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1.
ICP Forest Monitoring data collected for more than 10 years made it possible to analyse key factors responsible for changes in forest conditions on a regional European scale. Observation routines may vary between different countries, which makes it difficult to gain more insight into stress-effect relationships. The effects on defoliation of Scots pine (Pinus sylvestris L.) of air concentrations and wet deposition of acidifying compounds, as well as effects of meteorological, site, stand and tree variables were investigated in Lithuania to test the hypothesis that spatial and temporal changes in pine defoliation were closely associated with atmospheric inputs of acidity. Over the period 1994–2004 crown defoliation of more than 8,000 pine trees was monitored in totally 45 stands distributed among three National Parks, where Integrated Monitoring Stations were situated. Air concentrations of SO2, and $ {\text{SO}}^{{{\text{2 - }}}}_{{\text{4}}} $ and $ {\text{NH}}^{{\text{ + }}}_{{\text{4}}} $ deposition, as well as spring and summer precipitation and mean winter temperature were shown to be the key factors affecting defoliation. The acidifying compounds accounted for nearly 58% of the variance in pine defoliation. Meteorological factors increased the degree of explanation to 65%, and stand and site variables to 79%.  相似文献   
2.

Silvopastoral systems integrate the complexity of forestry and forage-livestock management in an economically and ecologically sustainable way. However, these systems have undergone intensive pressure over the past decades caused by changes in land uses, as well as, in local socioeconomic priorities that suppressed traditional practices such as livestock grazing. These changes have caused land cover spatiotemporal diversifications whose effects were investigated in a traditional oak silvopastoral system at western Greece. In order to investigate the effect of human activities over the study area, the spatiotemporal land cover changes in conjunction with human and animal population changes and the environmental factors altitude, soil depth, inclination and rock type were analyzed. Also, forest-crown density changes were examined as a complimentary factor for the investigation of human intervention in the study area. Data about land-cover changes were derived from aerial orthorectified photographs of years 1945 and 2008, complimented by maps of environmental factors. Data digitization was implemented by the use of ArcGis. Based on the data analysis it derives that land cover changes are mainly attributed to direct human intervention. Environmental factors affect the ecosystem in two ways; first by affecting the location, type and intensity of human activities in the area, for example, soil depth determines where land is more productive and so predetermines the location, type and intensity of agricultural activities. Secondly, in the areas without or with minimal human intervention, environmental factors affect directly the land cover in conjunction with natural species necessities and their antagonistic capabilities.

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The oviposition pheromone of Culex quinquefasciatus was synthesized in a racemic form in a simple (five steps), efficient, high yielding (45% total yield), and low cost way (use of relatively low cost reagents). Our synthetic racemic pheromone (SRP) was tested in the laboratory for its bioactivity on Culex pipiens biotype molestus, which is a member of the species complex that Culex quinquefasciatusbelongs. In the testing conditions, bioactivity at the doses of 0.01, 0.1, 1, and 10 microg per cage was found with the best bioactivity achieved at 1 mug per cage. The effectiveness of our SRP offers a capable tool for improving mosquito oviposition traps for surveillance or even control programs.  相似文献   
5.
Lymphatic vessels develop from specialized endothelial cells in preexisting blood vessels, but the molecular signals that regulate this separation are unknown. Here we identify a failure to separate emerging lymphatic vessels from blood vessels in mice lacking the hematopoietic signaling protein SLP-76 or Syk. Blood-lymphatic connections lead to embryonic hemorrhage and arteriovenous shunting. Expression of slp-76 could not be detected in endothelial cells, and blood-filled lymphatics also arose in wild-type mice reconstituted with SLP-76-deficient bone marrow. These studies reveal a hematopoietic signaling pathway required for separation of the two major vascular networks in mammals.  相似文献   
6.
