500 Naturwissenschaften
Refine
Year of publication
Document Type
- Conference Proceeding (31)
- Article (24)
- Part of a Book (3)
- Bachelor Thesis (1)
- Working Paper (1)
Language
- English (60) (remove)
Keywords
- Carbon sequestration (2)
- Ecological restoration (2)
- Gazebo (2)
- LiDAR (2)
- Robot operating system (ROS) (2)
- Simulation and Modeling (2)
- agriculture (2)
- lab on a chip (2)
- soil nutrients analysis (2)
- soil sampling (2)
Institute
- Fakultät AuL (52)
- Fakultät IuI (6)
- Fakultät WiSo (3)
This paper describes the development and test of a novel LiDAR based combine harvester steering system using a harvest scenario and sensor point cloud simulation together with an established simulation toolchain for embedded software development. For a realistic sensor behavior simulation, considering the harvesting environment and the sensor mounting position, a phenomenological approach was chosen to build a multilayer LiDAR model at system level in Gazebo and ROS. A software-in-the-loop simulation of the mechatronic steering system was assembled by interfacing the commercial AppBase framework for point cloud processing and feature detection algorithms together with a machine model and control functions implemented in MATLAB/ Simulink. A test of ECUs in a hardware-in-the-loop simulation and as well as HMI elements in a driver-in-the-loop simulation was achieved by using CAN hardware interfaces and a CANoe based restbus simulation.
Dairy farming has been the subject of public debate on animal welfare for a number of years now. Animal welfare discussions on dairy farming often include the demand for more nature connectedness in this area. This study focuses on the divergent perspectives of consumers and scientists on the importance of more nature connectedness for animal welfare strategies in German dairy farming. Within Europe, Germany is the main producer of cow’s milk and an important industry in many rural areas in Germany is dairy farming. The insights presented are based on qualitative interviews with dairy farming and livestock researchers from Germany and Austria. A key finding of this study is that we need to look more closely at the actual content of nature claims in animal welfare debates. The scientists interviewed tend to see idealized conditions in animal welfare discussions with images of nature which in fact seldom lead to improved conditions in dairy farming and, even then, only to a limited extent. The scientists interviewed rate calls for more nature connectedness in dairy farming from the nonagricultural public as anti-modern, complexity-reducing, and normative. Nevertheless, some of the scientists interviewed did have valuable insights into the nonagricultural public’s criticism of dairy farming practices. These scientists argued, however, that animal welfare needs to differentiate between nature connectedness and the innate needs of cattle when it comes to animal welfare strategies. An important conclusion of the study is that more discussion formats are needed to promote the exchange of ideas between different social groups attempting to understand animal welfare in dairy farming.
Hyperhydricity (HH) is one of the most important physiological disorders that negatively affects various plant tissue culture techniques. The objective of this study was to characterize optical features to allow an automated detection of HH. For this purpose, HH was induced in two plant species, apple and Arabidopsis thaliana, and the severity was quantified based on visual scoring and determination of apoplastic liquid volume. The comparison between the HH score and the apoplastic liquid volume revealed a significant correlation, but different response dynamics. Corresponding leaf reflectance spectra were collected and different approaches of spectral analyses were evaluated for their ability to identify HH-specific wavelengths. Statistical analysis of raw spectra showed significantly lower reflection of hyperhydric leaves in the VIS, NIR and SWIR region. Application of the continuum removal hull method to raw spectra identified HH-specific absorption features over time and major absorption peaks at 980 nm, 1150 nm, 1400 nm, 1520 nm, 1780 nm and 1930 nm for the various conducted experiments. Machine learning (ML) model spot checking specified the support vector machine to be most suited for classification of hyperhydric explants, with a test accuracy of 85% outperforming traditional classification via vegetation index with 63% test accuracy and the other ML models tested. Investigations on the predictor importance revealed 1950 nm, 1445 nm in SWIR region and 415 nm in the VIS region to be most important for classification. The validity of the developed spectral classifier was tested on an available hyperspectral image acquisition in the SWIR-region.
