Rhythmic growth fluctuations in forest trees of Central Europe and the Front Range in Colorado

Summary Growth ring sequences in conifers and broadleaved trees show abrupt growth reductions persisting for several years. The frequency and duration of such reductions in almost 10000 trees in forest stands of Central Europe, in particular Switzerland, and in the Front Range, Colorado, USA, is related to species, climate and weather, and geographical unit. The growth reductions in the populations investigated are concentrated in certain periods and, in all species examined, essentially related to periods of drought in the spring and summer months. During the years covered by the study (1850–1985), periods of growth reduction occur in Central Europe, the Front Range, Colorado, and also in the Hudson Valley, New York, at irregular intervals of 6–34 years, and on average every 13–14 years. The growth reduction periods normally do not show synchronism between the three areas investigated. Regionally valid growth periodicities can only be definitely determined through the examination of a very large amount of material comprising a number of species growing in different forest stands and on different sites within a major phytosociological unit. Findings from studies on trees in different climatic areas or on few samples scarcely allow reliable comparisons.     

Assessment and illustration of cultural ecosystem services at the local scale – A retrospective trend analysis

There is a need to develop non-monetary methods for the assessment of cultural ecosystem services, in order to integrate them into the ES framework in a more balanced way. With this in mind, an adequate and comprehensive indicator base and mapping methods are required to communicate and discuss cultural ecosystem services, for it to be understood holistically. Referring to land use changes as an important driver for ES changes, we demonstrate the analysis of cultural ecosystem services trends, in a retrospective, as a supporting tool to better understand social and natural interactions as drivers behind land use changes, which are reflected in the landscape scene. There are two main outcomes of this study: (1) first, we developed and tested a catalogue of indicators as an approach to evaluate cultural ecosystem services trends at the local scale and (2) we established a mapping method for cultural ecosystem services trends in parallel with land use changes. This we did following the example of the afforestation processes which had taken place since the 19th century in the suburban area of Göttingen (Lower Saxony/Germany), called Hainberg. Our main conclusion is that cultural ecosystem services trends can indicate the reasons and drivers for land use changes that can be beneficial to forest/landscape management issues by means of the restoration of lost services. The proposed assessment method can be integrated into the development of future landscape plans, e.g. by providing information on historical guiding principles.     

Plasmodium berghei: Phase contrast and electron microscopical evidence that certain antimalarials can both inhibit and reverse pigment clumping caused by chloroquine

Chloroquine given parenterally to mice infected with Plasmodium berghei induces clumping of malarial pigment in intraerythrocytic parasites, as viewed by light microscopy. Quinine and candidate antimalarials WR 33,063, WR 171,669, WR 30,090, and WR 142,490 were singly tested for their ability to influence this clumping process if administered by gavage either before or after chloroquine. Phase constrast and electron microscopical studies showed that these agents not only can inhibit pigment clumping induced by chloroquine when given before chloroquine but can also reverse this process when given afterwards. Such reversal may be effected even if these agents are given at a time after chloroquine when hemozoin configuration consists exclusively of clumps.Electron microscopy on chloroquine-induced pigment clumping reversal by WR 30,090 and WR 33,063 provided evidence that this process, i.e., malarial pigment disaggregation, as seen by light microscopy may result from vesiculation of the postchloroquine enlarged food vacuole containing an aggregate of pigment particles and a pinching off therefrom of vesicles containing individual pigment particles, with a resultant scattering of these throughout the parasite cytoplasm.These studies demonstrate that an antimalarial's in vivo chloroquine-induced pigment dumping-inhibiting and reversing properties can serve as indicators of its oral bioavailability. Therefore, it is proposed that these properties should find application in a bioassay (preclinical primary screen) designed to evaluate the relative oral bioavailability of various physical dosage forms of any candidate antimalarial possessing such properties.     

Pollen‐based biomes for Beringia 18,000, 6000 and 0 14C yr bp†

The objective biomization method developed by Prentice et al. (1996) for Europe was extended using modern pollen samples from Beringia and then applied to fossil pollen data to reconstruct palaeovegetation patterns at 6000 and 18,000 ¹⁴C yr bp . The predicted modern distribution of tundra, taiga and cool conifer forests in Alaska and north‐western Canada generally corresponds well to actual vegetation patterns, although sites in regions characterized today by a mosaic of forest and tundra vegetation tend to be preferentially assigned to tundra. Siberian larch forests are delimited less well, probably due to the extreme under‐representation of Larix in pollen spectra. The biome distribution across Beringia at 6000 ¹⁴C yr bp was broadly similar to today, with little change in the northern forest limit, except for a possible northward advance in the Mackenzie delta region. The western forest limit in Alaska was probably east of its modern position. At 18,000 ¹⁴C yr bp the whole of Beringia was covered by tundra. However, the importance of the various plant functional types varied from site to site, supporting the idea that the vegetation cover was a mosaic of different tundra types.     

