Recent science education reforms have placed a large emphasis on inquiry-based teaching strategies as an effective way of improving conceptual understanding of science principles, comprehension of the nature of scientific inquiry, and development of the abilities for inquiry (NRC, 1996). To better understand the relationship between inquiry-based instruction and student...
Island systems and species are susceptible to extinction because of their small population size and an ecological naiveté from an evolutionary past lacking strong competition and predation. For example, only one-fifth of the world’s bird species occur on islands, yet more than 90% of the avian extinctions witnessed during historic...
Roots of greenhouse-grown peppermint (Mentha piperita L.) and spearmint (Mentha spicata L.)
plants and in vitro-grown shoot cultures were inoculated with Verticillium dahliae conidial suspensions to
study symptom development, detection, and elimination of the V. dahliae. There were significant
differences in the symptom expression of control and infected shoot cultures...
Verticicladiella wageneri Kendr. is a vascular wilt pathogen of
Douglas-fir in the Pacific Northwest, The disease is characterized by
black staining of colonized sapwood; crown symptoms are those typical
of a wilting syndrome. Histopathological studies revealed that the
pathogen is limited to the xylem but causes vascular dysfunction in
both...
Phytophthora cinnamomi is a soilborne pathogen that causes root rot disease of highbush blueberry (Vaccinium corymbosum L.). When new installations of susceptible blueberry cultivars are infected with P. cinnamomi, plants often fail to grow significant new tissue, greatly reducing yields over the life of the planting. Chemical fungicides are available...
The impact that pesticides may have had on the mortality rates and productivity rates of non-game birds during the last 25 years was evaluated by studying the population dynamics of 16 species. A mathematical model showing the relationships between population parameters that yielded stable populations was developed. The information needed...
Recreational fishing has a long history in the USA, developing from the subsistence fisheries of Native Americans together with a partial subsistence fishery of later immigrants. Marine, diadromous, and aquatic taxa are targeted, including both vertebrates and macroinvertebrates. This paper defines recreational fishing, describes the main fishing techniques, identifies target...
Successful cryopreservation of all biological specimens would have an untold positive impact on medicine and scientific research. However, cryopreservation of the most complex biological specimens, such as tissues and organs, remains elusive. Vitrification, or ice-free cryopreservation, is promising for cryopreservation of complex specimens. The biggest challenge, though, is the toxicity...
A greenhouse experiment was conducted in 1991 and in
1992 to determine the effect of soil water pressure on
potato (cv Russet Burbank) plant growth and infection by
Verticillium dahliae. Soil water pressures of -0.01,
-0.03, -0.08, or -0.15 MPa were combined factorially with
two inoculum concentrations, 0 or 10...
In the last decade, there has been renewed interest in the use of granulocyte transfusions to treat infections in individuals with compromised immune systems. However, granulocytes only remain functional for about a day after isolation and this short shelf life is a significant drawback. Cryopreservation would allow long term storage...