@article{EilmannBuchmannSiegwolfetal.2010, author = {Eilmann, Britta and Buchmann, Nina and Siegwolf, Rolf and Saurer, Matthias and Cherubini, Paolo and Rigling, Andreas}, title = {Fast response of Scots pine to improved water availability reflected in tree-ring width and δ13C}, series = {Plant, Cell and Environment}, volume = {33}, journal = {Plant, Cell and Environment}, number = {8}, publisher = {Wiley-Blackwell}, address = {Oxford}, issn = {1365-3040 (Online)}, doi = {10.1111/j.1365-3040.2010.02153.x}, pages = {1351 -- 1360}, year = {2010}, abstract = {Drought-induced forest decline, like the Scots pine mortality in inner-Alpine valleys, will gain in importance as the frequency and severity of drought events are expected to increase. To understand how chronic drought affects tree growth and tree-ring δ13C values, we studied mature Scots pine in an irrigation experiment in an inner-Alpine valley. Tree growth and isotope analyses were carried out at the annual and seasonal scale. At the seasonal scale, maximum δ13C values were measured after the hottest and driest period of the year, and were associated with decreasing growth rates. Inter-annual δ13C values in early- and latewood showed a strong correlation with annual climatic conditions and an immediate decrease as a response to irrigation. This indicates a tight coupling between wood formation and the freshly produced assimilates for trees exposed to chronic drought. This rapid appearance of the isotopic signal is a strong indication for an immediate and direct transfer of newly synthesized assimilates for biomass production. The fast appearance and the distinct isotopic signal suggest a low availability of old stored carbohydrates. If this was a sign for C-storage depletion, an increasing mortality could be expected when stressors increase the need for carbohydrate for defence, repair or regeneration.}, language = {en} } @article{EgliAyerPeteretal.2010, author = {Egli, Simon and Ayer, Fran{\c{c}}ois and Peter, Martina and Eilmann, Britta and Rigling, Andreas}, title = {Is forest mushroom productivity driven by tree growth? Results from a thinning experiment}, series = {Annals of Forest Science}, volume = {67}, journal = {Annals of Forest Science}, number = {5}, publisher = {Springer}, address = {Paris}, issn = {1286-4560 (Print)}, doi = {10.1051/forest/2010011}, pages = {509}, year = {2010}, abstract = {• Most of the edible forest mushrooms are mycorrhizal and depend on carbohydrates produced by the associated trees. Fruiting patterns of these fungi are not yet fully understood since climatic factors alone do not completely explain mushroom occurrence. • The objective of this study was to retrospectively find out if changing tree growth following an increment thinning has influenced the diversity patterns and productivity of associated forest mushrooms in the fungus reserve La Chan{\´e}az, Switzerland. • The results reveal a clear temporal relationship between the thinning, the growth reaction of trees and the reaction of the fungal community, especially for the ectomycorrhizal species. The tree-ring width of the formerly suppressed beech trees and the fruit body number increased after thinning, leading to a significantly positive correlation between fruit body numbers and tree-ring width. • Fruit body production was influenced by previous annual tree growth, the best accordance was found between fruit body production and the tree-ring width two years previously. • The results support the hypothesis that ectomycorrhizal fruit body production must be linked with the growth of the associated host trees. Moreover, the findings indicate the importance of including mycorrhizal fungi as important players when discussing a tree as a carbon source or sink.