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Expression of selected genes in relation to phosphate (Pj) starvation and sugar sensing was studied in leaves of Arabidopsis. Excised leaf segments with different P status were supplied with combinations of P i and sugars. Sugar-inducible genes, encoding β-amylase (β-AMY) and chalcone synthase (CHS), were also induced by P deficiency, and were more strongly regulated by sugars when leaf segments originated from P-starved plants. Furthermore, transcript levels of the P-starvation-inducible genes ACP5 (encoding an acid phosphatase), RNS1 (encoding a ribonuclease), and IPS1 (unknown function) increased in response to exogenously applied sugars. Supply of P i to the leaf segments reversed both P-starvation-induced and sugar-induced gene expression. These interactions reveal a close relationship between P and sugar sensing. To differentiate between hexokinase-dependent and hexokinase-independent sugar sensing the effect of the glucose analogue 2-deoxyglucose and gene expression in the hexokinase-1 deficient mutant, gin2-1, were studied. Both β-AMY and CHS were induced by supplying sucrose to excised leaves but not by 2-deoxyglucose, confirming that these genes are regulated by hexokinase-independent sugar sensing. In the gin2-1 mutant both β-AMY and CHS responded clearly to P starvation excluding that hexokinase-1 mediates the response to P. Similarly, the P-responding genes, IPS1 and RNS1 were repressed by addition of P i also in the gin2-1 mutant. In conclusion, several phosphate starvation-induced genes are also sugar-induced and hexokinase-independent sugar sensing in Arabidopsis is strongly intensified by phosphate starvation.

SummaryThe transcription factor EIN3 is part of the ethylene signal transcription pathway in Arabidopsis. To investigate the genes involved in ethylene induced leaf and flower senescence in Rosa hybrida, a cDNA fragment encoding part of a transcription factor EIN3 homologue, termed RhEIN3, was isolated. The deduced proteinEIN3-fragment has 83% and 88% identity to the corresponding region of Arabidopsis EIN3 and EIL1, respectively. The gene RhEIN3 was constitutively and stably expressed in leaves of two cultivars, and during flower senescence in two rose cultivars with differences in flower life, even after ABA or ethylene treatment.

Berliner Glas is a privately owned, mid-sized manufacturer of precision opto-mechanics in Germany. One specialty of Berliner Glas is the design and production of high performance vacuum and electrostatic wafer chucks. Driven by the need of lithography and inspection for smaller overlay values, we pursue the production of an ideally flat wafer chuck. An ideally flat wafer chuck holds a wafer with a completely flat backside and without lateral distortion within the wafer surface. Key parameters in influencing the wafer chucks effective flatness are thermal performance and thermal management, roughness of the surface, choice of materials and the contact area between wafer and wafer chuck. In this presentation we would like to focus on the contact area. Usually this is decreased as much as possible to avoid sticking effects and the chance of trapped particles between the chuck surface and the backside of the wafer. This can be realized with a pin structure on the chuck surface. Making the pins smaller and moving pins further apart from each other makes the contact area ever smaller but also adds new challenges to achieve a flat and undistorted wafer on the chuck. We would like to address methods of designing and evaluating such a pin structure. This involves not only the capability to simulate the ideal pattern of pins on the chuck’s surface, for which we will present 2D and 3D simulation results. As well, we would like to share first results of our functional models. Finally, measurement capability has to be ensured, which means improving and further development of Fizeau flatness test interferometers.

To analyze differences in flower longevity and ethylene sensitivity, we isolated Rosa hybrida gene fragments with sequence similarity to the Arabidopsis thaliana ethylene receptor gene-family. A rose gene (RhETR1) highly similar to AtERS1 had been previously sequenced. Here, we report the isolation of three additional partial rose genes (RhETR2-4) belonging to different sub-groups of ethylene receptor genes. RhETR2 clusters with AtETR1, RhETR4 with AtERS1 and RhETR1, whereas RhETR3 shows high sequence similarity to AtETR2 and AtERS2. Expression analysis of RhETR2 and RhETR3 revealed that they are differentially expressed. RhETR2 is expressed at a constitutive level throughout flower development whereas RhETR3 expression increases in senescing flowers of the cultivar Bronze which has a short floral life while it remains at low levels in the long-lasting flowers of the cultivar Vanilla. Expression of both genes was increased by ABA and ethylene treatment, but transcript abundance differed between rose cultivars with different postharvest performance. These results indicate that differences in flower life among rose cultivars could be due to differences in receptor levels.

