A summary of terminology used in tephra-related studies

The word ‘tephra’, derived from a Greek word for ash, is a collective term for all the unconsolidated, primary pyroclastic products of a volcanic eruption. We summarise here the meanings and applicability of this and related terms, including tephrostratigraphy, tephrochronology, tephrochronometry, tephrology, and cryptotephra. These and other tephra-based terms, some of which are erroneous or unnecessary, have been used in a wide range of stratigraphic and paleoenvironmental disciplines and in archaeology

The Influence of Information Signs on Visitor Distribution and Use

Lack of information is a primary factor accounting for visitors jamming recreation sites, overflowing onto highway rights-of-way and blocking facilities [5, p. 95]. In attempting to attain an even distribution of visitors, the importance of information signing as a management tool is often overlooked. Oxenfeldt indicates that advertising (information) alters behavior most efficiently when it supplies information customers are seeking [4, p. 471]. Tocher and Kearns noted in visitor characteristic studies that travelers seek different experiences when touring than when at home or work [6]. Information signs may lead the visitor to these different experiences. Hypothesizing that signs can influence facility use patterns, researchers at Utah State University in 1964 and 1965 conducted a visitor use and motivation study in the Logan Canyon Recreation Complex, Utah. (The original study from which portions of these data were obtained was initiated by S. Ross Tocher, Instructor, University of Michigan while he was a member of the College of Natural Resources Faculty at Utah State University.) This report focuses on two questions: (1) do information signs help distribute visitors more evenly? and (2) do information signs stimulate greater use of a previously unsigned roadside rest area

PCBs : exposures, effects, remediation, and regulation with special emphasis on PCBs in schools

Author Posting. © The Author(s), 2015. This is the author's version of the work. It is posted here by permission of Springer for personal use, not for redistribution. The definitive version was published in Environmental Science and Pollution Research 23 (2016): 1971-1974, doi:10.1007/s11356-015-5774-y.The Eighth International PCB Workshop: PCBs in Schools was held in Woods Hole, MA, October 5-9, 2014, and was attended by more than 130 scientists and other interested persons, including citizen’s groups and concerned parents. The program included a wide range of thematic areas. Presentations addressed essential questions and progress toward understanding mechanisms of PCB toxication and risks of PCB exposure. Presentations were also held illuminating several key PCB contamination problems.2016-12-0

Evolution: Lending a Helping Hand in Sperm Competition?

Most females mate with many males. This can be costly, but the benefits to females are often unclear. A new study raises the possibility that females could benefit through an unconventional genetic pathway, while also showing that males can inadvertently increase rival males' fitness in surprising ways

Evolution of Sexual Dimorphism and Male Dimorphism in the Expression of Beetle Horns: Phylogenetic Evidence for Modularity, Evolutionary Lability, and Constraint

Beetle horns are enlarged outgrowths of the head or thorax that are used as weapons in contests over access to mates. Horn development is typically confined to males (sexual dimorphism) and often only to the largest males (male dimorphism). Both types of dimorphism result from endocrine threshold mechanisms that coordinate cell proliferation near the end of the larval period. Here, we map the presence/absence of each type of dimorphism onto a recent phylogeny for the genus Onthophagits (Coleoptera: Scarabaeidae) to explore how horn development has changed over time. Our results provide empirical support for several recent predictions regarding the evolutionary lability of developmental thresholds, including uncoupled evolution of alternative phenotypes and repeated fixation of phenotypes. We also report striking evidence of a possible developmental constraint. We show that male dimorphism and sexual dimorphism map together on the phylogeny; whenever small males have horns, females also have horns (and vice versa). We raise the possibility that correlated evolution of these two phenomena results from a shared element in their endocrine regulatory mechanisms rather than a history of common selection pressures. These results illustrate the type of insight that can be gained only from the integration of developmental and evolutionary perspectives

HIV/AIDS Knowledge Sources of College Student-Athletes in a Southern State

This study examined the HIV/AIDS-related knowledge of 93 male and female college student-athletes at a DI institution in Louisiana. Knowledge levels are reported according to the ethnicity and gender of the respondents. Significant differences (p<.05) were found between ethnic groups for general knowledge about HIV/ AIDS and between genders for knowledge of disease transmissior methods and risk-reduction techniques. Survey participants indicated mass media, parents, and peers as the most common sources of HIV/AIDS information, and they preferred videos, small group discussions, and classroom lectures as instructional formats. Results may be useful in the development of more effective HIV/AIDS educational initiatives targeting college student-athletes

Population-Dynamics of Juvenile Caribbean Spiny Lobster, Panulirus-Argus, in Florida Bay, Florida

Despite a wealth of information on the growth and population dynamics of sub-adult and adult Caribbean spiny lobsters (Panulirus argus), there is far less information about younger juveniles under natural conditions. Here we describe growth and population dynamics of juvenile spiny lobsters (12-68 mm carapace length, CL) that we have studied for 14 months (October 1988-December 1989) using mark-recapture techniques in a hardbottom community in Florida Bay, Florida. We also monitored the supply of postlarvae into the region in 1988 and 1989 using Witham-type surface collectors in an effort to link peak periods of settlement of postlarvae with subsequent cohorts of juveniles. Field estimates of growth were the highest ever reported for this species, averaging 0.95 mm CL.wk-1 (range: 0.35-1.25 mm CL.wk-1 for individuals 20-25 mm CL and 40-45 mm CL, respectively). These results indicate that lobsters in some areas in Florida Bay can reach Florida\u27s legal harvestable size (76 mm CL) 1.5 years after settlement. Season and lobster size had significant effects on growth rates; slower growth occurred during the winter and among small individuals. Differences in growth among size classes resulted from changes in molt increment, whereas seasonal differences were a result of changes in intermolt interval. Using mark-recapture techniques, we estimate that the density of juvenile spiny lobsters \u3c45 mm CL in this prime nursery habitat was 454.ha-1, that the mean monthly probability of survival (reflecting actual mortality plus emigration) was 0.51, and that an average of 131 lobsters entered the population through recruitment and immigration each month. Recruitment of juveniles was significantly correlated (r = 0.83) with the supply of postlarvae to the region 8 months earlier. This relationship is stronger than was previously believed, and may only be manifested in areas with superior nursery habitat