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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.
Recording of Low-Oxygen Stress Response Using Chlorophyll Fluorescence Kinetics in Apple Fruit
(2023)
Long-term storage of apples (Malus x domestica, Borkh.) is increasingly taking place under Dynamic Controlled Atmosphere (DCA). The oxygen level is lowered to ≤ 1 kPa O2 and the apples are stored just above the Lower Oxygen Limit (LOL). Low oxygen stress during controlled atmosphere storage can lead to fermentation in apples if oxygen levels are too low. Chlorophyll fluorescence can be used to detect low-oxygen stress at an early stage during storage. The currently available non-imaging fluorescence systems often use the minimal fluorescence (Fo) parameter. In contrast, the use of chlorophyll fluorescence kinetics is insufficiently described. Therefore, this study aimed to gain more knowledge about the response of chlorophyll fluorescence kinetics to low oxygen stress in apples using a fluorescence imaging system. The results show that the kinetic fluorescence curves differ under aerobic and fermentation conditions. The fermentative conditions initiated a decrease in fluorescence intensity upon application of the saturation pulses during exposure to actinic light. This result was made at 18 °C and 2 °C ambient temperatures. Interestingly, the kinetic curve changed at 2 °C before fermentation products accumulated in the apples. Non-photochemical quenching (NPQ) decreased under fermentation conditions in the dark phase after relaxation. Upon entering the dark relaxation phase after Kautsky induction, ɸPSII began to increase. Under atmospheric oxygen conditions, ɸPSII reached values of 0.81 to 0.76, while under fermentation, ɸPSII values ranged from 0.57 to 0.44.
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.
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.
Klimabäume scheinen in der Mitte der Gesellschaft angekommen zu sein. Zahlreiche Empfehlungen finden sich in Onlinemedien und stellen die fünf oder zehn besten Baumarten vor. Dabei gibt es Schnittmengen. Interessanterweise enthält das Sortiment weitgehend bekannte und auch heute schon verwendete Arten. Es steht eine breite Palette an zukunftsfähigen Klimabäumen zur Verfügung, die teilweise noch gar nicht beachtet werden. In zwei Teilen sollen bekannte und weniger bekannte Klimabäume bezüglich ihrer Verwendbarkeit im urbanen Raum, ihrer Herkunft und ihres Ausbreitungspotenzials diskutiert werden.
Semi-natural grasslands (SNGs) are an essential part of European cultural landscapes. They are an important habitat for many animal and plant species and offer a variety of ecological functions. Diverse plant communities have evolved over time depending on environmental and management factors in grasslands. These different plant communities offer multiple ecosystem services and also have an effect on the forage value of fodder for domestic livestock. However, with increasing intensification in agriculture and the loss of SNGs, the biodiversity of grasslands continues to decline. In this paper, we present a method to spatially classify plant communities in grasslands in order to identify and map plant communities and weed species that occur in a semi-natural meadow. For this, high-resolution multispectral remote sensing data were captured by an unmanned aerial vehicle (UAV) in regular intervals and classified by a convolutional neural network (CNN). As the study area, a heterogeneous semi-natural hay meadow with first- and second-growth vegetation was chosen. Botanical relevés of fixed plots were used as ground truth and independent test data. Accuracies up to 88% on these independent test data were achieved, showing the great potential of the usage of CNNs for plant community mapping in high-resolution UAV data for ecological and agricultural applications.
