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Renewal through Participation in Global Food Security Governance: Implementing the International Food Security and Nutrition Civil Society Mechanism to the Committee on World Food Security
The food commodity price rises from 2006 to 2008 engendered a period of political renewal and reform in the governance of global food security. The Committee on World Food Security (CFS) was designated as the main international forum dealing with food security and nutrition in 2009 as part of this reform. Through the CFS reform process, civil society organizations secured the right to co-ordinate autonomously their engagement in the Committee as official participants and are doing so through the International Food Security and Nutrition Civil Society Mechanism (CSM). The CSM is an innovative institutional form designed to allow a broad range of civil society organizations from different regions of the world and from diverse constituencies, notably those who face food insecurity on a regular basis, to participate in global food security governance. The challenges and complexities of setting up and operationalizing the CSM are presented and illustrated. These findings are considered in the context of the longer-term move towards widening participation in global governance, with a particular focus on the trajectory of civil society participation in food security governance. The broad neo-liberal logic, or embedded neo-liberalism, that underpins contemporary world politics provides boundaries within which the innovative CSM is being given shape through the political agency of the participating civil society organizations. The study concludes by suggesting that while the Civil Society Mechanism faces some internal challenges, these are not insurmountable, and that the CSM represents an effective politicizing, engaging and connecting model for food-focused civil society organization entering into global governance
Two-dimensional structure in a generic model of triangular proteins and protein trimers
Motivated by the diversity and complexity of two-dimensional crystals formed
by triangular proteins and protein trimers, we have investigated the structures
and phase behavior of hard-disk trimers. In order to mimic specific binding
interactions, each trimer possesses on `attractive' disk which can interact
with similar disks on other trimers via an attractive square-well potential. At
low density and low temperature, the fluid phase mainly consists of tetramers,
pentamers, or hexamers. Hexamers provide the structural motif for a
high-density, low-temperature periodic solid phase, but we also identify a
metastable periodic structure based on a tetramer motif. At high density there
is a transition between orientationally ordered and disordered solid phases.
The connections between simulated structures and those of 2D protein crystals
-- as seen in electron microscopy -- are briefly discussed.Comment: 7 pages, 6 figure
Non-uniform convergence of two-photon decay rates for excited atomic states
Two-photon decay rates in simple atoms such as hydrogenlike systems represent
rather interesting fundamental problems in atomic physics. The sum of the
energies of the two emitted photons has to fulfill an energy conservation
condition, the decay takes place via intermediate virtual states, and the total
decay rate is obtained after an integration over the energy of one of the
emitted photons. Here, we investigate cases with a virtual state having an
energy intermediate between the initial and the final state of the decay
process, and we show that due to non-uniform convergence, only a careful
treatment of the singularities infinitesimally displaced from the photon
integration contour leads to consistent and convergent results.Comment: 3 pages; LaTe
Automorphisms of Partially Commutative Groups II: Combinatorial Subgroups
We define several "standard" subgroups of the automorphism group Aut(G) of a
partially commutative (right-angled Artin) group and use these standard
subgroups to describe decompositions of Aut(G). If C is the commutation graph
of G, we show how Aut(G) decomposes in terms of the connected components of C:
obtaining a particularly clear decomposition theorem in the special case where
C has no isolated vertices.
If C has no vertices of a type we call dominated then we give a semi-direct
decompostion of Aut(G) into a subgroup of locally conjugating automorphisms by
the subgroup stabilising a certain lattice of "admissible subsets" of the
vertices of C. We then characterise those graphs for which Aut(G) is a product
(not necessarily semi-direct) of two such subgroups.Comment: 7 figures, 63 pages. Notation and definitions clarified and typos
corrected. 2 new figures added. Appendix containing details of presentation
and proof of a theorem adde
Inside Money, Procyclical Leverage, and Banking Catastrophes
We explore a model of the interaction between banks and outside investors in
which the ability of banks to issue inside money (short-term liabilities
believed to be convertible into currency at par) can generate a collapse in
asset prices and widespread bank insolvency. The banks and investors share a
common belief about the future value of certain long-term assets, but they have
different objective functions; changes to this common belief result in
portfolio adjustments and trade. Positive belief shocks induce banks to buy
risky assets from investors, and the banks finance those purchases by issuing
new short-term liabilities. Negative belief shocks induce banks to sell assets
in order to reduce their chance of insolvency to a tolerably low level, and
they supply more assets at lower prices, which can result in multiple
market-clearing prices. A sufficiently severe negative shock causes the set of
equilibrium prices to contract (in a manner given by a cusp catastrophe),
causing prices to plummet discontinuously and banks to become insolvent.
Successive positive and negative shocks of equal magnitude do not cancel;
rather, a banking catastrophe can occur even if beliefs simply return to their
initial state. Capital requirements can prevent crises by curtailing the
expansion of balance sheets when beliefs become more optimistic, but they can
also force larger price declines. Emergency asset price supports can be
understood as attempts by a central bank to coordinate expectations on an
equilibrium with solvency.Comment: 31 pages, 10 figure
Chemistry on the inside: green chemistry in mesoporous materials
An overview of the rapidly expanding area of tailored mesoporous solids is presented. The synthesis of a wide range of the materials is covered, both inorganically and organically modified. Their applications, in particular those relating to green chemistry, are also highlighted. Finally, potential future directions for these materials are discussed
The Populations of Comet-Like Bodies in the Solar system
A new classification scheme is introduced for comet-like bodies in the Solar
system. It covers the traditional comets as well as the Centaurs and
Edgeworth-Kuiper belt objects. At low inclinations, close encounters with
planets often result in near-constant perihelion or aphelion distances, or in
perihelion-aphelion interchanges, so the minor bodies can be labelled according
to the planets predominantly controlling them at perihelion and aphelion. For
example, a JN object has a perihelion under the control of Jupiter and aphelion
under the control of Neptune, and so on. This provides 20 dynamically distinct
categories of outer Solar system objects in the Jovian and trans-Jovian
regions. The Tisserand parameter with respect to the planet controlling
perihelion is also often roughly constant under orbital evolution. So, each
category can be further sub-divided according to the Tisserand parameter. The
dynamical evolution of comets, however, is dominated not by the planets nearest
at perihelion or aphelion, but by the more massive Jupiter. The comets are
separated into four categories -- Encke-type, short-period, intermediate and
long-period -- according to aphelion distance. The Tisserand parameter
categories now roughly correspond to the well-known Jupiter-family comets,
transition-types and Halley-types. In this way, the nomenclature for the
Centaurs and Edgeworth-Kuiper belt objects is based on, and consistent with,
that for comets.Comment: MNRAS, in press, 11 pages, 6 figures (1 available as postscript, 5 as
gif). Higher resolution figures available at
http://www-thphys.physics.ox.ac.uk/users/WynEvans/preprints.pd
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