Industrial Aquaculture: History, Problems, Potential - Political Economic Review and Analysis of Socioecological Issues in Global Industrial Aquaculture Supply Chains

*This report highlights characteristics of global industrial aquaculture value chains. For example: Most producers are located in global South countries, but rely on input (e.g. feed, pest control agents) that are often in the hands of wealthy corporations in the EU and U.S. Global supply chains are buyer-driven, with massive grocery and retail food conglomerates based in the global North being the most powerful buyers. *Several key concerns related to feed are emphasized. For example: Social concerns of worker exploitation and forced labor to capture wild fish to feed farmed fish. Marine ecological concerns as wild fish stock suffers as a result of pressures to obtain "trash fish" as aquafeed. Concerns with impacts on terrestrial environment such as cutting down forests to cultivate soybean to feed farmed fish.*The prevalence of pests and diseases and the heavy use of antibiotics in industrial aquaculture operations is another concern. Intensive aquaculture also raises ethical concerns with regard to the welfare of the farmed aquatic animals.*The "displacement paradox" and the "Jevons paradox" in industrial aquaculture is explained.*The report cautions against the use of regulations that emphasize market mechanisms and new technologies as key solutions to industrial aquaculture with global value chains. It recommends instead the promotion of small-scale local supply chains, the production of species that are less reliant on intensive inputs, more in-tune with their ecological surroundings, and lower on the food chain (e.g. mussels, oysters)

Metabolic Rifts and Restoration: Agricultural Crises and the Potential of Cuba's Organic, Socialist Approach to Food Production

We employ Karl Marx's metabolic approach—via the concepts of metabolic rift and metabolic restoration—to study the dynamic relationships of interchange associated with distinct agricultural systems. First, we offer an assessment of contemporary capitalist agriculture, including organic agriculture in the United States. We address how the organization of capitalist agriculture inherently generates ecological problems and metabolic rifts in the soil nutrient cycle. Second, we discuss the promise for a socially and ecologically just food system. We examine Cuba's model of organic agriculture, highlighting the potential for metabolic restoration

The Role Of Distinction In Dialectical Analyses Of Socioecology: Metabolic Rift, World Ecology, And Urban Political Ecology

The concept of metabolism, as applied to the interrelations between human society and the rest of nature, has been one of the most fruitful iterations of socioecological thought over the last few decades. Here we will examine specific orientations of metabolic thought commonly employed in the social sciences, and their depiction of metabolism as it relates to the “society–nature” problematic and elaborate on the role of the dialectical method when analyzing socioecological processes and distinctions between society and the rest of nature. We will review two overarching uses of metabolism: the theory of metabolic rift and a hybridist metabolic approach to socio-nature. While the former regards society as an emergent property of nature, the latter regards distinctions between the two as undialectical and dualist. First, we review each of these approaches and how they differ in their application of the dialectical method. Then we explore some of the analytic implications of these differing approaches. We contend that a dialectical method that allows for, and encourages, analytical distinction is essential, and that the metabolic rift theory provides an important potential for advancing socioecological analysis in an era of anthropogenic environmental change through its use of analytical distinction between social and environmental phenomena

Response to comment on 'Amphibian fungal panzootic causes catastrophic and ongoing loss of biodiversity'

Lambert et al. question our retrospective and holistic epidemiological assessment of the role of chytridiomycosis in amphibian declines. Their alternative assessment is narrow and provides an incomplete evaluation of evidence. Adopting this approach limits understanding of infectious disease impacts and hampers conservation efforts. We reaffirm that our study provides unambiguous evidence that chytridiomycosis has affected at least 501 amphibian species

Multiplicities of charged pions and unidentified charged hadrons from deep-inelastic scattering of muons off an isoscalar target

Multiplicities of charged pions and unidentified hadrons produced in deep-inelastic scattering were measured in bins of the Bjorken scaling variable $x$, the relative virtual-photon energy $y$ and the relative hadron energy $z$. Data were obtained by the COMPASS Collaboration using a 160 GeV muon beam and an isoscalar target ($^6$LiD). They cover the kinematic domain in the photon virtuality $Q^2$ > 1(GeV/c$)^2$, $0.004 < x < 0.4$, $0.2 < z < 0.85$ and $0.1 < y < 0.7$. In addition, a leading-order pQCD analysis was performed using the pion multiplicity results to extract quark fragmentation functions

A population of gamma-ray emitting globular clusters seen with the Fermi Large Area Telescope

Globular clusters with their large populations of millisecond pulsars (MSPs) are believed to be potential emitters of high-energy gamma-ray emission. Our goal is to constrain the millisecond pulsar populations in globular clusters from analysis of gamma-ray observations. We use 546 days of continuous sky-survey observations obtained with the Large Area Telescope aboard the Fermi Gamma-ray Space Telescope to study the gamma-ray emission towards 13 globular clusters. Steady point-like high-energy gamma-ray emission has been significantly detected towards 8 globular clusters. Five of them (47 Tucanae, Omega Cen, NGC 6388, Terzan 5, and M 28) show hard spectral power indices $(0.7 < \Gamma <1.4)$ and clear evidence for an exponential cut-off in the range 1.0-2.6 GeV, which is the characteristic signature of magnetospheric emission from MSPs. Three of them (M 62, NGC 6440 and NGC 6652) also show hard spectral indices $(1.0 < \Gamma < 1.7)$, however the presence of an exponential cut-off can not be unambiguously established. Three of them (Omega Cen, NGC 6388, NGC 6652) have no known radio or X-ray MSPs yet still exhibit MSP spectral properties. From the observed gamma-ray luminosities, we estimate the total number of MSPs that is expected to be present in these globular clusters. We show that our estimates of the MSP population correlate with the stellar encounter rate and we estimate 2600-4700 MSPs in Galactic globular clusters, commensurate with previous estimates. The observation of high-energy gamma-ray emission from a globular cluster thus provides a reliable independent method to assess their millisecond pulsar populations that can be used to make constraints on the original neutron star X-ray binary population, essential for understanding the importance of binary systems in slowing the inevitable core collapse of globular clusters.Comment: Accepted for publication in A&A. Corresponding authors: J. Kn\"odlseder, N. Webb, B. Pancraz

