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Water retention properties of wood fiber based growing media and their impact on irrigation strategy
(2024)
Distribution of water and air in growing media during ebb-and-flow irrigation depends on water storage properties (water retention curve) and water transport properties (hydraulic conductivity) of the materials. Growing media with their high number of coarse pores are known to exhibit strong hysteresis, i.e., differences in the water retention properties during drying and wetting cycles. To account for potential ecological disadvantages of peat, wood fibers are commonly used as substitutes for peat in growing media. However, the wood fibers generally have higher air capacities and hydraulic conductivities and lower water capacities compared to peat which may results in necessary adaptions of the irrigation strategy. Tools to optimize irrigation systems are physically based water transport models, such as HYDRUS-1D, which is commonly used to describe water transport in soils, but not often for growing media. In this study, white peat and pure wood fibers were used to describe differences in their water retention behavior. Water retention curves (drying cycles) and hydraulic conductivities were measured with standard analytical procedures. Hysteresis of the water retention curves was analytically determined based on their capillary rise properties. The results were used with a modified HYDRUS-1D model to test model quality against measured water contents during ebb-and-flow irrigation cycles and to optimize the irrigation strategy for the different materials. The results showed that the model quality was sufficiently good only if the strong hysteresis of the water retention curves was considered during the simulation process. Different strategies were tested to modify ebb-and-flow irrigation (irrigation frequency, irrigation duration and irrigation height) in that way that the water suction in the root zone was similar to that of the peat material. Simulation results showed that significant improvements could only be reached by increasing the flooding depth in ebb-and-flow systems to ensure an optimum water supply of plants in the wood fiber based growing media.
Wood fibers can contribute to replacing peat in growing media and thus help to protect peatlands. As domestic, renewable raw materials, they represent a sustainable option for this purpose. To date, however, wood fibers are usually used as a peat substitute at a maxi-mum of 30% (v/v). A main reason for this limitation is the insufficient microbial stability of wood fibers, which favors nitrogen immobilization and can thus impair nitrogen supply of plants. To address this drawback, in this study wood fibers were subjected to different thermal or thermal-hydrolytic treatments. Seedling tests with napa cabbage were conducted to determine whether treated wood fibers were free of phytotoxic substances. Mixtures with 50% (v/v) wood fiber and white peat each were used. In addition, three wood fiber varieties were evaluated in the cultivation of petunia. Two wood fiber proportions (30 and 60% v/v) and two nitrogen fertilization rates (common and increased supply) were included in each case. In the seedling trial with napa cabbage, no phytotoxic effects were detectable in any of the wood fiber variants investigated. However, when cultivating petunias, both shoot mass growth and number of flowers decreased with increasing wood fiber content. In substrates with a wood fiber content of 60% (v/v), plant development was inhibited so severely that the petunias no longer achieved marketable quality. Increased nitrogen fertilization was able to compensate for this negative effect only in few cases. This suggests that other factors than nitrogen limited plant growth in wood fiber-rich substrates. Among others, physical proper-ties such as the lower water capacity of wood fibers may be a cause. More in-depth investigations are still required in this regard.
Enhancing the nutritional value of pears through agronomic biofortification with iodine (Abstract)
(2024)
Response of petunia to wood fibre amended peat substrate under ebb-and-flow irrigation (Abstract)
(2024)
The development of non-precious metal-based electrodes that actively and stably support the oxygen evolution reaction (OER) in water electrolysis systems remains a challenge, especially at low pH levels. The recently published study has conclusively shown that the addition of haematite to H2 SO4 is a highly effective method of significantly reducing oxygen evolution overpotential and extending anode life. The far superior result is achieved by concentrating oxygen evolution centres on the oxide particles rather than on the electrode. However, unsatisfactory Faradaic efficiencies of the OER and hydrogen evolution reaction (HER) parts as well as the required high haematite load impede applicability and upscaling of this process. Here it is shown that the same performance is achieved with three times less metal oxide powder if NiO/H2 SO4 suspensions are used along with stainless steel anodes. The reason for the enormous improvement in OER performance by adding NiO to the electrolyte is the weakening of the intramolecular O─H bond in the water molecules, which is under the direct influence of the nickel oxide suspended in the electrolyte. The manipulation of bonds in water molecules to increase the tendency of the water to split is a ground-breaking development, as shown in this first example.
