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Restoration Ecology at 25 years: the editors reflect on how we got here
Similarity and Diversity in Macrophage Activation by Nematodes, Trematodes, and Cestodes
This review summarizes current knowledge of macrophages in helminth infections, with a focus not only on delineating the striking similarities in macrophage phenotype between diverse infections but also on highlighting the differences. Findings from many different labs illustrate that macrophages in helminth infection can act as anti-parasite effectors but can also act as powerful immune suppressors. The specific role for their alternative (Th2-mediated) activation in helminth killing or expulsion versus immune regulation remains to be determined. Meanwhile, the rapid growth in knowledge of alternatively activated macrophages will require an even more expansive view of their potential functions to include repair of host tissue and regulation of host metabolism
Impact of future climate change on water temperature and thermal habitat for keystone fishes in the Lower Saint John River, Canada
Water temperature is a key determinant of biological processes in rivers. Temperature in northern latitude rivers is expected to increase under climate change, with potentially adverse consequences for cold water-adapted species. In Canada, little is currently known about the timescales or magnitude of river temperature change, particularly in large (≥104 km2) watersheds. However, because Canadian watersheds are home to a large number of temperature-sensitive organisms, there is a pressing need to understand the potential impacts of climate change on thermal habitats. This paper presents the results of a study to simulate the effects of climate change on the thermal regime of the lower Saint John River (SJR), a large, heavily impounded, socio-economically important watershed in eastern Canada. The CEQUEAU hydrological-water temperature model was calibrated against river temperature observations and driven using meteorological projections from a series of regional climate models. Changes in water temperature were assessed for three future periods (2030–2034, 2070–2074 and 2095–2099). Results show that mean water temperature in the SJR will increase by approximately ~1 °C by 2070–2074 and a further ~1 °C by 2095–2099, with similar findings for the maximum, minimum and standard deviation. We calculated a range of temperature metrics pertaining to the Atlantic Salmon and Striped Bass, key species within the SJR. Results show that while the SJR will become increasingly thermally-limiting for Atlantic Salmon, the Striped Bass growth season may actually lengthen under climate change. These results provide an insight into how climate change may affect thermal habitats for fish in eastern Canadian rivers
Program Assessment: A Structured, Systematic, Sustainable Example for Civil Engineers
As the outcomes-based accreditation process continues to evolve since its implementation six years ago, the standards for program assessment and continuous improvement are progressively being raised and many schools struggle with what is required. This paper offers an example of a structured, systematic, sustainable assessment program implemented by the civil engineering program at the United States Military Academy. The process is compatible with the university assessment process and has eight years of documented results. The assessment includes fast loop and slow loop cycles that accomplish very different things. Other features include standardized course assessments, embedded indicators, performance measures for all outcomes and objectives, advisory boards, feedback from all constituencies, faculty involvement, and closing of the feedback loop
Morphological Variation of Rusty Crayfish Orconectes rusticus (Cambaridae) with Gender and Local Scale Spatial Gradients
We tested for the influence of gender, stream, and urbanization on morphological variation in rusty crayfish (Orconectes rusticus) in an east-central Indiana, US watershed. We used geometric morphometrics to characterize shape and tested for differences among and within sites. Males had shallower rostrum, increased head width and length, decreased abdomen and cephalothorax width and length, and increased telson length compared to females. Morphology of males did not vary with stream or along an urban gradient. The morphology of females varied with stream and along an urban gradient. Female shapes from small creek sites were stouter and less fusiform than larger river specimens. Following an urban gradient, females exhibited an increasingly reduced abdominal and telson area and a more fusiform rostrum. Morphological variation is linked with adaptation and subsequent success of aquatic taxa. Disentangling the potential influences on crayfish morphology has implications for improved understanding of ecosystem structure and conservation
Ariel - Volume 2 Number 2
Editors
Delvyn C. Case, Jr.
Paul M. Fernhoff
News Editors
Richard Bonanno
Daniel B. Gould
Ronald A. Hoffman
Lay-Out Editor
Carol Dolinskas
Sports Editor
James J. Nocon
Contributing Editors
MichaeI J. Blecker
Lin Sey Edwards
Jack Guralnik
W. Cherry Light
Features Editor
Donald A. Bergman
Stephen P. Flynn
Business Manager
Nick Grego
Public Relations
Robin A. Edward
COMPTEL neutron response at 17 MeV
The Compton imaging telescope (COMPTEL) instrument of the Gamma Ray Observatory was exposed to 17 MeV d,t neutrons prior to launch. These data were analyzed and compared with Monte Carlo calculations using the MCNP(LANL) code. Energy and angular resolutions are compared and absolute efficiencies are calculated at 0 and 30 degrees incident angle. The COMPTEL neutron responses at 17 MeV and higher energies are needed to understand solar flare neutron data
Optical angular momentum in a rotating frame
It is well established that light carrying orbital angular momentum (OAM) can be used to induce a mechanical torque causing an object to spin. We consider the complementary scenario: will an observer spinning relative to the beam axis measure a change in OAM as a result of their rotational velocity? Remarkably, although a linear Doppler shift changes the linear momentum of a photon, the angular Doppler shift induces no change in the angular momentum. Further, we examine the rotational Doppler shift in frequency imparted to the incident light due to the relative motion of the beam with respect to the observer and consider what must happen to the measured wavelength if the speed of light c is to remain constant. We show specifically that the OAM of the incident beam is not affected by the rotating observer and that the measured wavelength is shifted by a factor equal and opposite to that of the frequency shift induced by the rotational Doppler effect
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