Exogenous application of ABA (abscisic acid) to intact miniature potted rose plants (Rosa hybrida L.) resulted in deterioration of postharvest quality of two cultivars. Spraying with ABA increased leaf drop and accelerated flower senescence in ‘Vanilla’ and ‘Bronze’, while bud drop was only induced in ‘Bronze’. Application of ABA to detached rose flowers accelerated their senescence, indicating that the observed senescence promoting effect was not a secondary response resulting from ABA-induced leaf senescence and abscission. ABA-treatment increased ethylene production in ‘Bronze’ flowers, while no ethylene production was measured in flowers of ‘Vanilla’, or in the leaves of both cultivars. Pre-treatment with 1-MCP (1-methylcyclopropene) delayed ABA promoted flower senescence in ‘Bronze’, suggesting that the effect of ABA is at least partly mediated by ethylene. The senescence promoting effect of ABA on leaf drop and flower life of ‘Vanilla’ flowers was not counteracted by 1-MCP pre-treatment. The cultivar ‘Vanilla’ had a low ABA level at all flower stages, while ABA content of the ‘Bronze’ petals was high in buds, lower in open flowers, and increased during flower senescence. An increased ABA content after ethylene treatment in ‘Vanilla’ suggests that ethylene, natural or exogenous, can increase ABA levels of flowers.

Commercial miniature potted rose cultivars ( Rosa hybrida L.) varied dramatically in their postharvest life. In some short-lived cultivars such as `Bronze,' 100% of the flowers faded after 12 days. In long-lived cultivars like `Vanilla' or `Charming,' less than 10% loss in display quality took place after the same period. Flower senescence in some cultivars was accompanied by a clear climacteric rise in ethylene production, in others there was only moderate or very low ethylene production. Leaf, bud abscission and flower senescence were accelerated when plants were exposed to exogenous ethylene, and there were marked differences in sensitivity and response to ethylene among cultivars. Longevity in the absence of ethylene was apparently related to timing of the onset of ethylene production. One cultivar with excellent longevity in air was also almost insensitive to exogenous ethylene, and indicates the potential for a breeding approach to increasing postharvest longevity of these plants.

SummaryThe influence of the ethylene action inhibitors STS and 1-MCP on poststorage performance and subsequent rooting of cuttings was investigated in Epipremnum pinnatum. Unfavourable storage conditions resulted in decreasing poststorage quality of single-eye cuttings, expressed as leaf drop and yellowing. 1-MCP and STS prohibited leaf drop and yellowing in E. pinnatum. STS pretreatment decreased rooting ability significantly, measured as percentage of rooted cuttings, number of roots, total root length and dry weight. STS caused severe injuries to the cuttings, which were worse if the cuttings were stored rather than propagated immediately. There was no significant difference in rooting between 1-MCP treated cuttings and untreated control in either stored or unstored cuttings. The influence of ethylene action inhibitors on rooting and a possible use of 1-MCP for practical use to increase poststorage performance in cuttings are discussed.

Indoor plants can remove volatile organic compounds (VOCs) from the air. The majority of knowledge comes from laboratory studies where results cannot directly be transferred to real-life settings. The aim of this study was to develop an experimental test system to assess VOC removal by indoor plants which allows for an improved real-life simulation. Parameters such as relative humidity, air exchange rate and VOC concentration are controlled and can be varied to simulate different real-life settings. For example, toluene diffusion through a needle gave concentrations in the range of 0.10-2.35 μg/L with deviations from theoretical values of 3.2-10.5%. Overall, the system proved to be functional for the assessment of VOC removal by indoor plants with Hedera helix reaching a toluene removal rate of up to 66.5 μg/m(2)/h. The mode of toluene exposure (semi-dynamic or dynamic) had a significant influence on the removal rate obtained by H. helix.

