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Unexpected cognitive lucidity and communication in patients with severe dementias, especially around the time of death, have been observed and reported anecdotally. Here, we review what is known about this phenomenon, related phenomena that provide insight into potential mechanisms, ethical implications, and methodologic considerations for systematic investigation. We conclude that paradoxical lucidity, if systematically confirmed, challenges current assumptions and highlights the possibility of network‐level return of cognitive function in cases of severe dementias, which can provide insight into both underlying neurobiology and future therapeutic possibilities.

Whilst forest policy promotes cultivation and regeneration of beech dominated forest ecosystems, beech itself is a highly drought sensitive tree species likely to suffer from the climatic conditions prognosticated for the current century. Taking advantage of model ecosystems with cool-moist and warm-dry local climate, the latter assumed to be representative for future climatic conditions, the effects of climate and silvicultural treatment (different thinning regimes) on water status, nitrogen balance and growth parameters of adult beech trees and beech regeneration in the understorey were assessed. In addition, validation experiments with beech seedlings were carried out under controlled conditions, mainly in order to assess the effect of drought on the competitive abilities of beech. As measures of water availability xylem flow, shoot water potential, stomatal conductance as well as d 13 C and d 18 O in different tissues (leaves, phloem, wood) were analysed. For the assessment of nitrogen balance we determined the uptake of inorganic nitrogen by the roots as well as total N content and soluble N compounds in different tissues of adult and young trees. Retrospective and current analysis of d 13 C, growth and meteorological parameters revealed that beech growing under warm-dry climatic conditions were impaired in growth and water balance during periods with low rain-fall. Thinning affected water, N balance and growth mostly of young beech, but in a different way under different local climatic conditions. Under cool, moist conditions, representative for the current climatic and edaphic conditions in beech forests of Central Europe, thinning improves nutrient and water status consistent to published literature and long-term experience of forest practitioners. However, beech regeneration was impaired as a result of thinning at higher temperatures and under reduced water availability, as expected in future climate.

Pedospheric nitrate uptake is a strongly regulated process adapted to the N demand of the whole plant. Pre-requisites for an integrating regulatory system are signal substances communicating the N demand of the shoot to the roots. In the current study it was shown that an additional atmospheric N source results in activation of cytokinins in the shoot as indicated by an increase in the trans -hydroxylation ratio, and in increased shoot-to-root transport of cytokinins in the phloem. Phloem mobility and basipetal transport of cytokinins were also demonstrated by feeding zeatin riboside into the phloem. The resulting enrichment of cytokinins in the roots caused an increased expression of a highaffinity nitrate transporter, the enrichment of amino compounds (Glu, Val, Phe, Lys) in the fine roots and a significant decrease in nitrate net uptake. Significant enrichment in amino acids -accompanied by decreased nitrate net uptake but not by increased expression of the highaffinity nitrate transporter -was also observed when Gln the major long-distance transport form of nitrogen in beech was fed into the phloem. These results provide experimental evidence that, in addition to amino compounds, cytokinins that are known to cycle within the plant are also communicating changes in N metabolism from the shoot to the roots. Apparently increased cytokinin contents in the root can transiently increase nitrate uptake, but this upregulation may be overridden by transcriptional and posttranscriptional down-regulation mediated by amino compounds.

In this article, we present the results of a literature survey on case reports of the unexpected return of mental clarity and memory shortly before death, which we have called "terminal lucidity." We focus specifically on terminal lucidity in mental disorders, of which we have found 81 case references. Of these, we were able to retrieve 49 case reports, most of which had been recorded before 1849. Thereafter, comparatively few reports of terminal lucidity have been published. Some more recent publications referred to terminal lucidity in patients suffering from schizophrenia and dementia. We draw parallels and distinctions between terminal lucidity and remissions attributable to febrile illness in neurosyphilis. We recommend in-depth studies on the psychopathology and neuropathology involved in terminal lucidity, since they might enable the development of both improved therapies and a better understanding of unresolved aspects of cognition and memory processing.

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Summary• We assessed the effect of climatic and canopy density changes on the seasonal patterns of total soluble nonprotein N (TSNN) in naturally regenerated beech ( Fagus sylvatica ) seedlings grown on limestone.• Leaves, roots, wood and phloem exudates from seedlings grown in control and thinned stands on a dry, warm SW-exposed site and a moist, cooler NE-exposed site were examined. The concentrations of amino compounds, ammonium and nitrate, comprising TSNN, were determined in May (new leaf expansion), July (mid-summer) and September (end of the growing season).• In May, Asn was augmented in leaves and roots at the NE site, whereas Arg dominated in leaves and phloem at the SW site. In July, all TSNN compounds declined, independent of site and treatment. In September, TSNN, and particularly Arg, increased in roots, phloem and wood at the SW site, compared with the NE.• TSNN indicates changes in the N status of beech seedlings, due to altered growth conditions. The drier and warmer climate at the SW site, relative to the NE, resulted in earlier N remobilization in spring and storage in autumn. Thinning improved the N status at the NE site, but impaired it at the SW site, by affecting differently the climatic conditions and soil nutrient balance of each site.

This article reviews the scholarly literature dealing with the perennial multipurpose crop Virginia mallow (Sida hermaphrodita (L.) Rusby; Sida in the following). In regions dominated by intensive agricultural management practices, growing Sida holds the potential to combine ecosystem services such as decreasing soil erosion, reducing nitrate leaching as well as enhancing biodiversity, with economic profit for the farmer. After promising biomass yields of Sida were reported from studies performed in Poland about 15 years ago, the interest in this plant species has continuously increased, and different utilization pathways were examined, predominantly by researchers in Poland and Germany. At present, however, a comprehensive overview that summarizes the different lines of research performed regarding the use of Sida is lacking. This review aims at closing this gap. After providing background information on Sida, we summarize the main results obtained from investigations concerning biomass yields, fertilization effects, key findings concerning direct combustion, biogas production, steam gasification, phytoremediation, and alternative utilization pathways. Thereafter, we highlight important aspects of Virginia mallow cultivation practices, including first estimates regarding the costs involved. Finally, we point to existing research gaps. Summarizing the available literature on Sida, we aim at raising the interest of scientists and farmers in this plant species further and to show where future research might tie in with, as the successful cultivation of Sida might represent a worthwhile strategy to transform current agricultural practices in Central Europe into approaches that are more sustainable and resilient against future challenges.