914 research outputs found
Sister Act: Margaret Walker and Eudora Welty
At the end of their lives, in the 1980s and ’90s, both Margaret Walker and Eudora Welty were recognized several times by their hometown and state for their long careers and bodies of work. The paths they traveled to reach this intersection of common recognition were quite different, however. Almost exact contemporaries -— Welty lived from 1909-2001 and Walker from 1915-1998 -— they share similar timelines and histories, both having lived through the Depression, World War II, and the civil rights movement. But as one was white and one was black, their stories are very different, as are their paths to becoming nationally known writers.https://egrove.olemiss.edu/studythesouth/1022/thumbnail.jp
Distribution of Fish Within Headwater Riffles of the Illinois River System, Washington County, Arkansas
Quantitative sampling of fish was performed in five headwater riffles of the Illinois River System, Washington County, Arkansas during low flow conditions. This study revealed differing fish species composition, biomass and feeding guild segregation between head and tail riffle reaches in 1st through 3rd order. Thirty species representing 10 families were identified. Of this number, darters (Percidae), sculpins (Cottidae), madtoms (Ictaluridae), and central stonerollers (Campostoma anomalum) (Cyprinidae) comprised 67 to 98 percent of riffle head populations. Fish biomass was greater for riffle head areas (0.58-6.6/0.28-2.0 g/m2 ) within sectivores and herbivores dominating. Total fish numbers decreased from riffleheads to tails, while number of species increased. Dominant fish groups in tail areas were minnows (Cyprinidae), darters (Percidae), and sunfishes (Centrarchidae). Feeding guild fish groups in tail areas were predominately insectivore and insectivore-piscivore. Stomach analysis of Cottus carolinae, the dominant headwater riffle predator, indicated selective feeding of macrobenthic invertebrates and fish based on size class. Abundance of herbivore and insectivore fishes in riffles, particularly head reaches, suggests a correlation with positive rheotaxic behavior, microhabitat preference or abundance of macrobenthic invertebrate populations
Course/instructor evaluation : perspectives of part-time graduate students
This study explored 6 part-time graduate students' perspectives on
course/instructor evaluation. The purpose was to explore whether a link exists
between the evaluation for course and instructors as contained in the Faculty of
Education courselinstructor evaluation form and the needs of part-time students
enrolled in that program. The literature review provided contextual information
concerning the 3 main subject areas based upon which the research questions
were designed: learner needs in the context of part-time graduate students,
courselinstructor eval~ation, and the potential lack of congruency between the 2.
Using a semistructured interview process, participants identified criteria important
or relevant to the evaluation process and incongruent with the course/instructor
evaluation form. A qualitative research methodology using a grounded theory
approach contributed to the theory on the nature of course evaluation instruments
in a graduate program and addressed the notion of where power was situated
within the evaluation process.
Findings suggested that the concepts of relevance and the instructor's role
that participants identified as important in their graduate learning experience were
congruent with what they considered important components of the
course/instructor evaluation form. Participants noted a lack of congruency
between their expectations of a quality graduate learning experience and the
format, content, intent, and timing of the evaluation process. The study confirmed
that students did want a voice in the evaluation of their learning experience at
both the course and program levels
INCORPORATING EFFECTS-BASED APPROACHES INTO ENVIRONMENTAL IMPACT ASSESSMENT TO IMPROVE POST-DEVELOPMENT MONITORING
Over the last 50 years, improvements in design of industrial facilities have significantly reduced environmental impacts. But impacts still occur and monitoring programs are the main mechanism to inform when modification/implementation of mitigation is needed. Informed decisions require adequate baseline (pre-development) data to predict impacts based on the development’s design and to understand when the post-development environment has changed. An adaptive monitoring plan provides an effective way to evaluate monitoring results and allow for proactive responses to environmental change before impacts become difficult or challenging to reverse. Unfortunately, baseline data gathered during an environmental impact assessment (EIA) is often inadequate to support an effective post-development adaptive monitoring plan. The primary objective of this dissertation was to demonstrate how post-development monitoring can be improved through forethought during the baseline and predictive assessment phases of an EIA.