}, language = {en} } @article{RiglingEilmannKoechlietal.2010, author = {Rigling, Andreas and Eilmann, Britta and Koechli, Roger and Dobbertin, Matthias}, title = {Mistletoe-induced crown degradation in Scots pine in a xeric environment}, volume = {30}, number = {7}, publisher = {Oxford University Press}, address = {Oxford}, issn = {1758-4469 (Online)}, doi = {10.1093/treephys/tpq038}, pages = {845 -- 832}, year = {2010}, abstract = {Increasing Scots pine (Pinus sylvestris L.) mortality has been recently observed in the dry inner valleys of the European Alps. Besides drought, infection with pine mistletoe (Viscum album ssp. austriacum) seems to play an important role in the mortality dynamics of Scots pines, but how mistletoes promote pine decline remains unclear. To verify whether pine mistletoe infection weakens the host via crown degradation, as observed for dwarf mistletoes, we studied the negative effects of pine mistletoe infestation on the photosynthetic tissues and branch growth of pairs of infested and non-infested branches. Pine mistletoe infection leads to crown degradation in its host by reducing the length, the radial increment, the ramification, the needle length and the number of needle years of the infested branches. This massive loss in photosynthetic tissue results in a reduction in primary production and a subsequent decrease in carbohydrate availability. The significant reduction in needle length due to mistletoe infection is an indication for a lower water and nutrient availability in infested branches. Thus, mistletoe infection might lead to a decrease in the availability of water and carbohydrates, the two most important growth factors, which are already shortened due to the chronic drought situation in the area. Therefore, pine mistletoe increases the risk of drought-induced mortality of its host when growing in a xeric environment.}, language = {en} } @article{BragardSoltauThomasetal.2010, author = {Bragard, Michael and Soltau, N. and Thomas, S. and De Doncker, R. W.}, title = {The balance of renewable sources and user demands in grids : power electronics for modular battery energy storage systems}, series = {IEEE transactions on power electronics}, volume = {25}, journal = {IEEE transactions on power electronics}, number = {12}, publisher = {IEEE}, address = {New York}, issn = {0885-8993}, doi = {10.1109/TPEL.2010.2085455}, pages = {3049 -- 3056}, year = {2010}, abstract = {The continuously growing amount of renewable sources starts compromising the stability of electrical grids. Contradictory to fossil fuel power plants, energy production of wind and photovoltaic (PV) energy is fluctuating. Although predictions have significantly improved, an outage of multi-MW offshore wind farms poses a challenging problem. One solution could be the integration of storage systems in the grid. After a short overview, this paper focuses on two exemplary battery storage systems, including the required power electronics. The grid integration, as well as the optimal usage of volatile energy reserves, is presented for a 5- kW PV system for home application, as well as for a 100- MW medium-voltage system, intended for wind farm usage. The efficiency and cost of topologies are investigated as a key parameter for large-scale integration of renewable power at medium- and low-voltage.}, language = {en} } @article{BenzelLinzbach2010, author = {Benzel, Ute and Linzbach, Meike}, title = {Bilanzierung und Offenlegung von Ertragsteuerrisiken - Quo vadis? Unsichere Steuerpositionen in der Rechnungslegung nach IFRS, US-GAAP und HGB}, series = {IRZ - Zeitschrift f{\"u}r Internationale Rechnungslegung}, journal = {IRZ - Zeitschrift f{\"u}r Internationale Rechnungslegung}, number = {11}, issn = {1862-5533}, pages = {475 -- 523}, year = {2010}, abstract = {In den letzten drei bis vier Jahren unterlag der Bereich der Bilanzierung und Offenlegung von unsicheren Steuerpositionen im IFRS- und US-GAAP-Abschluss einem stetigen Wandel. Sowohl nach US-GAAP als auch nach IFRS nehmen die Anforderungen an die Bilanzierung und Offenlegung best{\"a}ndig zu. Schon allein dies zeigt die Bedeutung, die dem Themenbereich der Steuerrisiken beigemessen wird. Aber nicht nur im Rahmen der Berichterstattung im Jahresabschluss stehen Steuerrisiken oben auf der Agenda, auch der amerikanische Internal Revenue Service (IRS) verfolgt das Thema sehr konsequent und plant, bestimmte Unternehmen zu Angaben von Steuerrisiken im Rahmen der Steuererkl{\"a}rungen zu verpflichten. Der Aufsatz befasst sich mit den neueren Entwicklungen im Bereich der Bilanzierung und Offenlegung von unsicheren Steuerpositionen in der Rechnungslegung nach IFRS, US-GAAP und HGB und der Offenlegung von Steuerrisiken im Rahmen der Steuererkl{\"a}rung.