267 research outputs found
Similarities in social calls during autumn swarming may facilitate interspecific communication between Myotis bat species
Bats employ a variety of social calls for communication purposes. However, for most species, social calls are far less studied than echolocation calls and their specific function often remains unclear. We investigated the function of in-flight social calls during autumn swarming in front of a large hibernaculum in Northern Germany, whose main inhabitants are two species of Myotis bats, Nattererâs bats (Myotis nattereri) and Daubentonâs bats (Myotis daubentonii). We recorded social calls in nights of high swarming activity and grouped the calls based on their spectro-temporal structure into ten types and verified our visual classification by a discriminant function analysis. Whenever possible, we subsequently assigned social calls to either M. daubentonii or M. nattereri by analyzing the echolocation calls surrounding them. As many bats echolocate at the same time during swarming, we did not analyze single echolocation calls but the âsoundscapeâ surrounding each social call instead, encompassing not only spectral parameters but also the timbre (vocal âcolorâ) of echolocation calls. Both species employ comparatively similar social call types in a swarming context, even though there are subtle differences in call parameters between species. To additionally gain information about the general function of social calls produced in a swarming context, we performed playback experiments with free-flying bats in the vicinity of the roost, using three different call types from both species, respectively. In three out of six treatments, bat activity (approximated as echolocation call rate) increased during and after stimulus presentation, indicating that bats inspected or approached the playback site. Using a camera trap, we were sometimes able to identify the species of approaching bats. Based on the photos taken during playbacks, we assume one call type to support interspecific communication while another call type works for intraspecific group cohesion
Microplastic fiber and drought effects on plants and soil are only slightly modified by arbuscular mycorrhizal fungi
Microplastics are increasingly recognized as a factor of global change. By altering soil inherent properties and processes, ripple-on effects on plants and their symbionts can be expected. Additionally, interactions with other factors of global change, such as drought, can influence the effect of microplastics. We designed a greenhouse study to examine effects of polyester microfibers, arbuscular mycorrhizal (AM) fungi and drought on plant, microbial and soil responses. We found that polyester microfibers increased the aboveground biomass of Allium cepa under well-watered and drought conditions, but under drought conditions the AM fungal-only treatment reached the highest biomass. Colonization with AM fungi increased under microfiber contamination, however, plant biomass did not increase when both AM fungi and fibers were present. The mean weight diameter of soil aggregates increased with AM fungal inoculation overall but decreased when the system was contaminated with microfibers or drought stressed. Our study adds additional support to the mounting evidence that microplastic fibers in soil can affect the plant-soil system by promoting plant growth, and favoring key root symbionts, AM fungi. Although soil aggregation is usually positively influenced by plant roots and AM fungi, and microplastic promotes both, our results show that plastic still had a negative effect on soil aggregates. Even though there are concerns that microplastic might interact with other factors of global change, our study revealed no such effect for drought
The soundscape of swarming: Proof of concept for a noninvasive acoustic species identification of swarming Myotis bats
Bats emit echolocation calls to orientate in their predominantly dark environment. Recording of speciesâspecific calls can facilitate species identification, especially when mist netting is not feasible. However, some taxa, such as Myotis bats can be hard to distinguish acoustically. In crowded situations where calls of many individuals overlap, the subtle differences between species are additionally attenuated. Here, we sought to noninvasively study the phenology of Myotis bats during autumn swarming at a prominent hibernaculum. To do so, we recorded sequences of overlapping echolocation calls (NÂ =â564) during nights of high swarming activity and extracted spectral parameters (peak frequency, start frequency, spectral centroid) and linear frequency cepstral coefficients (LFCCs), which additionally encompass the timbre (vocal âcolorâ) of calls. We used this parameter combination in a stepwise discriminant function analysis (DFA) to classify the call sequences to species level. A set of previously identified call sequences of single flying Myotis daubentonii and Myotis nattereri, the most common species at our study site, functioned as a training set for the DFA. 90.2% of the call sequences could be assigned to either M. daubentonii or M. nattereri, indicating the predominantly swarming species at the time of recording. We verified our results by correctly classifying the second set of previously identified call sequences with an accuracy of 100%. In addition, our acoustic species classification corresponds well to the existing knowledge on swarming phenology at the hibernaculum. Moreover, we successfully classified call sequences from a different hibernaculum to species level and verified our classification results by capturing swarming bats while we recorded them. Our findings provide a proof of concept for a new noninvasive acoustic monitoring technique that analyses âswarming soundscapesâ by combining classical acoustic parameters and LFCCs, instead of analyzing single calls. Our approach for species identification is especially beneficial in situations with multiple calling individuals, such as autumn swarming
Adaptionsbarrieren im Technologietransfer â Begriff, Relevanz und Implikationen fĂŒr das Marketing
Der Erfolg eines Technologietransfers hĂ€ngt unter anderem von der Bereitschaft und FĂ€higkeit potenzieller Anwender zur Akzeptanz der zu transferierenden Technologie ab. WĂ€hrend die Literatur dem Prozess des Technologietransfers groĂe Aufmerksamkeit widmet, gibt es vergleichsweise wenige Erkenntnisse zum Management von Akzeptanzbarrieren und KommunikationsmaĂnahmen zur BewĂ€ltigung dieser Barrieren. Ziel des vorliegenden Beitrags ist es, diese Barrieren nĂ€her zu untersuchen und Kommunikationsinhalte und -instrumente zu betrachten, die diese Barrieren wirkungsvoll ĂŒberwinden helfen. Der vorliegende Beitrag diskutiert daher den Stand der Literatur zur Adaption von Innovationen und zur Förderung einer Innovationsadaption durch Kommunikationsinhalte und -instrumente. Am Beispiel einer neuartigen FĂŒgetechnologie werden MaĂnahmen fĂŒr eine zielgerichtete Vermittlung von Informationen zur Förderung ihrer Adaption durch potenzielle Anwender dargestellt. Der Beitrag endet mit einer Zusammenfassung und einem Ausblick auf weitere Forschungsfragen
In vivo load measurements with instrumented implants
Aquatic exercises are widely used for rehabilitation or preventive therapies
in order to enable mobilization and muscle strengthening while minimizing
joint loading of the lower limb. The load reducing effect of water due to
buoyancy is a main advantage compared to exercises on land. However, also drag
forces have to be considered that act opposite to the relative motion of the
body segments and require higher muscle activity. Due to these opposing
effects on joint loading, the load-reducing effect during aquatic exercises
remains unknown. The aim of this study was to quantify the joint loads during
various aquatic exercises and to determine the load reducing effect of water.