Dynamic Controlled Atmosphere-Chlorophyll Fluorescence storage (DCA-CF) uses a fluorescence-based measurement method to detect fermentation in apples (Malus × domestica BORKH.) caused by low-oxygen levels at an early stage. In recent years, it has been observed that individual apples of the same variety and origin can exhibit different fermentation behavior when stored under completely identical conditions. The causes of the different fermentation behavior must be found in order to be able to use DCA storage optimally. This study aimed to find the causes of the different fermentation behaviors of individual apples. Our results show that fruit ripeness can affect the lower oxygen limit (LOL), especially immediately after harvest, when the starch degradation in the fruit is not yet complete. A significant increase in the LOL was observed in ‘Elstar’ (2020: 0.3 kPa, 0.6 kPa, 0.9 kPa; 2021: 0.3 kPa, 0.4 kPa, 0.6 kPa). ‘Braeburn’ also exhibited this behavior regarding the LOL at a lower level. The LOL could not be identified for some of the fruit (varying from 12.5% to 41.7% of the examined apples) previously stored in Ultra Low Oxygen (ULO) storage for 4 months. Also, the chlorophyll content in the apple skin influences the fluorescence measurement method. Within 2 weeks, the chlorophyll content in the apple skin was halved. If the chlorophyll content drops, the reliability of the fluorescence measurement also decreases. It turned out that apples with an Fv/Fm < 0.7 were unsuitable for valid LOL identification.
Weide für Trockensteher?
(2023)
Fütterung auf dem Prüfstand
(2023)
The influence of moderate electric fields (MEF) on thermally induced gelation and network structures of patatin enriched potato protein (PPI) was investigated. PPI solutions with 9 wt% protein (pH 7) and 25 mM NaCl were heated from 25 to 65 °C via OH (3–24 V/cm) or conventional heating (COV) at various come-up (240 s and 1200 s) and holding times (30 s and 600 s). Self-standing gels were produced but less proteins denatured when heated via OH. Further, SDS-PAGE and GPC measurements revealed more native patatin remaining after OH treatment. Scanning electron microscopy showed OH gels to have more gap-like structures and frayed areas than COV treated gels which resulted in lower water holding capacity. On molecular scale, less hydrophobic interactions were measured within the protein network and FTIR trials showed the MEF to affect beta-sheet structures. OH gels further showed lower rigidity and higher flexibility, thus, gelling functionality was affected via OH.
The present study aims to compare the effects of maternal and offspring treatment with 25-hydroxycholecalciferol (25-OHD3) and vitamin D3 on vitamin D status, mineral homoeostasis, bone metabolism and locomotion in the offspring. Either vitamin D3 (50 μg/kg diet) or 25-OHD3 (50 μg/kg diet) was supplemented to the gestation and lactation diets of 49 multiparous sows and/or to the diets of their growing offspring. Treatment of the sows did not affect plasma concentrations of 25-OHD3 of the offspring. Pigs fed 25-OHD3 had higher plasma concentrations of 25-OHD3 than pigs that received vitamin D3 during rearing and fattening. However, neither plasma concentrations of calcium, phosphate and bone markers during the observation period nor bone ash and bone mineral density at slaughter were clearly affected by the treatment. Maternal and offspring treatment with 25-OHD3 instead of vitamin D3 resulted in a slight reduction in the prevalence of leg swelling. In addition, more pigs walked with even steps and normal stride length. Further studies are needed to test whether the slight effects observed in the present experiment are reproducible and of relevance for animal health and welfare. In that case, the underlying mechanisms should be revealed in order to take advantage of potentially beneficial influences especially under certain feeding regimes.
Novel foods by process are a special case in the catalogue of the ten novel food categories according to Article 3 (2) point (a) of the Novel Food Regulation (EU) 2015/2283, since the other nine categories derive their assessment as possible novel foods from their purely substantial properties. In the case of novel foods by process, the problem of dealing with the reference date of 15 May 1997, which is in the end a random reference date, is particularly significant. It would make more sense to have a dynamic reference date that ‘moves along the timeline’ or at least is reset from time to time and is more up-to-date. The characteristic that a process causes ‘significant changes in the composition or structure of the food, affecting its nutritional value, metabolism or level of undesirable substances’ must be understood in such a way that it is only a question of the generation of undesirable substances through the application of the process, but not their reduction, e.g. the reduction of undesirable microorganisms. Finally, the question also arises as to how the assessment of the process technology relates to the assessment of a food in the context of a novel food by composition category. This concerns the exemption for foods that have a history of use as safe foods, which, according to the view taken here, must also be interpreted into the category of novel foods by process.
