ◽  
Rashaduz Zaman ◽  
Yoko Nakamura ◽  
Tao Zhao ◽  
Henrik Hartmann ◽  
...  
Keyword(s):  
Bark Beetles ◽  
De Novo ◽  
Host Tree ◽  
Bornyl Acetate ◽  
Conifer Forest ◽  
Mature Trees ◽  
Breeding Sites ◽  
Spruce Bark ◽  
Short Period

Outbreaks of bark beetles have decimated millions of hectares of conifer forest worldwide in recent years. The ability of these tiny 3-6 mm long insects to kill mature trees over a short period has been ascribed to two factors: (1) mass attacks on the host tree to overcome tree defenses and (2) the presence of fungal symbionts that support successful beetle development in the tree. While the role of pheromones in coordinating mass attacks has been well studied, the role of chemical communication in maintaining the fungal symbiosis is poorly understood. We previously demonstrated that Eurasian spruce bark beetles (Ips typographus) can recognize beneficial fungal symbionts of the genera Grosmannia, Endoconidiophora and Ophiostoma by their de novo synthesized volatile compounds. We hypothesized that the fungal symbionts of the bark beetles might metabolize spruce resin monoterpenes of the beetle host tree, Norway spruce (Picea abies), and that the volatile products could be used as cues by beetles for locating breeding sites with beneficial symbionts. Grosmannia penicillata and other fungal symbionts altered the profile of spruce bark volatiles by converting the major monoterpenes to oxygenated derivatives. Bornyl acetate was metabolized to camphor, and α- and β-pinene to trans-4-thujanol and other oxygenated products. Extensive electrophysiological measurements showed that bark beetles possess olfactory sensory neurons that are selective for these oxygenated symbiont metabolites. Compounds such as camphor and trans-4-thujanol attracted beetles at specific doses in olfactory experiments and stimulated the response of female beetles to a mixture of pheromones. Finally, the fungal symbiont was found to stimulate bark beetle tunneling on diets. Collectively, our results show that oxygenated metabolites of conifer monoterpenes produced by fungal symbionts are used by bark beetles as cues to find these essential microbial symbionts. The oxygenated metabolites may aid beetles in assessing the presence of the fungus, the defense status of the host tree and the density of conspecifics at potential feeding and breeding sites.

Water Uptake in Deciduous Trees During Winter and the Role of Conducting Tissues in Spring Reactivation

IAWA Journal ◽  
1986 ◽  
Vol 7 (1) ◽  
pp. 31-38 ◽  
Author(s):  
Sam Essiamah ◽  
Walter Eschrich
Keyword(s):  
Fagus Sylvatica ◽  
Betula Pendula ◽  
Alnus Glutinosa ◽  
Deciduous Trees ◽  
Acer Pseudoplatanus ◽  
Relative Timing ◽  
European Species ◽  
Water Conduction ◽  
Timing Of Onset

In winter, deciduous trees lack any means for transpiration, nevertheless their buds swell and increase in weight. It is known that vessels play an important role in spring reactivation and that phloem may be involved since buds fail to break when twigs are ringed. This study investigates water/nutrient translocation from winter until reactivation in spring for five North European species: maple (Acer pseudoplatanus L.), birch (Betula pendula Roth), alder (Alnus glutinosa Gaertn.), beech (Fagus sylvatica L.), and ash (Fraxinus excelsior L.). Accordingly emphasis is laid on the relative timing of onset of water conduction among the species.

Changes of Starch Content in the Storage Tissues of Deciduous Trees During Winter and Spring

IAWA Journal ◽  
1985 ◽  
Vol 6 (2) ◽  
pp. 97-106 ◽  
Author(s):  
Sam. Essiamah ◽  
Walter Eschrich
Keyword(s):  
Fagus Sylvatica ◽  
Tree Species ◽  
Quercus Robur ◽  
Betula Pendula ◽  
Starch Content ◽  
Alnus Glutinosa ◽  
Deciduous Tree ◽  
Deciduous Trees ◽  
Acer Pseudoplatanus ◽  
Bud Break

Starch transformation in relation to spring sap production has been investigated in six North European deciduous tree species from fall till the beginning of bud break in spring. The species examined were: Acer pseudoplatanus L., Betula pendula Roth, Alnus glutinosa Gärtn., Fagus sylvatica L., Quercus robur L., and Fraxinus excelsior L.

Transmigration und Kapitalismus

2005 ◽  
Vol 35 (140) ◽  
pp. 407-422
Author(s):  
Julia Bernstein
Keyword(s):  
Soviet Union ◽  
Former Soviet Union ◽  
Different Sources

Based on an ethnographical study the article presents the problems of Soviet migrants with capitalistic every day life. The reaction of the migrants and the role of their imagination of capitalism, which was formed by different sources in the former Soviet Union, is investigated.

On everyday academic research

2017 ◽  
pp. 98-134 ◽  
Author(s):  
J. Tirole
Keyword(s):  
Common Good ◽  
Academic Research ◽  
Research Quality ◽  
Economic Research ◽  
Relevant Research ◽  
The Common ◽  
Verification Of Models ◽  
Science And Research

In the fourth chapter of the book “The economy of the common good”, the nature of economics as a science and research practices in their theoretical and empirical aspects are discussed. The author considers the processes of modeling, empirical verification of models and evaluation of research quality. In addition, the features of economic cognition and the role of mathematics in economic research are analyzed, including the example of relevant research in game theory and information theory.

