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This work reports on the synthesis of layered manganese oxides (&delta, MnO2) and their possible application as cathode intercalation materials in Al-ion and Zn-ion batteries. By using a one-pot microwave-assisted synthesis route in 1.6 M KOH (MnVII:MnII = 0.33), a pure layered &delta, MnO2 birnessite phase without any hausmannite traces was obtained after only a 14 h reaction time period at 110 &deg, C. Attempts to enhance crystallinity level of as-prepared birnessite through increasing of reaction time up to 96 h in 1.6 M KOH failed and led to decreases in crystallinity and the emergence of an additional hausmannite phase. The influence of MnII:OH&minus, ratio (1:2 to 1:10) on phase crystallinity and hausmannite phase formation for 96 h reaction time was investigated as well. By increasing alkalinity of the reaction mixture up to 2.5 M KOH, a slight increase in crystallinity of birnessite phase was achieved, but hausmannite formation couldn&rsquo, t be inhibited as hoped. The as-prepared layered &delta, MnO2 powder material was spray-coated on a carbon paper and tested in laboratory cells with Al or Zn as active materials. The Al-ion tests were carried out in EMIMCl/AlCl3 while the Zn-Ion experiments were performed in water containing choline acetate (ChAcO) or a ZnSO4 solution. Best performance in terms of capacity was yielded in the Zn-ion cell (200 mWh g&minus, 1 for 20 cycles) compared to about 3 mAh g&minus, 1 for the Al-ion cell. The poor activity of the latter system was attributed to low dissociation rate of tetrachloroaluminate ions (AlCl4&minus, ) in the EMIMCl/AlCl3 mixture into positive Al complexes which are needed for charge compensation of the oxide-based cathode during the discharge step.

Various Arabidopsis thaliana mutants with defects in phytohormone signal transduction or the reception of light were analysed with regard to their stomatal response in a red, red/blue light irradiation programme. Stomatal response to light was detected with a customized gas exchange measurement device, optimized for the small model plant. Small transpiration-kinetic variations of the two wild-type lines Columbia (Col) and Landsberg erecta (Ler) were observed. A comparison of the mutant lines to the respective wild type revealed significant differences for the phytochrome A (phyA-103), the abscisic acid insensitive (aba3-2) and the auxin resistant (axr1-3) mutant. Furthermore, the zeaxanthin-less mutant line npq1-2 showed no alterations in stomatal response to light.

Almost all land plants have developed a symbiosis with arbuscular mycorrhizal fungi. Establishment of the association is accompanied by structural changes in the plant root. During arbuscule formation fungal hyphae penetrate the root apoplast and install highly specialized interfaces for solute transport between plant and fungus. The periarbuscular membrane which is part of the plant plasma membrane surrounding arbuscular structures was shown to harbour a high density of different transport systems. Among these also expression of aquaporins was described, which potentially can act as a low affinity transport system for ammonia or ammonium. The present study provides data for expression, localization and function of plant aquaporins in the periarbuscular membrane of mycorrhizal Medicago truncatula plants.

This paper gives a summary of a project to characterize a tobacco aquaporin. The cDNA and gene, including the 5' upstream region, for the tobacco aquaporin NtAQP1 has been isolated and the encoded protein characterized. The significance of promoter regions for an abscisic acid- and gibberellic acid-induced gene expression could be restricted to a region between -1450 and -1112 upstream of the transcription start point by transient transformation of a bicistronic vector into tobacco protoplasts. NtAQP1 expression in tobacco plants was found to be elevated in flowers, stems and roots. In roots, the protein was detected close to xylem vessels in pitch-like structures. Studies with a NtAQP1-GFP fusion indicated a plasma membrane location. For a functional analysis, the cDNA was expressed in Xenopus oocytes. NtAQP1 was found to be a heavy metal-insensitive aquaporin with additional permeability for glycerol. Mutation of a threonine at position 233 to a cysteine transformed NtAQP1 into a heavy metal-sensitive aquaporin.

Young laboratory mice were kept from birth in a surrounding with one dominating synthetical odor substance (geraniol, C10H18O; experimentals); the controls were bred under normal conditions. Between postnatal days 10 and 35 the development of the neural activity in the olfactory bulb and the response to the synthetical (geraniol) and a natural odor (nest material) were tested at 6 different stages of age. By means of a computer the total energy and the frequency composition (power spectra) of the electrophysiologically leaded potentials were analyzed at the time of stimulation and without stimulation. The developmental increment of neural activity was retarded at the experimentals, but the typical high-frequency waves (oscillations) appeared about 5-6 days earlier than in the controls. Both odor substances induced neural responses measured by energy and frequency changes in the power spectra. In controls none of the odors leads to noticeable changes in the composition of frequencies at days 10 and 14. Beginning at postnatal day 18 the odor substances of nest material evoked increasing neural reactions; at all stages of age geraniol induced only slight alterations in the power spectra. In the experimentals responses could be measured first at day 14. The changes in power spectra rapidly increased in the following 3 weeks and the responses to geraniol reached several times more intense levels than in the controls. The influence of permanent olfactory stimuli on the ontogenetic development of the olfactory bulb and the extreme plasticity of this system are discussed.