Die Umstände des globalen Klimawandels erfordern zukünftig auch in Hannover eine Neuauswahl der Stadtbaumarten zugunsten hitze- und trockenheitstoleranter Arten. In Zusammenarbeit mit der Stadt Hannover wurde ein Baumentwicklungskonzept für zukünftige Baumpflanzungen in der Landeshauptstadt erarbeitet. Im Konflikt zwischen Schutz der heimischen Flora und Fauna und Maßnahmen der Klimaanpassung wurde die „Assisted Migration“ als Ansatz und Kompromiss zwischen beiden Bereichen gewählt. Hierbei werden Arten durch gezielte Eingriffe parallel zum Verlauf der theoretischer Arealverschiebung der Klimaerwärmung bewegt. Um mögliche Herkunftsgebiete für diese Arten zu finden, wurden auf europäischer Ebene klimatische Analoggebiete für Hannovers zukünftiges Klima gesucht. Das Klima verschiedener Standorttypen Hannovers wurde mithilfe von aktuellen klimatischen Szenarios für den Zeitraum 2080-2100 projektiert und anschließend europaweit mit dem lokalen Klima der Periode 1970-2000 verglichen. Gebiete Süd- und Südosteuropas verfügen über klimatischen Eigenschaften, welche dem in Hannover zukünftig erwarteten Klima entsprechen. Sie wurden auf ihr Gehölzvorkommen untersucht. Unter Einbezug der natürlichen Standortbedingungen und bereits gemachter Erfahrungen wurde eine umfangreiche Artenliste erarbeitet. Diese schlägt Baumarten vor, die zukünftig an die Klimabedingungen angepasst sind und jetzt und im Verlauf der nächsten Jahrzehnte an verschiedenen Standorten Hannovers gepflanzt werden können.
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.
Introduction: Patients undergoing revision total hip surgery (RTHS) have a high prevalence of mild and moderate preoperative anemia, associated with adverse outcomes. The aim of this study was to investigate the association of perioperative allogeneic blood transfusions (ABT) and postoperative complications in preoperatively mild compared to moderate anemic patients undergoing RTHS who did not receive a diagnostic anemia workup and treatment before surgery. Methods: We included 1,765 patients between 2007 and 2019 at a university hospital. Patients were categorized according to their severity of anemia using the WHO criteria of mild, moderate, and severe anemia in the first Hb level of the case. Patients were grouped as having received no ABT, 1–2 units of ABT, or more than 2 units of ABT. Need for intraoperative ABT was assessed in accordance with institutional standards. Primary endpoint was the compound incidence of postoperative complications. Secondary outcomes included major/minor complications and length of hospital and ICU stay. Results: Of the 1,765 patients, 31.0% were anemic of any cause before surgery. Transfusion rates were 81% in anemic patients and 41.2% in nonanemic patients. The adjusted risks for compound postoperative complication were significantly higher in patients with moderate anemia (OR 4.88, 95% CI: 1.54–13.15, p = 0.003) but not for patients with mild anemia (OR 1.93, 95% CI: 0.85–3.94, p < 0.090). Perioperative ABT was associated with significantly higher risks for complications in nonanemic patients and showed an increased risk for complications in all anemic patients. In RTHS, perioperative ABT as a treatment for moderate preoperative anemia of any cause was associated with a negative compound effect on postoperative complications, compared to anemia or ABT alone. Discussion: ABT is associated with adverse outcomes of patients with moderate preoperative anemia before RTHS. For this reason, medical treatment of moderate preoperative anemia may be considered.
Background
Beta-blocker (BB) therapy plays a central role in the treatment of cardiovascular diseases. An increasing number of patients with cardiovascular diseases undergoe noncardiac surgery, where opioids are an integral part of the anesthesiological management. There is evidence to suggest that short-term intravenous BB therapy may influence perioperative opioid requirements due to an assumed cross-talk between G-protein coupled beta-adrenergic and opioid receptors. Whether chronic BB therapy could also have an influence on perioperative opioid requirements is unclear.
