373 research outputs found
Intra-sexual competition alters the relationship between testosterone and ornament expression in a wild territorial bird
Open Access funded by Natural Environment Research Council Under a Creative Commons licensePeer reviewedPublisher PD
Urban agriculture: a global analysis of the space constraint to meet urban vegetable demand
Urban agriculture (UA) has been drawing a lot of attention recently for several reasons: the majority of the world population has shifted from living in rural to urban areas; the environmental impact of agriculture is a matter of rising concern; and food insecurity, especially the accessibility of food, remains a major challenge. UA has often been proposed as a solution to some of these issues, for example by producing food in places where population density is highest, reducing transportation costs, connecting people directly to food systems and using urban areas efficiently. However, to date no study has examined how much food could actually be produced in urban areas at the global scale. Here we use a simple approach, based on different global-scale datasets, to assess to what extent UA is constrained by the existing amount of urban space. Our results suggest that UA would require roughly one third of the total global urban area to meet the global vegetable consumption of urban dwellers. This estimate does not consider how much urban area may actually be suitable and available for UA, which likely varies substantially around the world and according to the type of UA performed. Further, this global average value masks variations of more than two orders of magnitude among individual countries. The variations in the space required across countries derive mostly from variations in urban population density, and much less from variations in yields or per capita consumption. Overall, the space required is regrettably the highest where UA is most needed, i.e., in more food insecure countries. We also show that smaller urban clusters (i.e., <100 km2 each) together represent about two thirds of the global urban extent; thus UA discourse and policies should not focus on large cities exclusively, but should also target smaller urban areas that offer the greatest potential in terms of physical space
Avian predators as a biological control system of common vole (Microtus arvalis) populations in NW Spain: experimental set-up and preliminary results
Jareño, D., Paz, A., Arroyo, L., Viñuela, J., Arroyo, B.E., Mougeot, F., Luque-Larena, J.J., Fargallo, J.A
Structure of unbound neutron-rich He studied using single-neutron transfer
The 8He(d,p) reaction was studied in inverse kinematics at 15.4A MeV using
the MUST2 Si-CsI array in order to shed light on the level structure of 9He.
The well known 16O(d,p)17O reaction, performed here in reverse kinematics, was
used as a test to validate the experimental methods. The 9He missing mass
spectrum was deduced from the kinetic energies and emission angles of the
recoiling protons. Several structures were observed above the neutron-emission
threshold and the angular distributions were used to deduce the multipolarity
of the transitions. This work confirms that the ground state of 9He is located
very close to the neutron threshold of 8He and supports the occurrence of
parity inversion in 9He.Comment: Exp\'erience GANIL/SPIRAL1/MUST
Urban agriculture, civil interfaces and moving beyond difference: the experiences of plot holders in Dublin and Belfast
Recent literature suggests that a âshared politics of placeâ attained through joint activities fosters social integration and provides people with a means to practise co-operation [Baumann, G., 1996. Contesting culture: discourses of identity in multi-ethnic London. Cambridge: Cambridge University Press; Sanjek, R., 1998. The future of us all: race & neighbourhood policies in New York City. Ithaca, NY: Cornell University Press; Sennett, R., 2012. Together: the rituals, pleasures and politics of cooperation. UK: Penguin]. Such a âshared politics of placeâ is most likely to occur in the context of public space conceptualised broadly as âthe setting for everyday spatial behaviour of individuals and communities, emphasizing ordinary activities of citizensâ [Lownsbrough, H. and Beunderman, J., 2007. Equally spaced? Public space and interaction between diverse communities. London: Demos, p. 8]. Here we explore one element of such public space â urban agriculture sites â with a view to identifying the extent to which a âshared politics of placeâ can be created and nurtured among the cultivating citizenry. The paper draws on data collected on allotment gardening sites in two urban contexts: Dublin (Ireland) and Belfast (Northern Ireland) over the period 2009â2013. We demonstrate the centrality of allotment cultivation to the generation of solidarity, mutuality and trust among participating citizens. Individuals engaging in allotment gardening in both Dublin and Belfast create and sustain civil interfaces â dismantling barriers, exchanging knowledge, challenging stereotypes, generating empathy and getting on with the business of simply getting on with their lives. The modus operandi of allotment gardening is predicated on a willingness to disregard social and ethno-national categorisations while on site. This is not to deny that such differences exist and persist, but allotments offer a âspace of potentialâ where those differences are, at least for a time, rendered less salient
Identification of genes responding to nematode infection in red grouse.
Abstract The identification of genes involved in a host's response to parasite infection provides both a means for understanding the pathways involved in immune defence and a target for examining host-parasite co-evolution. Most studies rely on a candidate gene approach derived from model systems to identify gene targets of interest, and there have been a dearth of studies geared towards providing a holistic overview of immune response from natural populations. We carried out an experiment in a natural population of red grouse (Lagopus lagopus scoticus) to manipulate levels of Trichostrongylus tenuis parasite infection. The transcriptomic response of individuals was examined from standard cDNA and suppressive subtractive hybridization (SSH) libraries produced from gut, liver and spleen, enriching for genes expressed in response to T. tenuis infection. A total of 2209 and 3716 unique transcript sequences were identified from the cDNA and SSH libraries, respectively. Forty-five of these had Gene Ontology annotation associated with immune response. Some of these genes have previously been reported from laboratory-based studies of model species as important in immune response to gastrointestinal parasite infection; however, multiple novel genes were also identified. These may reveal novel pathways involved in the host response of grouse to T. tenuis and provide a resource that can be utilized as candidate genes in other species
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Schantz et al., 1999) . Carotenoids can scavenge free radicals and cytotoxic molecules produced during immune respons
Isomeric excitation energy for In from mass spectrometry reveals constant trend next to doubly magic Sn
The excitation energy of the 1/2 isomer in In at is
measured to be 671(37) keV and the mass uncertainty of the 9/2 ground state
is significantly reduced using the ISOLTRAP mass spectrometer at ISOLDE/CERN.
The measurements exploit a major improvement in the resolution of the
multi-reflection time-of-flight mass spectrometer. The results reveal an
intriguing constancy of the isomer excitation energies in
neutron-deficient indium that persists down to the shell closure, even
when all neutrons are removed from the valence shell. This trend is used to
test large-scale shell model, \textit{ab initio}, and density functional theory
calculations. The models have difficulties describing both the isomer
excitation energies and ground-state electromagnetic moments along the indium
chain.Comment: 13 pages, 4 figure
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