Summer Sea Ice Concentration, Motion, and Thickness Near Areas of Proposed Offshore Oil and Gas Development in the Canadian Beaufort Sea – 2009

This study was motivated by the potential development of offshore oil exploration leases in the Canadian Southern Beaufort Sea, an area within the Inuvialuit Settlement Region. Sea ice concentration, extent, motion, and thickness data are vital to the success of potential oil operations in this region, and relevant data cannot be gleaned from larger-scale hemispheric studies. We therefore undertook regionally specific sea ice analyses in the southern Beaufort Sea during the summer drilling season (July, August, and September) in 2009 and over the long-term (1996 – 2010). On average, the Canadian oil lease areas contain mostly old sea ice during the drilling season and have not experienced significant decreasing trends in total or old sea ice. The average sea ice motion in the region for the period was anti-cyclonic at 20 – 25 cm·s-1, acting to transport sea ice southward toward the lease areas. Summer 2009 was used as a case study of regional ice concentration, motion, and thickness and to compare September sea ice thickness measurements to data collected in April 2009. In the summer of 2009, old sea ice was the predominant ice type in the lease areas. Sea ice motion was anti-cyclonic and faster than the long-term average, reaching 60 cm·s-1 west of Banks Island and across the north end of the lease areas. September 2009 sea ice thickness (mean = 1.03 m, σ = 0.97 m) was modal about the 0.20 – 0.29 m thickness bin. The sea ice thickness distri­bution was spatially variable, with the thickest ice occurring at the north end of the study area, in an area dominated by high old ice concentrations. Ice thicknesses greater than 10 m (the upper limit our instruments could measure) were encountered. Thinner sea ice predominated at the periphery of the core Beaufort Sea multi-year pack. Near the oil lease areas, the sea ice thickness distributions were shifted left on the histogram in comparison to those farther north, resulting in a greater proportion of relatively thick sea ice due to the thermodynamic loss of thinner (< 1.5 m) first-year ice during its southward movement. After enduring a summer’s melt, however, this thicker ice at the south end of the study region had thinned in comparison to the ice at the north end.La présente étude a été motivée par la mise en valeur potentielle des concessions d’exploration pétrolière au large de la mer de Beaufort, dans la partie sud canadienne, un endroit qui fait partie de la région désignée des Inuvialuit. Les données relatives à la concentration, à l’étendue, au déplacement et à l’épaisseur de la glace de mer sont essentielles à la réussite de l’exploitation éventuelle du pétrole dans cette région, et les données pertinentes ne peuvent être dépouillées à partir d’études hémisphériques réalisées à grande échelle. Par conséquent, nous avons entrepris de faire des analyses particulièrement régionales de la glace de mer du sud de la mer de Beaufort pendant la saison de forage d’été (juillet, août et septembre) en 2009 de même que sur une plus longue période (1996-2010). En moyenne, les régions visées par les concessions pétrolières canadiennes renferment principalement de la vieille glace de mer pendant la saison de forage, et elles n’enregistrent pas d’importantes tendances à la baisse sur le plan de l’ensemble de la glace de mer ou de la vieille glace de mer. Dans la région, le déplacement moyen de la glace de mer pendant la période était anticyclonique à 20 25 cm·s-1, ce qui avait pour effet de transporter la glace de mer vers le sud et vers les concessions. L’été 2009 nous a servi d’étude de cas en matière de concentration, de déplacement et d’épaisseur de la glace régionale, et nous a permis de comparer les mesures de l’épaisseur de la glace de mer de septembre aux données recueillies en avril 2009. À l’été 2009, la vieille glace de mer représentait le type de glace prédominant dans les concessions. Le déplacement de la glace de mer était anticyclonique et se faisait plus vite que la moyenne à long terme, atteignant ainsi 60 cm·s-1 à l’ouest de l’île Banks et à la hauteur du nord de la zone de concessions. En septembre 2009, l’épaisseur de la glace de mer (moyenne = 1,03 m, σ = 0,97 m) était modale à la hauteur de la classe de l’épaisseur 0,20 – 0,29 m. La répartition de l’épaisseur de la glace de mer variait en fonction de l’emplacement, la glace la plus épaisse se trouvant du côté nord de la région étudiée, dans une zone dominée par de fortes concentrations de vieille glace. La glace atteignait des épaisseurs de plus de 10 m (la limite maximale que nos instruments pouvaient mesurer) par endroits. Une glace de mer plus mince prédominait la périphérie du noyau de la banquise pluriannuelle de la mer de Beaufort. Près de la zone de concessions pétrolières, les répartitions d’épaisseurs de glace de mer se sont déplacées vers la gauche sur l’histogramme comparativement à celles plus au nord, ce qui a donné une plus grande proportion de glace de mer relativement épaisse en raison de la perte thermodynamique de la glace plus mince de première année (< 1,5 m) pendant son déplacement vers le sud. Cependant, après avoir enduré la fonte d’un été, la glace plus épaisse du côté sud de la région à l’étude s’était amincie compara­tivement à la glace se trouvant du côté nord

