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The development of base metal electrodes that can act as active and stable oxygen generating electrodes in water electrolysis systems, especially at low pH levels, remains a challenge. The use of suspensions as electrolytes for water splitting has until recently been limited to photoelectrocatalytic approaches. A high current density (j=30 mA/cm2) for water electrolysis has been achieved at a very low oxygen evolution reaction (OER) potential (E=1.36 V vs. RHE) using a SnO2/H2SO4 suspension-based electrolyte in combination with a steel anode. More importantly, the high charge-to-oxygen conversion rate (Faraday efficiency of 88% for OER at j=10 mA/cm2 current density). Since cyclic voltammetry (CV) experiments show that oxygen evolution starts at a low, but not exceptionally low, potential, the reason for the low potential in chronoamperometry (CP) tests is an increase in the active electrode area, which has been confirmed by various experiments. For the first time, the addition of a relatively small amount of solids to a clear electrolyte has been shown to significantly reduce the overpotential of the OER in water electrolysis down to the 100 mV region, resulting in a remarkable reduction in anode wear while maintaining a high current density.
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.
The objective of this article is to prepare for the initial certification according to IFS Global Markets Food V3 at the Landshuter Brauhaus AG private brewery at the Ellermühle site, which is expected in August 2025, and to create the basis for a potential follow-up certification according to IFS Food. The IFS Global Markets Food Program V3 is a standardized, voluntary and non-accredited assessment program for food companies, both for retail and manufacturer brand products (IFS 2023, p. 10 f.). It is based on the specifications of the Global Markets Program developed in 2008 (GFSI 2023a; VDOE 2020, p. 620).
The methodology of the target/actual analysis was used to work on the topic in order to be able to carry out a conformity check with regard to the requirements of IFS Global Markets Food V3 (see Appendix 3; IFS 2023). Observations, document analyses and employee surveys were carried out to obtain the most meaningful information possible. These have been recorded and evaluated within the target-performance analysis. A total of 65 deviations (equivalent to 53.7%) were identified at the basic level, and 60 deviations (equivalent to 82.2%) at the intermediate level. These were either processed as directly implemented corrective actions or formulated as recommendations for continuous improvement in the form of an action plan (see Appendix 15). The presentation of the action plan shows the deviations, the resulting measures, the associated responsibilities, the time period with the starting point and end point of the measures, and the current status. In addition a subdivision into "Basic" and "+Intermediate" was made for a better overview in the subsequent processing by the brewery.
A review as well as assessment of relevant requirements with regard to processes and significant violations after completion of the new building and commissioning at the Ellermühle site with regard to correlation with a potential "major" rating is recommended on the part of the operations manager or brewmaster (IFS 2023, p. 30).
To assess the effect of intercropping on malting quality a field trial with spring barley (Hordeum vulgare) and legume (pea) as well as non-legume (camelina and linseed) intercrops in two additive seeding ratios as well as sole cops was established in 2017 at the organic experimental station of University of Applied Sciences Osnabrück in North-Western Germany. Two tested malting barley cultivars (cv. Marthe and cv. Odilia) showed different performance, but all variants achieved brewing quality. Results after two years indicate that linseed and camelina were able to limit protein content. For best land-use efficiency of malting barley production intercropping with linseed showed best results. Mixed intercropping can help to promote internal efficiency loops and is therefore a promising sustainable intensification strategy for more resilient future crop production under changing climate conditions.
Background
Spinach is a nitrogen (N) demanding crop with a weekly N uptake of up to 60 kg ha–1. Consequently, a high N supply is required, which can temporarily lead to high quantities of nitrate (NO3–) being at risk of leaching.
Aims
The objective of this study was to develop a N fertilization approach to reduce the risk of NO3– leaching in field-grown spinach production without adversely affecting crop yield and quality at an early and late harvest stage.
Methods
Ten fertilization trials were conducted to compare different base fertilization rates and splits of top dressings. For top dressings, granulated fertilizers or foliar sprays were used. In a further treatment, N supply was reduced by withholding the second top dressing of 50–70 kg ha−1.
Results
Nitrate concentration at risk of leaching was considerably reduced by decreasing the base fertilizer rate as well as by splitting the top dressing. However, at an early harvest stage, total aboveground dry mass was reduced by, on average, 6% by these measures across all seasons. In contrast, at a later harvest stage, spinach was less affected by the fertilizer schedule. Urea foliar sprays proved to be insufficient in promoting plant growth and caused leaf necrosis. A reduced N supply led to impaired plant growth and yellowish leaves in both spring and winter.
Conclusions
Base N fertilization of spinach is only required in spring, but not in other seasons. Despite slight yield reduction, the top dressing should be split to reduce the risk of NO3− leaching after an early harvest.
Background
The current development of sensor technologies towards ever more cost-effective and powerful systems is steadily increasing the application of low-cost sensors in different horticultural sectors. In plant in vitro culture, as a fundamental technique for plant breeding and plant propagation, the majority of evaluation methods to describe the performance of these cultures are based on destructive approaches, limiting data to unique endpoint measurements. Therefore, a non-destructive phenotyping system capable of automated, continuous and objective quantification of in vitro plant traits is desirable.
