An evaluation of thematic mapper simulator data for the geobotanical discrimination of rock types in Southwest Oregon

Rock type identification may be assisted by the use of remote sensing of associated vegetation, particularly in areas of dense vegetative cover where surface materials are not imaged directly by the sensor. The geobotanical discrimination of ultramafic parent materials was investigated and analytical techniques for lithologic mapping and mineral exploration were developed. The utility of remotely sensed data to discriminate vegetation types associated with ultramafic parent materials in a study area in southwest Oregon were evaluated. A number of specific objectives were identified, which include: (1) establishment of the association between vegetation and rock types; (2) examination of the spectral separability of vegetation types associated with rock types; (3) determination of the contribution of each TMS band for discriminating vegetation associated with rock types and (4) comparison of analytical techniques for spectrally classifying vegetation

Participative critical enquiry in graduate field-based learning

This paper outlines a critical pedagogic approach to field-based learning (FBL) at graduate level. Drawing on student experience stemming from a FBL module and as part of an MA programme in Environment, Society and Development, the paper addresses the complexities associated with student-led, participative critical enquiry during fieldwork in Sarajevo, Bosnia-Herzegovina. The paper examines emerging student discourses through a group assessment and a series of individual reflective journals. Both are contextualised in relation to FBL module learning outcomes. Finally, aspects of fieldwork influencing the feasibility and effectiveness of participative critical enquiry as a field-based pedagogic endeavour are considered

A resource survey of the coastal lands from Vlaming Head to Tantabiddi Well, West Cape Range region

The report comprise four parts; a brief review of the area\u27s climate, discussion of the geomorphology of the major landform units, an assessment of the potential erosion hazards of the surveyed landforms, and recommendations for development

American Dipper, Cinclus mexicanus, Preys Upon Larval Tailed Frogs, Ascaphus truei

The American Dipper (Cinclus mexicanus) is an aquatic songbird that inhabits fast-flowing mountain streams in western North America. Although dippers are known to feed primarily on aquatic invertebrates, they will also eat juvenile fish and salmon eggs when available. In 2002, while monitoring and photographing nesting activities of the American dipper, we observed and photographed adult dippers capturing Tailed Frog (Ascaphus truei) tadpoles and feeding them to their young. This note is intended to document a rarely observed occurrence and identify interactions between two relatively uncommon species

Rapid and quantitative determination of hexanal in cooked muscle foods

A simple and rapid method was developed to quantify hexanaJ in cooked muscle foods. The method involves extraction of the 2,4-dinitrophenylhydrazones of carbonyls with hexane and their separation by reversed-phased high performance liquid chromatography. The method compared well with the classical thiobarbituric acid test. The method was successfully used to quantify hexana) in cooked beef and pork burgers during storage at 4 °C for up to 1 week as well as in cooked turkey burgers after diet supplementation with vitamin E. After 7 days' storage at 4 °C, the contents of hexanal increased from 0.71 to 22.50 μ.mol/kg in beef burgers, from 0.89 to 32.7S μmol / kg in pork burgers and from 1.31 to S2.16 μmol / kg in turkey burgers (20 mg vitamin E per kg feed). Supplementation of turkey feeds with 600 mg Yitamin E per kg resulted in a 24% reduction in hexanal content in cooked turkey burgers after storage for 7 days at 4 °C, compared to the control (unsupplemented) group

Population structures and levels of connectivity for Scyphozoan and Cubozoan jellyfish

Understanding the hierarchy of populations from the scale of metapopulations to mesopopulations and member local populations is fundamental to understanding the population dynamics of any species. Jellyfish by definition are planktonic and it would be assumed that connectivity would be high among local populations, and that populations would minimally vary in both ecological and genetic clade-level differences over broad spatial scales (i.e., hundreds to thousands of km). Although data exists on the connectivity of scyphozoan jellyfish, there are few data on cubozoans. Cubozoans are capable swimmers and have more complex and sophisticated visual abilities than scyphozoans. We predict, therefore, that cubozoans have the potential to have finer spatial scale differences in population structure than their relatives, the scyphozoans. Here we review the data available on the population structures of scyphozoans and what is known about cubozoans. The evidence from realized connectivity and estimates of potential connectivity for scyphozoans indicates the following. Some jellyfish taxa have a large metapopulation and very large stocks (>1000 s of km), while others have clade-level differences on the scale of tens of km. Data on distributions, genetics of medusa and polyps, statolith shape, elemental chemistry of statoliths and biophysical modelling of connectivity suggest that some of the ~50 species of cubozoans have populations of surprisingly small spatial scales and low levels of connectivity. Despite their classification as plankton, therefore, some scyphozoans and cubozoans have stocks of small spatial scales. Causal factors that influence the population structure in many taxa include the distribution of polyps, behavior of medusa, local geomorphology and hydrodynamics. Finally, the resolution of patterns of connectivity and population structures will be greatest when multiple methods are used

Cosmic Strings from Supersymmetric Flat Directions

Flat directions are a generic feature of the scalar potential in supersymmetric gauge field theories. They can arise, for example, from D-terms associated with an extra abelian gauge symmetry. Even when supersymmetry is broken softly, there often remain directions in the scalar field space along which the potential is almost flat. Upon breaking a gauge symmetry along one of these almost flat directions, cosmic strings may form. Relative to the standard cosmic string picture based on the abelian Higgs model, these flat-direction cosmic strings have the extreme Type-I properties of a thin gauge core surrounded by a much wider scalar field profile. We perform a comprehensive study of the microscopic, macroscopic, and observational characteristics of this class of strings. We find many differences from the standard string scenario, including stable higher winding mode strings, the dynamical formation of higher mode strings from lower ones, and a resultant multi-tension scaling string network in the early universe. These strings are only moderately constrained by current observations, and their gravitational wave signatures may be detectable at future gravity wave detectors. Furthermore, there is the interesting but speculative prospect that the decays of cosmic string loops in the early universe could be a source of ultra-high energy cosmic rays or non-thermal dark matter. We also compare the observational signatures of flat-direction cosmic strings with those of ordinary cosmic strings as well as (p,q) cosmic strings motivated by superstring theory.Comment: 58 pages, 16 figures, v2. accepted to PRD, added comments about baryogenesis and boosted decay products from cusp annihilatio

Do American Dippers Obtain a Survival Benefit from Altitudinal Migration?

Studies of partial migrants provide an opportunity to assess the cost and benefits of migration. Previous work has demonstrated that sedentary American dippers (residents) have higher annual productivity than altitudinal migrants that move to higher elevations to breed. Here we use a ten-year (30 period) mark-recapture dataset to evaluate whether migrants offset their lower productivity with higher survival during the migration-breeding period when they occupy different habitat, or early and late-winter periods when they coexist with residents. Mark-recapture models provide no evidence that apparent monthly survival of migrants is higher than that of residents at any time of the year. The best-supported model suggests that monthly survival is higher in the migration-breeding period than winter periods. Another well-supported model suggested that residency conferred a survival benefit, and annual apparent survival (calculated from model weighted monthly apparent survival estimates using the Delta method) of residents (0.511 ± 0.038SE) was slightly higher than that of migrants (0.487 ± 0.032). Winter survival of American dippers was influenced by environmental conditions; monthly apparent survival increased as maximum daily flow rates increased and declined as winter temperatures became colder. However, we found no evidence that environmental conditions altered differences in winter survival of residents and migrants. Since migratory American dippers have lower productivity and slightly lower survival than residents our data suggests that partial migration is likely an outcome of competition for limited nest sites at low elevations, with less competitive individuals being forced to migrate to higher elevations in order to breed