GNSS-based monitoring and mapping of shoreline position in support of planning and management of Matinhos/PR (Brazil)

Monitoring and mapping variations in shoreline location is an activity that can be undertaken using several different techniques of data collection, e.g., photogrammetric restitution, satellite images, LiDAR (Light Detection and Ranging) or classical topographical surveys to support coastal environmental protection such as identifying flood risk areas. The global navigation satellite system (GNSS) has been employed by the Federal University of Parana (UFPR) as part of their research into the application of geodetic survey methods for shoreline mapping in coastal environments since 1996. The advantages of using GNSS are accuracy and productivity, given that a great number of points can be determined within a short period of time at decimeter-level accuracy. In this work, GNSS relative kinematic positioning approach was applied to monitor Matinhos coastal district of Brazil. Other important data, such as the high- and low-tide marks, all obtained using GNSS, and thematic maps have also been incorporated.Through the reanalysis of historical surveys, it is possible to make some conclusions about the shoreline dynamics and to use this information as material in support of the planning and management of the coastal environment, for example, when planning engineering works that set out to minimize coastal erosion and for urban planning. The results achieved in this work include defining the position of the shoreline for 2008, developing the thematic map of the shoreline, the quantification of the advance and retreat of the shoreline between 2001 and 2008, and a map showing those critical areas where the shoreline position is equal to the high-tide water line. GNSS-based method offers quicker, all-weather, highly accurate and continuously updatable shoreline positional time series relevant for monitoring, thus enabling quicker management decisions to be undertaken, which may be of benefit to coastal engineering applications

Sensing electric and magnetic fields with Bose-Einstein Condensates

We discuss the application of Bose-Einstein condensates (BECs) as sensors for magnetic and electric fields. In an experimental demonstration we have brought one-dimensional BECs close to micro-fabricated wires on an atom chip and thereby reached a sensitivity to potential variations of ~10e-14eV at 3 micron spatial resolution. We demonstrate the versatility of this sensor by measuring a two-dimensional magnetic field map 10 micron above a 100-micron-wide wire. We show how the transverse current-density component inside the wire can be reconstructed from such maps. The field sensitivity in dependence on the spatial resolution is discussed and further improvements utilizing Feshbach resonances are outlined.Comment: 4 pages, 3 figure

High-order combination effects and biological robustness

Biological systems are robust, in that they can maintain stable phenotypes under varying conditions or attacks. Biological systems are also complex, being organized into many functional modules that communicate through interlocking pathways and feedback mechanisms. In these systems, robustness and complexity are linked because both qualities arise from the same underlying mechanisms. When perturbed by multiple attacks, such complex systems become fragile in both theoretical and experimental studies, and this fragility depends on the number of agents applied. We explore how this relationship can be used to study the functional robustness of a biological system using systematic high-order combination experiments. This presents a promising approach toward many biomedical and bioengineering challenges. For example, high-order experiments could determine the point of fragility for pathogenic bacteria and might help identify optimal treatments against multi-drug resistance. Such studies would also reinforce the growing appreciation that biological systems are best manipulated not by targeting a single protein, but by modulating the set of many nodes that can selectively control a system's functional state