Role of chromium (III) in the nutrition of pigs and cattle

2016 ◽  
Vol 3 (2) ◽  
pp. 56-62
Author(s):  
R. Iskra ◽  
V. Vlizlo ◽  
R. Fedoruk
Keyword(s):  
Growth And Development ◽  
Reproductive Function ◽  
Metabolic Effect ◽  
Considerable Part ◽  
Cultural Medium ◽  
Milk Performance ◽  
Chromium Compounds ◽  
The Impact ◽  
Different Sources

The results of our studies and the data of modern literature regarding the biological role of Cr(III) compounds in conditions of their application in the nutrition for pigs and cattle are discussed. The metabolic impact of Cr(III), coming from different sources – mineral and organic compounds, obtained by chemical synthesis or a nanotechnological method (chromium citrate), as well as in the form of biocomplexes from the cultural medium of Saccharomyces cerevisiae yeasts was analyzed. The metabolic connection between the impact of Cr(III) and the biosynthesis of some hormones – insulin, cortisol – as well as the sensitivity of some tissues and organs to the effect of chromium compounds was studied. A considerable part of the review material was dedicated to the metabolic effect of Cr(III) compounds on the reproductive function of pigs and cattle and their impact on the viability of the offspring and gametes of animals. The data about the stimulating effect of Cr(III) on the growth and development of the organism of piglets and calves, meat and milk performance of these species of animals are discussed. The relevance of dosing Cr(III) in the nutrition of pigs and cattle is highlighted.

Contemplative Principles of a Non-dual Praxis: the Unmediated Practices of the Tibetan ‘Heart Essence’ (sNying thig) Tradition

2015 ◽  
Vol 31 (2) ◽  
pp. 215-240
Author(s):  
Eran Laish
Keyword(s):  
Contemplative Practice ◽  
Tibetan Buddhist ◽  
Buddhist Tradition ◽  
The Common

This article focuses on the main contemplative principles of the ‘Heart Essence’ (sNying thig), a Tibetan Buddhist tradition that is characterized by a vision of non-duality and primordial wholeness. Due to this vision, which asserts an original reality that is not divided into perceiving subject and perceived object, the ‘Heart Essence’ advocates a contemplative practice that undermines the usual intuitions of temporality and enclosed selfhood. Hence, unlike the common principles of intentional praxis, such as deliberate concentration and gradual purification, the ‘Heart Essence’ affirms four contemplative principles of non-objectiveness, openness, spontaneity and singleness. As these principles transcend intentionality, temporality, and multiplicity, they are seen to directly disclose the nature of primordial awareness, in which the meanings of knowing and being are radically transformed. Therefore, the article will also consider the role of these non-dual contemplative principles in deeply changing our understanding of being and knowing alike.

Charles de Gaulle and European Community

2020 ◽  
Vol 2020 (10-3) ◽  
pp. 70-81
Author(s):  
David Ramiro Troitino ◽  
Tanel Kerikmae ◽  
Olga Shumilo
Keyword(s):  
World War Ii ◽  
European Community ◽  
World War ◽  
Charles De Gaulle ◽  
The United Kingdom ◽  
History Of ◽  
The Common ◽  
Post War ◽  
De Gaulle

This article highlights the role of Charles de Gaulle in the history of united post-war Europe, his approaches to the internal and foreign French policies, also vetoing the membership of the United Kingdom in the European Community. The authors describe the emergence of De Gaulle as a politician, his uneasy relationship with Roosevelt and Churchill during World War II, also the roots of developing a “nationalistic” approach to regional policy after the end of the war. The article also considers the emergence of the Common Agricultural Policy (hereinafter - CAP), one of Charles de Gaulle’s biggest achievements in foreign policy, and the reasons for the Fouchet Plan defeat.

“There is such a situation that Comrade Svoboda is under pressure”. The Soviet leadership and the settlement of relations with Czechoslovakia. May 1969

2019 ◽  
pp. 512-519
Author(s):  
Teymur Dzhalilov ◽  
Nikita Pivovarov
Keyword(s):  
Central Committee ◽  
Secretary General ◽  
Political Agenda ◽  
The Political ◽  
Soviet Government ◽  
Soviet Leadership ◽  
Policy Issues ◽  
The World ◽  
The Common

The published document is a part of the working record of The Secretariat of the CPSU Central Committee on May 5, 1969. The employees of The Common Department of the CPSU Central Committee started writing such working records from the end of 1965. In contrast to the protocols, the working notes include speeches of the secretaries of the Central Committee, that allow to deeper analyze the reactions of the top party leadership, to understand their position regarding the political agenda. The peculiarity of the published document is that the Secretariat of the Central Committee did not deal with the most important foreign policy issues. It was the responsibility of the Politburo. However, it was at a meeting of the Secretariat of the Central Committee when Brezhnev raised the question of inviting G. Husák to Moscow. The latter replaced A. Dubček as the first Secretary of the Communist party of Czechoslovakia in April 1969. As follows from the document, Leonid Brezhnev tried to solve this issue at a meeting of the Politburo, but failed. However, even at the Secretariat of the Central Committee the Leonid Brezhnev’s initiative at the invitation of G. Husák was not supported. The published document reveals to us not only new facets in the mechanisms of decision-making in the CPSU Central Committee, the role of the Secretary General in this process, but also reflects the acute discussions within the Soviet government about the future of the world socialist systems.

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