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Seafloor Pressure Measurements of Nonlinear Internal Waves
Get PDFHighly resolved pressure measurements on the seafloor over New Jersey’s continental shelf reveal the pressure signature of nonlinear internal waves of depression as negative pressure perturbations. The sign of the perturbation is determined by the dominance of the internal hydrostatic pressure (p⁰Wh) due to isopycnal displacement over the contributions of external hydrostatic pressure (ρ₀gηH; ηH is surface displacement) and nonhydrostatic pressure (p₀nh), each of opposite sign to p⁰Wh. This measurement represents experimental confirmation of the wave-induced pressure signal inferred in a previous study by Moum and Smyth.There was a press error in Fig. 10 of Moum and Nash (2008). The legend in Fig. 10a was shown in black and white instead of color. The correct figure and caption as they were meant to appear are shown below. The staff of the Journal of Physical Oceanography regrets any inconvenience this error may have caused.Keywords: Pressure, Internal waves, Continental shelf, Waves\, oceani
Real-World Performance: Physical Activity, Play, and Object-Related Behaviors of Toddlers With and Without Disabilities
No full textPURPOSE: To describe and compare the occurrence and co-occurrence of physical activity (PA), play, and object-related behaviors in toddlers with and without disabilities.
METHODS: Participants included 23 toddlers (21 with typical development (TD) and 2 with disabilities). Direct observation was used to describe the type and level of PA, play interactions, and object-related behaviors through video recordings.
RESULTS: Toddlers demonstrated high variability, occurrence, and co-occurrence of all behaviors. Toddlers with disabilities displayed less variability, occurrence, and co-occurrence of several behaviors.
CONCLUSIONS: Toddlers with TD engage simultaneously in PA, play, and object-related behaviors for about 3 hours in a typical day. This same level of co-occurrence of behaviors may not be observed for children with disabilities. Intervention providers are encouraged to consider the behaviors of toddlers with TD, beyond the findings of this pilot study, as the reference standard when implementing technology and intervention strategies for children with disabilities.This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Wolters Kluwer Health, Inc., and Section on Pediatrics of the American Physical Therapy Association. It can be found at: http://journals.lww.com/pedpt/pages/default.aspxKeywords: motor skills, play, object manipulation, children with disabilities, disability, human, preschool, child, spatial behavior, male, female, physical activityKeywords: motor skills, play, object manipulation, children with disabilities, disability, human, preschool, child, spatial behavior, male, female, physical activit
On the Economics of Virtual Water Trade
Get PDFVirtual water trade is increasingly recognized as a useful metaphor for thinking about freshwater resources in an international context. Its legitimacy in terms of economic theory has been questioned by a number of authors, however. In this article I develop new theoretical results that place the virtual water concept on a firm economic foundation, and which correct several misconceptions within the existing literature on virtual water economics.Keywords: Water, International tradeKeywords: Water, International trad
OSU Extension pesticide properties database
No full textThe OSU Extension Pesticide Properties Database is organized alphabetically by common name. Eight parameters describing pesticide physical and chemical properties are presented. The database includes pesticides that may not currently be registered for use in Oregon, but may have been used historically or may currently be registered for use in other states.Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalo
CrumpByronCEOASMetacommunityDynamicsBacteria_SupplementaryMaterial.pdf
No full textTo understand mechanisms linking ecosystem processes and microbial diversity in freshwater ecosystems, bacterial productivity and the metacommunity dynamics of species sorting and mass effects were investigated in an 18 ha headwater lake in northern Alaska. On most sampling dates, the phylogenetic composition of bacterial communities in inflowing streams (inlets) was strikingly different than that in the lake and the outflowing stream (outlet) (16S DGGE fingerprinting), demonstrating the shift in composition that occurs as these communities transit the lake. Outlet and downstream communities were also more productive than inlet and upstream communities (¹⁴C-leucine incorporation). Inlet bacteria transplanted to the outlet stream in dialysis bags were equally or less productive than control bacteria, suggesting that the inlet bacteria are capable of growing under lake conditions, but do not remain abundant because of species sorting in the lake. Outlet bacteria (representative of epilimnetic bacteria) transplanted to the inlet stream were less productive than control bacteria, suggesting that lake bacteria are not as well adapted to growing under inlet conditions. Based on water density, inlet stream water and bacteria generally entered the lake at the base of the epilimnion. However, during low to medium flow in the inlet stream the residence time of the epilimnion was too long relative to bacterial doubling times for these allochthonous bacteria to have a mass effect on the composition of outlet bacteria. The highest community similarity between inlet and outlet bacteria was detected after a large rain event in 2003, with over 61% similarity (average non-storm similarities were 39 ± 8%). While mass effects may be important during large storm events, species sorting appears to be the predominant mechanism structuring bacterial communities within the lake, leading to the assembly of a lake community that has lost some ability to function in stream habitats.Keywords: species sorting, transplant experiments, metacommunity theory, aquatic microbiology, arctic, mass effects, bacterial productionKeywords: species sorting, transplant experiments, metacommunity theory, aquatic microbiology, arctic, mass effects, bacterial productio