Methods: Systematic review of randomized controlled trials (RCT). Searches were conducted in five electronic databases. Studies were selected if they included patients with NP over 18 years old treated with aerobic exercise (AE) (e.g., cycling, running, hiking, and walking). The main outcome of interest was pain intensity. Qualitative and quantitative data were extracted. The risk of bias (RoB) was determined using the Cochrane RoB Tool-2 and the overall certainty of the evidence with the GRADE recommendations.
Results: Out of 21,585 initial records screened, a total of six individual studies published in ten manuscripts were included. There was a great heterogeneity between protocols, comparisons, and studies’ results (different magnitudes and directions). When looking at the effect of aerobic exercise versus control groups or other interventions on pain intensity measured with the VAS, not statistically (nor clinical) significant differences between aerobic exercise and control groups (MD [95%CI] 5.16 mm [-6.38, 16.70]) were identified. The combined effect of AE plus other interventions seems to be effective. Strength exercise obtained better effects than aerobic exercises (MD [95%CI]: -11.34 mm [-21.6, -1.09]).
Conclusions: Aerobic exercise presented positive results to reduce pain intensity, and improving disability, and physical and emotional functioning. However, the evidence is restricted, low quality, and heterogeneous.
Green roofs are known to mitigate the negative effects of urban consolidation by offering diverse ecosystem functions compared to non-vegetated roofs. However, the support for native biodiversity might be improved by using native plant species. In a mesocosm experiment, we studied the suitability of three commercial green-roof growth substrates for the establishment of 27 native plant species from dry sandy grasslands of northwestern Germany over the course of four years. The substrates were mineral-based, but differed in the layering of organic matter. Total establishment rates reached 44–59% in Year 4, indicating the general suitability of the substrates. During the first weeks after seeding, with light irrigation, the vascular plant cover was greater in the similar substrates Zincolit® Plus (Z) and Zincolit® Plus-Leicht (ZL) with their compost-based organic mulch layers than in the substrate Sedumteppich (ST) with its organic matter evenly admixed with the mineral aggregates. In Years 2 and 3, however, the vascular plant cover was greater in the ST substrate, likely due to the better availability of water and nutrients from the organic matter compared to the dry surface-mulch layer variants Z and ZL. After severe drought events, the decline in plant cover was more pronounced in the ST substrate, likely representing a trade-off between lush growth and a susceptibility to drought. An indicator-species analysis revealed differences in species composition between the ST and Z/ZL substrates. Annual plant species were indicators of the ST substrate. Perennials, such as Thymus pulegioides and Achillea millefolium, were typical of the Z and ZL substrates. In addition to the general suitability of the tested standard substrates for target species establishment, the study indicated that a combination of different layers of substrate components resulted in different vegetation patterns that may have a positive effect on green-roof biodiversity.
In urban areas, open space including brownfields often became rare due to increasing urbanisation. Urban brownfields can be important for biodiversity, but especially brownfields in early successional stages seem to be refused by urban residents due to their sparse vegetation and less aesthetic appearance. The aim of this study was to revegetate a young demolition site in the city core of Osnabrück, Germany and thereby to support native plant diversity and aesthetic values. We developed two seed mixtures of native plant species and tested them in a large-scale field experiment over two growing seasons.
Both seed mixtures developed towards structurally diverse and flower-rich vegetation. Establishment rates of sown species were consistently larger than 75%. Revegetation of the predominantly bare anthropogenically transformed soil by introduced species occurred fast. Vascular plant cover and vegetation height were higher on sown plots than in controls, but did not differ between the seed mixtures. Seeding did not increase plant species richness and did not reduce the establishment of a potentially invasive non-native plant species. The cover of Red-List species from the spontaneous vegetation was significantly higher in control plots. Our results indicate that not all aims can be reached on one restoration site. It has to be discussed if it is better to invest a restoration budget for measures aiming to increase acceptance of endangered pioneer plant species from the spontaneous vegetation or to introduce more attractive and more competitive species of later successional stages.
