1,161 research outputs found
Ermittlung der FutterqualitĂ€t verschiedener Wintererbsengenotypen in Rein- und Gemengesaat zur Nutzung als nachwachsender Rohstoff, als GrĂŒnfutter und als Druschfrucht
NormalblĂ€ttrige Wintererbsen sind in Reinsaat eine rohproteinreiche Winterzwischenfrucht fĂŒr die Nutzung als GrĂŒnfutter oder als nachwachsender Rohstoff zur Energiegewinnung im Rahmen von Zweikulturnutzungssystemen. Zum Korndrusch im Gemengeanbau stellen sie bei mindestens vergleichbaren KornertrĂ€gen und QualitĂ€ten eine Alternative zu Sommererbsen dar. Dabei können Anbauprobleme von Sommererbsen besonders hinsichtlich der Unkrautregulierung reduziert werden
Widespread bone-based fluorescence in chameleons
Fluorescence is widespread in marine organisms but uncommon in terrestrial tetrapods. We here show that many chameleon species have bony tubercles protruding from the skull that are visible through their scales, and fluoresce under UV light. Tubercles arising from bones of the skull displace all dermal layers other than a thin, transparent layer of epidermis, creating a 'window' onto the bone. In the genus Calumma, the number of these tubercles is sexually dimorphic in most species, suggesting a signalling role, and also strongly reflects species groups, indicating systematic value of these features. Co-option of the known fluorescent properties of bone has never before been shown, yet it is widespread in the chameleons of Madagascar and some African chameleon genera, particularly in those genera living in forested, humid habitats known to have a higher relative component of ambient UV light. The fluorescence emits with a maximum at around 430 nm in blue colour which contrasts well to the green and brown background reflectance of forest habitats. This discovery opens new avenues in the study of signalling among chameleons and sexual selection factors driving ornamentation
20 Jahre âGĂ€a e.V. - Vereinigung ökologischer Landbauâ
For the understanding of ecological agriculture, knowledge of its roots is essential.
Actual literature about this topic does not cover the history of ecological agriculture in
East Germany especially if chronological development and individual motivation are
seen as mutual dependent. The ecological organisation GĂ€a e.V. was founded in the
GDR in 1989. Its origins were oppositional environmental groups working within the
East German church. It developed own principles based on individual experience with
unique aspects. It has established and integrated well in the German ecological agriculture
structure after the reunification and the changed political background as an
authentic representative of and for the East German ecological agriculture scene
Insulin-like growth factor 1 stimulates the angiogenic activity of adipose tissue-derived microvascular fragments
Angiogenesis in adipose tissue is promoted by insulin-like growth factor 1 signaling. We analyzed whether this regulatory mechanism also improves the angiogenic activity of adipose tissue-derived microvascular fragments. Murine adipose tissue-derived microvascular fragments were cultivated for 24âh in the University of Wisconsin (UW) solution supplemented with vehicle, insulin-like growth factor 1, or a combination of insulin-like growth factor 1 and insulin-like growth factor-binding protein 4. Subsequently, we assessed their cellular composition, viability, proliferation, and growth factor expression. Moreover, cultivated adipose tissue-derived microvascular fragments were seeded onto collagen-glycosaminoglycan scaffolds, which were implanted into dorsal skinfold chambers to study their vascularization and incorporation. Insulin-like growth factor 1 increased the viability and growth factor expression of adipose tissue-derived microvascular fragments without affecting their cellular composition and proliferation. Accordingly, scaffolds containing insulin-like growth factor 1-stimulated adipose tissue-derived microvascular fragments exhibited an enhanced in vivo vascularization and incorporation. These positive insulin-like growth factor 1 effects were reversed by additional exposure of adipose tissue-derived microvascular fragments to insulin-like growth factor-binding protein 4. Our findings indicate that insulin-like growth factor 1 stimulation of adipose tissue-derived microvascular fragments is suitable to improve their vascularization capacity
Dynamic and volumetric variables reliably predict fluid responsiveness in a porcine model with pleural effusion
Background: The ability of stroke volume variation (SVV), pulse pressure variation (PPV) and global end-diastolic volume (GEDV) for prediction of fluid responsiveness in presence of pleural effusion is unknown. The aim of the present study was to challenge the ability of SVV, PPV and GEDV to predict fluid responsiveness in a porcine model with pleural effusions.
Methods: Pigs were studied at baseline and after fluid loading with 8 ml kgâ1 6% hydroxyethyl starch. After withdrawal of 8 ml kgâ1 blood and induction of pleural effusion up to 50 ml kgâ1 on either side, measurements at baseline and after fluid loading were repeated. Cardiac output, stroke volume, central venous pressure (CVP) and pulmonary occlusion pressure (PAOP) were obtained by pulmonary thermodilution, whereas GEDV was determined by transpulmonary thermodilution. SVV and PPV were monitored continuously by pulse contour analysis.
