@inproceedings{EngelMuellerMuelleretal.2013, author = {Engel, Tilman and M{\"u}ller, Juliane and M{\"u}ller, Steffen and Reschke, Antje and Kopinski, Stephan and Mayer, Frank}, title = {Validity and reliability of a new customised split-belt treadmill provoking unexpected walking perturbations}, series = {Medicine and science in sports and exercise : official journal of the American College of Sports Medicine}, volume = {45}, booktitle = {Medicine and science in sports and exercise : official journal of the American College of Sports Medicine}, number = {5}, publisher = {Lippincott Williams \& Wilkins}, address = {Philadelphia}, issn = {0195-9131}, pages = {462 -- 462}, year = {2013}, language = {en} } @article{BochMuellerPratiletal.2013, author = {Boch, Steffen and M{\"u}ller, J{\"o}rg and Pratil, Daniel and Blaser, Stefan and Fischer, Markus}, title = {Up in the tree - the overlooked richness of bryophytes and lichens in Tree Crowns}, series = {PLoS one}, volume = {8}, journal = {PLoS one}, number = {12}, publisher = {PLoS}, address = {San Fransisco}, issn = {1932-6203}, doi = {10.1371/journal.pone.0084913}, pages = {8}, year = {2013}, abstract = {Assessing diversity is among the major tasks in ecology and conservation science. In ecological and conservation studies, epiphytic cryptogams are usually sampled up to accessible heights in forests. Thus, their diversity, especially of canopy specialists, likely is underestimated. If the proportion of those species differs among forest types, plot-based diversity assessments are biased and may result in misleading conservation recommendations. We sampled bryophytes and lichens in 30 forest plots of 20 m x 20 m in three German regions, considering all substrates, and including epiphytic litter fall. First, the sampling of epiphytic species was restricted to the lower 2 m of trees and shrubs. Then, on one representative tree per plot, we additionally recorded epiphytic species in the crown, using tree climbing techniques. Per tree, on average 54\% of lichen and 20\% of bryophyte species were overlooked if the crown was not been included. After sampling all substrates per plot, including the bark of all shrubs and trees, still 38\% of the lichen and 4\% of the bryophyte species were overlooked if the tree crown of the sampled tree was not included. The number of overlooked lichen species varied strongly among regions. Furthermore, the number of overlooked bryophyte and lichen species per plot was higher in European beech than in coniferous stands and increased with increasing diameter at breast height of the sampled tree. Thus, our results indicate a bias of comparative studies which might have led to misleading conservation recommendations of plot-based diversity assessments.}, language = {en} } @inproceedings{KopinskiEngelMuelleretal.2013, author = {Kopinski, Stephan and Engel, Tilman and M{\"u}ller, Steffen and Mayer, Frank}, title = {Torque-EMG relationship of lower back muscles - a pilot study}, series = {Medicine and science in sports and exercise : official journal of the American College of Sports Medicine}, volume = {45}, booktitle = {Medicine and science in sports and exercise : official journal of the American College of Sports Medicine}, number = {5}, publisher = {Lippincott Williams \& Wilkins}, address = {Philadelphia}, issn = {0195-9131}, pages = {7 -- 8}, year = {2013}, language = {en} } @inproceedings{ReschkeMuellerMuelleretal.2013, author = {Reschke, Antje and M{\"u}ller, Juliane and M{\"u}ller, Steffen and Engel, Tilman and Mayer, Frank}, title = {Three-dimensional spine kinematics during perturbed treadmill walking - a pilot study}, series = {Medicine and science in sports and exercise : official journal of the American College of Sports Medicine}, volume = {45}, booktitle = {Medicine and science in sports and exercise : official journal of the American College of Sports Medicine}, number = {5}, publisher = {Lippincott Williams \& Wilkins}, address = {Philadelphia}, issn = {0195-9131}, pages = {172 -- 172}, year = {2013}, language = {en} } @article{FabianKunzMuelleretal.2013, author = {Fabian, Benjamin and Kunz, Steffen and M{\"u}ller, Sebastian and G{\"u}nther, Oliver}, title = {Secure federation of semantic information services}, series = {Decision support systems : DSS ; the international journal}, volume = {55}, journal = {Decision support systems : DSS ; the international journal}, number = {1}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0167-9236}, doi = {10.1016/j.dss.2012.05.049}, pages = {385 -- 398}, year = {2013}, abstract = {fundamental challenge for product-lifecycle management in collaborative value networks is to utilize the vast amount of product information available from heterogeneous sources in order to improve business analytics, decision support, and processes. This becomes even more challenging if those sources are distributed across multiple organizations. Federations of semantic information services, combining service-orientation and semantic technologies, provide a promising solution for this problem. However, without proper measures to establish information security, companies will be reluctant to join an information federation, which could lead to serious adoption barriers. Following the design science paradigm, this paper presents general objectives and a process for designing a secure federation of semantic information services. Furthermore, new as well as established security measures are discussed. Here, our contributions include an access-control enforcement system for semantic information services and a process for modeling access-control policies across organizations. In addition, a comprehensive security architecture is presented. An implementation of the architecture in the context of an application scenario and several performance experiments demonstrate the practical viability of our approach.