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The aim of the study is the analysis of body composition, motor development and cardiovascular parameters of preschool-children. In 2001/2002 a longitudinal study started in 17 nursery schools in Berlin. A total of 160 children out of the 264 children participated in a regular exercise programme. After 24 months of training significant differences of body composition, motor skills and cardiovascular parameters between 5 complete year old children of the intervention and the control group were observed. The results show that such an exercise programme is successful as a preventive measure to decrease the risk of obesity.
Germination rates and germination fractions of seeds can be predicted well by the hydrothermal time (HTT) model. Its four parameters hydrothermal time, minimum soil temperature, minimum soil moisture, and variation of minimum soil moisture, however, must be determined by lengthy germination experiments at combinations of several levels of soil temperature and moisture. For some applications of the HTT model it is more important to have approximate estimates for many species rather than exact values for only a few species. We suggest that minimum temperature and variation of minimum moisture can be estimated from literature data and expert knowledge. This allows to derive hydrothermal time and minimum moisture from existing data from germination experiments with one level of temperature and moisture. We applied our approach to a germination experiment comparing germination fractions of wild annual species along an aridity gradient in Israel. Using this simplified approach we estimated hydrothermal time and minimum moisture of 36 species. Comparison with exact data for three species shows that our method is a simple but effective method for obtaining parameters for the HTT model. Hydrothermal time and minimum moisture supposedly indicate climate related germination strategies. We tested whether these two parameters varied with the climate at the site where the seeds had been collected. We found no consistent variation with climate across species, suggesting that variation is more strongly controlled by site-specific factors.Abstract auch auf deutsch vorhanden:Keimungsgeschwindigkeit und Anteil gekeimter Samen lassen sich gut mit dem Hydrothermalzeit-Modell bestimmen. Dessen vier Parameter Hydrothermalzeit, Mindesttemperatur, Mindestbodenfeuchte und Streuung der Mindestbodenfeuchte müssen jedoch durch aufwendige Keimungsversuche bei Kombinationen von mehreren Temperatur- und Feuchtigkeitsstufen bestimmt werden. Für manche Anwendungen des Hydrothermalzeit-Modells sind aber ungefähre Werte für viele Arten wichtiger als genaue Werte für wenige Arten. Wenn die Mindesttemperatur und die Streuung der Mindestfeuchte aus Veröffentlichungen und Expertenwissen geschätzt würde, können die Hydrothermalzeit und Mindestbodenfeuchte aus vorhandenen Daten von Keimungsversuchen mit nur einer Temperatur- und Feuchtigkeitsstufe berechnet werden. Wir haben unseren Ansatz auf einen Keimungsversuch zum Vergleich der Keimungsquote wilder einjähriger Arten entlang eines Trockenheitsgradienten in Israel angewendet. Mit diesem Ansatz bestimmten wir die Hydrothermalzeit und Mindestfeuchtigkeit von 36 Arten. Der Vergleich mit genauen Werten für drei Arten zeigt, dass mit unserem Ansatz Hydrothermalzeit-Parameter einfach und effektiv bestimmt werden können. Hydrothermalzeit und Mindestfeuchtigkeit sollten auch bestimmte klimabedingte Keimungsstrategien anzeigen. Deshalb testeten wir, ob diese zwei Parameter mit dem Klima am Ursprungsort der Samen zusammenhängen. Wir fanden jedoch keinen für alle Arten übereinstimmenden Zusammenhang, so dass die Unterschiede vermutlich stärker durch standörtliche als durch klimatische Ursachen hervorgerufen werden.