From the polar extracts of Origanum vulgare L. ssp. hirtum 19 compounds have been isolated. The structures and relative stereochemistry have been elucidated by spectroscopic analysis and determined as apigenin, luteolin, chrysoeriol, diosmetin, quercetin, eriodictyol, cosmoside, vicenin-2, caffeic acid, p-menth-3-ene-1,2-diol 1-O-beta-glucopyranoside, thymoquinol 2-O-beta-glucopyranoside, thymoquinol 5-O-beta-glucopyranoside, thymoquinol 2,5-O-beta-diglucopyranoside, 12-hydroxyjasmonic acid, 12-hydroxyjasmonic acid 12-O-beta-glucopyranoside, lithospermic acid B, rosmarinic acid, 10-epi-lithospermic acid, and epi-lithospermic acid B. The three latter products display unusual stereochemistry of the 3,4-hydroxyphenyllactic acid unit(s), which to the authors' best knowledge has never been reported before in similar compounds. Moreover, lithospermic acid B (and its stereoisomers), p-menth-3-ene-1,2-diol 1-O-beta-glucopyranoside, 12-hydroxyjasmonic acid, and 12-hydroxyjasmonic acid 12-O-beta-glucopyranoside were isolated for the first time from Origanum species.  相似文献   
7.
The molecular mechanisms controlling human hair growth and scalp hair loss are poorly understood. By screening about 350,000 individuals in two populations from the Volga-Ural region of Russia, we identified a gene mutation in families who show an inherited form of hair loss and a hair growth defect. Affected individuals were homozygous for a deletion in the LIPH gene on chromosome 3q27, caused by short interspersed nuclear element-retrotransposon-mediated recombination. The LIPH gene is expressed in hair follicles and encodes a phospholipase called lipase H (alternatively known as membrane-associated phosphatidic acid-selective phospholipase A1alpha), an enzyme that regulates the production of bioactive lipids. These results suggest that lipase H participates in hair growth and development.  相似文献   
8.
The incorporation of brewer's spent grain (BSG) into baked snacks (crispy-slices) was investigated in terms of nutritional, sensory and aromatic properties. Wheat flour was replaced with BSG at the levels of 10, 15 and 25%. Snacks containing 10% BSG exhibited high Crispiness index (Ci), low Crispiness work (Wc) and a high number of peaks during texture analysis, indicating that the crispiness of the samples was not negatively affected. However higher levels of BSG affected the texture and the crumb structure of snacks and the results were significantly different to the 100% wheat control. Addition of BSG altered the odour profile of the snacks as shown by the volatile profiles, however sensory results indicated that BSG-containing snacks at a level of 10% were highly acceptable and highlighted the possibility of using BSG as a baking ingredient in the formulation of enhanced fibre baked snacks.  相似文献   
9.
This report describes a whole-blood flow cytometric method for the determination of intracellular cytokines IFN-γ and IL-4 in canine T lymphocyte subpopulations. Conjugated anti-cytokine antibodies and commercially available reagents for cell fixation and permeabilization were used. Canine peripheral blood was cultured with a combination of phorbol-12-myristate-13-acetate (PMA) and ionomycin to promote cytokine synthesis in each cell, along with monensin to increase the sensitivity of the method by retaining IFN-γ and IL-4 within the cell to detectable levels. The optimum concentrations of PMA and ionomycin were determined. Maximum IFN-γ expression from both CD4+ and CD8+ T lymphocytes was detected after 6 h of incubation of cell culture, while maximum IL-4 production took 6 h from CD4+ cells and 4 h from CD8+ cells. This method is a simple immunologic technique for measuring intracellular cytokines which could be of value in the investigation of canine immunological response mainly in various intracellular and extracellular infections, since IFN-γ and IL-4 are considered key cytokines activating the cellular and humoral immunity, respectively.  相似文献   
10.
Alternaria dauci (Kühn) Groves and Skolko, the cause of leaf blight of carrot, was observed to produce chlamydospores and microsclerotia in vitro. Four different isolates produced chlamydospores on potato dextrose agar, V8 agar and Czapek-Dox agar at 10, 18 and 28°C, from neighbouring cells of hyphae of the submerged mycelium, forming long chains. Formation of chlamydospores was completed in a multiple stage process, including swelling of cells, development of secondary septa, rounding up of cells and cell wall thickening. Mature chlamydospores were released from the mycelium mostly in clusters and in short or long chains, and sometimes in pairs. They were globose to ellipsoid, smooth or verrucose, pale brown in colour, and averaged 13.87?×?11.37 μm, (length × width). Microsclerotia were formed on PDA, by only one isolate, at 28°C first at the edges of the colony, by close contact of hyphae that exhibited extensive branching and intermingling. In their final form microsclerotia were multi-celled, closely attached masses of short and broad dark grey cells, less compact woven at the edges of the microsclerotium. This is the first illustration of chlamydospore and microsclerotia formation in Alternaria dauci.  相似文献   
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