Prepontine non-giant neurons drive flexible escape behavior in zebrafish

Many species execute ballistic escape reactions to avoid imminent danger. Despite fast reaction times, responses are often highly regulated, reflecting a trade-off between costly motor actions and perceived threat level. However, how sensory cues are integrated within premotor escape circuits remains poorly understood. Here, we show that in zebrafish, less precipitous threats elicit a delayed escape, characterized by flexible trajectories, which are driven by a cluster of 38 prepontine neurons that are completely separate from the fast escape pathway. Whereas neurons that initiate rapid escapes receive direct auditory input and drive motor neurons, input and output pathways for delayed escapes are indirect, facilitating integration of cross-modal sensory information. These results show that rapid decision-making in the escape system is enabled by parallel pathways for ballistic responses and flexible delayed actions and defines a neuronal substrate for hierarchical choice in the vertebrate nervous system

Skylab investigation of the upwelling off the Northwest coast of Africa

The upwelling off the NW coast of Africa in the vicinity of Cape Blanc was studied in February - March 1974 from aircraft and in September 1973 from Skylab. The aircraft study was designed to determine the effectiveness of a differential radiometer in quantifying surface chlorophyll concentrations. Photographic images of the S190A Multispectral Camera and the S190B Earth Terrain Camera from Skylab were used to study distributional patterns of suspended material and to locate ocean color boundaries. The thermal channel of the S192 Multispectral Scanner was used to map sea-surface temperature distributions offshore of Cape Blanc. Correlating ocean color changes with temperature gradients is an effective method of qualitatively estimating biological productivity in the upwelling region off Africa

Lessons learned from professional development workshops on using GIS to teach geography and history in the K-12 classroom

A GIS oriented professional development activity engaged social studies teachers with the importance of maps and graphics in teaching geography and history. With an introduction to ArcGIS Online and National Geographic Map Maker, the activity provided teachers with the ability to make their own maps and identify GIS materials for their classrooms. Conducting the workshop reinforced our belief in the need for considerable hands-on activity with participants allowed to work at their own pace. Pre- and post-event surveys showed positive gains regarding the teachers’ likelihood to include GIS based maps and graphics in teaching. The activity provided teachers with enough knowledge of GIS that they were ready to use the technology immediately

The role of quantum fluctuations in the optomechanical properties of a Bose-Einstein condensate in a ring cavity

We analyze a detailed model of a Bose-Einstein condensate trapped in a ring optical resonator and contrast its classical and quantum properties to those of a Fabry-P{\'e}rot geometry. The inclusion of two counter-propagating light fields and three matter field modes leads to important differences between the two situations. Specifically, we identify an experimentally realizable region where the system's behavior differs strongly from that of a BEC in a Fabry-P\'{e}rot cavity, and also where quantum corrections become significant. The classical dynamics are rich, and near bifurcation points in the mean-field classical system, the quantum fluctuations have a major impact on the system's dynamics.Comment: 11 pages, 11 figures, submitted to PR

On vacuum gravitational collapse in nine dimensions

We consider the vacuum gravitational collapse for cohomogeneity-two solutions of the nine dimensional Einstein equations. Using combined numerical and analytical methods we give evidence that within this model the Schwarzschild-Tangherlini black hole is asymptotically stable. In addition, we briefly discuss the critical behavior at the threshold of black hole formation.Comment: 4 pages, 4 figure

From simple to complex networks: inherent structures, barriers and valleys in the context of spin glasses

Given discrete degrees of freedom (spins) on a graph interacting via an energy function, what can be said about the energy local minima and associated inherent structures? Using the lid algorithm in the context of a spin glass energy function, we investigate the properties of the energy landscape for a variety of graph topologies. First, we find that the multiplicity Ns of the inherent structures generically has a lognormal distribution. In addition, the large volume limit of ln/ differs from unity, except for the Sherrington-Kirkpatrick model. Second, we find simple scaling laws for the growth of the height of the energy barrier between the two degenerate ground states and the size of the associated valleys. For finite connectivity models, changing the topology of the underlying graph does not modify qualitatively the energy landscape, but at the quantitative level the models can differ substantially.Comment: 10 pages, 9 figs, slightly improved presentation, more references, accepted for publication in Phys Rev

Steam as the working fluid for power recovery from exhaust gases by means of screw expanders

Rankine cycle systems, using steam as a working fluid, are not well suited to the recovery of power fromheat sources in the 300-450 °C temperature range, such as internal combustion engine exhaust gases, mainly due to the relatively large enthalpy of vaporization of water. Admitting the steam to the expander as vapour approximately 50 per cent dry, would be preferable but turbines cannot be used to expand vapours from this state. However, screw expanders can operate well in this mode. It is shown that, apart from being environmentally benign and free from flammability risks, a screw-driven wet steam cycle system can recover power from engine exhaust gases, with comparable efficiencies to turbine-driven systems using organic fluids at a significantly lower cost per unit output

Steam as the working fluid for power recovery from exhaust gases by means of screw expanders

Rankine cycle systems, using steam as a working fluid, are not well suited to the recovery of power fromheat sources in the 300-450 °C temperature range, such as internal combustion engine exhaust gases, mainly due to the relatively large enthalpy of vaporization of water. Admitting the steam to the expander as vapour approximately 50 per cent dry, would be preferable but turbines cannot be used to expand vapours from this state. However, screw expanders can operate well in this mode. It is shown that, apart from being environmentally benign and free from flammability risks, a screw-driven wet steam cycle system can recover power from engine exhaust gases, with comparable efficiencies to turbine-driven systems using organic fluids at a significantly lower cost per unit output

Fisheries local action groups, small-scale fisheries and territorial development

\ua9 2024 The Authors. Sociologia Ruralis published by John Wiley & Sons Ltd on behalf of European Society for Rural Sociology. In comparison to the wealth of critical evaluation of LEADER (i.e., Liaison entre actions de d\ue9veloppement de l\u27\ue9conomie rurale), there has been no consolidated attempt to reflect on the contribution of Fisheries Local Action Groups (FLAGs), now entering their third EU programming period. Set up in the image of LEADER, and a novel governance instrument within the Common Fisheries Policy (CFP), FLAGs aim to activate local responses that build resilience and adaptability within the fisheries sector and wider communities. In addition to introducing the accompanying articles that make up this special issue of Sociologia Ruralis, our article gives an account of the emergence of community-led local development (CLLD) in fisheries and the attributes that have characterised the application of the LEADER approach within a fisheries-territorial development context. In many cases, FLAGs have led to improved relationships between the small-scale fishing sector and wider local social and economic networks, helping the sector reimagine its role within local economies. Yet outcomes vary as the FLAG approach has been applied across different cultural and institutional settings. There are indications that the system is becoming enveloped by wider priorities of coastal development and blue growth. Yet FLAGs may well provide a successful test case for widening participation in the CFP and upscaling integration of the fishing industry within local and regional economies. For CLLD in general, they are a reminder of the value of a differentiated CLLD approach tailored to different sectoral-territorial contexts