}, language = {en} } @inproceedings{HainMuellerMuelleretal.2013, author = {Hain, Gerrit and M{\"u}ller, Juliane and M{\"u}ller, Steffen and Reschke, Antje and Mayer, Frank}, title = {Reliability of an in-vivo 3-segmental kinematic trunk model in a one-handed lifting task}, series = {Medicine and science in sports and exercise : official journal of the American College of Sports Medicine}, volume = {45}, booktitle = {Medicine and science in sports and exercise : official journal of the American College of Sports Medicine}, number = {5}, publisher = {Lippincott Williams \& Wilkins}, address = {Philadelphia}, issn = {0195-9131}, pages = {174 -- 174}, year = {2013}, language = {en} } @article{KoenigReschkeWolteretal.2013, author = {K{\"o}nig, Niklas and Reschke, Antje and Wolter, Martin and M{\"u}ller, Steffen and Mayer, Frank and Baur, Heiner}, title = {Plantar pressure trigger for reliable nerve stimulus application during dynamic H-reflex measurements}, series = {Gait \& posture}, volume = {37}, journal = {Gait \& posture}, number = {4}, publisher = {Elsevier}, address = {Clare}, issn = {0966-6362}, doi = {10.1016/j.gaitpost.2012.09.021}, pages = {637 -- 639}, year = {2013}, abstract = {In dynamic H-reflex measurements, the standardisation of the nerve stimulation to the gait cycle is crucial to avoid misinterpretation due to altered pre-synaptic inhibition. In this pilot study, a plantar pressure sole was used to trigger the stimulation of the tibialis nerve with respect to the gait cycle. Consequently, the intersession reliability of the soleus muscle H-reflex during treadmill walking was investigated. Seven young participants performed walking trials on a treadmill at 5 km/h. The stimulating electrode was placed on the tibial nerve in the popliteal fossa. An EMG was recorded from the soleus muscle. To synchronize the stimulus to the gait cycle, initial heel strike was detected with a plantar pressure sole. Maximum H-reflex amplitude and M-wave amplitude were obtained and the Hmax/Mmax ratio was calculated. Data reveals excellent reliability, ICC = 0.89. Test-retest variability was 13.0\% (+/- 11.8). The Bland-Altman analysis showed a systematic error of 2.4\%. The plantar pressure sole was capable of triggering the stimulation of the tibialis nerve in a reliable way and offers a simple technique for the evaluation of reflex activity during walking.}, language = {en} } @article{MuellerMuellerBauretal.2013, author = {M{\"u}ller, Juliane and M{\"u}ller, Steffen and Baur, Heiner and Mayer, Frank}, title = {Intra-individual gait speed variability in healthy children aged 1-15 years}, series = {Gait \& posture}, volume = {38}, journal = {Gait \& posture}, number = {4}, publisher = {Elsevier}, address = {Clare}, issn = {0966-6362}, doi = {10.1016/j.gaitpost.2013.02.011}, pages = {631 -- 636}, year = {2013}, abstract = {Introduction: Gait speed is one of the most commonly and frequently used parameters to evaluate gait development. It is characterized by high variability when comparing different steps in children. The objective of this study was to determine intra-individual gait speed variability in children. Methods: Gait speed measurements (6-10 trials across a 3 m walkway) were performed and analyzed in 8263 children, aged 1-15 years. The coefficient of variation (CV) served as a measure for intra-individual gait speed variability measured in 6.6 +/- 1.0 trials per child. Multiple linear regression analysis was conducted to evaluate the influence of age and body height on changes in variability. Additionally, a subgroup analysis for height within the group of 6-year-old children was applied. Results: A successive reduction in gait speed variability (CV) was observed for age groups (age: 1-15 years) and body height groups (height: 0.70-1.90 m). The CV in the oldest subjects was only one third of the CV (CV 6.25 +/- 3.52\%) in the youngest subjects (CV 16.58 +/- 10.01\%). Up to the age of 8 years (or 1.40 m height) there was a significant reduction in CV over time, compared to a leveling off for the older (taller) children. Discussion: The straightforward approach measuring gait speed variability in repeated trials might serve as a fundamental indicator for gait development in children. Walking velocity seems to increase to age 8. Enhanced gait speed consistency of repeated trials develops up to age 15.