Instrumented knee and hip implants with telemetric data transfer were used to
measure the resultant joint contact forces in 12 elderly subjects (6x hip, 6x
knee) in vivo. Different dynamic, weight-bearing and non-weight-bearing
activities were performed by the subjects on land and in chest-high water.
Non-weight-bearing hip and knee flexion/extension was performed at different
velocities and with additional Aquafins. Joint forces during aquatic exercises
ranged between 32 and 396% body weight (BW). Highest forces occurred during
dynamic activities, followed by weight-bearing and slow non-weight-bearing
activities. Compared to the same activities on land, joint forces were reduced
by 36â55% in water with absolute reductions being greater than 100%BW during
weight-bearing and dynamic activities. During non-weight-bearing activities,
high movement velocities and additional Aquafins increased the joint forces by
up to 59% and resulted in joint forces of up to 301%BW. This study confirms
the load reducing effect of water during weight-bearing and dynamic exercises.
Nevertheless, high drag forces result in increased joint contact forces and
indicate greater muscle activity. By the choice of activity, movement velocity
and additional resistive devices joint forces can be modulated individually in
the course of rehabilitation or preventive therapies
Effects of microplastics on crop nutrition in fertile soils and interaction with arbuscular mycorrhizal fungi
Introduction
Soil microplastic (MP) pollution has emerged as a main factor of global change, but its effects on soil nutrient availability and uptake by crops (macro and micronutrients) are largely unknown. Arbuscular mycorrhizal fungi (AMF) are regulators of nutrient availability and uptake and can interact with soil MP.
Materials and Methods
Building on previous studies, here we explored in a 50-days pot experiment the influence and interaction of MP fibres (0.4%) and commercial AMF in soil and onion chemistry, that is, in elemental composition of onion shoots and soils (C, N, Ca, Mg, K, P, S, Cu, Fe, Mn and Zn) and micronutrient soil availability (Cu, Fe, Mn and Zn).
Results
MP had detrimental effects on K, Mg and S, but increased the soil availability of Zn and shoot uptake. AMF inoculation buffered the effects of MP by balancing/enhancing nutrient availability and plant uptake. Particularly, the commercial AMF inoculum remarkably enhanced Mn uptake by onion.
Conclusion
Our results support the use of AMF to sustainably manage agricultural ecosystems contaminated with MP, buffering and counteracting the effects of MP by balancing nutrient availability and plant uptake
Extended half-life target module for sustainable UniCAR T-cell treatment of STn-expressing cancers
Background: Adapter chimeric antigen receptor (CAR) approaches have emerged has promising strategies to increase clinical safety of CAR T-cell therapy. In the UniCAR system, the safety switch is controlled via a target module (TM) which is characterized by a small-size and short half-life. The rapid clearance of these TMs from the blood allows a quick steering and self-limiting safety switch of UniCAR T-cells by TM dosing. This is mainly important during onset of therapy when tumor burden and the risk for severe side effects are high. For long-term UniCAR therapy, the continuous infusion of TMs may not be an optimal setting for the patients. Thus, in later stages of treatment, single infusions of TMs with an increased half-life might play an important role in long-term surveillance and eradication of residual tumor cells. Given this, we aimed to develop and characterize a novel TM with extended half-life targeting the tumor-associated carbohydrate sialyl-Tn (STn). Methods: The extended half-life TM is composed of the STn-specific single-chain variable fragment (scFv) and the UniCAR epitope, fused to the hinge region and Fc domain of a human immunoglobulin 4 (IgG4) antibody. Specific binding and functionality of the αSTn-IgG4 TM as well as pharmacokinetic features were assessed using in vitro and in vivo assays and compared to the already established small-sized αSTn TM. Results: The novel αSTn-IgG4 TM efficiently activates and redirects UniCAR T-cells to STn-expressing tumors in a target-specific and TM-dependent manner, thereby promoting the secretion of proinflammatory cytokines and tumor cell lysis in vitro and in experimental mice. Moreover, PET-imaging results demonstrate the specific enrichment of the αSTn-IgG4 TM at the tumor site, while presenting a prolonged serum half-life compared to the short-lived αSTn TM. Conclusion: In a clinical setting, the combination of TMs with different formats and pharmacokinetics may represent a promising strategy for retargeting of UniCAR T-cells in a flexible, individualized and safe manner at particular stages of therapy. Furthermore, as these molecules can be used for in vivo imaging, they pose as attractive candidates for theranostic approaches.publishersversionpublishe
- âŠ