}, language = {de} } @article{WollertLeidinger2010, author = {Wollert, J{\"o}rg and Leidinger, Rafael}, title = {Automation trifft Automotive : SPS in der Fahrzeugtechnik}, series = {Elektronik automotive : Magazin f{\"u}r Entwicklungen in der Kfz-Elektronik und Telematik}, journal = {Elektronik automotive : Magazin f{\"u}r Entwicklungen in der Kfz-Elektronik und Telematik}, number = {4/5}, publisher = {WEKA Fachmedien}, address = {Haar}, issn = {1614-0125}, pages = {44 -- 48}, year = {2010}, abstract = {Eine SPS im Kraftfahrzeug? Das geht ja gar nicht - da gibt es doch all die Hersteller f{\"u}r Kfz-Steuerger{\"a}te, die konfigurierbare Hardware anbieten. Im Prinzip ja, aber leider sind gerade die Sensoren oder Aktoren nicht ansteuerbar, die der Entwickler genau f{\"u}r sein aktuelles Projekt ben{\"o}tigt. Dieser Beitrag gibt einen kleinen Einblick in neue M{\"o}glichkeiten des Rapid Prototyping f{\"u}r mechatronische Systeme auf der Basis von Speicherprogrammierbaren Steuerungen (SPS).}, language = {de} } @article{DegeringEggertPulsetal.2010, author = {Degering, Christian and Eggert, Thorsten and Puls, Michael and Bongaerts, Johannes and Evers, Stefan and Maurer, Karl-Heinz and Jaeger, Karl-Erich}, title = {Optimization of protease secretion in Bacillus subtilis and Bacillus licheniformis by screening of homologous and herologous signal peptides}, series = {Applied and environmental microbiology}, volume = {76}, journal = {Applied and environmental microbiology}, number = {19}, publisher = {American Society for Microbiology}, address = {Washington, DC}, issn = {1098-5336 (E-Journal); 0003-6919 (Print); 0099-2240 (Print)}, doi = {10.1128/AEM.01146-10}, pages = {6370 -- 6378}, year = {2010}, abstract = {Bacillus subtilis and Bacillus licheniformis are widely used for the large-scale industrial production of proteins. These strains can efficiently secrete proteins into the culture medium using the general secretion (Sec) pathway. A characteristic feature of all secreted proteins is their N-terminal signal peptides, which are recognized by the secretion machinery. Here, we have studied the production of an industrially important secreted protease, namely, subtilisin BPN′ from Bacillus amyloliquefaciens. One hundred seventy-three signal peptides originating from B. subtilis and 220 signal peptides from the B. licheniformis type strain were fused to this secretion target and expressed in B. subtilis, and the resulting library was analyzed by high-throughput screening for extracellular proteolytic activity. We have identified a number of signal peptides originating from both organisms which produced significantly increased yield of the secreted protease. Interestingly, we observed that levels of extracellular protease were improved not only in B. subtilis, which was used as the screening host, but also in two different B. licheniformis strains. To date, it is impossible to predict which signal peptide will result in better secretion and thus an improved yield of a given extracellular target protein. Our data show that screening a library consisting of homologous and heterologous signal peptides fused to a target protein can identify more-effective signal peptides, resulting in improved protein export not only in the original screening host but also in different production strains.}, language = {en} } @article{ReisgenSchleserMokrovetal.2010, author = {Reisgen, Uwe and Schleser, Markus and Mokrov, Oleg and Ahmed, Essam}, title = {Uni- and bi-axial deformation behavior of laser welded advanced high strength steel sheets}, series = {Journal of materials processing technology}, volume = {210}, journal = {Journal of materials processing technology}, number = {15}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0924-0136}, doi = {http10.1016/j.jmatprotec.2010.08.003}, pages = {2188 -- 2196}, year = {2010}, abstract = {Bead-on-plate butt joints of 2.5 mm hot rolled DP600/DP600 and 1.2 mm cold rolled TRIP700/TRIP700 steel sheets were performed using 6 kW