Results
An automated low-cost multi-sensor system acquiring phenotypic data of plant in vitro cultures was developed and evaluated. Unique hardware and software components were selected to construct a xyz-scanning system with an adequate accuracy for consistent data acquisition. Relevant plant growth predictors, such as projected area of explants and average canopy height were determined employing multi-sensory imaging and various developmental processes could be monitored and documented. The validation of the RGB image segmentation pipeline using a random forest classifier revealed very strong correlation with manual pixel annotation. Depth imaging by a laser distance sensor of plant in vitro cultures enabled the description of the dynamic behavior of the average canopy height, the maximum plant height, but also the culture media height and volume. Projected plant area in depth data by RANSAC (random sample consensus) segmentation approach well matched the projected plant area by RGB image processing pipeline. In addition, a successful proof of concept for in situ spectral fluorescence monitoring was achieved and challenges of thermal imaging were documented. Potential use cases for the digital quantification of key performance parameters in research and commercial application are discussed.
Conclusion
The technical realization of “Phenomenon” allows phenotyping of plant in vitro cultures under highly challenging conditions and enables multi-sensory monitoring through closed vessels, ensuring the aseptic status of the cultures. Automated sensor application in plant tissue culture promises great potential for a non-destructive growth analysis enhancing commercial propagation as well as enabling research with novel digital parameters recorded over time.
Animal husbandry methods also play an important role in public discussion, as animal welfare is often valued in society by visual perceptions. In this context, there is often an idealized idea of livestock husbandry and nutrition, which is staged by ideal-typical images. In the minds of many citizens, nature-loving images trigger a positive imagination that results from the longings of urban living conditions. Media and stakeholder analyses indicate that the use of straw in livestock husbandry and nutrition also has a positive impact on the welfare of livestock. According to this, straw is preferred by the public for more animal welfare. But what is not considered is the fact that the straw must be of impeccable hygienic quality
Animal husbandry methods also play an important role in public discussion, as animal welfare is often valued in society by visual perceptions. In this context, there is often an idealized idea of livestock husbandry and nutrition, which is staged by ideal-typical images. In the minds of many citizens, nature-loving images trigger a positive imagination that results from the longings of urban living conditions. Media and stakeholder analyses indicate that the use of straw in livestock husbandry and nutrition also has a positive impact on the welfare of livestock. According to this, straw is preferred by the public for more animal welfare.
But what is not considered is the fact that the straw must be of impeccable hygienic quality. Fungal infestation and the formation of mycotoxins in straw can cause diseases in livestock with consequences for animal welfare.
The first evaluation of a perfect straw quality also takes place in science through sensory tests, i.e. through smell, grip, colour and impurities. Only in the case of abnormalities in the sensory tests are further examinations indicated, such as microbiological examination procedures.
The hygienic properties of straw were examined on the basis of these assessment criteria. In addition to the microbiological-hygienic tests, the sensors of the straw were also tested.
The results show that there are no abnormalities in the sensory examination of the hygiene status. This was to observe an impeccable hygiene status.
However, the microbiological-hygienic investigations showed that the straw had microbiological as well as mycotoxin loads above the orientation values. This can have negative health effects, such as diseases for farm animals.
The scientific results led to the conclusion: The public discussion about animal welfare, which is often conducted primarily on the basis of visual impressions, could gain in scientific resilience if it includes objective results such as microbiological analyses in addition to images in order to evaluate animal welfare in livestock farming
In this paper, we evaluate the application of Bayesian Optimization (BO) to discrete event simulation (DES) models. In a first step, we create a simple model, for which we know the optimal set of parameter values in advance. We implement the model in SimPy, a framework for DES written in Python. We then interpret the simulation model as a black box function subject to optimization. We show that it is possible to find the optimal set of parameter values using the open source library GPyOpt. To enhance our evaluation, we create a second and more complex model. To better handle the complexity of the model, and to add a visual component, we build the second model in Simio, a commercial off-the-shelf simulation modeling tool. To apply BO to a model in Simio, we use the Simio API to write an extension for optimization plug-ins. This extension encapsulates the logic of the BO algorithm, which we deployed as a web service in the cloud.
The fact that simulation models are black box functions with regard to their behavior and the influence of their input parameters makes them an apparent candidate for Bayesian Optimization (BO). Simulation models are multivariable and stochastic, and their behavior is to a large extent unpredictable. In particular, we do not know for sure which input parameters to adjust to maximize (or minimize) the model’s outcome. In addition, the complex models can take a substantial amount of time to run.
Bayesian Optimization is a sequential and self-learning algorithm to optimize black box functions similar to as we find them in simulation models: they contain a set of parameters for which we want to identify the optimal set, they are expensive to evaluate, and they exhibit stochastic noise. BO has proven to efficiently optimize black box functions from varius disciplines. Among those, and most notably, it is successfully applied in machine learning algorithms to optimize hyperparameters.