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Nitrogen turnover in a repeatedly manured arid subtropical soil: Incubation studies with 15N isotopes
(2019-07-23)
Under the hot and moist conditions of irrigated agriculture in the arid subtropics, turnover of organic matter is high, which can lead to considerable carbon (C) and nitrogen (N) losses. Therefore, sustainable use of these soils requires regular manure application at high rates. To investigate the contribution of consecutive manure applications to an arid sandy soil to various soil N pools, goat manure was isotopically labeled by feeding 15N‐enriched Rhodes grass hay and applied to the soil during a two‐year field ...
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The effect of biodynamic preparations on growth and fruit quality of giant pumpkin (Cucurbita maxima D.)
(2021-11-25)
Background
Food quality of agricultural crops depends on environmental conditions, production system and cultivation method. A plant-based nutrition with food rich in vitamins, minerals and secondary plant compounds with antioxidative properties promotes human health. This investigation was inspired by an increasing global issue on how to improve product quality while using alternative preparations. The main aim of a 3-year study was to investigate the influence of fermented manure and silica products on yield and ...
Aufsatz
No Evidence for Ionotropic Pheromone Transduction in the Hawkmoth Manduca sexta
(2016-11-09)
Insect odorant receptors (ORs) are 7-transmembrane receptors with inverse membrane topology. They associate with the conserved ion channel Orco. As chaperon, Orco maintains ORs in cilia and, as pacemaker channel, Orco controls spontaneous activity in olfactory receptor neurons. Odorant binding to ORs opens OR-Orco receptor ion channel complexes in heterologous expression systems. It is unknown, whether this also occurs in vivo. As an alternative to this ionotropic transduction, experimental evidence is accumulating ...
Aufsatz
Sulfur transfer and activation by ubiquitin-like modifier system Uba4•Urm1 link protein urmylation and tRNA thiolation in yeast
(2016-10-24)
Urm1 is a unique dual-function member of the ubiquitin protein family and conserved from yeast to man. It acts both as a protein modifier in ubiquitin-like urmylation and as a sulfur donor for tRNA thiolation, which in concert with the Elongator pathway forms 5-methoxy-carbonyl-methyl-2-thio (mcm5s2) modified wobble uridines (U34) in anticodons. Using Saccharomyces cerevisiae as a model to study a relationship between these two functions, we examined whether cultivation temperature and sulfur supply previously ...
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Beyond spikes: Multiscale computational analysis of in vivo long-term recordings in the cockroach circadian clock
(2019-09-23)
The circadian clock of the nocturnal Madeira cockroach is located in the accessory medulla, a small nonretinotopic neuropil in the brain’s visual system. The clock comprises about 240 neurons that control rhythms in physiology and behavior such as sleep-wake cycles. The clock neurons contain an abundant number of partly colocalized neuropeptides, among them pigment-dispersing factor (PDF), the insects’ most important circadian coupling signal that controls sleep-wake rhythms. We performed long-term loose-patch clamp ...
Aufsatz
Angebot, Nutzung und Ertrag von Konzeptwechseltexten zu Neuromythen bei angehenden Biologielehrkräften
(2021-04-27)
Lehrkräftebildung hat das Ziel, Studierende zu Fachleuten für das Lehren und Lernen auszubilden. Empirische Studien zeigen jedoch sowohl bei angehenden als auch praktizierenden Lehrkräften eine hohe Zustimmung zu Fehlvorstellungen zum Thema Gehirn und Lernen – sogenannten Neuromythen. In der vorliegenden Studie wird in einem Mixed-Model-Design (N = 40) mit quantitativen und qualitativen Forschungsmethoden und vor dem theoretischen Hintergrund eines Angebots-Nutzungs-Modells untersucht, inwiefern sich durch eine ...
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Arthropod Communities in Urban Agricultural Production Systems under Different Irrigation Sources in the Northern Region of Ghana
(2020-08-01)
Urban and peri-urban agricultural (UPA) production systems in West African countries do not only mitigate food and financial insecurity, they may also foster biodiversity of arthropods and partly compensate for structural losses of natural environments. However, management practices in UPA systems like irrigation may also contribute to disturbances in arthropod ecology. To fill knowledge gaps in the relationships between UPA management and arthropod populations, we compared arthropods species across different irrigation ...
Aufsatz
Importance of sources of variability, scales and experimental design: A case study about the effects of biochar and slurry application on soil properties in agricultural silty loam soils
(2021-04-17)
In designed experiments, different sources of variability and an adequate scale of measurement need to be considered, but not all approaches in common usage are equally valid. In order to elucidate the importance of sources of variability and choice of scale, we conducted an experiment where the effects of biochar and slurry applications on soil properties related to soil fertility were studied for different designs: (a) for a field-scale sampling design with either a model soil (without natural variability) as an ...
Aufsatz
Phospholipid fatty acids in soil—drawbacks and future prospects
(2021-12-21)
The current opinion and position paper highlights (1) correct assignation of indicator phospholipid fatty acids (PLFA), (2) specificity and recycling of PLFA in microorganisms, and (3) complete extraction and detection of PLFA. The straight-chain PLFA 14:0, 15:0, 16:0, and 17:0 occur in all microorganisms, i.e., also in fungi and not only in bacteria. If the phylum Actinobacteria is excluded from the group of Gram-positive bacteria, all remaining bacteria belong to the bacterial phylum Firmicutes, which should be ...
Aufsatz
Neither per, nor tim1, nor cry2 alone are essential components of the molecular circadian clockwork in the Madeira cockroach
(2020-08-04)
Circadian clocks control rhythms in physiology and behavior entrained to 24 h light–dark cycles. Despite of conserved general schemes, molecular circadian clockworks differ between insect species. With RNA interference (RNAi) we examined an ancient circadian clockwork in a basic insect, the hemimetabolous Madeira cockroach Rhyparobia maderae. With injections of double-stranded RNA (dsRNA) of cockroach period (Rm´per), timeless 1 (Rm´tim1), or cryptochrome 2 (Rm´cry2) we searched for essential components of the clock´s ...