Methods
A post hoc analysis of prospectively collected data from a multicenter observational (BioCog) study was performed. Inclusion criteria consisted of elderly patients (≥ 65 years) undergoing elective noncardiac surgery as well as total intravenous general anesthesia without the use of regional anesthesia and duration of anesthesia ≥ 60 min. Two groups were defined: patients with and without BB in their regular preopreative medication. The administered opioids were converted to their respective morphine equivalent doses. Multiple regression analysis was performed using the morphine-index to identify independent predictors.
Results
A total of 747 patients were included in the BioCog study in the study center Berlin. 106 patients fulfilled the inclusion criteria. Of these, 37 were on chronic BB. The latter were preoperatively significantly more likely to have arterial hypertension (94.6%), chronic renal failure (27%) and hyperlipoproteinemia (51.4%) compared to patients without BB. Both groups did not differ in terms of cumulative perioperative morphine equivalent dose (230.9 (BB group) vs. 214.8 mg (Non-BB group)). Predictive factors for increased morphine-index were older age, male sex, longer duration of anesthesia and surgery of the trunk. In a model with logarithmised morphine index, only gender (female) and duration of anesthesia remained predictive factors.
Conclusions
Chronic BB therapy was not associated with a reduced perioperative opioid consumption.
Test von Schnellverfahren zur Bestimmung der Benetzungseigenschaften von Kultursubstraten (Abstract)
(2024)
Besides yield reduction weeds have positive effects, like enhancing biodiversity or reducing soil erosion. The aim of the work is to enhance biodiversity without yield losses. In growing season 2021/22 a field experiment with winter triticale was conducted to experience the impact of mechanical weed control, sowing date and sowing rate. Especially hoeing had a positive impact on vegetative growth and grain yield while weed growth was inhibited but weed biodiversity stayed equal or increased. A lower seed rate or an earlier sowing date made in general no difference at flowering or harvesting stage.
Inhalt dieser Arbeit ist die Entwicklung und Durchführung eines BIM-Workflows für die Erfassung, Aufbereitung und Weiterbearbeitung von Gelände-Bestandsdaten in der Landschaftsarchitektur. Der entwickelte Workflow basiert auf der Analyse vorliegender BIM-Richtlinien und Leitfäden aus dem Bereich der Infrastrukturplanung. Es wird herausgestellt, welche Anforderungen an Bestandsdaten in BIM gestellt werden. Diese können auf Grund überschneidender Inhalte auf die Fachdisziplin der Freiraumplanung übertragen werden. Der Workflow integriert auf der einen Seite 3D-Bestandsdaten der Vermessungsämter, auf der anderen Seite Vermesserdaten aus der Ingenieurvermessung. Die Daten werden für die Weiterverwendung in BIM-Softwares aufbereitet und an diese übergeben. Auf Grundlage eines Projektbeispiels wird in fünf verschiedenen BIM-Programmen die Erstellung eines Digitalen Geländemodells anhand derselben Punktedatei durchgeführt und dokumentiert. Die erstellten Geländemodelle werden in dasselbe Datenformat exportiert und hinsichtlich ihrer Übereinstimmung und Genauigkeit mittels ausgewählter Vergleichsmethoden geprüft. Abschließend werden einige Werkzeuge des Plug-ins ‚Environment‘ für die Modellierung und Weiterbearbeitung von Geländemodellen in Autodesk Revit getestet und bewertet. Die praktische Umsetzung des entwickelten Workflows wird detailliert im Anhang aufgezeigt.
Einleitung
Die Prävalenz der über 80-jährigen bei Ulcus cruris venosum (VLU) beträgt 4-5 %, obwohl diese Altersgruppe nur 1 % der Gesamtbevölkerung ausmacht. Zusätzlich wird bei VLU-Patienten häufig eine Mangelernährung beobachtet. Insbesondere geriatrische Patienten leiden darunter. Dabei ist bekannt, dass Mangelernährung Einfluss auf die Wundheilung und somit auf die Lebensqualität der Patienten hat. Diverse Studien beschreiben erste erfolgreiche ernährungstherapeutische Ansätze für einen beschleunigten Wundheilungsprozess. Allerdings ist die Ernährungstherapie bei VLU-Patienten wenig erforscht. Ziel dieser Arbeit ist es einen Überblick über den ernährungsphysiologischen Einfluss zur VLU zu schaffen, um mögliche Ernährungsinterventionen für geriatrische Patienten zu erhalten.