Technological support options for the usage of Brazilian Açaí berries in the European Food Market
(2022)
The highly perishable fruit açaí grows on palm trees in northern Brazil and is colloquially known as a berry with high nutritional value. The seed of the drupe makes up around 85 percent of the fruits weight and only the pulp around the seed is used for human consumption. The manufacturing step after harvest includes the pulping and the preservation of the fruit. The preservation step is necessary, because the açaí pulp contains a high microbial load. There are several preservation processes including the use of chlorinated or ozonated water, alcoholic fermentation, pasteurization, freezing or dehydration. Those techniques are overall not very gentle and have the potential to leave residues in the final product, which can change its typical sensorial characteristics. Therefore, an experiment was conducted, to see if a relatively new gentle preservation method called PEF can reduce the microbial load in an açaí- smoothie.
For this purpose, a PEF-machine was built and verified based on the paper from HEINZ ET AL. [2003]. The self-built machine works efficiently, when there is a reduction of microorganisms like Escherichia coli in apple juice due to the induced Pulsed Electric Fields. If this is the case, the described experiment with açaí-smoothie can be carried out with the self-built PEF- machine. In this experiment the results of the validation of this PEF-machine were not comparable to those from the paper from HEINZ ET AL. [2003]. So, the self-built PEF-machine in Brazil did not work sufficiently. Hence, the experiment which should show that a reduction of microorganisms, such as Escherichia coli, in açaí-smoothie with PEF is possible, was performed in Germany. It was accrued out at ELEA with using the PEFPilotTM Dual. This experiment confirmed the assumption, that microorganisms can be reduced in açaí-smoothie with PEF. Escherichia coli was reduced by 2 logs, Saccharomyces cerevisiae by 3 logs and Lactobacillus plantarum by 6 logs. And a comparison between PEF and the known preservation methods for açaí showed that it can be a compatible alternative.
Moreover, the topic, how açaí fits into the European Food Market is answered within this paper. When offering açaí food products to the European population, ideas can be originated from the well-working Brazilian market. It can be helpful to mix açaí with known European fruits for a better acceptance by the people. Then açaí can help to meet the Europeans needs of the current time for fresh and healthy food, especially when preserved with PEF. Furthermore, it is important to work towards a sustainable supply chain system from the cultivation until the unloading at the destination in Europe. Sustainability is important for the integration in the European market, not only for environmental protection, but also in terms of social stability and marketing purposes. In addition, access requirements, further food-related regulations, and the seasonality of açaí present a major hurdle.
Building on this thesis, further papers shall be written, not only in the field of the preservation of the açaí pulp with PEF, but also in the direction of combined preservation methods for açaí, the sustainable usage of the açaí seeds, product innovations containing the Brazilian fruit or various market research.
Stainless steel made to rust: a robust water-splitting catalyst with benchmark characteristics
(2015)
The oxygen evolution reaction (OER) is known as the efficiency-limiting step for the electrochemical cleavage of water mainly due to the large overpotentials commonly used materials on the anode side cause. Since Ni–Fe oxides reduce overpotentials occurring in the OER dramatically they are regarded as anode materials of choice for the electrocatalytically driven water-splitting reaction. We herewith show that a straightforward surface modification carried out with AISI 304, a general purpose austenitic stainless steel, very likely, based upon a dissolution mechanism, to result in the formation of an ultra-thin layer consisting of Ni, Fe oxide with a purity >99%. The Ni enriched thin layer firmly attached to the steel substrate is responsible for the unusual highly efficient anodic conversion of water into oxygen as demonstrated by the low overpotential of 212 mV at 12 mA cm−2 current density in 1 M KOH, 269.2 mV at 10 mA cm−2 current density in 0.1 M KOH respectively. The Ni, Fe-oxide layer formed on the steel creates a stable outer sphere, and the surface oxidized steel samples proved to be inert against longer operating times (>150 ks) in alkaline medium. In addition Faradaic efficiency measurements performed through chronopotentiometry revealed a charge to oxygen conversion close to 100%, thus underpinning the conclusion that no “inner oxidation” based on further oxidation of the metal matrix below the oxide layer occurs. These key figures achieved with an almost unrivalled-inexpensive and unrivalled-accessible material, are among the best ever presented activity characteristics for the anodic water-splitting reaction at pH 13.