University of Hohenheim

About: University of Hohenheim is a education organization based out in Stuttgart, Germany. It is known for research contribution in the topics: Population & Soil water. The organization has 8585 authors who have published 16406 publications receiving 567377 citations.

Die Informationsverarbeitung tympanaler Rezeptorelemente vonLocusta migratoria (Acrididae, Orthoptera)

Abstract: 1. The reactions of tympanic nerve fibers ofLocusta migratoria were recorded by glass microelectrodes in the metathoracic ganglion. 2. The units were classified by frequency-, intensity-, and directional characteristics as well as by their response pattern. The response to speciesspecific song is compared with the response to song ofEphippiger ephippiger. 3. The physiological properties lead to a classification into three types of low-frequency neurons (characteristic frequency 3.5–4 kHz; 4kHz; 5.5–6 kHz) and one type of high-frequency neuron (12–20 kHz). This is similar to other species (Gray, 1960, Michelsen, 1971). 4. Intensity-coding is done by sharp rising intensity characteristics and by different absolute thresholds of the units. 5. There is a marked directional sensitivity with some differences between LF and HF units. In the low frequency range the tympanal organ seems to react as a pressure gradient receiver; for high frequencies another mechanism is discussed. 6. No filtering of species-specific song takes place at the level of the receptor cells.

Cannibalization or Synergy? Consumers’ Channel Selection in Online-Offline Multichannel Systems

Abstract: This paper develops and empirically validates customer shopping motives taking account of customer channel selection in multichannel systems. As each channel is associated with certain advantages and disadvantages from a customer’s perspective, we develop – based on behavioral considerations – a customer typology to classify different segments of customers. This enables us to empirically analyze the interrelationship between distinct shopping motives prior marketing research has suggested and cannibalization and synergetic effects in online–offline multichannel systems. Our results show that a higher degree of customers’ convenience orientation in contrast to the degree of risk aversion and service orientation encourages the selection of the online channel over the offline channel. In addition, we develop and empirically analyze a typology of customers to classify distinct segments of consumers, highlighting the associated interrelationship of individual shopping motives and cannibalization and synergetic effects. Our results indicate that the desire for service, rather than risk aversion, could potentially cannibalize customers away from the online channel.

The content of phenolic compounds and radical scavenging activity varies with carrot origin and root color

Abstract: The contents of phenolic compounds and radical scavenging activities were assessed in a carrot collection comprising 35 cultivars, landraces and breeding populations. The accessions originated from various world regions and they represented Eastern and Western carrot gene pools. In two-year field trial carrot roots of orange, red, yellow, white and purple color were cultivated, freeze-dried and analyzed for phenolic content by Folin-Ciocalteu assay and UV/Vis assay. Radical scavenging activity in the extracts was determined with a stable DPPH radical. Carrots developing purple roots possessed on average 9 times more phenolics than roots of other colors. Furthermore, they were rich in anthocyanins that caused very high antiradical activity. Red carrots showed higher antioxidant activity than orange, yellow and white carrots and in the season of lower rainfall they accumulated higher amounts of phenolic compounds. Carrots of Asian origin belonging to Eastern gene pool were more often purple or red and richer in phenolics and had higher antiradical activity than those from the Western gene pool with mainly orange roots.

Herbicides and plant hormesis.

Abstract: Herbicide hormesis is commonly observed at subtoxic doses of herbicides and other phytotoxins. The occurrence and magnitude of this phenomenon are influenced by plant growth stage and physiological status, environmental factors, the endpoint measured and the timing between treatment and endpoint measurement. The mechanism in some cases of herbicide hormesis appears to be related to the target site of the herbicide, whereas in other examples hormesis may be by overcompensation to moderate stress induced by the herbicides or a response to disturbed homeostasis. Theoretically, herbicide hormesis could be used in crop production, but this has been practical only in the case of the use of herbicides as sugar cane ‘ripeners’ to enhance sucrose accumulation. The many factors that can influence the occurrence, the magnitude and the dose range of hormetic increases in yield for most crops make it too unpredictable and risky as a production practice with the currently available knowledge. Herbicide hormesis can cause undesired effects in situations in which weeds are unintentionally exposed to hormetic doses (e.g. in adjacent fields, when shielded by crop vegetation). Some weeds that have evolved herbicide resistance may have hormetic responses to recommended herbicide application rates. Little is known about such effects under field conditions. A more complete understanding of herbicide hormesis is needed to exploit its potential benefits and to minimize its potential harmful effects in crop production. © 2014 Society of Chemical Industry