Fermi Large Area Telescope Constraints on the Gamma-ray Opacity of the Universe

The Extragalactic Background Light (EBL) includes photons with wavelengths from ultraviolet to infrared, which are effective at attenuating gamma rays with energy above ~10 GeV during propagation from sources at cosmological distances. This results in a redshift- and energy-dependent attenuation of the gamma-ray flux of extragalactic sources such as blazars and Gamma-Ray Bursts (GRBs). The Large Area Telescope onboard Fermi detects a sample of gamma-ray blazars with redshift up to z~3, and GRBs with redshift up to z~4.3. Using photons above 10 GeV collected by Fermi over more than one year of observations for these sources, we investigate the effect of gamma-ray flux attenuation by the EBL. We place upper limits on the gamma-ray opacity of the Universe at various energies and redshifts, and compare this with predictions from well-known EBL models. We find that an EBL intensity in the optical-ultraviolet wavelengths as great as predicted by the "baseline" model of Stecker et al. (2006) can be ruled out with high confidence.Comment: 42 pages, 12 figures, accepted version (24 Aug.2010) for publication in ApJ; Contact authors: A. Bouvier, A. Chen, S. Raino, S. Razzaque, A. Reimer, L.C. Reye

Original Article

The pancreas taken from the frog (Rana nigromaculata) was fixed in 1% OsO_4 and sliced into ultrathin sections for electron microscopic studies. The following observations were made: 1. A great \u27number of minute granules found in the cytoplasm of a pancreatic cell were called the microsomes, which were divided into two types, the C-microsome and S-microsome. 2. Electron microsopic studies of the ergastoplasm showed that it is composed of the microsome granules and A-substance. The microsomes were seen embedded in the A-substance which was either filamentous or membranous. The membranous structure, which was called the Am-membrane, was seen to form a sac, with a cavity of varying sizes, or to form a lamella. 3. The Am-membrane has close similarity to α-cytomembrane of Sjostrand, except that the latter is rough-surfaced. It was deduced that the Am-membrane, which is smooth-surfaced, might turn into the rough-surfaced α-cytomembrane. 4. There was the Golgi apparatus in the supranuclear region of a pancreatic cell. It consisted of the Golgi membrane, Golgi vacuole and. Golgi vesicle. 5. The mitochondria of a pancreatic cell appeared like long filaments, and some of them were seen to ramify. 6. The membrane of mitochondria, i. e. the limiting membrane, consisted of the Ammembrane. The mitochondria contained a lot of A-substances, as well as the C-microsomes and S-microsomes. When the mitochondria came into being, there appeared inside them chains of granules, which appeared like strips of beads, as the outgrowths of the A-substance and the microsome granules attached to the Am-membrane. They are the so-called cristae mitochondriales. 7. The secretory granules originate in the microsomes. They came into being when the microsomes gradually thickened and grew in size as various substances became adhered to them. Some of the secretory granules were covered with a membrane and appeared like what they have called the intracisternal granule of Palade.It seemed that this was a phenomenon attendant upon the dissolution and liqutefaction of the secretory granule. 8. Comparative studies were made of the ergastoplasm of the pancreatic cells from the frogs in hibernation, the frogs artificially hungered, the frogs which were given food after a certain period of fasting, the frogs to which pilocarpine was given subcutaneously, and the very young, immature frogs. The studies revealed that the ergastoplasm of the pancreatic cells greatly varied in form with the difference in nutritive condition and with different developmental stages of the cell. The change in form and structure occured as a result of transformation of the microsomes and A-substance. The ergastoplasm, even after it has come into being, might easily be inactivated if nutrition is defective. The ergastoplasm is concerned in the secretory mechanism, which is different from the secretory phenomenon of the secretory granules. It would seem that structurally the mitochondria have no direct relation to this mechanism

The liquid-argon scintillation pulseshape in DEAP-3600

DEAP-3600 is a liquid-argon scintillation detector looking for dark matter. Scintillation events in the liquid argon (LAr) are registered by 255 photomultiplier tubes (PMTs), and pulseshape discrimination (PSD) is used to suppress electromagnetic background events. The excellent PSD performance of LAr makes it a viable target for dark matter searches, and the LAr scintillation pulseshape discussed here is the basis of PSD. The observed pulseshape is a combination of LAr scintillation physics with detector effects. We present a model for the pulseshape of electromagnetic background events in the energy region of interest for dark matter searches. The model is composed of (a) LAr scintillation physics, including the so-called intermediate component, (b) the time response of the TPB wavelength shifter, including delayed TPB emission at O(ms) time-scales, and c) PMT response. TPB is the wavelength shifter of choice in most LAr detectors. We find that approximately 10% of the intensity of the wavelength-shifted light is in a long-lived state of TPB. This causes light from an event to spill into subsequent events to an extent not usually accounted for in the design and data analysis of LAr-based detectors