Leftovers lovers vs. haters: A latent class analysis on dinner leftover management behaviours
(2023)
Die Studie untersucht die Heterogenität im Umgang mit Speiseresten in Haushalten, insbesondere unter Verwendung von Mahlzeitensets mit angepassten Portions- und Zutatengrößen. Durch eine latenten Klassenanalyse werden Verbrauchersegmente identifiziert, wobei die positive Einstellung zu Essensresten und bewusster Umgang damit untersucht werden. Die Studie analysiert auch die Auswirkungen von Emotionen, persönlichen Normen, Intentionen und Essensbeschaffungsroutinen auf die Zugehörigkeit zu einem Resteverwertungssegment. Daten von 868 Haushalten aus sechs Ländern zeigen fünf Verbrauchersegmente mit Unterschieden in der Menge der Essensreste. Mahlzeitensets haben heterogene Auswirkungen, indem sie in einigen Segmenten die Menge der Essensreste verringern, in anderen jedoch nicht. Die Ergebnisse bieten neue Erkenntnisse über die Vielfalt im Umgang mit Speiseresten und liefern Implikationen für Theorie und Politik zur Reduzierung von Lebensmittelverschwendung im Haushalt.
Lahmheiten bilden bei Sauen und wachsenden Schweinen ein ernstzunehmendes Gesundheits- und Tierwohlproblem. Die Studie zeigte, dass der diätetische Einsatz von 25-Hydroxycholecalciferol im Austausch zum Vitamin D3 zu einer Reduktion von Bewegungsproblemen bei Sauen und wachsenden Schweinen geführt hat.
Vitamin D für starke Beine
(2023)
Farmland bird populations are in a deep crisis across Europe. Agri-environment schemes (AES) were implemented by the European Union to stop and reverse the general decline of biodiversity in agricultural landscapes. In Germany, flower strips are one of the most common AES. Establishing high-quality perennial wildflower strips (WFS) with species-rich native forb mixtures from regional seed propagation is a recent approach, for which the effectiveness for birds has not yet been sufficiently studied. We surveyed breeding birds and vegetation on 40 arable fields with WFS (20 with single and 20 with aggregated WFS) and 20 arable fields lacking WFS as controls across Saxony-Anhalt (Germany). Additionally, vegetation composition, WFS quantity and landscape structure (e.g. distance to nearest woody element) were considered in our analyses. All WFS were established with species-rich native seed mixtures (30 forbs) in agricultural practice as AES. Arable fields with WFS had a higher species richness and territory density of birds than controls, confirming the effectiveness of this AES. A forb-rich vegetation was the main driver promoting birds. Flower strip quantity at the landscape level had positive effects only on bird densities, but also single WFS achieved benefits. A short distance from WFS to woody elements increased total bird species richness. However, the density of farmland birds, which are target species of these AES, were negatively affected by the proximity and proportion of woody elements in the vicinity. The effect of the proportion of non-intensively used open habitats and overall habitat richness was unexpectedly low in the otherwise intensively farmed landscape. Species-rich perennial WFS significantly promoted breeding birds. Successful establishment of WFS, resulting in high-quality habitats, a high flower strip quantity as well as implementation in open landscapes were shown to maximise the effectiveness for restoring declining and AES target farmland birds.
