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Anchorage, AK, United States

Alaska Pacific University is a small liberal arts college located in Anchorage, Alaska, that emphasizes experiential and active learning. The university is a member of the Eco League, a group of five small universities and colleges with strong programs in Psychology and Environmental Studies as well as related topics. Wikipedia.

Saenger C.,Alaska Pacific University | Wang Z.,Yale University
Quaternary Science Reviews | Year: 2014

Geochemical variations in marine biogenic carbonates that are preserved in the geological record serve as proxies of past environmental change. However, interpreting most proxies is complicated by biologically-mediated vital effects, highlighting the need to develop new tools for reconstructing paleoenvironmental change. Recently, magnesium (Mg) isotope variability in carbonates has been explored extensively to determine its utility as a paleoenvironmental proxy. We review the results of these works, which have yielded valuable information on the factors affecting Mg isotope fractionation between carbonates and solution (δ26Mgcarb-sol) in biogenic and abiogenic carbonate minerals. Strong evidence exists for a mineralogical control on δ26Mgcarb-sol, with the negative offset from 0‰ following the sequence aragonite~3mol/mol) and saturation states (Ω >~3) that are similar to seawater suggest that δ26Mgcarb-sol has a temperature dependence of ~0.01‰ °C-1 and is insensitive to precipitation rate. In contrast, a significant precipitation rate dependence is observed in calcites precipitated from solutions with relatively low Mg/Ca ratios (<~3mol/mol) and saturation states (Ω <~3). This difference likely reflects varying mineral growth mechanisms and we discuss the degree to which δ26Mgcarb-sol may be affected by factors such as fluid inclusions, amorphous calcium carbonate precursors, ion attachment/detachment kinetics, surface entrapment and Mg speciation. High-Mg calcite organisms, which likely precipitate from relatively unmodified seawater, also exhibit a temperature dependence of ~0.01‰ °C-1, albeit sometimes with a systematic offset toward smaller fractionations. In contrast, strong vital effects in low-Mg calcite organisms, which exclude Mg from their calcifying fluids, lead to δ26Mgcarb-sol values that exhibit no clear temperature dependence and are offset from abiogenic experiments. The majority of biogenic aragonites have δ26Mgcarb-sol values that are slightly more positive than those in abiogenic experiments, but bivalves and one sclerosponge species can exhibit significantly larger fractionations. Although vital effects and analytical uncertainties will limit δ26Mgcarb-sol paleotemperature reconstructions to anomalies of at least ±10°C, Mg isotope variability in biogenic carbonates may be a useful proxy for the Mg isotope composition of seawater, which reflects continental weathering, dolomitization and hydrothermal activity. © 2014 Elsevier Ltd. Source

Productivity linked to upwelling strength is an important environmental factor affecting the production and dynamics of octopus populations. This often takes the form of a negative relationship between octopus abundance and sea-surface temperatures (SST). Enteroctopus dofleini (giant Pacific octopuses) is caught as by-catch in several fisheries, but management for octopuses is data-poor. Visual surveys (in Prince William Sound (PWS) and Puget Sound) showed significant negative correlations of octopus counts with winter SST over the previous 30 months in the waters of eastern Gulf of Alaska, as expected on the basis of life-history parameters. In PWS, local octopus densities varied more than six-fold during the study, and correlations with SST accounted for 48-61% of the variance in counts. Octopus by-catch datasets were not similarly significantly correlated with SST. The negative correlation with SST suggests that octopus populations are influenced by factors regulating marine productivity during larval stages of life history far from the site of recruitment to benthic habitats. Targeted visual surveys for E. dofleini may be more predictable than by-catch statistics, and may be better estimators of variation in octopus abundance. © CSIRO 2015. Source

Agency: NSF | Branch: Continuing grant | Program: | Phase: ITEST | Award Amount: 1.36M | Year: 2014