JonesInvasiveMammalEradicationTable2.pdf
No full textMore than US$21 billion is spent annually on biodiversity conservation. Despite their importance for preventing or slowing extinctions and preserving biodiversity, conservation interventions are rarely assessed systematically for their global impact. Islands house a disproportionately higher amount of biodiversity compared with mainlands, much of which is highly threatened with extinction. Indeed, island species make up nearly two-thirds of recent extinctions. Islands therefore are critical targets of conservation. We used an extensive literature and database review paired with expert interviews to estimate the global benefits of an increasingly used conservation action to stem biodiversity loss: eradication of invasive mammals on islands. We found 236 native terrestrial insular faunal species (596 populations) that benefitted through positive demographic and/or distributional responses from 251 eradications of invasive mammals on 181 islands. Seven native species (eight populations) were negatively impacted by invasive mammal eradication. Four threatened species had their International Union for the Conservation of Nature (IUCN) Red List extinction-risk categories reduced as a direct result of invasive mammal eradication, and no species moved to a higher extinction-risk category. We predict that 107 highly threatened birds, mammals, and reptiles on the IUCN Red List—6% of all these highly threatened species—likely have benefitted from invasive mammal eradications on islands. Because monitoring of eradication outcomes is sporadic and limited, the impacts of global eradications are likely greater than we report here. Our results highlight the importance of invasive mammal eradication on islands for protecting the world's most imperiled fauna.Keywords: invasive species, conservation, eradication, island, restoratio
R26.jpg
No full textThis thesis is an effort to formalize and document some of the changes occuring in the Warwar Valley of Gongola State, Nigeria, West Africa. The documentation will comprise a photographic study over time accompanied by an ethnographic narrative. Information gathered from photographic images, field notes and the anthropological record will then be applied to a cultural-ecological model based on the theory of Julian Steward. The Mambilla people inhabiting the Warwar Valley are changing their traditional agricultural land use patterns and value system due to the influx of new ideas, notably the introduction of a cash economy. This cultural change has affected environmental change, observable in soil erosion
Generalized crack closure analysis for elements with arbitrarily-placed side nodes and consistent nodal forces
Get PDFA new approach was developed for the evaluation of energy release rate by the virtual crack closure technique in quadratic and linear elements. The generalized method allows arbitrary placement of the side nodes for quadratic elements and thus includes both standard elements, with mid-side nodes, and singularity elements, with quarter-point nodes, as special cases of one general equation. It also accounts for traction-loaded cracks. The new derivation revealed that the proper nodal forces needed for crack closure calculations should be the newly-defined “nodal edge forces,” rather than the global or element forces from standard finite element analysis results. A method is derived for calculating nodal edge forces from global forces. These new forces affect energy release rate calculations for singularity elements and for problems with traction-loaded cracks. Several sample calculations show that the new approach gives improved accuracy.Keywords: Crack closure, Finite elements analysis, FractureKeywords: Crack closure, Finite elements analysis, Fractur
Development of a forest data management system useful for research, instruction and property management
No full textThe establishment of a computerized data
management system (DMS) for the OSU College of
Forestry's properties is documented. The properties
consist of about 14,000 acres and are
used by many departments at OSU for instruction
and research, as well as being managed for financial
return.
The steps followed in establishing the DMS
were:
1.The potential users of the DMS that would
assist in its establishment were identified.
2.Both the intended applications of the DMS
and the variables to be stored were determined. 3.The capabilities that the basic DMS must have
so that, with supplementary programming, the
users' needs could be met were defined.
4.The basic DMS's located in the literature
review were evaluated for adequate capabilities
of data storage, retrieval, update, deletion
and addition.
5.The DMS's having adequate capabilities were
compared in several other areas, such as,
compatibility with existing OSU equipment and
cost of implementation. A DMS was then
selected for implementation.
6.The DMS was implemented. This included
determing data structure in storage, writing
supplementary programs, and writing a user's
manual.
7.The DMS was evaluated for how well it met the
users' needs, ease of use, cost of use, and
ease of modification.
The steps followed, the defined users' needs
and the conclusions presented should be applicable
to any similar situation