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.     

Acute effect of aflatoxin B1 on different inbred mouse strains II

The acute effects of Aflatoxin B₁(AFB₁) were evaluated on C57B1/6, CBA/J, B10A and Balb/c mice challenged with a single intraperitoneal dose of the mycotoxin (60 mg/Kg animal weight). 90 mice per strain were divided into three groups of 30 animals each: the intoxicated group and control groups I and II. Intoxicated mice were injected intraperitonealy with AFB₁ dissolved in corn oil, while control I mice received corn oil only (0.01 ml/g) by the same route. Lots of 10 animals from the intoxicated and control groups were sacrificed 24, 72 and 168 hours after challenge. Control mice II remained untreated and were used as standards of normality for biochemical (hepatic and renal function) and hematological evaluation. AFB₁ was detected in the liver of C57B1/6 and CBA/J mice 24 hours (1.46 and 0.75 ng/g, respectively), 72 hours (2.30 and 0.08 ng/g, respectively), and 168 hours (2.18 and 0.25 ng/g, respectively) after challenge. The mycotoxin was also observed in the liver of B10A mice (6.20 ng/g) 72 hours post-injection. The most evident histological lesions were observed 168 hours after treatment in C57B1/6 and B10A mice. Serum levels of alkaline phosphatase in intoxicated C57B1/6 and B10A mice were significantly higher than those of control I and II animals. The histopathologic lesions and biochemical changes were very discrete in Balb/c and CBA/J mice. It is included that strains C57B1/6 and B10A are more susceptible than strains CBA/J and Balb/c to the acute effects of AFB₁. Such difference probably reflects each strains's ability to biotransform and eliminate AFB₁ and its metabolites.     

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.     

Vacuolar remodelling mediates touch-induced androgynophore movement in Passiflora (Subg. Decaloba, Sect. Xerogona) flowers

Some species of the genus Passiflora (sect. Xerogona) have flowers that exhibit a mechanically-induced movement of the androgynophore that is probably involved in pollination. Despite the many reports of touch-induced movements of floral parts, the studies concerning anatomical, ultrastructural and molecular aspects of the plant movements are restricted to the vegetative parts. Rapid plant movements are highly dependent on turgor changes of a particular flexible tissue formed by specialized cells capable of losing and gaining water rapidly. Thigmotropic androgynophores of four species of Passiflora from section Xerogona were analyzed at cellular and subcellular levels. Our results show that the movement is due to a vacuolar remodelling in a group of parenchymatous cells at the base of the androgynophore. After the movement, plasmolyzed and multivacuolated cells are present at the stimulated side and turgid and univacuolated cells at the opposite side. The results suggest that the mechanisms leading to the androgynophore movement in Passiflora are, in general, analogous to those reported for the movements of legume pulvinus, motile stamen filaments and guard cells of stomata, pointing to conserved cellular mechanisms of plant movement.     

高原湿地草海水生植物多样性变化研究

采用文献对比,结合野外补点调查和观测,研究高原湿地草海水生植物多样性变化.结果表明：近三十年来,到草海越冬的黑颈鹤种群有逐渐增大趋势,1985年223只、2005年506只,到2011年约为1000只.2005年草海共有维管束植物49种,隶属25科37属,较1983年新增5科10属11种,2012年调查发现草海水生植被朝沼泽植被方向演替发展,荆三棱群落与水葱、李氏禾、水莎草和灯芯草群落一起发展为草海湖滨带主要优势挺水植物群落.空心莲子草在水体东部、东南及东北部入侵危害严重.外界干扰是草海生物多样性变化的主要原因,减少人为负面干扰、维护草海及周边环境稳定是保护和增加水生植物多样性的重要举措.     

Multi‐decadal range changes vs. thermal adaptation for north east Atlantic oceanic copepods in the face of climate change

Populations may potentially respond to climate change in various ways including moving to new areas or alternatively staying where they are and adapting as conditions shift. Traditional laboratory and mesocosm experiments last days to weeks and thus only give a limited picture of thermal adaptation, whereas ocean warming occurring over decades allows the potential for selection of new strains better adapted to warmer conditions. Evidence for adaptation in natural systems is equivocal. We used a 50‐year time series comprising of 117 056 samples in the NE Atlantic, to quantify the abundance and distribution of two particularly important and abundant members of the ocean plankton (copepods of the genus Calanus) that play a key trophic role for fisheries. Abundance of C. finmarchicus, a cold‐water species, and C. helgolandicus, a warm‐water species, were negatively and positively related to sea surface temperature (SST) respectively. However, the abundance vs. SST relationships for neither species changed over time in a manner consistent with thermal adaptation. Accompanying the lack of evidence for thermal adaptation there has been an unabated range contraction for C. finmarchicus and range expansion for C. helgolandicus. Our evidence suggests that thermal adaptation has not mitigated the impacts of ocean warming for dramatic range changes of these key species and points to continued dramatic climate induced changes in the biology of the oceans.