Advanced glycation endproducts (AGEs), structural components of beta-amyloid plaques and neurofibrillary tangels, have been implicated in the pathogenesis of Alzheimer's disease. AGE levels, measured by fluorescence, and their precursor molecules such as glucose and its Amadori product, fructosylamine, were measured to examine the question whether the reported increased level of AGEs in the brain is reflected in an increase in AGE-associated parameters in peripheral blood. Lactoferrin, proposed to play an important role in the interaction of AGEs with their receptors, was determined by ELISA. All AGE-associated parameters showed trends to lower values in patients with Alzheimer's disease compared with non-demented controls. Albumin and total iron were not significantly different between the groups. In contrast to diabetes and renal failure, where high levels of AGEs and their precursors are present in tissue as well as in peripheral blood, elevated CNS AGE levels in patients with Alzheimer's disease are manifested without detectable peripheral changes.

Several fluorescence techniques were used to detect cellular components within the hyphae of Aspergillus awamori. Single-stranded RNA (ss RNA) and double-stranded nucleic acids (ds RNA and DNA) were localized in mycelial hyphae and pellets of Aspergillus awamori by means of acridine orange (AO) staining. Pyronine Y/methyl green (PY/MG) staining allowed the localization of ds RNA and DNA, but no ss RNA in the cells. The replicating DNA was localized by the detection of the incorporated thymidine analogue (BrdU) via immunofluorescence. The ss RNA marks the local protein production in the cells. It indicates that the main protein production occurs in subapical and branching zones of the hyphae. In pellets no protein synthesis was observed in the corpus, but only in the hyphae on the pellet periphery. The replicating DNA observed in subapical and branching zones and nucleus indicates the cell propagation. On account of the intensive yellow fluorescence of the wheat bran, it was not possible to identify the cells with replicating DNA growing on a complex medium. By means of the vitality staining by fluorescein diacetate (PDA) and propidium iodide (PI) no internal hyphal structures were observed. The ethidium bromide (EB) is more suitable for structural investigations. The protein staining with fluorescein isothiocyanate (FITC) does not give useful information on the protein production, because of low fluorescence intensity, rapid fading and low selectivity.

Aspergillus awamori was cultivated in shake flask cultures and in stirred tank reactors on synthetic medium and on complex medium, (with wheat bran substrate), respectively, and samples were taken at different cultivation times. The filamentous mycelia and pellets of the fungus were analyzed using four different techniques: transmission electron microscopy (TEM), electron spectroscopic imaging (ESI), electron energy loss spectroscopy (EELS) and immunocytochemical investigations. The ultrastructure of A. awamori and the colonization and decomposition of the wheat bran by the fungus were determined as a function of the cultivation time. The xylanase concentration in the cytoplasm and cell wall of the fungus was high during the first phase of the cultivation and it gradually decreased due to its secretion. At the same time the xylanase concentration increased on the surface of the solid substrate as well as in the cultivation medium. The variation of the local distribution of the enzyme xylanase during the cultivation was determined as well. It is shown how the fungus penetrates and decomposes the wheat bran. Phosphorous and sulfur inclusions, determined with ESI and EELS, were found in the vacuoles.

Le present article traite des limites des nomes egyptiens, remontant a leur creation, et des steles erigees les materialisant, symboles d'un pouvoir politique etabli.

The transannular Diels–Alder reaction of 15-membered macrocyclic trienes with a trans-trans-cis (TTC) olefin geometry can lead to A.B.C.[6.6.7] tricyclic products of trans-syn-trans (TST) and cis-syn-cis (CSC) stereochemistry whereas the TTT isomers can produce the trans-anti-cis (TAC) and cis-anti-trans (CAT) tricycles. In order to study the influence of the position (pro-6.6 or pro-6.7) and the nature (alkyl, alkoxymethyl, or formyl) of the dienophile substituent, a set of 10 model cyclopentadecatrienes was prepared. The synthesis of appropriately functionalized trisubstituted dienophile and diene synthons, as well as their coupling reactions affording acyclic precursors, is described in this paper (first in a series of two). A mild and efficient macrocyclization protocol yielded the required methyl- or alkoxymethyl-substituted cyclic substrates. Further transformations led to the formyl-substituted ones. In particular, the TTT macrocycles containing an enal as a dienophile could be completely isomerized to the corresponding TTC thermodynamic isomers in acidic aqueous media. Keywords: transannular, Diels–Alder, 15-membered ring, A.B.C.[6.6.7] tricycles, diterpene.