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.
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.
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.
Iron deficiency is a global issue and can lead to a variety of clinical pictures. The biofor-tification of vegetables with iron could complement the existing portfolio of iron-rich products, thus improving iron supply in the long term. In order to determine whether the iron-biofortified vegetables could meet this demand and would address appropriate target groups, a quantitative online survey was conducted in Germany. Based on 1000 consumer responses, a cluster analysis was performed. The results showed a four-cluster solution. The first cluster was holistically engaged, the second was fitness-affine but health unconcerned, the third cluster consists frugal eaters with a focus on medical prevention, and the fourth cluster are hedonists. No cluster focused its consumption on iron-enriched products, but instead all developed an individual mix of the three product groups.
Die vorliegende Abschlussarbeit befasst sich mit der Arbeitsweise des Building Information Modeling (BIM) in der Landschaftsarchitektur und der Untersuchung von Modellierungsop-tionen für Vegetationsobjekte. Wenngleich Vegetation einen wesentlichen Bestandteil der Planung von Außenanlagen darstellt, gibt es für den allgemeinen Umgang mit Bepflanzung in BIM bisher noch keine ausgereiften Konzepte. Insbesondere die Planung von Stauden-flächen wird in digitalen Modellen bisher kaum thematisiert. Es fehlen darüber hinaus allge-meine Workflows, um die Bepflanzungsplanung in den Prozess des Building Information Modeling zu integrieren. Das vorrangige Ziel dieser Arbeit ist daher die Entwicklung von exemplarischen Arbeitsab-läufen für das Aufgabenfeld der Bepflanzungsplanung innerhalb der 3D-Modellierungssoft-ware Autodesk Revit. Um die Potentiale des Programms bestmöglich zu nutzen, werden zudem die visuellen Programmierwerkzeuge des Softwaremoduls Dynamo verwendet. Die in Dynamo entwickelten benutzerdefinierten Tools ergänzen die Standardfunktionen von Revit und können für spezifische Modellierungsaufgaben wiederholt zum Einsatz kommen. Zum einen basiert die Modellierung in Revit auf den BIM-Grundlagen der Fertigstellungsgrade und Anwendungsfälle. Zum anderen soll durch das Modell ein automatisiertes Ableiten von Bepflanzungsplänen ermöglicht werden. Eine Analyse spezialisierter Softwareprodukte für die ‚Grüne Branche‘ gibt Aufschluss über die möglichen Funktionen der zu erstellenden Skripte in Dynamo. Der Workflow in Revit wird an einem Beispielprojekt veranschaulicht. Anhand eines Entwurfes für die Außenanlagen des Wohnkomplexes ‚Charlie Living‘ in Berlin wird somit ein vereinfachtes Modell angefertigt. Das Vegetationsmodell wird sukzessive für die Fertigstellungsgrade 100 bis 300 detailliert und enthält Bepflanzungselemente für Bäume, Hecken, Stauden und Pflanzflächen. Die Vegetationselemente werden mit zusätzlichen alphanumerischen Daten versehen und abschließend in einem Bepflanzungsplan dargestellt. Der Modellierungsprozess wird insgesamt mit zehn verschiedenen benutzerdefinierten Dynamo-Tools unterstützt und automatisiert. Anhand des Modellierungserfolges konnte eine generelle Eignung der BIM-Software Revit für die Anforderungen der Bepflanzungsplanung festgestellt werden. Die dargelegten Workflows in dieser Abschlussarbeit könnten demnach auch für das Modellieren von Vegetationsobjekten in anderen BIM-Projekten mit vergleichbarer Software Anwendung finden.