Interpreting the key ecosystem attributes through a lens of ecosystem services that fish require defines measurable attributes that should form key components of pre-development and post-development evaluation and can aid in developing consistency across the phases of an EIA. A review of Canadian hydroelectric facility EIAs concluded that adaptive management would be improved if EIAs do more quantitative modeling that links to adaptive monitoring plans based on better pre-development baselines. A case study evaluated how fish surveys could be used to develop thresholds and decision points and concluded that more than four years of data are needed to develop sensitive monitoring and forecast triggers. Consistent times and locations are required for both adult and young-of-the-year sampling to ensure that data can be compared between years.
Practitioners should consider what is needed for an effective assessment and post-development adaptive monitoring plan early in the EIA process (i.e., before project specific baseline data collection starts) to ensure there is enough data to calculate quantitative models to estimate impacts and to be able to determine when post-development change has occurred. If we don’t have the proper information to evaluate if there is an impact and to define the cause, then monitoring has failed. Improvement of EIA and post-development monitoring will better focus environmental protection and adaptive management
Fish communities near municipal wastewater discharges in the Grand River watershed
Municipal wastewater effluent (MWWE) has the potential for aquatic degradation, as it is the largest, per volume, anthropogenic discharge in Canada and other areas in the world. With an increasing population in many areas, such as Southern Ontario, there is concern that infrastructure of wastewater treatment facilities will not be able to maintain adequate treatment and prevent further degradation of the environment. The Grand River watershed, in Southern Ontario, is predicted to have its population increase to 1.2 million people by 2031 (from 780,000 people in 2001). Although wastewater treatment has improved, concern remains for receiving environments due to inadequate treatment (i.e. Kitchener) and minimal dilution (i.e. Guelph). This research was conducted to understand current impacts of MWWE in the Grand River watershed on fish communities to support future management and protection. Study sites upstream and downstream were chosen for their proximity to the Guelph, Kitchener, and Waterloo MWWE outfalls, similarity in habitat, and wadeability. Habitat analysis indicated that there were no large physical differences among sites. Fish communities were collected in a standardized method with a backpack electroshocker at each site (six randomly selected 10 m by 10 m sub-sites for 5 min). Greenside Darter (Etheostoma blennioides) and Rainbow Darter (E. caeruleum), the most abundant species, were also analyzed for stable isotope signatures (δ13C and δ15N) at each site. Downstream of the Guelph outfall there were no changes in mean total catch per unit effort (CPUE) or mean total mass. Changes to diversity, resilience, and tolerance in the fish community were attributed to a decreased abundance of Greenside Darter and increased abundance of Rainbow Darter. Downstream of the Kitchener discharge, there was a trend towards decreasing mean total CPUE, especially for darter species, and an increase in mean total mass due to a community shift to larger species including Catostomids and Centrarchids. The changes in abundance of Rainbow Darter, Catostomids, and Centrarchids among reference and Kitchener MWWE exposed sites explained the pattern in resilience, tolerance, and diet classifications. Lower diversity downstream of all three MWWE outfalls can be attributed to the increase in Rainbow Darter abundance. Stable isotope signatures (δ13C and δ15N) of Greenside Darter did not change downstream of the Guelph and Waterloo discharges, but signatures of Rainbow Darter increased immediately below the two outfalls. This shift may be due to the Rainbow Darter being able to take advantage of a change in the environment (i.e. food availability), resulting in its increased abundance and changes in isotopic signature. Directly downstream of the Kitchener outfall both darter species had an increase in δ13C and a large decrease in δ15N, likely due to high nutrient inputs from the outfall. The Kitchener wastewater discharge is also associated with a decrease in abundance of fish and a shift in community structure. MWWEs are currently affecting the aquatic environment, including fish communities in the Grand River watershed. Future investments in infrastructure and watershed management should be made to mitigate degradation of water quality in this watershed
Stabilization and Localization of Xist RNA are Controlled by Separate Mechanisms and are Not Sufficient for X Inactivation