Results: Pleural effusion was associated with significant changes in lung compliance, peak airway pressure and stroke volume in both responders and non-responders. At baseline, SVV, PPV and GEDV reliably predicted fluid responsiveness (area under the curve 0.85 (p<0.001), 0.88 (p<0.001), 0.77 (p = 0.007). After induction of pleural effusion the ability of SVV, PPV and GEDV to predict fluid responsiveness was well preserved and also PAOP was predictive. Threshold values for SVV and PPV increased in presence of pleural effusion.
Conclusions: In this porcine model, bilateral pleural effusion did not affect the ability of SVV, PPV and GEDV to predict fluid responsiveness
On the potential of augmented reality for mathematics teaching with the application cleARmaths
Learning content in mathematics, such as vector geometry, is still predominantly taught in an abstract manner, as the visualization and interaction of three-dimensional problems are limited with classical forms of teaching such as blackboard lessons or exercise sheets. This research article proposes the use of augmented reality (AR) in mathematics education. The proposed approach aims at easing the learning process related to vector geometry currently taught in senior mathematics classes by using intuitive visualization. The article introduces the concept of AR and presents the didactic foundations and the influence on the learning process based on an extensive literature review. Although studies see great potential in the use of AR for teaching mathematics, the method has so far hardly been used in schools. This can be mainly explained by the technological entry barrier of AR and the lack of simple, robust AR applications, in particular for vector geometry. To fill this gap, the authors developed âcleARmathsâ, a developed android application for augmented reality-based teaching in vector geometry that allows widespread use. As a didactical concept, some example exercises sessions with the app are proposed, demonstrating how the app could be used in a mathematics classroom. Finally, the app was evaluated in a mathematics class and the results analyzed in a detailed study. It was found by the teacher and students to be beneficial and amusing, demonstrating the potential for AR in mathematics classes
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Unraveling the Mechanism and Kinetics of Binding of an LCI-eGFP-Polymer for Antifouling Coatings
The ability of proteins to adsorb irreversibly onto surfaces opens new possibilities to functionalize biological interfaces. Herein, the mechanism and kinetics of adsorption of protein-polymer macromolecules with the ability to equip surfaces with antifouling properties are investigated. These macromolecules consist of the liquid chromatography peak I peptide from which antifouling polymer brushes are grafted using single electron transfer-living radical polymerization. Surface plasmon resonance spectroscopy reveals an adsorption mechanism that follows a Langmuir-type of binding with a strong binding affinity to gold. X-ray reflectivity supports this by proving that the binding occurs exclusively by the peptide. However, the lateral organization at the surface is directed by the cylindrical eGFP. The antifouling functionality of the unimolecular coatings is confirmed by contact with blood plasma. All coatings reduce the fouling from blood plasma by 8894% with only minor effect of the degree of polymerization for the studied range (DP between 101 and 932). The excellent antifouling properties, combined with the ease of polymerization and the straightforward coating procedure make this a very promising antifouling concept for a multiplicity of applications
Galaxies undergoing ram-pressure stripping: the influence of the bulge on morphology and star formation rate
We investigate the influence of stellar bulges on the star formation and
morphology of disc galaxies that suffer from ram pressure. Several tree-SPH
(smoothed particle hydrodynamics) simulations have been carried out to study
the dependence of the star formation rate on the mass and size of a stellar
bulge. In addition, different strengths of ram pressure and different
alignments of the disc with respect to the intra-cluster medium (ICM) are
applied. As claimed in previous works, when ram pressure is acting on a galaxy,
the star formation rate (SFR) is enhanced and rises up to four times with
increasing ICM density compared to galaxies that evolve in isolation. However,
a bulge suppresses the SFR when the same ram pressure is applied. Consequently,
fewer new stars are formed because the SFR can be lowered by up to 2 M_sun/yr.
Furthermore, the denser the surrounding gas, the more inter-stellar medium
(ISM) is stripped. While at an ICM density of 10^-28 g/cm^3 about 30% of the
ISM is stripped, the galaxy is almost completely (more than 90%) stripped when
an ICM density of 10^-27 g/cm^3 is applied. But again, a bulge prevents the
stripping of the ISM and reduces the amount being stripped by up to 10%.
Thereby, fewer stars are formed in the wake if the galaxy contains a bulge. The
dependence of the SFR on the disc tilt angle is not very pronounced. Hereby a
slight trend of decreasing star formation with increasing inclination angle can
be determined. Furthermore, with increasing disc tilt angles, less gas is
stripped and therefore fewer stars are formed in the wake. Reducing the disc
gas mass fraction results in a lower SFR when the galaxies evolve in vacuum. On
the other hand, the enhancement of the SFR in case of acting ram pressure is
less pronounced with increasing gas mass fraction. Moreover, the fractional
amount of stripped gas does not depend on the gas mass fraction.Comment: 11 pages, 18 figure
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