Pulsed Jet Dynamics of Squid Hatchlings at Intermediate Reynolds Numbers

Squid paralarvae (hatchlings) rely predominantly on a pulsed jet for locomotion, distinguishing them from the majority of aquatic locomotors at low/intermediate Reynolds numbers (Re), which employ oscillatory/undulatory modes of propulsion. Although squid paralarvae may delineate the lower size limit of biological jet propulsion, surprisingly little is known about the hydrodynamics and propulsive efficiency of paralarval jetting within the intermediate Re realm. To better understand paralarval jet dynamics, we used digital particle image velocimetry (DPIV) and high-speed video to measure bulk vortex properties ( e. g. circulation, impulse, kinetic energy) and other jet features [ e. g. average and peak jet velocity along the jet centerline (Uj and Ujmax, respectively), jet angle, jet length based on the vorticity and velocity extents (Lω and LV, respectively), jet diameter based on the distance between vorticity peaks (Dω), maximum funnel diameter (DF), average and maximum swimming speed (U and Umax, respectively)] in free-swimming Doryteuthis pealeii paralarvae (1.8 mm dorsal mantle length) (Resquid=25-90). Squid paralarvae spent the majority of their time station holding in the water column, relying predominantly on a frequent, high-volume, vertically directed jet. During station holding, paralarvae produced a range of jet structures from spherical vortex rings ( Lω/Dω=2.1, LV/DF=13.6) to more elongated vortex ring structures with no distinguishable pinch-off (Lω/Dω= 4.6, LV/DF=36.0). To swim faster, paralarvae increased pulse duration and Lω/Dω, leading to higher impulse but kept jet velocity relatively constant. Paralarvae produced jets with low slip, i.e. ratio of jet velocity to swimming velocity (Uj/U or Ujmax/Umax), and exhibited propulsive efficiency [ηpd=74.9 +/- 8.83% (+/- s.d.) for deconvolved data] comparable with oscillatory/ undulatory swimmers. As slip decreased with speed, propulsive efficiency increased. The detection of high propulsive efficiency in paralarvae is significant because it contradicts many studies that predict low propulsive efficiency at intermediate Re for inertial forms of locomotion

Swimming Dynamics and Propulsive Efficiency of Squids Throughout Ontogeny

Synopsis Squids encounter vastly different flow regimes throughout ontogeny as they undergo critical morphological changes to their two locomotive systems: the fins and jet. Squid hatchlings (paralarvae) operate at low and intermediate Reynolds numbers (Re) and typically have rounded bodies, small fins, and relatively large funnel apertures whereas juveniles and adults operate at higher Re and generally have more streamlined bodies, larger fins, and relatively small funnel apertures. These morphological changes and varying flow conditions affect swimming performance in squids. To determine how swimming dynamics and propulsive efficiency change throughout ontogeny, digital particle image velocimetry (DPIV) and kinematic data were collected from an ontogenetic range of long-finned squid Doryteuthis pealeii and brief squid Lolliguncula brevis swimming in a holding chamber or water tunnel (Re=20-20 000). Jet and fin wake bulk properties were quantified, and propulsive efficiency was computed based on measurements of impulse and excess kinetic energy in the wakes. Paralarvae relied predominantly oil a vertically directed, high frequency, low velocity jet as they bobbed up and down in the water column. Although sonic spherical vortex rings were observed, most paralarval jets consisted of an elongated vertical region of variable length with no clear pinch-off of a vortex ring from the trailing tail component. Compared with paralarvae, juvenile and adult squid exhibited a more diverse range of swimming strategies, involving greater overall locomotive fin reliance and multiple fin and jet wake modes with better defined vortex rings. Despite greater locomotive flexibility, jet propulsive efficiency of juveniles/adults was significantly lower than that of paralarvae, even when juvenile/adults employed their highest efficiency jet mode involving the production of periodic isolated vortex rings with each jet pulse. When the fins were considered together with the jet for several juvenile/adult swimming sequences, overall propulsive efficiency increased, suggesting that fin contributions are important and Should not be overlooked in analyses of the swimming performance of squids. The fins produced significant thrust and consistently had higher propulsive efficiency than did the jet. One particularly important area of future Study is the determination of coordinated jet/fin wake modes that have the greatest impact oil propulsive efficiency. Although such research would be technically challenging, requiring new, powerful, 3D approaches, it is necessary for a more comprehensive assessment of propulsive efficiency of the squid dual-mode locomotive system

