USING LAND AS A CONTROL VARIABLE IN DENSITY-DEPENDENT BIOECONOMIC MODELS

The bioeconomic analysis of endangered species without consumptive values can be problematic when analysed with density-dependent models that assume a fixed environment size. Most bioeconomic models use harvest as a control variable, yet when modelling non-harvestable species, frequently the only variable under control of conservationists is the quantity of habitat to be made available. The authors explore the implications of this in a model developed to analyse the potential population recovery of New Zealand's yellow-eyed penguin. The penguin faces severe competition with man for the terrestrial resources required for breeding and has declined in population to perilously low levels. The model was developed to estimate the land use required for recovery and preservation of the species and to compare the results to current tourism-driven conservation efforts. It is demonstrated that land may serve as a useful control variable in bioeconomic models and that such a model may be useful for determining whether sufficient incentives exist to preserve a species. However, the model may generate less useful results for providing a specific estimate of the optimal allocation of land to such a species.Land Economics/Use,

BIOECONOMIC MODELLING OF ENDANGERED SPECIES CONSERVATION

Resource /Energy Economics and Policy,

Coordination and Sustainability of River Observing Activities in the Arctic

To understand and respond to changes in the world’s northern regions, we need a coordinated system of long-term Arctic observations. River networks naturally integrate across landscapes and link the terrestrial and ocean domains. Changes in river discharge reflect changes in the terrestrial water balance, whereas changes in water chemistry are linked to changes in biogeochemical processes and water flow paths. Sustained measurements of river water discharge and water chemistry are therefore essential components of an Arctic observing network. As we strive to establish and sustain long-term observations in the Arctic, these two measurements must be coupled. Although river discharge and chemistry measurements are already coupled to some extent within national boundaries, this is not done in a consistent and coordinated fashion across the pan-Arctic domain. As a consequence, data quality and availability vary widely among regions. International coordination of river discharge and chemistry measurements in the Arctic would be greatly facilitated by formal commitments to maintain a set of core sites and associated measurements that are mutually agreed upon among pan-Arctic nations. Involvement of the agencies currently operating river discharge gauges around the Arctic and establishment of an overarching coordination entity to implement shared protocols, track data quality, and manage data streams would be essential in this endeavor. Focused studies addressing scale-dependent relationships between watershed characteristics and water chemistry, in-stream processes, and estuarine and coastal dynamics are also needed to support interpretation and application of Arctic river observing data as they relate to land and ocean change

Pilot feasibility study of a simple regenerative peripheral nerve interface designed to diminish cutaneous dysesthesia after supraclavicular operations

Supraclavicular operations can be associated with postoperative cutaneous dysesthesia and hypersensitivity. Regenerative peripheral nerve interfaces, created by attaching the proximal end of a divided peripheral nerve into a viable muscle target, can promote neurite regrowth and neuromuscular connections to help suppress painful nerve hyperactivity. During 40 consecutive operations for neurogenic thoracic outlet syndrome, we demonstrated that division of at least one of the superficial supraclavicular cutaneous sensory nerve branches was necessary in 98% of cases. We subsequently developed a novel regenerative peripheral nerve interface for supraclavicular operations using the adjacent omohyoid muscle and have described the technical steps involved in this procedure

Quantitative Assessment of the Anatomical Footprint of the C1 Pedicle Relative to the Lateral Mass: A Guide for C1 Lateral Mass Fixation

Study Design: Anatomic study. Objectives: To determine the relationship of the anatomical footprint of the C1 pedicle relative to the lateral mass (LM). Methods: Anatomic measurements were made on fresh frozen human cadaveric C1 specimens: pedicle width/height, LM width/height (minimum/maximum), LM depth, distance between LM’s medial aspect and pedicle’s medial border, distance between LM’s lateral aspect to pedicle’s lateral border, distance between pedicle’s inferior aspect and LM’s inferior border, distance between arch’s midline and pedicle’s medial border. The percentage of LM medial to the pedicle and the distance from the center of the LM to the pedicle’s medial wall were calculated. Results: A total of 42 LM were analyzed. The C1 pedicle’s lateral aspect was nearly confluent with the LM’s lateral border. Average pedicle width was 9.0 ± 1.1 mm, and average pedicle height was 5.0 ± 1.1 mm. Average LM width and depth were 17.0 ± 1.6 and 17.2 ± 1.6 mm, respectively. There was 6.9 ± 1.5 mm of bone medial to the medial C1 pedicle, which constituted 41% ± 9% of the LM’s width. The distance from C1 arch’s midline to the medial pedicle was 13.5 ± 2.0 mm. The LM’s center was 1.6 ± 1 mm lateral to the medial pedicle wall. There was on average 3.5 ± 0.6 mm of the LM inferior to the pedicle inferior border. Conclusions: The center of the lateral mass is 1.6 ± 1 mm lateral to the medial wall of the C1 pedicle and approximately 15 mm from the midline. There is 6.9 ± 1.5 mm of bone medial to the medial C1 pedicle. Thus, the medial aspect of C1 pedicle may be used as an anatomic reference for locating the center of the C1 LM for screw fixation

The organization and management of the Virtual Astronomical Observatory

The U.S. Virtual Astronomical Observatory (VAO; http://www.us-vao.org/) has been in operation since May 2010. Its goal is to enable new science through efficient integration of distributed multi-wavelength data. This paper describes the management and organization of the VAO, and emphasizes the techniques used to ensure efficiency in a distributed organization. Management methods include using an annual program plan as the basis for establishing contracts with member organizations, regular communication, and monitoring of processes.Comment: 9 pages, 3 figures. SPIE Conference 8449: Modeling, Systems Engineering, and Project Management for Astronomy

Investigation of generic hub fairing and pylon shapes to reduce hub drag

Reported are investigations of fairing configurations pointed toward substantially reducing hub drag. Experimental investigations have shown the importance of hub-fairing camber, lower-surface curvature, and relative size of the drag. The significance of pylon and hub fairings in combination have also been shown. Model test data presented here documented these findings, and also showed the effect of gaps and hub-fairing inclination angle on drag. From a drag standpoint, the best hub fairing had a circular arc, upper-surface curvature, a flat bottom surface, and 8.75% camber

High Quality Ultrathin Bi2Se3 Films on CaF2 and CaF2/Si by Molecular Beam Epitaxy with a Radio Frequency Cracker Cell

Here we report a method to fabricate high quality Bi2Se3 thin films using molecular beam epitaxy with a radio frequency cracker cell as an atomic selenium source. With rates close to exact stoichiometry, optimal layer-by-layer growth of high quality Bi2Se3 thin films with smooth surfaces, has been achieved on CaF2(111) substrates and Si(111) substrates with a thin CaF2 buffer layer(CaF2/Si). Transport measurements show a characteristic weak antilocalization mangnetoresistance, with emergence of weak localization in the ultrathin film limit. Quantum Oscillations attributed to the topological surface states have been observed, including in films on CaF2/Si

Lift and moment equations for oscillating airfoils in an infinite unstaggered cascade

Aerodynamic coefficients similar to those of the isolated airfoil are obtained as functions of the cascade geometry and the phasing between successive blades; the phasings considered are zero, 90 degrees, and 180 degrees. These aerodynamic coefficients are plotted for the special case when all the airfoils are vibrating in bending in phase (360 degree phasing). It is shown that the effect of cascading for this case is to reduce greatly the aerodynamic damping. (author