Expert range maps of global mammal distributions harmonised to three taxonomic authorities

AimComprehensive, global information on species' occurrences is an essential biodiversity variable and central to a range of applications in ecology, evolution, biogeography and conservation. Expert range maps often represent a species' only available distributional information and play an increasing role in conservation assessments and macroecology. We provide global range maps for the native ranges of all extant mammal species harmonised to the taxonomy of the Mammal Diversity Database (MDD) mobilised from two sources, the Handbook of the Mammals of the World (HMW) and the Illustrated Checklist of the Mammals of the World (CMW).LocationGlobal.TaxonAll extant mammal species.MethodsRange maps were digitally interpreted, georeferenced, error-checked and subsequently taxonomically aligned between the HMW (6253 species), the CMW (6431 species) and the MDD taxonomies (6362 species).ResultsRange maps can be evaluated and visualised in an online map browser at Map of Life (mol.org) and accessed for individual or batch download for non-commercial use.Main conclusionExpert maps of species' global distributions are limited in their spatial detail and temporal specificity, but form a useful basis for broad-scale characterizations and model-based integration with other data. We provide georeferenced range maps for the native ranges of all extant mammal species as shapefiles, with species-level metadata and source information packaged together in geodatabase format. Across the three taxonomic sources our maps entail, there are 1784 taxonomic name differences compared to the maps currently available on the IUCN Red List website. The expert maps provided here are harmonised to the MDD taxonomic authority and linked to a community of online tools that will enable transparent future updates and version control

Dilution and the theoretical description of growth-rate dependent gene expression

Expression of a gene is not only tuned by direct regulation, but also affected by the global physiological state of the (host) cell. This global dependence complicates the quantitative understanding of gene regulation and the design of synthetic gene circuits. In bacteria these global effects can often be described as a dependence on the growth rate. Here we discuss how growth-rate dependence can be incorporated in mathematical models of gene expression by comparing data for unregulated genes with the predictions of different theoretical descriptions of growth-rate dependence. We argue that a realistic description of growth effects requires a growth-rate dependent protein synthesis rate in addition to dilution by growth

Swimming patterns of a polarly flagellated bacterium in environments of increasing complexity

The natural habitat of many bacterial swimmers is dominated by interfaces and narrow interstitial spacings where they frequently interact with the fluid boundaries in their vicinity. To quantify these interactions, we investigated the swimming behavior of the soil bacterium Pseudomonas putida in a variety of confined environments. Using microfluidic techniques, we fabricated structured microchannels with different configurations of cylindrical obstacles. In these environments, we analyzed the swimming trajectories for different obstacle densities and arrangements. Although the overall swimming pattern remained similar to movement in the bulk fluid, we observed a change in the turning angle distribution that could be attributed to collisions with the cylindrical obstacles. Furthermore, a comparison of the mean run length of the bacteria to the mean free path of a billiard particle in the same geometry indicated that, inside a densely packed environment, the trajectories of the bacterial swimmers are efficiently guided along the open spacings

Verfahren zur elektrochemischen Analyse

The invention relates to a process for the electrochemmical analysis of solutions, as used, for example, in chemical analysis or for checking purposes in industry and environmental engineering. Individual substances are detected by depositing them on electrodes followed by detection of the deposited substances. Whereas, in known processes, all the substances to be detected are deposited on an electrode and detected one after the other, in the process according to the invention, numerous electrodes are used. The substances to be detected are deposited from the solution simultaneously onto these electrodes in such a way that every electrode receives the deposit of a different substance or a different substance mixture. Then the deposited substances are detected simultaneously on each of the electrodes. This drastically shortens the measuring time and the risk of incorrect measurements is greatly reduced due to interactions between the substances to be detected on the electrodes

Analyzing the spatial positioning of nuclei in polynuclear giant cells

How cells establish and maintain a well-defined size is a fundamental question of cell biology. Here we investigated to what extent the microtubule cytoskeleton can set a predifined cell size, independent of an enclosing cell membrane. We used electropulse-induced cell fusion to form giant multinuclear cells of the social amoeba Dictyostelium discoideum. Based on dual-color confocal imaging of cells that expressed fluorescent markers for the cell nucleus and the microtubules, we determined the subcellular distributions of nuclei and centrosomes in the giant cells. Our two- and three-dimensional imaging results showed that the positions of nuclei in giant cells do not fall onto a regular lattice. However, a comparison with model predictions for random positioning showed that the subcellular arrangement of nuclei maintains a low but still detectable degree of ordering. This can be explained by the steric requirements of the microtubule cytoskeleton, as confirmed by the effect of a microtubule degrading drug.13

Use of interdigitated microelectrode arrays as amperometric transducers and amplifier

An array of six interdigitated thin film platinum microelectrodes made by silicon technology and special analytical procedures will be described. For the analytical use as basic transducer the microelectrode array consists of an assembly of independent microband electrodes. Each microband electrode is 3 Mym width, 1 mm long with an interelectrode space of 1 Mym. The other area is insulated by a silicon nitride layer. The microband electrodes are independently held at desired potentials by means of an recently developed multipotentiostat. Applying the oxidation and the reduction potential of electron mediators to pairs of the interdigitated electrodes a redox cyclisation producing an electrochemical amplification have been realised. This could be demonstrated for the sensitive detection of the reversible redox coupe ferro/ferri cyanide. On the other hand, when the same potential is applied at each electrode of an array, the signal to noise ratio is increased due to a signal accumulation . As a result the measurement can be performed with a better reproducibility. These measuring principles can be attractive for improvement of biosensing in microsystem technology