In open-field vegetable production, high quantities of soil mineral nitrogen (Nmin) and N-rich crop residues often remain in the field at harvest. After the harvest of crops in autumn, this N can lead to considerable nitrate (NO3−) losses during the subsequent winter leaching period. In four field trials, different tillage depths (3–4, 10, 30 cm) and dates (early autumn, late autumn, early spring) were investigated to reduce N losses after growing spinach in the autumn. In a further treatment, the nitrification inhibitor 3,4-Dimethylpyrazole phosphate (DMPP) was directly applied to the crop residues. Potential N losses were calculated by a balance sheet approach based on Nmin concentration (0–90 cm), measured N mineralization and N uptake by catch crops. By postponing the tillage date from early to late autumn or spring, resprouting spinach stubbles acted as a catch crop, reducing N losses by up to 61 kg ha−1. However, if the spinach biomass collapsed, the N losses increased by up to 33 kg ha−1 even without tillage. The application of DMPP as well as the tillage depth were less effective. Overall, postponing tillage to spring seems to be the most promising approach for reducing N losses during the off-season.
Wieviel Wasser säuft die Sau
(2022)
A project was initiated to apply dietary CP reduction under commercial conditions. The main objective was to demonstrate and validate that dietary CP can be reduced without compromising broiler performance in a production system which is already rather efficient. In addition, we wanted to demonstrate the potential of dietary CP reduction on reducing N-excretions especially in the context of German revised regulations and monitoring attempts. Finally, as previous research suggested, few further aspects such as impact of dietary CP reduction on litter quality and quantity, footpad health, change of ingredient inclusion levels and related impact on sustainability impact factors were evaluated.
Shredlage für Masttiere?
(2022)
Mehr Tränken bei Hitze
(2022)
Braune Brühe, was tun?
(2022)
Kotwasser beim Pferd
(2022)
The impact of pulsed light (PL) treatment on naturally occurring microorganisms, mycotoxins, and on physicochemical properties in red pepper powder was investigated. Powder samples were exposed to different PL treatments up to 61 pulses, with fluence ranging from 1.0 to 9.1 J/cm2. The highest fluence applied (9.1 J/cm2, 61 pulses, 20 s) resulted in 2.7, 3.1, and 4.1 log CFU/g reduction of yeasts, molds, and total plate counts (TPC), where initial microbial loads were 4.6, 5.5, and 6.5 log CFU/g, respectively. At the same fluence intensity, a maximum reduction of 67.2, 50.9, and 36.9% of aflatoxin B1 (AFB1), total aflatoxins (AF), and ochratoxin A (OTA) were detected, respectively. Proportional increase in temperature of the samples was observed from the absorbed PL energy, reaching maximum of 59.8°C. The inactivation of investigated microorganisms and mycotoxins followed first-order kinetics (R2 > 0.95). The fluence intensity at 6.9 and 9.1 J/cm2 did not cause degradation, but rather a significant (p < .05) and apparent increase of total phenols. Total color difference (ΔE*) revealed only “slight differences,” compared to the untreated sample. In conclusion, higher reduction of microbial load and mycotoxins in red pepper powder could be achieved, when higher treatment intensity was applied. This suggests the PL as a potential technology for decontamination of red pepper powder and other spice powders.
Der Schwerpunkt des vorliegenden Papiers liegt auf der Nachfrageseite. In realen Labors verwenden wir einen standardisierten empirischen Ansatz, um verschiedene Nudging-Maßnahmen aus dem Bereich der physischen Umwelt und des Entscheidungsprozesses der Verbraucher zu vergleichen. Wir vergleichen die Auswirkungen ein und derselben Maßnahme in verschiedenen Umgebungen und die Auswirkungen verschiedener, aufeinander folgender Nudging-Maßnahmen in derselben Umgebung. Die Daten wurden in acht Betriebs- und Schulkantinen in Deutschland in zwei Projektdurchläufen (2016/2017; 2019/2020) erhoben. Es wurde ein ähnliches Interventionskonzept angewandt. Die Vergleichbarkeit wurde durch eine harmonisierte Speisekarte gewährleistet. Die erste Iteration des Projekts ergab, dass nur ein Nudge (oberste Menüposition, +22,5 %) zu einem signifikanten Anstieg der Wahl nachhaltiger Lebensmittel führte, während die Ergebnisse der zweiten Iteration zeigten, dass alle Nudge-Interventionen (beste Thekenposition, +11,6 %; oberste Menüposition, +6,9 %; Etikett plus Informationen, +15,9 %) die Wahl der Verbraucher positiv beeinflussten. Mögliche Erklärungen wie die striktere Einhaltung des Versuchsplans in den Cafeterien, aber auch gesellschaftliche Entwicklungen wie das Aufkommen der Fridays for Future-Bewegung werden diskutiert. Da die Ergebnisse je nach Standort und Umfeld variieren, legen unsere Ergebnisse nahe, dass Nudges situativen Bedingungen angepasst werden müssen, um die höchste Wirksamkeit zu erzielen.