Investigation of the ectoparasitic fauna (Siphonaptera: Ischnopsyllidae; Diptera: Nycteribiidae; Heteroptera: Cimicidae) on bats in Brandenburg, Germany (part 2). The current investigation of bats in summer and winter quarters took place in addition to the study of Scheffler and Ressler (2005) and supplied new data for spreading and host spectrum of fleas and bat flies. With Penicillidia monoceros Speiser, 1900 on Myotis daubentoni a species of bat fly was found, which was not known in brandenburg (Germany) before. The proof of the flea species Nycteridopsylla longiceps Rothschild, 1908 at Pipistrellus pipistrellus is only the third detection in Brandenburg after 1911 and 1964. With Barbastella barbastellus the spectrum of examinated bats was extended. This species was parasitized by two flea species. On four species of bats also bugs (Heteroptera: Cimicidae)could be caught in summer quarters, which belong to the species Cimex dissimilis (Horvat, 1910). The causes of varying parasitizing rates with different species of fleas and bat flies are discussed.
Bemerkenswerte Pilzfunde auf der 37. Brandenburgischen Botanikertagung in Neuendorf bei Oranienburg
(2007)
Peridinin-chlorophyll a protein (PCP) is a unique water soluble antenna complex that employs the carotenoid peridinin as the main light-harvesting pigment. In the present study the near edge X-ray absorption fine structure (NEXAFS) spectrum of PCP was recorded at the carbon Kedge. Additionally, the NEXAFS spectra of the constituent pigments, chlorophyll a and peridinin, were measured. The energies of the lowest unoccupied molecular levels of these pigments appearing in the carbon NEXAFS spectrum were resolved. Individual contributions of the pigments and the protein to the measured NEXAFS spectrum of PCP were determined using a "building block" approach combining NEXAFS spectra of the pigments and the amino acids constituting the PCP apoprotein. The results suggest that absorption changes of the pigments in the carbon near K-edge region can be resolved following excitation using a suitable visible pump laser pulse. Consequently, it may be possible to study excitation energy transfer processes involving "optically dark" states of carotenoids in pigment-protein complexes by soft X-ray probe optical pump double resonance spectroscopy (XODR).
Extremophilic organisms are gaining increasing interest because of their unique metabolic capacities and great biotechnological potential. The unicellular acidophilic and mesothermophilic red alga Galdieria sulphuraria (074G) can grow autotrophically in light as well as heterotrophically in the dark. In this paper, the effects of externally added glucose on primary and secondary photosynthetic reactions are assessed to elucidate mixotrophic capacities of the alga. Photosynthetic O-2 evolution was quantified in an open system with a constant Supply Of CO2 to avoid rapid volatilization of dissolved inorganic carbon at low pH levels. In the presence of glucose, O-2 evolution was repressed even in illuminated cells. Ratios of variable to maximum chlorophyll fluorescence (F-v/F-m) and 77 Kfluorescence spectra indicated a reduced photochemical efficiency of photosystem II. The results were corroborated by strongly reduced levels of the photosystem 11 reaction centre protein D1. The downregulation of primary photosynthetic reactions was accompanied by reduced levels of the Calvin Cycle enzyme ribu lose-1,5-bisphosphate carboxylaselfoxygenase (Rubisco). Both effects depended on functional sugar uptake and are thus initiated by intracellular rather than extracellular glucose. Following glucose depletion, photosynthetic O-2 evolution of illuminated cells commenced after 15 h and Rubisco levels again reached the levels of autotrophic cells. It is concluded that true mixotrophy, involving electron transport across both photosystems, does not occur in G. sulphuraria 074G, and that heterotrophic growth is favoured over autotrophic growth if sufficient organic carbon is available.