Labor Movements: From the Specifications of the Panama Canal to Robotic Patents

This paper is part of an ongoing collaboration between architecture faculty and students. The paper highlights two student projects from a recent research studio focused on the link between regulatory documents (specifications, laws, codes, patents, etc.) and the political territories that connect building technology with the movements of construction labor. Each project interconnects two types of movement: (1) physical movements of people, materials, and machines (2) political movements and colonial structures of power. The former are visible and have limited durations, while the latter are seemingly invisible but with enduring consequences. The contemporary effects of these movements are latent in the underexamined histories of written regulatory documents. In the first project, these two types of movement intersect in the construction of the Panama Canal. The strategy for this analysis is based on visualizing concrete specifications, sanitation laws, and construction images collected from the Nichols Notebook Archive. These documents juxtapose unpredictable site conditions, yellow fever and the movement of people, with the pursuit of material predictability, such as engineered concrete. These two scales collide at the margins of the oceanic trade route, stressing the tensions between exploitative imperialist bodies and the bodies of local and migrant workers. Overlapping with the timeline of the Panama Canal construction, the second student project connects the language of twentieth century U.S. Labor Acts with the evolution of KUKA Robotic Patents. The influx of twentyfirst century industrial construction robots highlights the political implications of choreographing movement on the worksite. Both projects resulted in a series of strategies used to visualize the movements of labor, arguing that labor conditions are central to technological processes, yet peripheral to traditional architectural discourse. Examining postcolonial theory and automation discourse through the study of written regulations makes a case for expanding transdisciplinary knowledge across multiple scales of visible and invisible movements

Hydrodynamics of Pulsed Jetting in Juvenile and Adult Brief Squid Lolliguncula Brevis: Evidence of Multiple Jet \u27Modes\u27 and Their Implications for Propulsive Efficiency

The dynamics of pulsed jetting in squids throughout ontogeny is not well understood, especially with regard to the development of vortex rings, which are common features of mechanically generated jet pulses (also known as starting jets). Studies of mechanically generated starting jets have revealed a limiting principle for vortex ring formation characterized in terms of a \u27formation number\u27 (F), which delineates the transition between the formation of isolated vortex rings and vortex rings that have \u27pinched off\u27 from the generating jet. Near F, there exists an optimum in pulse-averaged thrust with (potentially) low energetic cost, raising the question: do squids produce vortex rings and if so, do they fall near F, where propulsive benefits presumably occur? To better understand vortex ring dynamics and propulsive jet efficiency throughout ontogeny, brief squid Lolliguncula brevis ranging from 3.3 to 9.1 cm dorsal mantle length (DML) and swimming at speeds of 2.43-22.2cm s-1 (0.54-3.50 DML s-1) were studied using digital particle image velocimetry (DPIV). A range of jet structures were observed but most structures could be classified as variations of two principal jet modes: (1) jet mode I, where the ejected fluid rolled up into an isolated vortex ring; and (2) jet mode II, where the ejected fluid developed into a leading vortex ring that separated or \u27pinched off\u27 from a long trailing jet. The ratio of jet length [based on the vorticity extent (Lω] to jet diameter [based on peak vorticity locations (Dω] was \u3c3.0 for jet mode I and \u3e 3.0 for jet mode II, placing the transition between modes in rough agreement with F determined in mechanical jet studies. Jet mode II produced greater time-averaged thrust and lift forces and was the jet mode most heavily used whereas jet mode I had higher propulsive efficiency, lower slip, shorter jet periods and a higher frequency of fin activity associated with it. No relationship between Lω/Dω and speed was detected and there was no apparent speed preference for the jet modes within the speed range considered in this study; however, propulsive efficiency did increase with speed partly because of a reduction in slip and jet angle with speed. Trends in higher slip, lower propulsive efficiency and higher relative lift production were observed for squid \u3c5.0 cm DML compared with squid \u3e= 5.0 cm DML. While these trends were observed when jet mode I and II were equally represented among the size classes, there was also greater relative dependence on jet mode I than jet mode II for squid \u3c5.0 cm DML when all of the available jet sequences were examined. Collectively, these results indicate that similar to 5.0 cm DML is an important ontogenetic transition for the hydrodynamics of pulsed jetting in squids. The significance of our findings is that from early juvenile through to adult life stages, L. brevis is capable of producing a diversity of vortex ring-based jet structures, ranging from efficient short pulses to high-force longer duration pulses. Given that some of these structures had Lω/Dωs near F, and F represented the delineation between the two primary jet modes observed, fluid dynamics probably played an integral role in the evolution of squid locomotive systems. When this flexibility in jet dynamics is coupled with the highly versatile fins, which are capable of producing multiple hydrodynamic modes as well, it is clear that squid have a locomotive repertoire far more complex than orignally thought