In the preceding paper (Part I) we described the preparation of 10 model TTT and TTC cyclopentadecatrienes. Their conversion to A.B.C.[6.6.7] tricyclic products via a transannular Diels–Alder (TADA) reaction and the analysis of the resulting diastereoselection along with proofs of structures are described in the present article (Part II). The required temperature of reaction was significantly higher (~100 °C) in comparison to that required for the 14-membered lower homologs, indicating that proximity effects are playing a key role in the TADA reaction. The presence of ester groups in the chain was found to favor either of the two possible transition states (endo or exo) on the basis of steric effects, thus controlling the TST/CSC ratio of tricycles from TTC macrocycles, and the TAC/CAT ratio from TTT macrocycles. A formyl substituent on the dienophile can further influence the diastereoselection through the hypothesis of unsymmetrical transition states and allowed, for the first time, the use of Lewis acids as catalysts in the TADA reaction. This investigation demonstrates a general methodology for the stereocontrolled synthesis of A.B.C.[6.6.7] tricycle structures related to several polycyclic natural products. Keywords: transannular, Diels–Alder, 15-membered ring, A.B.C.[6.6.7] tricycles, diterpene.

Egyptian sources for crimes and punishments are extremely diverse. They mainly consist of royal texts, particularly decrees, administrative texts, specifically court proceedings, and texts of private origin, including biographies or letters. A written code of criminal law does not exist. Religious texts, especially chapter 125 of the Book of the dead, curses, and literary texts, especially didactic literature, also provide hints about criminal behavior and justice. Keywords: crime; Egyptian history; legal history

KEY MESSAGE : The P ( SAG12 ) -ipt gene was transferred to miniature rose, as the first woody species, resulting in increased ethylene resistance due to specific up-regulation of the ipt gene under senescence promoting conditions. Transgenic plants of Rosa hybrida 'Linda' were obtained via transformation with Agrobacterium tumefaciens strain harboring the binary vector pSG529(+) containing the P( SAG12 )-ipt construct. A. tumefaciens strains AGL1, GV3850 and LBA4404 (containing P(35S)-INTGUS gene) were used for transformation of embryogenic callus, but transgenic shoots were obtained only when AGL1 was applied. The highest transformation frequency was 10 % and it was achieved when half MS medium was used for the dilution of overnight culture of Agrobacterium. Southern blot confirmed integration of 1-6 copies of the nptII gene into the rose genome in the tested lines. Four transgenic lines were obtained which were morphologically true-to-type and indistinguishable from Wt shoots while they were in in vitro cultures. Adventitious root induction was more difficult in transgenic shoots compared to the Wt shoots, however, one of the transgenic lines (line 6) was rooted and subsequently analyzed phenotypically. The ipt expression levels were determined in this line after exposure to exogenous ethylene (3.5 μl l(-1)) and/or darkness. Darkness resulted in twofold up-regulation of ipt expression, whereas darkness combined with ethylene caused eightfold up-regulation in line 6 compared to Wt plants. The transgenic line had significantly higher content of chlorophyll at the end of the treatment period compared to Wt plants.

I. Durch die Veroffentlichung der Geburt der Tragodie hat sich N. in der deutschen Altphilologie sein junges Renomme verspielt. Die Mehrheit der Fachkollegenschaft akzeptierte die barschen Urteile von Wilamowitz (Zukunftsphilologie!, Berlin 1872; vgl. seine Erinnerungen, Leipzig, 1928, 129: »Uberhaupt schien mir alles herabgewurdigt, was ich von Pforte als etwas unantastbar Heiliges mitgenommen hatte«) und Usener (dieser hatte 1872 vor seinen Studenten erklart, N. sei »wissenschaftlich todt«: vgl. Rohde 25. 10. 1872).