Bacteria play a key role in the world's oceans, supporting nutrient remineralisation and mediating carbon transfer. Little is known about annual changes in bacterial concentration, production and metabolism during the extreme seasonal changes in biological productivity in Antarctic waters. We measured rates of bacterial production, concentrations of viruses and bacteria and environmental parameters between February 2004 and January 2005 at an Antarctic coastal site. Concentrations of total bacteria and viruses were obtained using 4', 6-diamidino-2- phenylindole (DAPI) and SYBR Green I (Molecular Probes), respectively. Populations of bacteria in different metabolic states were estimated using vital stains. Concentrations of bacteria with intact or compromised plasma membranes were estimated using BacLight (Molecular Probes) and active cells estimated using 6-carboxyfluorescein diacetate (6CFDA). Our study showed 6CFDA and BacLight gave rapid and ecologically valuable insights into bacterial physiology, production and growth in natural Antarctic communities that were poorly represented by changes in total cell concentrations. Concentrations of total, active and intact bacteria declined rapidly at the end of summer probably owing to viral infection and microheterotrophic grazing. The decline continued over winter, likely owing to substrate limitation, and concentrations only increased after the phytoplankton bloom in spring and summer. Bacterial abundance was positively correlated with particulate organic carbon (POC) and nitrogen (PON), but not dissolved organic carbon (DOC), reflecting the refractory nature of the DOC pool. Only active and intact bacteria were significantly correlated with concentrations of chl a and rates of bacterial production. Furthermore, the obtained rates of [H-3]thymidine uptake suggest that bacterial growth rates can be sustained by the populations identified as intact or by active cells alone.
Some aspects of the fungal flora in the Bol'Üoj Tha; area (NW-Caucasus) - During an excursion to the Bol'soj Tha; area in north-western Caucasus in the late summer of 1998 a number of mycological observations were made. 111 macrofungi species (30 ascomycetes, 81 basidiomycetes), 16 myxomycetes and 42 phytoparasitic fungi (15 Erysiphales, 27 Uredinales) were registered. The majority of the recorded macromycetes were decomposers of dead stems and logs of different trees and shrubs, especially of the dominating tree species Fagus orientalis and Abies nordmanniana. Bondarzewia montana, Hericium alpestre and Phellinus hartigii are typical colonisers of old Abies trunks and therefore of special interest. They were recorded several times, especially in the primeval forests of the excursion area. Some of the collected taxa like Daldinia petriniae, Hypoxylon cercidicola, H. liviae, Ophiostoma polyporicola, Pezoloma marchantiae, Ramsbottomia macracantha, Symphyosyria angelicae, Auriporia aurulenta, Flagelloscypha pilatii, Hymenochaete carpatica, Marasmius cf. rhododendrorum and Pellidiscus pallidus are discussed in detail. Some of the recorded taxa are probably new for the western Caucasus and in some cases also for Russia.
The list contains all the identified fungi collections of the excursion in 1998. In it were also included some records published by OTTO (2001) and few unpublished data of fungi mainly collected by V. Otte after 1998. Unless other information is given, all the fungal collections and their determination were done by the author. Most of the collections are integrated as exsiccata in the herbarium of the author.
Bacterivory by mixotrophic flagellates may contribute to their nutrient supply, providing a competitive advantage in oligotrophic waters. We hypothesized an increase in Dinobryon biomass during the re-oligotrophication process in the large and deep Lake Constance. To estimate whether bacterivory contributed substantially to the flagellates' phosphorus supply, we determined ingestion rates. Dinobryon biomass increased with decreasing total phosphorus concentrations in the lake over a period of 17 years (P = 0.0005). The promotion of Dinobryon biomass during re-oligotrophication may be explained by the increasing light availability due to the decreasing biomass of other phytoplankton yielding a release from competition. The date of the Dinobryon abundance maximum shifted to earlier time points in the year, probably because a smaller phosphorus pool was depleted more quickly. Ingestion rates of Dinobryon ranged between 0.5 and 13 bacteria cell(-1) h(-1) (0.2-5.4 fg C pg C-1 h(-1)), and clearance rates varied between 0.2 and 3.2 nL cell(-1) h(-1) (4-78 pL pg C-1 h(-1)), leading to bacterial losses of up to 30% day(-1) of bacterial standing stock. The ingestion of bacteria covered 77% of the phosphorus need of the flagellate during the period of maximum growth in 1996 (net growth rate 0.34 day(-1)), and it fully covered the need at all other times.