CO2 laser beam welding. The welding speed ranged from 1.5 to 3.0 and from 2.1 to 3.9 m/min in DP/DP and TRIP/TRIP steel weldments respectively. A top surface helium gas was used as a shielding gas at a flow rate of 20 l/min. Metallographic examinations and transverse tensile testing (DIN EN 895: 1995) were carried out to characterize the weldments. The formability of base metals and weldments were investigated by standard Erichsen test (DIN EN ISO 20482). It was found that the uniaxial plastic behavior of both DP600 and TRIP700 base metals was in agreement with Swift and modified Mecking-Kocks models respectively. In a perpendicular tensile test to the weld line, all specimens were fractured at the base metal however the strengths were somewhat higher than those of base metal. There was a significant reduction in formability caused by welding of both DP/DP and TRIP/TRIP steel weldments and the formability has been improved with the increase of the welding speed.}, language = {en} } @article{ReisgenSchleserJerabeketal.2010, author = {Reisgen, Uwe and Schleser, Markus and Jerabek, Jakub and Chudoba, Rostislav}, title = {Messung der Strahlqualit{\"a}t einer Elektronenstrahlanlage in Umgebungsatmosph{\"a}re}, series = {Materialwissenschaft und Werkstofftechnik}, volume = {41}, journal = {Materialwissenschaft und Werkstofftechnik}, number = {1}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {1521-4052}, pages = {45 -- 52}, year = {2010}, abstract = {In den letzten Jahrzehnten hat das Elektronenstrahlschweißen, das bereits im gr{\"o}ßeren Maßstab verwendet wird, seine F{\"a}higkeit als qualitatives Werkzeug f{\"u}r die Verbindung verschiedener Materialen nachgewiesen. Das Non Vacuum Electron Beam Welding (NV-EBW) hat zahlreiche Vorteile im Vergleich zum Elektronenstrahlschweißen im Vakuum, da man unter normalem Atmosph{\"a}rendruck arbeiten kann. Im Hinblick auf die reproduzierbare Qualit{\"a}t, insbesondere im Bereich der Massen-Fertigung, ist die Kontrolle der Strahlparameter sowie deren Einfluss auf das Schweißergebnis von großer Bedeutung. Durch eine genaue Kenntnis der Strahlkenngr{\"o}ßen wie des Strahldurchmessers und der Leistungsdichteverteilung kann eine Aussage {\"u}ber die sich ausbildende Schweißnaht sowie die Schweißbaddynamik getroffen werden. Messungen der Strahlkenngr{\"o}ßen im Prozess erlauben insbesondere die Untersuchung von Humping-Effekten. In diesem Beitrag wird der Prozess der Elektronenstrahlvermessung unter atmosph{\"a}rischen Bedingungen beschrieben. Es wird zudem die Abh{\"a}ngigkeit der Elektronenstrahlcharakteristika von den verschiedenen Prozessparametern dargestellt.}, language = {de} } @article{KuhnhenneDoeringFeldmann2010, author = {Kuhnhenne, Markus and D{\"o}ring, Bernd and Feldmann, Markus}, title = {Grunds{\"a}tze und L{\"o}sungen zur W{\"a}rmebr{\"u}ckenreduktion im Metallleichtbau}, series = {Stahlbau}, volume = {79}, journal = {Stahlbau}, number = {5}, publisher = {Ernst \& Sohn}, address = {Berlin}, issn = {1437-1049 (E-Journal); 0038-9145 (Print)}, doi = {10.1002/stab.201001330}, pages = {345 -- 355}, year = {2010}, abstract = {Die Anforderungen an das energiesparende Bauen sind mit der Einf{\"u}hrung der Energieeinsparverordnung (EnEV) 2009 auch im Industrie- und Gewerbebau deutlich versch{\"a}rft worden. Einen wesentlichen Beitrag zur Energieeinsparung liefert die Minimierung des Transmissionsw{\"a}rmetransfers. Analysiert man Geb{\"a}udeh{\"u}llen in Metallleichtbauweise stellt man fest, dass eine Erh{\"o}hung der W{\"a}rmed{\"a}mmst{\"a}rke allein noch nicht zielf{\"u}hrend ist, zus{\"a}tzlich sind W{\"a}rmebr{\"u}ckeneffekte zu ber{\"u}cksichtigen und deren Einfl{\"u}sse auf die W{\"a}rmetransmission zu reduzieren. Neben der Bedeutung f{\"u}r die Energieeinsparung ist eine w{\"a}rmetechnisch optimierte Detailausbildung auch erforderlich, um einen ausreichenden Feuchteschutz (Vermeidung von Tauwasser und Schimmelpilz) zu realisieren und so Sch{\"a}den zu vermeiden. Ein wichtiges Hilfsmittel stellt hierzu der vom Industrieverband f{\"u}r Bausysteme im Metallleichtbau (IFBS) herausgegebene W{\"a}rmebr{\"u}ckenatlas der Metall-Sandwichbauweise dar.}, language = {de} }