Inorganic phosphate (Pi) is an essential nutrient for plants, and the low bioavailability of Pi in soils is often a limitation to growth and development. Consequently, plants have evolved a range of regulatory mechanisms to adapt to phosphorus-starvation in order to optimise uptake and assimilation of Pi. Recently, significant progress has been made in elucidating these mechanisms. The coordinated expression of a large number of genes is important for many of these adaptations. Several global expression studies using microarray analysis have been conducted in Arabidopsis thaliana. These studies provide a valuable basis for the identification of new regulatory genes and promoter elements to further the understanding of Pi-dependent gene regulation. With focus on the Arabidopsis transcriptome, we extract common findings that point to new groups of putative regulators, including the NAC, MYB, ethylene response factor/APETALA2, zinc-finger, WRKY and CCAAT-binding families. With a number of new discoveries of regulatory elements, a complex regulatory network is emerging. Some regulatory elements, e.g. the transcription factor PHR1 and the microRNA (miRNA) miR399 and associated factors are well documented, yet not fully understood, whereas other suggested components need further characterisation. Here, we evaluate the contribution of the regulatory elements to the P-responses and present a model comprising factors directly or indirectly involved in transcriptional regulation and the role of miRNAs as regulators and long-distance signals. A striking feature is a series of feedback loops and parallel mechanisms that can modify and attenuate responses. We suggest that these mechanisms are instrumental in providing an accurate response and in keeping P-homeostasis.

Growth retardation is an important breeding aim and an essential part of horticultural plant production. Here, the potential of transferring the Arabidopsis short internode (shi) mutant phenotype was explored by expressing the AtSHI gene in the popular ornamental plant Kalanchoe. A 35S-AtSHI construct was produced and transferred into eight genetically different cultivars of Kalanchoe by Agrobacterium tumefaciens. The resulting transgenic plants showed dwarfing phenotypes like reduced plant height and diameter, and also more compact inflorescences, as a result of increased vegetative height. The shi phenotype was stable over more than five vegetative subcultivations. Compared with Arabidopsis, the ectopic expression of AtSHI in Kalanchoe showed several differences. None of the Kalanchoe SHI-lines exhibited alterations in leaf colour or morphology, and most lines were not delayed in flowering. Moreover, continuous treatment of lines delayed in flowering with low concentrations of gibberellins completely restored the time of flowering. These features are very important as a delay in flowering would increase plant production costs significantly. The effect of expression controlled by the native Arabidopsis SHI promoter was also investigated in transgenic Kalanchoe and resulted in plants with a longer flowering period. Two AtSHI like genes were identified in Kalanchoe indicating a widespread presence of this transcription factor. These findings are important because they suggest that transformation with the AtSHI gene could be applied to several species as a tool for growth retardation, and that this approach could substitute the use of conventional chemical growth regulation in plant production.

The transannular Diels-Aider reaction of trans-trans-trans 15-membered macrocyclic trienes 1 - 5 leading to A.B.C.[6.6.7] tricyclic compounds is described.

The transannular Diels-Alder reaction of trans-trans-cis 15-membered macrocyclic trienes 1, 6 , and 7 leading to A.B.C.[6.6.7] tricyclic compounds is described.

Thermoresponsive polymer-coated surfaces based on poly(2-(2-methoxyethoxy)ethyl methacrylate-co-oligo(ethylene glycol) methacrylate) [P(MEO(2)MA-co-OEGMA)] allow switching between cell attachment and detachment. Here, we investigate the temperature-dependent surface interactions between the polymer coating and a colloidal probe in an aqueous medium by means of atomic force microscopy (AFM) force-distance measurements. The analysis of the adhesion forces from AFM retraction curves identifies two kinds of regimes for the copolymer at temperatures below and above the lower critical solution temperature (LCST). Whereas at 25 degrees C the surface interactions with the polymer in the swollen state are dominated by repulsive forces, at 37 degrees C the surface interactions switch to attractive forces and a stronger adhesion is detected by AFM. Running several heating/cooling cycles repeatedly shows that switching the surface properties provides reproducible adhesion force values. Time-dependent measurements give insight into the switching kinetics, demonstrating that the cell response is coupled to the polymer kinetics but probably limited by the cellular rearrangements.