The mineralization of soil organic nitrogen (N) and crop residues can significantly contribute to the N supply of vegetable crops. However, short-term mineralization dynamics are difficult to predict. On the other hand, fast-growing crops like spinach are highly sensitive to N shortage. Therefore, in situ soil columns have been tested to estimate the actual N supply via mineralization in field-grown spinach. In ten fertilization trials covered soil columns (20 cm in diameter) were driven into the soil to a depth of 30 cm at the start of the cultivation. Eight columns were repeated in three blocks within a total trial area of 0.10 to 0.25 ha. Net N mineralization was derived by subtracting the soil mineral N concentration (Nmin) in the upper 30 cm before installation from the concentration inside the columns at harvest. For comparison, a balance sheet was calculated for spinach plots receiving no N fertilization (zero plots) as well as fertilized plots and used as a proxy for net N mineralization. In this approach the initial Nmin concentration in the upper 30 cm of the soil, the N supply via irrigation, and fertilization as well as the total aboveground N uptake by spinach and the Nmin residue were considered. By using soil columns, N mineralization was determined with a mean coefficient of variation of 18%. A higher spatial variability of up to 43% was observed when spinach was grown as a second crop. The average net N mineralization rate ranged between 2 kg ha‑1 week‑1 (0-30 cm) in winter-grown spinach and 3-7 kg ha‑1 week‑1 (0-30 cm) in the other seasons. Nitrogen mineralization measured by the soil columns was qualitatively confirmed with the data obtained by the balance sheet. Soil columns enable repeated samplings during the spinach cultivation. In this way, top dressing rates can be adjusted to the actual N supply.
Spinach is a nitrogen (N)-demanding crop characterized by a shallow root architecture. Especially in the first weeks after sowing, significant N uptake is limited to the uppermost few centimetres of the soil. However, base fertilization is usually based on the soil mineral N (Nmin) concentration in the upper 30 cm. Therefore, the objective of this study was to examine whether the soil sample depth for calculating the base N fertilization can be reduced to the 0-15 cm layer. In seven field trials, conducted during spring, summer and autumn seasons, either a low or high base fertilization dose was applied at sowing. Until top dressing, soil samples were frequently taken in the upper 0-15 and 15-30 cm layers to determine the average Nmin concentration in each layer. Top dressing was applied when the first true leaves had unfurled. With this fertilizer application, the total N supply was aligned between both treatments based on the Nmin concentration in the upper 30 cm of the soil. Aboveground fresh and dry masses were determined after reaching a fresh mass yield of 15-20 t ha‑1 and related to the mean Nmin concentration in the first 3 to 4 weeks of cultivation between sowing and top dressing. It was shown that the Nmin concentration in the upper 0-15 cm of the soil highly reflects the base fertilization rate. By contrast, the Nmin concentration in the 15-30 cm layer remained unaffected. However, the Nmin concentration of both top soil layers can affect fresh and dry mass yield at harvest. Therefore, the entire 0-30 cm soil layer should be considered when calculating the base N fertilization rate in field-grown spinach. Measurements revealed that spinach fresh and dry masses were increased until the N availability of between 54 and 59 kg ha‑1 (0-30 cm) was reached at the seedlings stage, respectively.
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.
Dieses Kapitel behandelt Marktforschungsansätze zur Wirkungsanalyse unternehmerischer Nachhaltigkeitshandlungen auf Endverbrauchermärkten. Ziel ist ein Überblick über Methoden, die aufgrund moderater Budgetvoraussetzungen in KMU und der angewandten Wissenschaft eingesetzt werden können. Dabei werden Herausforderungen der Messung ökologischer, sozialer und ethischer Kaufeigenschaften besonders berücksichtigt.
Primary Liver Cancers : Connecting the Dots of Cellular Studies and Epidemiology with Metabolomics
(2023)
Liver cancers are rising worldwide. Between molecular and epidemiological studies, a research gap has emerged which might be amenable to the technique of metabolomics. This review investigates the current understanding of liver cancer’s trends, etiology and its correlates with existing literature for hepatocellular carcinoma (HCC), cholangiocarcinoma (CCA) and hepatoblastoma (HB). Among additional factors, the literature reports dysfunction in the tricarboxylic acid metabolism, primarily for HB and HCC, and point mutations and signaling for CCA. All cases require further investigation of upstream and downstream events. All liver cancers reported dysfunction in the WNT/β-catenin and P13K/AKT/mTOR pathways as well as changes in FGFR. Metabolites of IHD1, IDH2, miRNA, purine, Q10, lipids, phosphatidylcholine, phosphatidylethanolamine, acylcarnitine, 2-HG and propionyl-CoA emerged as crucial and there was an attempt to elucidate the WNT/β-catenin and P13K/AKT/mTOR pathways metabolomically.
