2,190 research outputs found
Understanding the local livelihood system in reosurce management: the pelagic longline fishery in Gouyaye, Grenada
ABSTRACT There is a need to include social objectives in fisheries management, and this paper focuses on one set of social considerations, those regarding livelihood. We pay particular attention to sustainable livelihood strategies, the importance of commercial pelagic longline fishing for the entire community livelihood system, and implications for management. Field data were obtained between December 2002 and March 2004 in Gouyave, Grenada, using participant observation, semi-structured interviews, and a quantitative survey. The economic base (fishing and agriculture) of the community is both unpredictable and seasonal, therefore individuals and households engage in diverse strategies to secure their livelihood. Three livelihood strategies were deemed important: 1) livelihood diversification, developing additional sources of income from agriculture, wage labor, and trade work, 2) fishing diversification, learning to switch to alternative gear and species, and 3) the availability of an informal "social security net" involving cash and in-kind assistance. These strategies help to spread the flow of income and food during lean times and across seasons. A major management implication is that fishery managers need to pay attention to the multi-species nature of fisheries and to the importance of livelihood diversification, including reliance on other economic sectors. RESUMEN Existe la necesidad de incluir objetivos sociales en el manejo de la industria pesquera y este artículo se focaliza en un grupo de consideraciones sociales, las que se refieren al sustento. Prestanos particular atención a las estrategias de los sustento sostenibles, la importancia de la pesca pelágica comercial para el sustento de toda la comunida y las implicaciones para su manejo. Los datos de campo fueron obtenidos entre Diciembre del 2002 y Marzo del 2004 de Gouyave, Grenada a través del estudio de los participantes, entrevistas semi-estructuradas y un examen cuantitativo. La base económica (pesca y agricultura) de la comunidad es tanto impredecible como variable, por lo tanto individuos y hogares adoptan estrategias diversificadas para logar la seguridad del sustento. Tres estrategias de sustento fueron consideradas importantes: 1) diversificación de las actividades para sustento desarrollando fuentes de ingresos adicionales en agricultura, labor pagada y trabajo de obrero, 2) la diversificación de la pesca aprendiendo a utilizar hacia equipos y especies alternativas, y 3) la disponibilidad de una red de seguridad social que incluye asistencia monetaria y en especie. Estas estrategias diversificadas ayudan a distribuir el flujo de ingresos y alimentos a través de las estaciones. Un mayor involvcramiento en el manejo implica que los gerentes pesqueros presten mayor cuidado a la naturaleza multi-especies de la pesca y a la importancia de la diversificacion del sustento, incluyendo la confianza en otros sectores económicos
Fisheries Ecology: Hunger for Shark Fin Soup Drives Clam Chowder off the Menu
Removal by fishing of large sharks has reduced predation-pressure on shark prey and, via a trophic cascade, caused clam populations to crash. This indirect response illustrates why fisheries should be managed in a whole-ecosystem context
Brain GLP-1 and the regulation of food intake: GLP-1 action in the brain and its implications for GLP-1 receptor agonists in obesity treatment
This review considers the similarities and differences between the physiological systems regulated by gut-derived and neuronally-produced GLP-1. It addresses the questions of whether peripheral and central GLP-1 sources constitute separate, linked, or redundant systems, whether the brain GLP-1 system consists of disparate sections or is a homogenous entity, and it explores the implications of the answers to these questions for the use of GLP-1 receptor agonists as anti-obesity drugs
Moonlight drives ocean-scale mass vertical migration of zooplankton during the Arctic winter