The present study investigates properties of heat-induced, self-standing gels of globular proteins. Native egg white protein (EWP) with 9,8 wt% protein and 0,395 wt% NaCl content was adjusted to pH = 7,0 and heated from 25 to 85 °C via Ohmic heating (OH) and conventional heating (COV) with respective come-up times (CUT, 240 and 1200 s) and holding times (HOLD, 30 and 900 s). Gels heated under OH showed lower denaturation levels and less water holding capacity. When HOLD was short, the firmness of OH gels exceeded COV gel firmness but deceeded at long HOLD. Similarly, at short HOLD OH samples presented higher hydrophobic interactions whereas at long HOLD COV gels showed more hydrophobic interactions. This correlated with changes of intermolecular beta-sheet structures which increased with HOLD at COV but decreased or remained unchanged during OH. Furthermore, as an SDS-PAGE revealed the main EWP, ovalbumin, did not fully denature when heated via OH, this lead to the assumption that the oscillatory electric field partially interferes the complete denaturation and development of intermolecular beta-sheet structures and hydrophobic interactions during thermal gelation of this protein. Scanning electron microscopy also showed deviances in network structures between OH and COV as COV gels exhibited a denser and OH gels a more open and porous network structure.
Currently, the modelling of drying processes of plant tissues pre-treated by pulsed electric field (PEF) is following experimentally identified curves or separate heat and mass transfer and diffusion models with different levels of accuracy. This research had two major objectives: mathematical modeling and control of drying process of different vegetables pretreated by PEF during convective drying. The mathematical modeling was based on Luikov's heat and mass transfer model along with properties of different vegetables. Computer modelling was done using the difference method for predicting moisture and the temperature potentials of untreated and PEF-treated vegetables. The formulation and the solution procedures were applied to simulate the simultaneous heat and mass transfer in selected vegetables subjected to the convective drying. Suggested model had a good correlation with experimental results. Moreover, cell disintegration index can be used as a controllable parameter in heat and mass transfer models to predict drying behavior of potato, onion, and carrot tissues. Obtained drying models can be used as a mathematical tool to predict drying behavior for various types of agricultural products pre-treated by pulsed electric field.
The impact of Pulsed Electric Fields (PEF) on the peeling ability of different fruits and vegetables in particular tomatoes, peaches, peppers, and oranges were investigated. Samples were exposed to a fixed electric field strength of 2.15 kV/cm. The specific energy ranged from 0.6 kJ/kg to 50.3 kJ/kg. The treated raw materials were analysed regarding to the peeling ability, skin size and weight and firmness. The best result for tomatoes at a specific energy of 1.2 kJ/kg induced a high score of peeling ability that led to less product loss and could therefore increase the yield by 33.84%–41.53% compared to untreated samples. Moreover, an increased skin size by a factor of 3.7 was observed. However, PEF had no significant impact on peeling ability of oranges, peppers, and peaches. Although oranges showed an improvement in peeling ability by up to 32%, this cannot be traced back to the PEF treatment. The different properties and structures of the raw materials were discussed and provided indications about the limitation of PEF.