This project expands, implements and conducts research on a previously developed framework for providing indigenous students with the workforce skills and knowledge needed for future Earth system science careers. The framework proven effective for Inupiat students during the NSF/ITEST-funded Arctic Climate Modeling Program (ESI-0525277) will be scaled up to develop culturally responsive STEM instruction for 1500 Yupik and Native Hawaiian middle school students and their 60 teachers. The multifaceted scale-up project includes: a broader research setting, more school districts, diverse indigenous cultures, additional STEM workforce practices, and a broader expert pool. The goal of the scale-up is to answer the research question, Under what circumstances are the PREPARES framework for offering culturally responsive STEM instruction effective in increasing indigenous student disposition toward participating in future Earth system science careers? Student objectives include assessing three indicators of student disposition toward STEM careers: (a) STEM academic achievement, (b) interest in STEM careers, and (c) STEM workforce skill readiness. Teacher objectives related to program sustainability include increasing educator STEM content knowledge and pedagogical strategies aligned with STEM workforce practices. Research by randomized controlled trial will determine framework transferability and identify circumstances and steps needed to expand its adoption to a broader array of U.S. schools.

This project is a professional development program for non-Native teachers of indigenous students. The project offers training that helps teachers provide culturally responsive science, technology, engineering and math (STEM) instruction in areas, such as Alaska and Hawaii, that support strong indigenous populations, but where the vast majority of teachers are non-Native. The research component will gather data and information that will advance the understanding of a framework for broadening indigenous participation in STEM study and careers. The activity targets middle school students because research indicates that middle school is a time when engagement in STEM studies begins to decline. Encouraging indigenous students to view completing high school as a step toward STEM careers is important because Native students compose a high percentage of the dropout population in Alaska and Hawaii. Culturally responsive STEM training is needed because many STEM teachers enter their preparation programs with little or no inter-cultural experience and with beliefs and assumptions that undermine the goal of providing an equal education for all students.

News Article
Site: http://phys.org/biology-news/

An octopus displays dark color and spread web and arms. Credit: David Scheel Octopuses have generally been viewed as solitary creatures—and their color-changing abilities primarily as a means to hide from hungry predators. But, after binge watching more than 52 hours of octopus TV, researchers reporting in the Cell Press journal Current Biology on January 28 have found that octopuses actually do have a social life. And it's not without drama. "We found that octopuses are using body patterns and postures to signal to each other during disputes," says David Scheel of Alaska Pacific University. "The postures and patterns can be quite flashy, such as standing very tall, raising the body mantle high above the eyes, and turning very dark." The octopuses in question belonged to a species known as Octopus tetricus living in the shallows of Jervis Bay, Australia. Scheel and his colleagues were tipped off that something interesting might be going on in that bay by a diver who alerted an online community of people interested in cephalopods that he'd seen something interesting. The researchers followed up from there, ultimately witnessing 186 octopus interactions and more than 500 actions. In all that video, the octopuses spent more than 7 hours interacting. Scheel along with colleagues at the University of Sydney noticed some intriguing patterns: when an octopus with a dark body color approached another dark octopus, the interaction was more likely to escalate to grappling. When a dark octopus approached a paler one, the pastier octopus more often retreated. When the opposite happened and a light octopus approached a darker one, the latter more often stood its ground. "Dark color appears to be associated with aggression, while paler colors accompany retreat," Scheel says. Octopuses also displayed on high ground, standing with their web spread and their mantle elevated. Octopuses in that "stand tall" posture frequently also sought higher ground. The researchers suspect the octopuses' behaviors are meant to make themselves appear larger and more conspicuous. The findings expand scientists' understanding of how octopuses interact and communicate with each other. The researchers now suspect that social interactions among octopuses are likely to occur wherever food is plentiful and hiding places are scarce. They'll continue to study these octopuses and to explore how their social lives might influence the size of the population. More information: Current Biology, Scheel et al.: "Signal Use by Octopuses in Agonistic Interactions" dx.doi.org/10.1016/j.cub.2015.12.033

News Article
Site: http://www.nature.com/nature/current_issue/

Octopuses use body colour and posture to communicate to others during aggressive encounters, suggesting that they are more social than previously thought. Octopuses are considered to be more solitary animals than many squid or cuttlefish. David Scheel of Alaska Pacific University in Anchorage and his colleagues reviewed filmed interactions between pairs of Octopus tetricus off the coast of New South Wales, Australia. Octopuses were darker when they were about to fight an approaching animal and paler when they were set to flee. When dark in colour, the animals also changed their posture — by standing tall on higher ground and spreading the webs between their arms. The octopuses could be using these signals to communicate their size, strength and willingness to fight to a rival, the authors say.

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