The creation of the pan-Arctic archive of ADCP data was supported by the UK Natural Environment Research Council (NERC) (Panarchive: NE/H012524/1 and SOFI: NE/F012381/1) as was mooring work in Svalbard (Oceans 2025 and Northern Sea Program). Moorings were also supported by the Research Council of Norway (NFR) projects: Circa (214271), Cleopatra (178766), Cleopatra II (216537), and Marine Night (226471).In extreme high-latitude marine environments that are without solar illumination in winter, light-mediated patterns of biological migration have historically been considered non-existent [1]. However, diel vertical migration (DVM) of zooplankton has been shown to occur even during the darkest part of the polar night, when illumination levels are exceptionally low [2 and 3]. This paradox is, as yet, unexplained. Here, we present evidence of an unexpected uniform behavior across the entire Arctic, in fjord, shelf, slope and open sea, where vertical migrations of zooplankton are driven by lunar illumination. A shift from solar-day (24-hr period) to lunar-day (24.8-hr period) vertical migration takes place in winter when the moon rises above the horizon. Further, mass sinking of zooplankton from the surface waters and accumulation at a depth of ∼50 m occurs every 29.5 days in winter, coincident with the periods of full moon. Moonlight may enable predation of zooplankton by carnivorous zooplankters, fish, and birds now known to feed during the polar night [4]. Although primary production is almost nil at this time, lunar vertical migration (LVM) may facilitate monthly pulses of carbon remineralization, as they occur continuously in illuminated mesopelagic systems [5], due to community respiration of carnivorous and detritivorous zooplankton. The extent of LVM during the winter suggests that the behavior is highly conserved and adaptive and therefore needs to be considered as “baseline” zooplankton activity in a changing Arctic ocean [6, 7, 8 and 9].Publisher PDFPeer reviewe
On the Impossibility to Extend Triples of Mutually Unbiased Product Bases in Dimension Six
An analytic proof is given which shows that it is impossible to extend any
triple of mutually unbiased (MU) product bases in dimension six by a single MU
vector. Furthermore, the 16 states obtained by removing two orthogonal states
from any MU product triple cannot figure in a (hypothetical) complete set of
seven MU bases. These results follow from exploiting the structure of MU
product bases in a novel fashion, and they are among the strongest ones
obtained for MU bases in dimension six without recourse to computer algebra.Comment: 12 pages, identical to published versio
Studies on preform properties of multilayer interlocked woven structures using fabric geometrical factors
Structure property correlation is a critical textile research area explored by various researchers and many factors have been proposed over the years to
predict/compare/design the woven fabrics. Cross-over firmness factor (CFF) and floating yarn factor (FYF) have been recently proposed as parameters to
understand weave effect on fabric properties (Morino, H., Matsudaira, M. and Furutani, M. (2005). Predicting Mechanical Properties and Hand Values from the
Parameters of Weave Structures, Textile Research Journal, 75(3): 252—257). Redefined CFF and FYF factors using fabric fields in terms of interlacement
index (I) and float index (F), respectively have been proposed in this article. This new approach provides better understanding of the interlacements and floats
in the woven structure and further they are applied on multilayer interlocked fabrics to quantify the structural influence on the properties. Multilayer interlocked
woven fabrics with different interlacement patterns have been developed. Influence of fabric structure on preform properties relevant for resin transfer molding
composite manufacture, such as compression, permeability, and tensile behavior were studied with respect to the interlacement and float indices. Tensile and
compression tests were conducted on universal testing machine. Liquid permeability of these structures was evaluated based on horizontal wicking and contact
angle wettability tests. Results show that influence of structural factor is greater on tensile and permeability properties than the compression properties of these
multilayer fabricsThis work has been conducted within the Asia-Link Programme RPO1736, project no IN/ASIA-LINK/002 (82158). The authors wish to thank the European Commission for awarding research programme under the EU Asia-link project to the University of Minho (Portugal) and Indian Institute of Technology-Delhi (New Delhi, India)
Effects of Earth system feedbacks on the potential mitigation of large-scale tropical forest restoration
