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.

Localization of phytosiderophore release and of iron uptake along intact barley roots

Abstract: Under iron deficiency the release of so-called phytosiderophores by roots of barley plants (Hordeum vulgare L. cv. Europa) was greater by a factor of 10 to 50 compared to iron-sufficient plants. This enhanced release occurred particularly in apical zones of the seminal roots and in the lateral root zones. Under iron deficiency, uptake rates for iron, supplied as FeIII phytosiderophore, increased by a factor of ca 5 as compared to iron-sufficient plants. This enhanced uptake rate for iron was also much more pronounced in apical than in basal root zones. In contrast, with supply of the synthetic iron chelate, FelII EDDHA (ferric diaminoethane-N, N-di-o-hydroxyphenyl acetic acid), the Fe deficiency-enhanced uptake rates for iron were only small and similar along the roots, except for the lateral root zones. The high selectivity of barley roots for uptake and translocation of FeIII phytosiderophores compared with FeIII EDDHA is reflected by the fact that, at the same external concentration (2 μM), rates of uptake and translocation of iron from FeIII phytosiderophores were between 100 (Fe-sufficient) and 1 000 times higher (Fe-deficient plants) than from FeIII EDDHA. The relatively high rates of uptake and particularly of translocation of iron supplied as FeIII EDDHA in the zone of lateral root formation strongly suggest an apoplastic pathway of radial transport of the synthetic iron chelate into the stele in this root zone. The results demonstrate that apical root zones are the main sites both for Fe deficiency-enhanced release of phytosiderophores and for uptake and translocation of iron supplied as FeIII phytosiderophores.

Cell Movements at Hensen’s Node Establish Left/Right Asymmetric Gene Expression in the Chick

Abstract: In vertebrates, the readily apparent left/right (L/R) anatomical asymmetries of the internal organs can be traced to molecular events initiated at or near the time of gastrulation However, the earliest steps of this process do not seem to be universally conserved In particular, how this axis is first defined in chicks has remained problematic Here we show that asymmetric cell rearrangements take place within chick embryos, creating a leftward movement of cells around the node It is the relative displacement of cells expressing sonic hedgehog (Shh) and fibroblast growth factor 8 (Fgf8) that is responsible for establishing their asymmetric expression patterns The creation of asymmetric expression domains as a passive effect of cell movements represents an alternative strategy for breaking L/R symmetry in gene activity

The Ethical Rational of Business for the Poor – Integrating the Concepts Bottom of the Pyramid, Sustainable Development and Corporate Citizenship

Abstract: The first United Nations Millennium Development Goal calls for a distinct reduction of worldwide poverty. It is now widely accepted that the private sector is a crucial partner in achieving this ambitious target. Building on this insight, the ‘Bottom of the Pyramid’ concept provides a framework that highlights the untapped opportunities with the ‘poorest of the poor,’ while at the same time acknowledging the abilities and resources of private enterprises for poverty alleviation.This paper connects the idea of business with the poor to sustainable development and especially to the notions of inter- and intragenerational justice. These principles of justice can be linked with the ‘Bottom of the Pyramid’ approach directly through the Rawlsian principles to foster holistic thinking. On this basis, the paper offers a normative-ethical reasoning of corporations’ possible responsibilities for the poorest of the poor. Today’s state of worldwide inequalities is likely to generate future tensions between the privileged western world and the uncounted mass of poor (let alone the ethical dubiousness of this status). However, it is at the same time problematic if not even impossible to improve the situation of the poor by simply copying the resource intensive western way of living to the ‘Bottom of the Pyramid’ due to the limited carrying capacity of the earth. After highlighting possible moral dilemmas which may occur through such a potential trade off, this paper concludes with an outlook on how the concepts ‘Bottom of the Pyramid’ and sustainable development could be combined.