184 research outputs found
Network governance and regional resilience to climate change: empirical evidence from mountain tourism communities in the Swiss Gotthard region
Mountain regions and peripheral communities, which often depend on few economic sectors, are among the most exposed and sensitive to climate change. Governance of such socio-economic-ecological networks plays a strong role in determining their resilience. Social processes of governance, such as collaboration between communities, can be systematically assessed through the existence and strength of connections between actors and their embeddedness in the broader socio-economic network by social network analysis (SNA). This paper examines how network governance of the tourism industry-dependent Swiss Gotthard region relates to resilience to climate change by SNA. The paper argues that economic diversification and a network structure supporting stability, flexibility, and innovation increase regional resilience to climate change. The Gotthard network has a high diversification capability due to high cohesion and close collaboration, limited innovative capacity by the existence of only two subgroups, and considerable flexibility through the centralized structure. Main weaknesses are a low density, uneven distribution of power, and a lack of integration of some supply chain sectors into the overall networ
Braucht Biowein weniger Energie? - Ăkobilanzierung von Bioweinen
Gesamtbetriebliche EnergieflĂŒsse werden erfasst um die Umweltwirkungen europĂ€ischer Bioweine zu beurteilen (Traubenproduktion, Kelterung, Transport). Ziel ist, den ökologischen âFussabdruckâ der Betriebe zu bestimmen und Massnahmen fĂŒr die Verbesserung zu erarbeiten
GMA: A Pareto Optimal Distributed Resource-Allocation Algorithm
To address the rising demand for strong packet delivery guarantees in
networking, we study a novel way to perform graph resource allocation. We first
introduce allocation graphs, in which nodes can independently set local
resource limits based on physical constraints or policy decisions. In this
scenario we formalize the distributed path-allocation (PAdist) problem, which
consists in allocating resources to paths considering only local on-path
information -- importantly, not knowing which other paths could have an
allocation -- while at the same time achieving the global property of never
exceeding available resources.
Our core contribution, the global myopic allocation (GMA) algorithm, is a
solution to this problem. We prove that GMA can compute unconditional
allocations for all paths on a graph, while never over-allocating resources.
Further, we prove that GMA is Pareto optimal with respect to the allocation
size, and it has linear complexity in the input size. Finally, we show with
simulations that this theoretical result could be indeed applied to practical
scenarios, as the resulting path allocations are large enough to fit the
requirements of practically relevant applications
Effect of extrusion processing parameters on structure, texture and dietary fibre composition of directly expanded wholegrain oat-based matrices
Oat flour mixed with 30 g/100 g rice flour was extruded with a twin-screw extruder using a central composite orthogonal design. Temperatures (120 °C,140 °C, 160 °C) and moisture (14.5 g/100 g, 17.7 g/100 g, 20.6 g/100 g) were adjusted during extrusion, while screw speed was kept constant (400 rpm). Extrudates were analysed for structure (expansion, density, microstructure), texture (hardness), ÎČ-glucan (molecular weight and extractability), as well as fibre content. Expansion varied between 250 and 329%, density between 165 and 457 kg/m3 and hardness between 27 and 64 N. The response surface model showed that more expanded, less dense and less hard extrudates were achieved at low moisture, while high temperature resulted in lower density and hardness. Significant differences in ÎČ-glucan extractability were observed depending on extrusion conditions, with values ranging between 0.64 and 1.31 g/100 g. ÎČ-glucan extractability correlated with positively with porosity, and negatively with moisture content during extrusion, cell wall thickness and density. The results indicate that conditions that produce a more porous, crispier structure, also increases ÎČ-glucan extractability.ISSN:0460-1173ISSN:0023-6438ISSN:1096-112
Ăkodumping : Mythos oder RealitĂ€t
1. Einleitung 1.1. Motivation Im Zuge der Globalisierung der Weltwirtschaft einerseits und den weltweit wachsenden Umweltproblemen andererseits stellt sich die Frage nach der Rolle der multinationalen Konzerne im Prozess einer ânachhaltigen Entwicklungâ. Unternehmen reagieren auf die Globalisierung der MĂ€rkte mit einer zunehmenden Internationalisierung ihrer Informatlonsâ, Finanzâ, Investitionsâ, Produktionsâ und AbsatzaktivitĂ€ten. Mit dieser Internationalisierungsstrategle streben die Untern..