Lake Level Changes Recorded by Tree Rings of Lakeshore Shrubs:A Case Study at the Lake West-Juyan, Inner Mongolia, China

Variation in water resources is a main factor influencing ecohydrological processes and sustainable development in arid regions. Lake level changes are a useful indicator of the variability in water resources. However, observational records of changes in lake levels are usually too short to give an understanding of the long-term variability. In the present study, we investigated the tree rings of shrubs growing on the lakeshore of Lake West-Juyan, the terminus of the Heihe River in western China, and found that Lake West-Juyan had undergone degradation three times over the past 200 years. The lake level decreased from 904.3 to 896.8 m above sea level (a.s.l.) during the period 1800-1900, to 892.0 m a.s.l. from around 1900 to the late 1950s, and the lake dried out in 1963. The trend for changes in lake levels, which was represented by the composite chronology of three beach bars, showed that the phases of increasing lake levels over the past 150 years were during the periods 1852-1871, 1932-1952, 1973-1982, and 1995-1999. Comparison with the history of regional economic development showed that human activity has played an important role in regulating the water resources of the lower reaches of the Heihe watershed over the past 200 years.     

Binding of Chlorpromazine to S-100 Protein

Chlorpromazine (CPZ) induces in S-100 conformational changes resulting in the exposure of titratable SH groups of the protein to the solvent. This effect is even greater in the presence of Mg2+ +/- Ca2+. S-100 possesses binding sites for CPZ. The binding of CPZ to 3 microM S-100 is half-saturated by 0.18 microM CPZ in the presence of Mg2+ plus Ca2+ and by 0.24 microM CPZ in the presence of Mg2+ plus EGTA. The extent of the binding is greater in the presence of Ca2+ than in the presence of EGTA, especially at low CPZ concentrations.     

Present-day and mid-Holocene biomes reconstructed from pollen and plant macrofossil data from the former Soviet Union and Mongolia

Fossil pollen data supplemented by tree macrofossil records were used to reconstruct the vegetation of the Former Soviet Union and Mongolia at 6000 years. Pollen spectra were assigned to biomes using the plant-functional-type method developed by Prentice et al . (1996). Surface pollen data and a modern vegetation map provided a test of the method. This is the first time such a broad-scale vegetation reconstruction for the greater part of northern Eurasia has been attempted with objective techniques. The new results confirm previous regional palaeoenvironmental studies of the mid-Holocene while providing a comprehensive synopsis and firmer conclusions. West of the Ural Mountains temperate deciduous forest extended both northward and southward from its modern range. The northern limits of cool mixed and cool conifer forests were also further north than present. Taiga was reduced in European Russia, but was extended into Yakutia where now there is cold deciduous forest. The northern limit of taiga was extended (as shown by increased Picea pollen percentages, and by tree macrofossil records north of the present-day forest limit) but tundra was still present in north-eastern Siberia. The boundary between forest and steppe in the continental interior did not shift substantially, and dry conditions similar to present existed in western Mongolia and north of the Aral Sea.     

Comparative analysis of the tissue inflammatory response in human cutaneous and disseminated leishmaniasis

Cutaneous leishmaniasis (CL) is the most frequent clinical form of tegumentary leishmaniasis and is characterised by a single or a few ulcerated skin lesions that may disseminate into multiple ulcers and papules, which characterise disseminated leishmaniasis (DL). In this study, cells were quantified using immunohistochemistry and haematoxylin and eosin staining (CD4+, CD68+, CD20+, plasma cells and neutrophils) and histopathology was used to determine the level of inflammation in biopsies from patients with early CL, late CL and DL (ulcers and papules). The histopathology showed differences in the epidermis between the papules and ulcers from DL. An analysis of the cells present in the tissues showed similarities between the ulcers from localised CL (LCL) and DL. The papules had fewer CD4+ T cells than the DL ulcers. Although both CD4+ cells and macrophages contribute to inflammation in early CL, macrophages are the primary cell type associated with inflammation intensity in late ulcers. The higher frequency of CD20+ cells and plasma cells in lesions demonstrates the importance of B cells in the pathogenesis of leishmaniasis. The number of neutrophils was the same in all of the analysed groups. A comparison between the ulcers from LCL and DL and the early ulcers and papules shows that few differences between these two clinical forms can be distinguished by observing only the tissue.