Enzymic Preparation of Benzyl β-D-Glucopyranoside

Benzyl β-D-glucopyranoside was prepared by an enzyme-catalysed direct reaction between D-glucose, or better cellobiose, and benzyl alcohol in the presence of a minimum amount of water. The enzyme β-glucosidase was used in the immobilized form (adsorbed onto macroporous polyethylene terephthalate or covalently bound on polyglycidyl methacrylate), enabling multiple application.     

Numerical syntaxonomy of the tall-forb and tall-grass communities in the Tatra Mountains

The tall-forb and tall-grass subalpine and alpine vegetation belonging to the Mulgedio-Aconitetea from the Tatra Mountains was subjected to reclassification with Complete Linkage Clustering. The communities are classified into 3 alliances: Adenostylion, Calamagrostion villosae and Trisetion fusci. It was concluded that the orders Adenostyletalia and Calamagrostietalia villosae should be fused into one unit. Synecological relations of the communities was clarified using a series of Detrended Correspondence Analyses.Abbreviations CLC = Complete Linkage Clustering - DCA = Detrended Correspondence Analysis     

High-altitude vegetation of the Western Carpathians — a syntaxonomical review

This paper presents a survey of high-altitude plant communities which occur in the Western Carpathians with an enumeration of the characteristic, transgressive and differential species of the individual alliances, orders and classes. It describes the tall-herb vegetation (Mulgedio-Aconitetea) and communities of the subalpine shrubs (Betulo carpaticae-Alnetea viridis), the montane and alpine calcareous swards (Elyno-Seslerietea), the wind-exposed cryophilous swards on ridge edges with low snow cover (Carici rupestris-Kobresietea bellardii), the chionophilous communities of snow beds and snow fields (Salicetea herbaceae), the arctic-boreal dwarf-shrub heathlands (Loiseleurio-Vaccinietea), the alpine acidophilous grasslands (Caricetea curvulae) and the high-mountain mat-grass swards of the alliance Nardion strictae (Nardetea strictae).     

Genetic diversity affects productivity in early but not late stages of stand development

Recent declines in the genetic diversity of populations have stimulated research on the importance of genetic diversity for the functioning of natural communities. Current studies on this topic are based on the exploration of a limited number of clones and do not allow distinctions to be made between the effects of genetic identity and genetic diversity per se and to evaluate the effects of genetic diversity in genetically diverse communities. Also, most information comes from short-term studies, which are insufficient for evaluating the long-term effects relevant in relatively undisturbed communities of perennial species.We explored the importance of clone diversity vs. clone identity for stand productivity and the changes of the pattern over time. We used 18 clones of a perennial grass, Festuca rubra, to establish a set of communities composed of 1, 6 or 18 clones in two environments and studied the effects of genetic diversity on stand productivity over 3 years.Genetic diversity had a significant effect on stand productivity in the 1st year but not in the 2nd or 3rd year. In most cases, the observed yield was not significantly different from the total expected yield. The biomass of the mixtures never outperformed the biomass of the most productive clone, suggesting that clone identity is an important determinant of total biomass.The results indicate that the effects of genetic diversity on stand productivity may be transient and suggest that the conclusions of short-term studies on diversity effects should be evaluated carefully. They also suggest that individual clones are not complementary and that the properties of the stands are mainly additive results of the properties of the constituent clones.     

Automated egg-collecting and pupa-separator system for medfly mass-rearing facilities

The new automated egg-collecting system and pupa-separator device described here substantially reduces labour during medfly [ Ceratitis capitata (Wiedemann) (Diptera: Tephritidae)] mass production. The egg-collecting system gathers eggs dropping from the cage's oviposition net into a continuous stream of water, after which they accumulate in an egg-collecting sieve. The system provides an optimal environment for eggs, keeping them in a slow stream of well-oxygenated water. A pupa separator was designed to enable the separation of pupae from the pupation medium by sucking off the medium through a slowly moving sieving belt. The smaller particles of pupation medium are removed by a vacuum cleaner located under the circular sieving belt, and the pupae are collected in a collecting box. Quality control tests of the eggs collected and pupae separated have shown that neither system has a negative effect on the quality of the eggs or the pupae.     

Decrease of dehydrogenase activity of cerebral glyceraldehyde-3-phosphate dehydrogenase in different animal models of Alzheimer's disease

Recently, a relationship between glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and the β-amyloid precursor protein (βAPP) in relationship with the pathogenesis of Alzheimer's disease (AD) has been suggested. Therefore, we studied the specific activity of GAPDH in the different animal models of AD: transgenic mice (Tg2576) and rats treated with β-amyloid, or thiorphan, or lipopolysaccharides (LPS) and interferon γ (INFγ). We observed that GAPDH activity was significantly decreased in the brain samples from TG mice. The injection of β-amyloid, or thiorphan, an inhibitor of neprilysin involved in β-amyloid catabolism, in rat brains resulted in a pronounced reduction of the enzyme activity. The infusion of LPS and IFNγ, which can influence the progression of the AD, significantly reduced the enzyme activity.