Random close packing of granular matter

We propose an interpretation of the random close packing of granular materials as a phase transition, and discuss the possibility of experimental verification.Comment: 6 page

An environmental justice perspective on ecosystem services

Mainstreaming of ecosystem service approaches has been proposed as one path toward sustainable development. Meanwhile, critics of ecosystem services question if the approach can account for the multiple values of ecosystems to diverse groups of people, or for aspects of inter- and intra-generational justice. In particular, an ecosystem service approach often overlooks power dimensions and capabilities that are core to environmental justice. This article addresses the need for greater guidance on incorporating justice into ecosystem services research and practice. We point to the importance of deep engagement with stakeholders and rights holders to disentangle contextual factors that moderate justice outcomes on ecosystem service attribution and appropriation in socio-political interventions. Such a holistic perspective enables the integration of values and knowledge plurality for enhancing justice in ecosystem services research. This broadened perspective paves a way for transformative ecosystem service assessments, management, and research, which can help inform and design governance structures that nourish human agency to sustainably identify, manage, and enjoy ecosystem services for human wellbeing

Muss guter Rat teuer sein?

Ausgehend von einer umfragegestützten Analyse der aktuellen Herausforderungen des deutschen Archivwesens im Allgemeinen und des katholischen Archivwesens im Besonderen fragt die Arbeit, ob im katholischen Archivwesen Bedarf für die Einrichtung einer zentralen Beratungsstelle besteht und ob eine solche den katholischen Archiven dabei helfen könnte, die aktuellen Herausforderungen (besser) zu meistern. Sie definiert weiterhin die Anforderungen an eine mögliche Archivberatungsstelle hinsichtlich Zielgruppe, fachlicher Ausrichtung, finanzieller und personeller Ausstattung sowie Organisationsform. Die Arbeit gelangt zu dem Ergebnis, dass Beratungs- und Unterstützungsbedarf insbesondere in den Bereichen der Digitalisierung und digitalen Bereitstellung, der digitalen Langzeitarchivierung sowie auf dem Gebiet der archivarischen Aus- und Fortbildung besteht und die Einrichtung einer Beratungs- und Koordinierungsstelle für katholische Diözesanarchive, die Archive der katholischen Vereine und Verbände sowie die Archive der Orden sinnvoll wäre

Basic nanostructure of stratum corneum lipid matrices based on ceramides [EOS] and [AP] a neutron diffraction study

The goal of this study was to investigate the nanostructure of SC lipid model membranes comprising the most relevant SC lipids such as the unique structured omega acylceramide [EOS] in a near natural ratio with neutron diffraction. In models proposed recently the presence of ceramide [EOS] and FFA are necessary for the formation of one of the two existent crystalline lamellar phases of the SC lipids, the long periodicity phase as well as for the normal barrier function of the SC. The focus of this study was placed on the influence of the FFA BA on the membrane structure and its localization within the membrane based on the ceramides [EOS] and [AP]. The internal nanostructure of such membranes was obtained by Fourier synthesis from the experimental diffraction patterns. The resulting neutron scattering length density profiles showed that the exceptionally long ceramide [EOS] is arranged in a short periodicity phase created by ceramide [AP] by spanning through the whole bilayer and extending even further into the adjacent bilayer. Specifically deuterated BA allowed us to determine the exact position of this FFA inside this SC lipid model membrane. Furthermore, hydration experiments showed that the presented SC mimic system shows an extremely small intermembrane hydration of approximately 1 A, consequently the headgroups of the neighboring leaflets are positioned close to each othe

Direct electron irradiation of DNA in a fully aqueous environment. Damage determination in combination with Monte Carlo simulations

We report on a study in which plasmid DNA in water was irradiated with 30 keV electrons generated by a scanning electron microscope and passed through a 100 nm thick Si3N4 membrane. The corresponding Monte Carlo simulations suggest that the kinetic energy spectrum of the electrons throughout the water is dominated by low energy electrons (<100 eV). The DNA radiation damage, single-strand breaks (SSBs) and double-strand breaks (DSBs), was determined by gel electrophoresis. The median lethal dose of D-1/2 = 1.7 +/- 0.3 Gy was found to be much smaller as compared to partially or fully hydrated DNA irradiated under vacuum conditions. The ratio of the DSBs to SSBs was found to be 1 : 12 as compared to 1 : 88 found for hydrated DNA. Our method enables quantitative measurements of radiation damage to biomolecules (DNA, proteins) in solutions under varying conditions (pH, salinity, co-solutes) for an electron energy range which is difficult to probe by standard methods