Visual Interest Prediction with Attentive Multi-Task Transfer Learning

Visual interest & affect prediction is a very interesting area of research in the area of computer vision. In this paper, we propose a transfer learning and attention mechanism based neural network model to predict visual interest & affective dimensions in digital photos. Learning the multi-dimensional affects is addressed through a multi-task learning framework. With various experiments we show the effectiveness of the proposed approach. Evaluation of our model on the benchmark dataset shows large improvement over current state-of-the-art systems

Beyond transformations: Zooming in on agricultural digitalization and the changing social practices of rural farming in Northern Ghana, West Africa

Digitalization of agriculture (DA) has emerged as a powerful rural transformative force. However, the dynamics of how digitalization is changing smallholder farming practices at the heart of rural life remain underexplored. Here, we employ a mixed-method approach (1565 survey respondents, 16 focus group discussions, and 22 interviews) to examine farmers' experiences with digital agriculture services in Northern Ghana through a social practice theory (SPT) lens. We found that farmers perceive digitalization as transitioning their everyday activities across the farming spectrum, including decisions and activities related to season planning, planting, husbandry, harvesting, post-harvest management, and sales. Notably, 1) new materials of phones and digital platforms redefine farmers’ knowledge and competencies, ultimately 2) temporary re-patterning their routines and rhythms. Therefore, we argue that, beyond the contested claims of digital transformations, a pertinent dimension of DA and rural social change is the transitions in the everyday practices of farmers and rural living. Our paper, as we know, is among the early attempts to theoretically and empirically examine agriculture digitalization through an explicit practice lens, and more so in the context of African smallholder systems. We contribute to the scholarship on DA and rural change by (re)framing the dynamics of the phenomenon through everyday practices. By this approach we aim to steer the DA discourse and policy from the optimistic rural transformations towards the often-overlooked yet critical gradual changes and transitions in the day-to-day life of farmers

Blood parasites in endangered wildlife - Trypanosomes discovered during a survey of haemoprotozoa from the Tasmanian devil

The impact of emerging infectious diseases is increasingly recognised as a major threat to wildlife. Wild populations of the endangered Tasmanian devil, Sarcophilus harrisii, are experiencing devastating losses from a novel transmissible cancer, devil facial tumour disease (DFTD); however, despite the rapid decline of this species, there is currently no information on the presence of haemoprotozoan parasites. In the present study, 95 Tasmanian devil blood samples were collected from four populations in Tasmania, Australia, which underwent molecular screening to detect four major groups of haemoprotozoa: (i) trypanosomes, (ii) piroplasms, (iii) Hepatozoon, and (iv) haemosporidia. Sequence results revealed Trypanosoma infections in 32/95 individuals. Trypanosoma copemani was identified in 10 Tasmanian devils from three sites and a second Trypanosoma sp. was identified in 22 individuals that were grouped within the poorly described T. cyclops clade. A single blood sample was positive for Babesia sp., which most closely matched Babesia lohae. No other blood protozoan parasite DNA was detected. This study provides the first insight into haemoprotozoa from the Tasmanian devil and the first identification of Trypanosoma and Babesia in this carnivorous marsupial

Wildland fire in ecosystems: Effects of fire on soil and water

This state-of-knowledge review about the effects of fire on soils and water can assist land and fire managers with information on the physical, chemical, and biological effects of fire needed to successfully conduct ecosystem management, and effectively inform others about the role and impacts of wildland fire. Chapter topics include the soil resource, soil physical properties and fire, soil chemistry effects, soil biology responses, the hydrologic cycle and water resources, water quality, aquatic biology, fire effectson wetland and riparian systems, fire effects models, and watershed rehabilitation

Milagrito: a TeV air-shower array

Milagrito, a large, covered water-Cherenkov detector, was the world's first air-shower-particle detector sensitive to cosmic gamma rays below 1 TeV. It served as a prototype for the Milagro detector and operated from February 1997 to May 1998. This paper gives a description of Milagrito, a summary of the operating experience, and early results that demonstrate the capabilities of this technique.Comment: 38 pages including 24 figure

Nucleosynthesis Constraints on a Massive Gravitino in Neutralino Dark Matter Scenarios

