Estimating extreme daily pollen loads for Szeged, Hungary using previous-day meteorological variables

The aim of this paper is to analyse how meteorological elements relate to extreme Ambrosia pollen load on the one hand and to extreme total pollen load excluding Ambrosia pollen on the other for Szeged, Southern Hungary. The data set comes from a 9-year period (1999–2007) and includes previous-day means of five meteorological variables and actual-day values of the two pollen variables. Factor analysis with special transformation was performed on the meteorological and pollen load data in order to find out the strength and direction of the association of the meteorological and pollen variables. Then, using selected low and high quantiles corresponding to probability distributions of Ambrosia pollen and the remaining pollen loads, the quantile and beyond-quantile averages of pollen loads were compared and evaluated. Finally, a nearest neighbour (NN) technique was applied to discriminate between extreme and non-extreme pollen events using meteorological elements as explaining variables. The observed below or above quantile events are compared with events obtained from NN decisions. The number of events exceeding the quantile of 90% and not exceeding that of 10% is strongly underestimated. However, the procedure works well for quantiles of 20 and 80%, and even better for those of 30 and 70%. Using a nearest neighbour technique, explaining variables in decreasing order of their influence on Ambrosia pollen load are temperature, global solar flux, relative humidity, air pressure and wind speed, while on the load of the remaining pollen are temperature, relative humidity, global solar flux, air pressure and wind speed.     

Purifying selection shaping the evolution of the Toll-like receptor 2 TIR domain in brown hares (Lepus europaeus) from Europe and the Middle East

Molecular Biology Reports - Toll-like receptors (TLRs) are transmembrane proteins of the innate immune system, composed of the ectodomain involved in pathogen recognition and the intracellular...     

Eine Doppelkapsel vonCatharinaea tenella aus Steiermark

Ohne Zusammenfassung     

A synthesis of l-ristosamine and a derivative of its C-4 epimer

A synthesis of l-ristosamine from l-rhamnal is described, involving the sequence of reactions: methoxymercuration, tosylation, azide displacement, and reduction, which gave methyl α-l-ristosaminide (10). Acid hydrolysis then afforded l-ristosamine hydrochloride. Trifluoroacetylation of the hydrochloride of 10 followed by saponification and oxidation with ruthenium tetraoxide gave methyl 2,3,6-tri-deoxy-3-trifluoroacetamido-α-l-erythro-hexopyranosid-4-ulose (17). Borohydride reduction of 17 gave a separable, 1:1 mixture of methyl 2,3,6-trideoxy-3-trifluoroacetamido-α-l-ribo- and α-l-xylo-hexopyranoside.     

Scavenger-driven fish carcass decomposition and phosphorus recycling: Laboratory experiments with freshwater fish and crayfish

1. Fish carcass decomposition can generate fluxes of nutrients to the water column at levels comparable to other major nutrient sources. However, relatively little is known about the biological processes modulating fish decay or the rates at which carcass-bound nutrients are made available to the biota.
2. This study focused on quantifying scavenger-mediated phosphorus (P) recycling, because the availability of this essential element can regulate the trophic state of aquatic ecosystems.
3. To explore the role of some important macroscopic aquatic scavengers in P recycling, laboratory experiments were conducted where carcasses of two fish species (common bleak Alburnus alburnus; pumpkinseed Lepomis gibbosus) were offered to two size classes of black bullhead (Ameiurus melas) and two crustacean species (spiny-cheek crayfish Faxonius limosus; narrow-clawed crayfish Astacus leptodactylus).
4. Our results show that the black bullhead and the two crayfish species are highly efficient macroscopic decomposers as the P contents of scavenged carcasses were reduced at significantly higher rates compared to those of microbially decomposed (control) carcasses.
5. Pumpkinseed carcasses proved to be more resistant to rapid decomposition, as they typically lost lower proportions of their P content than bleak carcasses during the course of the experiments.
6. Scavengers sequestered a relatively large fraction (up to 33% in black bullhead and 36% in crayfish) of total carcass P in their bodies. This suggests that the consumer species used in this study can transfer/return considerable quantities of carcass-derived nutrients directly to higher trophic levels incorporated into their own tissues, and may serve as an additional, short-term sink of these nutrients.

     

Elemental Analysis of Human Blood Serum by Microwave Plasma—Investigation of the Matrix Effects Caused by Sodium Using Model Solutions

Biological Trace Element Research - Human blood is a complex sample matrix when elemental analysis is considered. In this study, the effects of Na, a natural component of serum samples, was...     

Drosophila Nimrod proteins bind bacteria

Engulfment of foreign particles by phagocytes is initiated by the engagement of phagocytic receptors. We have previously reported that NimC1 is involved in the phagocytosis of bacteria in Drosophila melanogaster. We have identified a family of genes, the Nimrod gene superfamily, encoding characteristic NIM domain containing structural homologues of NimC1. In this work we studied the bacterium-binding properties of the Nimrod proteins by using a novel immunofluorescencebased flow cytometric assay. This method proved to be highly reproducible and suitable for investigations of the bacteriumbinding capacities of putative phagocytosis receptors. We found that NimC1, NimA, NimB1 and NimB2 bind bacteria significantly but differently. In this respect they are similar to other NIM domain containing receptors Eater and Draper.     

Colony size,nestmate density and social history shape behavioural variation in Formica fusca colonies

In ants, individuals live in tightly integrated units (colonies) and work collectively for its success. In such groups, stable intraspecific variation in behaviour within or across contexts (personality) can occur at two levels: individuals and colonies. This paper examines how colony size and nestmate density influence the collective exploratory behaviour of Formica fusca (Hymenoptera: Formicidae), in the laboratory. The housing conditions of the colonies were manipulated to vary the size of colonies and their densities under a fully factorial design. The results demonstrate the presence of colony behavioural repeatability in this species, and contrary to our expectations, colonies were more explorative on average when they were kept at lower nestmate densities. We also found that experimental colonies created from larger source colonies were more explorative, which conveys that a thorough understanding of the contemporary behaviour of a colony may require knowing its social history and how it was formed. Our results also convey that the colony size and nestmate density can have significant effects on the exploratory behaviour of ant colonies.     

Diuretic treatment affects the length of torpor bouts in hibernating European ground squirrels (Spermophilus citellus)

During the hibernation season, hibernating mammals show a sequence of torpor bouts that are interrupted by periodic arousals and brief normothermic periods. The functional significance of periodic arousals is still uncertain. We hypothesized that the imbalances in water economy may play a role in the timing of periodic arousals in hibernating species. We applied furosemide, a diuretic drug, to assess whether hibernating European ground squirrels respond to elevated urine production by shortening their torpor bouts. Urine production in the treated squirrels increased and led to more frequent arousals, presumably to restore water balance by recovery of lost water from blood and tissues. The length of the subsequent normothermic phase was not affected by the diuretic treatment. Body mass change correlated primarily with the amount of voided urine. Although our study did not identify the underlying mechanism, our results support the view that water economy, and water loss may play a role in the timing of periodic arousals.