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.
Grasslands are ubiquitous globally, and their conservation and restoration are critical to combat both the biodiversity and climate crises. There is increasing interest in implementing effective multifunctional grassland restoration to restore biodiversity concomitant with above- and belowground carbon sequestration, delivery of carbon credits and/or integration with land dedicated to solar panels. Other common multifunctional restoration considerations include improved forage value, erosion control, water management, pollinator services, and wildlife habitat provisioning. In addition, many grasslands are global biodiversity hotspots. Nonetheless, relative to their impact, and as compared to forests, the importance of preservation, conservation, and restoration of grasslands has been widely overlooked due to their subtle physiognomy and underappreciated contributions to human and planetary well-being. Ultimately, the global success of carbon sequestration will depend on more complete and effective grassland ecosystem restoration. In this review, supported by examples from across the Western world, we call for more strenuous and unified development of best practices for grassland restoration in three areas of concern: initial site conditions and site preparation; implementation of restoration measures and management; and social context and sustainability. For each area, we identify the primary challenges to grassland restoration and highlight case studies with proven results to derive successful and generalizable solutions.
Advances in high-throughput DNA sequencing have propelled research into the human microbiome and its link to metabolic health. We explore microbiome analysis methods, specifically emphasizing metabolomics, how dietary choices impact the production of microbial metabolites, providing an overview of studies examining the connection between enterotypes and diet, and thus, improvement of personalized dietary recommendations. Acetate, propionate, and butyrate constitute more than 95% of the collective pool of short-chain fatty acids. Conflicting data on acetate’s effects may result from its dynamic signaling, which can vary depending on physiological conditions and metabolic phenotypes. Human studies suggest that propionate has overall anti-obesity effects due to its well-documented chemistry, cellular signaling mechanisms, and various clinical benefits. Butyrate, similar to propionate, has the ability to reduce obesity by stimulating the release of appetite-suppressing hormones and promoting the synthesis of leptin. Tryptophan affects systemic hormone secretion, with indole stimulating the release of GLP-1, which impacts insulin secretion, appetite suppression, and gastric emptying. Bile acids, synthesized from cholesterol in the liver and subsequently modified by gut bacteria, play an essential role in the digestion and absorption of dietary fats and fat-soluble vitamins, but they also interact directly with intestinal microbiota and their metabolites. One study using statistical methods identified primarily two groupings of enterotypes Bacteroides and Ruminococcus. The Prevotella-dominated enterotype, P-type, in humans correlates with vegetarians, high-fiber and carbohydrate-rich diets, and traditional diets. Conversely, individuals who consume diets rich in animal fats and proteins, typical in Western-style diets, often exhibit the Bacteroides-dominated, B-type, enterotype. The P-type showcases efficient hydrolytic enzymes for plant fiber degradation but has limited lipid and protein fermentation capacity. Conversely, the B-type features specialized enzymes tailored for the degradation of animal-derived carbohydrates and proteins, showcasing an enhanced saccharolytic and proteolytic potential. Generally, models excel at predictions but often struggle to fully elucidate why certain substances yield varied responses. These studies provide valuable insights into the potential for personalized dietary recommendations based on enterotypes
SimBO is a flexible framework for optimizing discrete event-driven simulations (DES) using sequential optimization algorithms. While specifically designed for Bayesian Optimization (BO) in the context of DES, SimBO can be applied to any black-box problem with other optimization algorithms. The framework consists of four encapsulated components - the black-box problem, the sequential optimization algorithm, a database for experiment configuration and results, and a web-based graphical user interface - that communicate via well-defined interfaces. Each component can be run in different environments, allowing for cooperation between different hardware- and software configurations. In our research context, SimBO’s architecture enabled BO algorithms to be run on a high-performance cluster with GPU support, while the simulation is executed on a local Windows machine using the Simio simulation software. The framework’s flexibility also makes it suitable for evolving from a research-focused tool to a production-ready, cloud-based optimization tool for modern algorithms.