These studies address whether XIST RNA is properly localized to the X chromosome in somatic cells where human XIST expression is reactivated, but fails to result in X inactivation (Tinker, A.V., and C.J. Brown. 1998. Nucl. Acids Res. 26:2935–2940). Despite a nuclear RNA accumulation of normal abundance and stability, XIST RNA does not localize in reactivants or in naturally inactive human X chromosomes in mouse/ human hybrid cells. The XIST transcripts are fully stabilized despite their inability to localize, and hence XIST RNA localization can be uncoupled from stabilization, indicating that these are separate steps controlled by distinct mechanisms. Mouse Xist RNA tightly localized to an active X chromosome, demonstrating for the first time that the active X chromosome in somatic cells is competent to associate with Xist RNA. These results imply that species-specific factors, present even in mature, somatic cells that do not normally express Xist, are necessary for localization. When Xist RNA is properly localized to an active mouse X chromosome, X inactivation does not result. Therefore, there is not a strict correlation between Xist localization and chromatin inactivation. Moreover, expression, stabilization, and localization of Xist RNA are not sufficient for X inactivation. We hypothesize that chromosomal association of XIST RNA may initiate subsequent developmental events required to enact transcriptional silencing
Effects of Stimulation Level and Electrode Pairing on the Binaural Interaction Component of the Electrically Evoked Auditory Brain Stem Response
The purpose of this study was to investigate the effects of stimulation level and electrode pairing on the binaural interaction component (BIC) of the electrically evoked auditory brain stem response (EABR) in Nucleus cochlear implant users
Effectiveness of a Peer-Delivered Dissonance-Based Program in Reducing Eating Disorder Risk Factors in High School Girls
Objective
This pilot study investigated the feasibility, acceptability, and effectiveness of a peer-led dissonance-based eating disorders (ED) prevention/risk factor reduction program with high school girls. Method
Ninth grade girls (n  = 50) received the peer-led program within the school curriculum. A quasi-experimental design was used to assess changes in ED risk factors preintervention and postintervention compared with waitlist control. Participants were followed through 3-month follow-up. Results
Peer-leader adherence to an intervention manual tailored for this age group was high. The intervention was rated as highly acceptable, with a large proportion of participants reporting that they enjoyed the program and learned and applied new information. Intervention participants exhibited significantly greater pre-post reductions in a majority of risk-factor outcomes compared to waitlist controls. When groups were combined to assess program effects over time there were significant pre-post reductions in a majority of outcomes that were sustained through 3-month follow-up. Discussion
This pilot study provides tentative support for the effectiveness of using peer leaders to implement an empirically supported ED risk factor reduction program in a high school setting. Additional research is needed to replicate results in larger, better-controlled trials with longer follow-up
Preliminary Results of the Relationship Between the Binaural Interaction Component of the Electrically Evoked Auditory Brainstem Response and Interaural Pitch Comparisons in Bilateral Cochlear Implant Recipients
The purpose of this study was to investigate the relationship between electrophysiologic measures of the binaural interaction component (BIC) of the electrically evoked auditory brainstem response (EABR) and psychophysical measures of interaural pitch comparisons in Nucleus bilateral cochlear implant users
Exploring the evidence base for Tier 3 specialist weight management interventions for children aged 2–18 years in the UK: a rapid systematic review
Background: The impact of specialist weight management services (Tier 3) for children with severe and complex obesity in the UK is unclear. This review aims to examine the impact of child Tier 3 services in the UK, exploring service characteristics and implications for practice. Methods: Rapid systematic review of any study examining specialist weight management interventions in any UK setting including children (2–18 years) with a body mass index >99.6th centile or >98th centile with comorbidity. Results: Twelve studies (five RCTs and seven uncontrolled) were included in a variety of settings. Study quality was moderate or low and mean baseline body mass index z-score ranged from 2.7 to 3.6 units. Study samples were small and children were predominantly older (10–14 years), female and white. Multidisciplinary team composition and eligibility criteria varied; dropout ranged from 5 to 43%. Improvements in zBMI over 1–24 months ranged from −0.13 to −0.41 units. Conclusions: Specialist weight management interventions for children with severe obesity demonstrated a reduction in zBMI, across a variety of UK settings. Studies were heterogeneous in content and thus conclusions on service design cannot be drawn. There is a paucity of evidence for Tier 3 services for children, and further research is required
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