}, language = {en} } @article{SocherPratiBochetal.2013, author = {Socher, Stephanie A. and Prati, Daniel and Boch, Steffen and M{\"u}ller, J{\"o}rg and Baumbach, Henryk and Gockel, Sonja and Hemp, Andreas and Sch{\"o}ning, Ingo and Wells, Konstans and Buscot, Francois and Kalko, Elisabeth K. V. and Linsenmair, Karl Eduard and Schulze, Ernst-Detlef and Weisser, Wolfgang W. and Fischer, Markus}, title = {Interacting effects of fertilization, mowing and grazing on plant species diversity of 1500 grasslands in Germany differ between regions}, series = {Basic and applied ecology : Journal of the Gesellschaft f{\"u}r {\"O}kologie}, volume = {14}, journal = {Basic and applied ecology : Journal of the Gesellschaft f{\"u}r {\"O}kologie}, number = {2}, publisher = {Elsevier}, address = {Jena}, issn = {1439-1791}, doi = {10.1016/j.baae.2012.12.003}, pages = {126 -- 136}, year = {2013}, abstract = {The relationship of different types of grassland use with plant species richness and composition ( functional groups of herbs, legumes, and grasses) has so far been studied at small regional scales or comprising only few components of land use. We comprehensively studied the relationship between abandonment, fertilization, mowing intensity, and grazing by different livestock types on plant diversity and composition of 1514 grassland sites in three regions in North-East, Central and South-West Germany. We further considered environmental site conditions including soil type and topographical situation. Fertilized grasslands showed clearly reduced plant species diversity (-15\% plant species richness, -0.1 Shannon diversity on fertilized grasslands plots of 16m(2)) and changed composition (-3\% proportion of herb species), grazing had the second largest effects and mowing the smallest ones. Among the grazed sites, the ones grazed by sheep had higher than average species richness (+27\%), and the cattle grazed ones lower (-42\%). Further, these general results were strongly modulated by interactions between the different components of land use and by regional context: land-use effects differed largely in size and sometimes even in direction between regions. This highlights the importance of comparing different regions and to involve a large number of plots}, language = {en} } @article{BochPratiMuelleretal.2013, author = {Boch, Steffen and Prati, Daniel and M{\"u}ller, J{\"o}rg and Socher, Stephanie and Baumbach, Henryk and Buscot, Francois and Gockel, Sonja and Hemp, Andreas and Hessenm{\"o}ller, Dominik and Kalko, Elisabeth K. V. and Linsenmair, K. Eduard and Pfeiffer, Simone and Pommer, Ulf and Sch{\"o}ning, Ingo and Schulze, Ernst-Detlef and Seilwinder, Claudia and Weisser, Wolfgang W. and Wells, Konstans and Fischer, Markus}, title = {High plant species richness indicates management-related disturbances rather than the conservation status of forests}, series = {Basic and applied ecology : Journal of the Gesellschaft f{\"u}r {\"O}kologie}, volume = {14}, journal = {Basic and applied ecology : Journal of the Gesellschaft f{\"u}r {\"O}kologie}, number = {6}, publisher = {Elsevier}, address = {Jena}, issn = {1439-1791}, doi = {10.1016/j.baae.2013.06.001}, pages = {496 -- 505}, year = {2013}, abstract = {There is a wealth of smaller-scale studies on the effects of forest management on plant diversity. However, studies comparing plant species diversity in forests with different management types and intensity, extending over different regions and forest stages, and including detailed information on site conditions are missing. We studied vascular plants on 1500 20 m x 20 m forest plots in three regions of Germany (Schwabische Alb, Hainich-Dun, Schorfheide-Chorin). In all regions, our study plots comprised different management types (unmanaged, selection cutting, deciduous and coniferous age-class forests, which resulted from clear cutting or shelterwood logging), various stand ages, site conditions, and levels of management-related disturbances. We analyzed how overall richness and richness of different plant functional groups (trees, shrubs, herbs, herbaceous species typically growing in forests and herbaceous light-demanding species) responded to the different management types. On average, plant species richness was 13\% higher in age-class than in unmanaged forests, and did not differ between deciduous age-class and selection forests. In age-class forests of the Schwabische Alb and Hainich-Dun, coniferous stands had higher species richness than deciduous stands. Among age-class forests, older stands with large quantities of standing biomass were slightly poorer in shrub and light-demanding herb species than younger stands. Among deciduous forests, the richness of herbaceous forest species was generally lower in unmanaged than in managed forests, and it was even 20\% lower in unmanaged than in selection forests in Hainich-Dun. Overall, these findings show that disturbances by management generally increase plant species richness. This suggests that total plant species richness is not suited as an indicator for the conservation status of forests, but rather indicates disturbances.}, language = {en} }