Gradient-enhanced volume rendering: an image processing strategy to facilitate whole small bowel imaging with MRI
MRI of the small bowel with positive contrast from orally administered contrast agent is a promising non-invasive imaging method. The aim of our study was to introduce small bowel MRI in a display format that clinicians are accustomed to and that maximizes the amount of information visualized on a single image. Twelve healthy volunteers, median age 32years (range 18-49 years) participated in the study. A mixture of 20ml Gd-DOTA (Dotarem), 0.8g/kg body weight psyllium fibre (Metamucil) and 1.2l water were sequentially administered over a period of 4h. Imaging was performed on a 1.5Tunit (Philips Gyroscan, Intera). Fat-saturated, 3D, gradient echo imaging was performed while the patient was in apnea (30s). Bowel motion was reduced with 40mg intravenously administered scopolamine (Buscopan). A 3D, gradient-enhanced, volume rendering technique was applied to the 3D data sets. Standard projections [left anterior oblique (LAO), right anterior oblique (RAO), supine and prone] resembling conventional enteroclysis were successfully generated within fewer than 10min processing time. Reconstructions were reproducible and provided an entire overview of the small bowel. In addition thin-slab volume rendering allowed an overlap-free display of individual structures. Positive contrast from orally administered contrast agent, combined with a gradient enhanced volume rendering method, allows the reconstruction of the small bowel in a pattern resembling conventional double-contrast enteroclysis. Segmental display without overlay is possibl
The Influence of the Degree of Heterogeneity on the Elastic Properties of Random Sphere Packings
The macroscopic mechanical properties of colloidal particle gels strongly
depend on the local arrangement of the powder particles. Experiments have shown
that more heterogeneous microstructures exhibit up to one order of magnitude
higher elastic properties than their more homogeneous counterparts at equal
volume fraction. In this paper, packings of spherical particles are used as
model structures to computationally investigate the elastic properties of
coagulated particle gels as a function of their degree of heterogeneity. The
discrete element model comprises a linear elastic contact law, particle bonding
and damping. The simulation parameters were calibrated using a homogeneous and
a heterogeneous microstructure originating from earlier Brownian dynamics
simulations. A systematic study of the elastic properties as a function of the
degree of heterogeneity was performed using two sets of microstructures
obtained from Brownian dynamics simulation and from the void expansion method.
Both sets cover a broad and to a large extent overlapping range of degrees of
heterogeneity. The simulations have shown that the elastic properties as a
function of the degree of heterogeneity are independent of the structure
generation algorithm and that the relation between the shear modulus and the
degree of heterogeneity can be well described by a power law. This suggests the
presence of a critical degree of heterogeneity and, therefore, a phase
transition between a phase with finite and one with zero elastic properties.Comment: 8 pages, 6 figures; Granular Matter (published online: 11. February
2012
Feruloylputrescine and Caffeoylputrescine Are Not Involved in Growth and Floral Bud Formation of Stem Explants from Nicotiana tabacum
Complement receptor 2 is expressed in neural progenitor cells and regulates adult hippocampal neurogenesis
Injury and inflammation are potent regulators of adult neurogenesis. As the complement system forms a key immune pathway that may also exert critical functions in neural development and neurodegeneration, we asked if complement receptors regulate neurogenesis. We discovered that complement receptor 2 (CR2), classically known as a co-receptor of the B lymphocyte antigen receptor, is expressed in adult neural progenitor cells (NPCs) of the dentate gyrus. Two of its ligands, C3d and interferon-α (IFN-α), inhibited proliferation of wildtype NPCs but not NPCs derived from mice lacking Cr2 (Cr2(â/â)) indicating functional Cr2 expression. Young and old Cr2(â/â) mice exhibited prominent increases in basal neurogenesis compared with wildtype littermates, while intracerebral injection of C3d resulted in fewer proliferating neuroblasts in wildtype than in Cr2(â/â) mice. We conclude that Cr2 regulates hippocampal neurogenesis and propose that increased C3d and IFN-α production associated with brain injury or viral infections may inhibit neurogenesis
Activation of sea-urchin sperm motility is accompanied by an increase in the creatine kinase exchange flux
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