Implications on distribution and abundance of benthic macroinvertebrates in the Maple River based on water quality and habitat type.

General Ecology (spring term)Macroinvertebrate communities are often diverse and variable in richness and abundance depending on water quality in aquatic ecosystems. Measures of water quality (e.g. alkalinity, pH, conductivity, salinity, macronutrient content) and habitat forms can vary in different locations and affect the abundance of macroinvertebrates there. Riffles (flowing water) and pools (standing water) form in streams and provide different habitats for macroinvertebrates. To test the effects water quality and habitat have on macroinvertebrate richness and abundance, three sites along the Maple River in Pellston, MI were sampled. In respect to water quality, we observed large differences between the East and West Branch locations, mainly involving higher levels of nitrate, total nitrogen, and conductivity from the West Branch located downstream from the Pellston Airport and multiple farming areas. Along with testing water quality at each site, macroinvertebrates distribution and diversity was analyzed to show a decrease in diversity among the West Branch as compared to the East Branch. Our findings suggest that pollution from anthropogenic sources impacts water quality of nearby streams and rivers, resulting in the decrease of macroinvertebrate diversity.http://deepblue.lib.umich.edu/bitstream/2027.42/116397/1/Griffiin_Myers_Sloan_2015.pd

Exploring pedagogical culture for accessibility education in Computing Science

This paper identifies some of the challenges of teaching and learning accessibility through the lens of pedagogy (which deals with the theory and practice of education). We argue that accessibility education in computing science presents a set of unique and challenging characteristics for those engaged in accessibility capacity building. Significant moves are being made to embed accessibility within academic curricula and professional domains. However, through a qualitative thematic review of the accessibility pedagogic literature, we find that the field lacks the pedagogic culture necessary to support widespread excellence in teaching and learning. Nonetheless, our review identifies aspects of this small but important literature that indicate how a pedagogic culture for accessibility can be stimulated through research, debate and discussion, to promote a more pedagogically-grounded approach to the field as a whole

Predoctoral Interns\u27 Nondisclosure in Supervision

In interviews with 14 counseling center predoctoral interns regarding a significant nondisclosure in supervision, eight interns reported good supervisory relationships and six indicated that they experienced problematic supervisory relationships. Nondisclosures for the interns in good supervisory relationships related to personal reactions to clients, whereas nondisclosures for interns in problematic supervisory relationships related to global dissatisfaction with the supervisory relationship. In both groups, interns mentioned concerns about evaluation and negative feelings as typical reasons for nondisclosure. Additional reasons for nondisclosure for interns in problematic supervision were power dynamics, inhibiting demographic or cultural variables, and the supervisor\u27s theoretical orientation. Both groups described negative effects of nondisclosure on themselves and their relationships with clients. Interns in problematic supervision also reported that nondisclosures had negative effects on the supervisory relationship

Forest ecosystem-service transitions: the ecological dimensions of the forest transition

New forests are expanding around the world. In many regions, regrowth rates are surpassing deforestation rates, resulting in "forest transitions," or net gains in forest cover. Typically measured only in terms of aggregate "forest cover" change, these new forests are ecologically distinct from each other and from those originally cleared. We ask, what are the ecological attributes, goods, and services we might expect from different pathways of forest recovery? To address this question, we proposed a typology of forest transitions that reflects both their social drivers and ecological outcomes: tree plantation, spontaneous regeneration, and agroforestry transitions. Using case studies, we illustrate how the ecological outcomes of each transition type differ and change over time. We mapped the global distribution of forest-transition types to identify global epicenters of each, and found that spontaneous transitions are most common globally, especially in Latin America; agroforestry transitions predominate in Europe and Central America; and plantation transitions occur in parts of Europe and Asia. We proposed a conceptual framework to understand and compare the ecological services arising from different types of forest transitions over time: forest ecosystem-service transition curves. This framework illustrates that carbon sequestration tends to be comparatively lower in agroforestry transitions, and biodiversity recovery is lower in industrial plantations. Spontaneously regenerating forests tend to have relatively high biodiversity and biomass but provide fewer provisioning and economically valuable services. This framework captures the dynamism that we observe in forest transitions, thus illustrating that different social drivers produce different types of ecosystem-service transitions, and that as secondary forests grow, these services will change over time at rates that differ among transition types. Ultimately, this framework can guide future research, describe actual and potential changes in ecosystem services associated with different types of transitions, and promote management plans that incorporate forest cover changes with the services and benefits they provide

Growth factor liberation and DPSCs response following dentine conditioning

Liberation of the sequestrated bioactive molecules from dentine by the action of applied dental materials has been proposed as an important mechanism in inducing a dentinogenic response in teeth with viable pulps. Although adhesive restorations and dentine-bonding procedures are routinely practiced, clinical protocols to improve pulp protection and dentine regeneration are not currently driven by biological knowledge. This study investigated the effect of dentine (powder and slice) conditioning by etchants/conditioners relevant to adhesive restorative systems on growth factor solubilization and odontoblast-like cell differentiation of human dental pulp progenitor cells (DPSCs). The agents included ethylenediaminetetraacetic acid (EDTA; 10%, pH 7.2), phosphoric acid (37%, pH <1), citric acid (10%, pH 1.5), and polyacrylic acid (25%, pH 3.9). Growth factors were detected in dentine matrix extracts drawn by EDTA, phosphoric acid, and citric acid from powdered dentine. The dentine matrix extracts were shown to be bioactive, capable of stimulating odontogenic/osteogenic differentiation as observed by gene expression and phenotypic changes in DPSCs cultured in monolayer on plastic. Polyacrylic acid failed to solubilize proteins from powdered dentine and was therefore considered ineffective in triggering a growth factor–mediated response in cells. The study went on to investigate the effect of conditioning dentine slices on growth factor liberation and DPSC behavior. Conditioning by EDTA, phosphoric acid, and citric acid exposed growth factors on dentine and triggered an upregulation in genes associated with mineralized differentiation, osteopontin, and alkaline phosphatase in DPSCs cultured on dentine. The cells demonstrated odontoblast-like appearances with elongated bodies and long extracellular processes extending on dentine surface. However, phosphoric acid–treated dentine appeared strikingly less populated with cells, suggesting a detrimental impact on cell attachment and growth when conditioning by this agent. These findings take crucial steps in informing clinical practice on dentine-conditioning protocols as far as treatment of operatively exposed dentine in teeth with vital pulps is concerned