112 research outputs found
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Evaluation of different sensing approaches concerning to nondestructive estimation of leaf area index (LAI) for winter wheat
Different approaches of non-destructive estimation of the LAI in winter wheat were compared. Plant height had weak relation with the LAI, while estimated biomass showed high logarithmic relationship (R2=0.839). NDRE and REIP were logarithmically well related to the LAI (R2=0.726 and 0.779 respectively). Saturation effect of NDRE and REIP was less than NDVI. Some RGB-based indices also showed good potential to estimate the LAI. Among the indices, Gm, GMB, RMB, and NRMB were better related to the LAI. The results indicated that digital cameras can be used as an affordable and simple approach for assessment of the LAI of crops
Standortspezifische Modellierung von Pflanzenwachstum, Wasser- und N-Dynamik auf der Basis hochaufgelöster Bodensensordaten
Die Berücksichtigung von Bodenunterschieden innerhalb von Ackerschlägen bei der Bemessung von Düngergaben kann zu einer höheren Effizienz von Düngermaßnahmen führen, wenn einerseits Ertragspotentiale genutzt und andererseits Überdüngungen vermieden werden. Die technischen Möglichkeiten des Precision Agriculture werden jedoch bislang nur zögerlich genutzt, da die Erhebung der räumlichen Variabilität von Bodeneigenschaften mit erheblichem Aufwand verbunden ist und betriebswirtschaftlich wenig lohnend erscheint. Im BoNaRes Projekt I4S werden verschiedene Verfahren der Bodensensorik zur Erfassung wesentlicher Merkmale entwickelt und mit Modellen und Entscheidungsunterstützungsalgorithmen verknüpft.
Erste Ergebnisse, die das Potential einer auf hochaufgelösten Bodendaten basierenden Simulation von Pflanzenwachstum sowie Bodenwasser und-Stickstoffdynamik im Vergleich mit hochaufgelösten Ertragskarten zeigen, werden vorgestellt. Diese basieren zunächst auf der bereits etablierten Messung der elektrischen Leitfähigkeit (EM-38) und der Nutzung von konventionell untersuchten Bodenproben in einem 50 m Raster. Hieraus lassen sich hochaufgelöste Karten zur Verteilung von Textur und Humusgehalt als Modelleingangsgrößen für 5000 Punkte innerhalb eines 20 ha Schlages ableiten. Die Konsistenz der Modellrechnungen wird anhand von Erträgen, Bodenwasser- und Nmin-Gehalten an 60 Rasterpunkten über drei Vegetationsperioden geprüft. Der Effekt unterschiedlicher Aggregierung sowohl von Boden als auch Ertragsdaten wird dargestellt
The Level of Protein in Milk Formula Modifies Ileal Sensitivity to LPS Later in Life in a Piglet Model
Background: Milk formulas have higher protein contents than human milk. This high protein level could modify the development of intestinal microbiota, epithelial barrier and immune functions and have long-term consequences. Methodology/Principal findings: We investigated the effect of a high protein formula on ileal microbiota and physiology during the neonatal period and later in life. Piglets were fed from 2 to 28 days of age either a normoprotein (NP, equivalent to sow milk) or a high protein formula (HP, +40% protein). Then, they received the same solid diet until 160 days. During the formula feeding period ileal microbiota implantation was accelerated in HP piglets with greater concentrations of ileal bacteria at d7 in HP than NP piglets. Epithelial barrier function was altered with a higher permeability to small and large probes in Ussing chambers in HP compared to NP piglets without difference in bacterial translocation. Infiltration of T cells was increased in HP piglets at d28. IL-1b and NF-kappa B sub-units mRNA levels were reduced in HP piglets at d7 and d28 respectively; plasma haptoglobin also tended to be reduced at d7. Later in life, pro-inflammatory cytokines secretion in response to high doses of LPS in explants culture was reduced in HP compared to NP piglets. Levels of mRNA coding the NF-kappa B pathway sub-units were increased by the challenge with LPS in NP piglets, but not HP ones. Conclusions/Significance: A high protein level in formula affects the postnatal development of ileal microbiota, epithelial barrier and immune function in piglets and alters ileal response to inflammatory mediators later in life
Protocol of the HISTOTHERM study: assessing the response to hyperthermia and hypofractionated radiotherapy in recurrent breast cancer
IntroductionBreast cancer is globally the leading cancer in women, and despite the high 5-year survival rate the most frequent cause of cancer related deaths. Surgery, systemic therapy and radiotherapy are the three pillars of curative breast cancer treatment. However, locoregional recurrences frequently occur after initial treatment and are often challenging to treat, amongst others due to high doses of previous radiotherapy treatments. Radiotherapy can be combined with local hyperthermia to sensitize tumor cells to radiation and thereby significantly reduce the required radiation dose. Therefore, the combination treatment of mild local hyperthermia, i.e. locally heating of the tissue to 39-43°C, and re-irradiation with a reduced total dose is a relevant treatment option for previously irradiated patients. The mechanisms of this effect in the course of the therapy are to date not well understood and will be investigated in the HISTOTHERM study.Methods and analysesPatients with local or (loco)regional recurrent breast cancer with macroscopic tumors are included in the study. Local tumor control is evaluated clinically and histologically during the course of a combination treatment of 60 minutes mild superficial hyperthermia (39 - 43°C) using water-filtered infrared A (wIRA) irradiation, immediately followed by hypofractionated re-irradiation with a total dose of 20-24 Gy, administered in weekly doses of 4 Gy. Tumor and tumor stroma biopsies as well as blood samples will be collected prior to treatment, during therapy (at a dose of 12 Gy) and in the follow-up to monitor therapy response. The treatment represents the standard operating procedure for hyperthermia plus re-irradiation. Various tissue and blood-based markers are analyzed. We aim at pinpointing key mechanisms and markers for therapy response which may help guiding treatment decisions in future. In addition, quality of life in the course of treatment will be assessed and survival data will be evaluated.RegistrationThe study is registered at the German Clinical Trials Register, Deutsches Register Klinischer Studien (DRKS00029221)
An ecological future for weed science to sustain crop production and the environment. A review
Sustainable strategies for managing weeds are critical to meeting agriculture's potential to feed the world's population while conserving the ecosystems and biodiversity on which we depend. The dominant paradigm of weed management in developed countries is currently founded on the two principal tools of herbicides and tillage to remove weeds. However, evidence of negative environmental impacts from both tools is growing, and herbicide resistance is increasingly prevalent. These challenges emerge from a lack of attention to how weeds interact with and are regulated by the agroecosystem as a whole. Novel technological tools proposed for weed control, such as new herbicides, gene editing, and seed destructors, do not address these systemic challenges and thus are unlikely to provide truly sustainable solutions. Combining multiple tools and techniques in an Integrated Weed Management strategy is a step forward, but many integrated strategies still remain overly reliant on too few tools. In contrast, advances in weed ecology are revealing a wealth of options to manage weedsat the agroecosystem levelthat, rather than aiming to eradicate weeds, act to regulate populations to limit their negative impacts while conserving diversity. Here, we review the current state of knowledge in weed ecology and identify how this can be translated into practical weed management. The major points are the following: (1) the diversity and type of crops, management actions and limiting resources can be manipulated to limit weed competitiveness while promoting weed diversity; (2) in contrast to technological tools, ecological approaches to weed management tend to be synergistic with other agroecosystem functions; and (3) there are many existing practices compatible with this approach that could be integrated into current systems, alongside new options to explore. Overall, this review demonstrates that integrating systems-level ecological thinking into agronomic decision-making offers the best route to achieving sustainable weed management
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