The decays of massive gravitinos into neutralino dark matter particles and Standard Model secondaries during or after Big-Bang nucleosynthesis (BBN) may alter the primordial light-element abundances. We present here details of a new suite of codes for evaluating such effects, including a new treatment based on PYTHIA of the evolution of showers induced by hadronic decays of massive, unstable particles such as a gravitino. We also develop an analytical treatment of non-thermal hadron propagation in the early universe, and use this to derive analytical estimates for light-element production and in turn on decaying particle lifetimes and abundances. We then consider specifically the case of an unstable massive gravitino within the constrained minimal supersymmetric extension of the Standard Model (CMSSM). We present upper limits on its possible primordial abundance before decay for different possible gravitino masses, with CMSSM parameters along strips where the lightest neutralino provides all the astrophysical cold dark matter density. We do not find any CMSSM solution to the cosmological Li7 problem for small m_{3/2}. Discounting this, for m_{1/2} ~ 500 GeV and tan beta = 10 the other light-element abundances impose an upper limit m_{3/2} n_{3/2}/n_\gamma < 3 \times 10^{-12} GeV to < 2 \times 10^{-13} GeV for m_{3/2} = 250 GeV to 1 TeV, which is similar in both the coannihilation and focus-point strips and somewhat weaker for tan beta = 50, particularly for larger m_{1/2}. The constraints also weaken in general for larger m_{3/2}, and for m_{3/2} > 3 TeV we find a narrow range of m_{3/2} n_{3/2}/n_\gamma, at values which increase with m_{3/2}, where the Li7 abundance is marginally compatible with the other light-element abundances.Comment: 74 pages, 40 Figure

Time-of-flight and activation experiments on 147Pm and 171Tm for astrophysics

The neutron capture cross section of several key unstable isotopes acting as branching points in the s-process are crucial for stellar nucleosynthesis studies, but they are very challenging to measure due to the difficult production of sufficient sample material, the high activity of the resulting samples, and the actual (n,γ) measurement, for which high neutron fluxes and effective background rejection capabilities are required. As part of a new program to measure some of these important branching points, radioactive targets of 147Pm and 171Tm have been produced by irradiation of stable isotopes at the ILL high flux reactor. Neutron capture on 146Nd and 170Er at the reactor was followed by beta decay and the resulting matrix was purified via radiochemical separation at PSI. The radioactive targets have been used for time-of-flight measurements at the CERN n-TOF facility using the 19 and 185 m beam lines during 2014 and 2015. The capture cascades were detected using a set of four C6D6 scintillators, allowing to observe the associated neutron capture resonances. The results presented in this work are the first ever determination of the resonance capture cross section of 147Pm and 171Tm. Activation experiments on the same 147Pm and 171Tm targets with a high-intensity 30 keV quasi-Maxwellian flux of neutrons will be performed using the SARAF accelerator and the Liquid-Lithium Target (LiLiT) in order to extract the corresponding Maxwellian Average Cross Section (MACS). The status of these experiments and preliminary results will be presented and discussed as well

Characterization of the n-TOF EAR-2 neutron beam

The experimental area 2 (EAR-2) at CERNs neutron time-of-flight facility (n-TOF), which is operational since 2014, is designed and built as a short-distance complement to the experimental area 1 (EAR-1). The Parallel Plate Avalanche Counter (PPAC) monitor experiment was performed to characterize the beam prole and the shape of the neutron 'ux at EAR-2. The prompt γ-flash which is used for calibrating the time-of-flight at EAR-1 is not seen by PPAC at EAR-2, shedding light on the physical origin of this γ-flash

Measurement of the 240Pu(n,f) cross-section at the CERN n-TOF facility : First results from experimental area II (EAR-2)

The accurate knowledge of the neutron-induced fission cross-sections of actinides and other isotopes involved in the nuclear fuel cycle is essential for the design of advanced nuclear systems, such as Generation-IV nuclear reactors. Such experimental data can also provide the necessary feedback for the adjustment of nuclear model parameters used in the evaluation process, resulting in the further development of nuclear fission models. In the present work, the 240Pu(n,f) cross-section was measured at CERN's n-TOF facility relative to the well-known 235U(n,f) cross section, over a wide range of neutron energies, from meV to almost MeV, using the time-of-flight technique and a set-up based on Micromegas detectors. This measurement was the first experiment to be performed at n-TOF's new experimental area (EAR-2), which offers a significantly higher neutron flux compared to the already existing experimental area (EAR-1). Preliminary results as well as the experimental procedure, including a description of the facility and the data handling and analysis, are presented