To achieve the Paris Agreement requires aggressive mitigation strategies alongside negative emission technologies. Recent studies suggest that increasing tree cover can make a substantial contribution to negative emissions, with the tropics being the most suitable region from a biogeophysical perspective. Yet these studies typically do not account for subsequent carbon cycle and climate responses to large-scale land-use change. Here we quantify the maximum potential temperature and CO2 benefits from pantropical forest restoration, including the Earth system response, using a fully coupled, emission-driven Earth system model (HadGEM2-ES). We perform an idealised experiment where all land use in the tropics is stopped and vegetation is allowed to recover, on top of an aggressive mitigation scenario (RCP2.6). We find that tropical restoration of 1529 Mha increases carbon stored in live biomass by 130 Pg C by 2100 CE. Whilst avoiding deforestation and tropical restoration in the tropics removes 42 Pg C compared to RCP2.6, the subsequent reduction in extratropical and ocean carbon uptake means that carbon in the atmosphere only reduces by 18 Pg C by 2100. The resulting small CO2 (9 ppm) benefit does not translate to a detectable reduction in global surface air temperature compared to the control experiment. The greatest carbon benefit is achieved 30–50 years after restoration before the Earth system response adjusts to the new land-use regime and declining fossil fuel use. Comparing our results with previous modelling studies, we identify two model-independent key points: (i) in a world where emission reductions follow the Paris Agreement, restoration is best deployed immediately, and (ii) the global carbon cycle response to reduced emissions limits the efficacy of negative emissions technologies by more than half. We conclude that forest restoration can reduce peak CO2 mid-century, but it can only modestly contribute to negative emissions
The spiritual revolution and suicidal ideation: an empirical enquiry among 13- to 15-year-old adolescents in England and Wales
The association between conventional religiosity and suicide inhibition has been well explored and documented since the pioneering work of Durkheim. Commentators like Heelas and Woodhead point to ways in which conventional religiosity is giving way in England and Wales to a range of alternative spiritualities, including renewed interest in paranormal phenomena. Taking a sample of 3095 13- to 15-year-old adolescents, the present study examines the association between suicidal ideation and both conventional religiosity and paranormal beliefs, after controlling for individual differences in sex, age and personality (extraversion, neuroticism and psychoticism). The data demonstrate that, while conventional religiosity is slightly associated with lower levels of suicidal ideation, paranormal beliefs are strongly associated with higher levels of suicidal ideation
The Limited Role of Mutually Unbiased Product Bases in Dimension Six
We show that a complete set of seven mutually unbiased bases in dimension
six, if it exists, cannot contain more than one product basis.Comment: 8 pages, identical to published versio
New class of quantum error-correcting codes for a bosonic mode
We construct a new class of quantum error-correcting codes for a bosonic mode
which are advantageous for applications in quantum memories, communication, and
scalable computation. These 'binomial quantum codes' are formed from a finite
superposition of Fock states weighted with binomial coefficients. The binomial
codes can exactly correct errors that are polynomial up to a specific degree in
bosonic creation and annihilation operators, including amplitude damping and
displacement noise as well as boson addition and dephasing errors. For
realistic continuous-time dissipative evolution, the codes can perform
approximate quantum error correction to any given order in the timestep between
error detection measurements. We present an explicit approximate quantum error
recovery operation based on projective measurements and unitary operations. The
binomial codes are tailored for detecting boson loss and gain errors by means
of measurements of the generalized number parity. We discuss optimization of
the binomial codes and demonstrate that by relaxing the parity structure, codes
with even lower unrecoverable error rates can be achieved. The binomial codes
are related to existing two-mode bosonic codes but offer the advantage of
requiring only a single bosonic mode to correct amplitude damping as well as
the ability to correct other errors. Our codes are similar in spirit to 'cat
codes' based on superpositions of the coherent states, but offer several
advantages such as smaller mean number, exact rather than approximate
orthonormality of the code words, and an explicit unitary operation for
repumping energy into the bosonic mode. The binomial quantum codes are
realizable with current superconducting circuit technology and they should
prove useful in other quantum technologies, including bosonic quantum memories,
photonic quantum communication, and optical-to-microwave up- and
down-conversion.Comment: Published versio
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