Influence of polarized light, disruptive visual patterns, and chemical cues on oviposition in the aquatic midge, Chironomus riparius (Diptera: Chironomidae).

Chironomid nonbiting midges are common in many waterbodies, occurring at high densities in sediment and also when flying adults emerge. Although important for food webs and ecosystem processes, the mass emergences of chironomid adults make some species nuisance pests. As part of an effort to develop "push-pull" strategies for managing midge populations, we investigated the importance of visual and chemical cues used by gravid females when selecting sites for oviposition. Field and laboratory oviposition choice tests with Chironomus riparius (Meigen) were used to assess the attractiveness of dark container colors and polarized light for females seeking water for egg laying. Females were not sensitive to increased intensity of polarized light, but they laid fewer eggs in containers with white color above the water's edge but black below the surface. A disruptive pattern of vertical black and white stripes at the water's edge reduced egg laying to a similar degree as white. To investigate the importance of olfactory or gustatory cues in oviposition decisions, we tested 3 potential chemical repellents (damaged larvae simulating predator presence, azadiractin, and picaridin) and 5 potential attractants (a tannin-molasses mixture, leaf detritus, live Hydrilla plants, periphyton, and fermented alfalfa infusions used to bait mosquito oviposition traps). Chemical cues appeared to play a weak role, if any, in oviposition choices. Onlyazadiractin (0.02 and 0.11 ppm) reduced the number of egg ropes deposited, but the mechanism may have been from mechanical trapping and drowning, not deterrence.

Nurse Practitioner's Confidence and Competence of Advance Directives: The Benefits of an Educational Program.

The increase in the number of people developing dementia, the growing number of geriatric patients suffering and dying from serious chronic diseases, and the rising costs of health care as a result of an aging population have centered attention on advance care planning. Advance care planning is the recurrent conversation between competent patients, their families, and the health care provider about end of life care. Although vital, advance care planning discussions between providers and patients are not occurring regularly, and completion rates of advance directives are low. Barriers to health care providers discussing advance directives include lack of time, knowledge, and confidence. The purpose of this project was to evaluate the effectiveness of an educational program regarding advance directives on nurse practitioner's competency and confidence to start advance care planning discussions. Wilcoxon signed rank test indicated that post-education, confidence improved significantly for all items (average rank of 4.5 vs average rank of 10.65). The study showed that most of the nurse practitioners were knowledgeable about advance directives and the educational program increased their level of confidence about initiating advance directive discussions.

Addressing the Lack of Professional Values and Behaviors among New Nurses.

Professionalism and safety in patient care are concepts nurses are expected to exhibit in practice. High fidelity simulation was explored to assist in teaching students the behaviors needed to succeed in nursing. Nursing leaders identified areas in which graduates struggle, including critical thinking, skills acquisition, time management, role responsibilities, delegation, and effective communication. The project's purpose was to analyze students' perceptions regarding professional nursing values, identify gaps in knowledge concerning professional behavior, and determine perception change of professional values. A pretest post-test simulation intervention was chosen. Improvement in communication and autonomy was noted with statistically significant findings.

Predicting mayfly recovery in acid mine-impaired streams using logistic regression models of in-stream habitat and water chemistry.

Mayflies (Order Ephemeroptera) require high quality water and habitat in streams to thrive, so their appearance after restoration is an indicator of ecological recovery. To better understand the importance of restoring in-stream habitat versus water chemistry for macroinvertebrate communities, we developed taxon-specific models of occurrence for five mayfly genera (Caenis, Isonychia, Stenonema, Stenacron, and Baetis) inhabiting streams in the Appalachian Mountains, USA. Presence/absence records from past decades were used to develop single and multiple logistic predictive models based on catchment characteristics (drainage area, gradient), in-stream habitat variables (e.g., substrate, channel morphology, pool and riffle quality), and water chemistry. Model performance was evaluated using (a) classification rates and Hosmer-Lemeshow values for test sets of data withheld from the original model-building dataset and (b) a field comparison of predicted versus observed mayfly occurrences at 53 sites in acid mine drainage-impaired watersheds in 2012. The classification accuracies of final models for Caenis, Stenacron, and Baetis ranged from 50 to 75%. In-stream habitat features were not significant predictor variables for these three taxa, only water chemistry. Models for Isonychia and Stenonema had higher classification rates (81%) and included both habitat and chemical variables. However, actual occurrences of Isonychia and Stenonema at study sites in 2012 were low, consistent with the calculated probability of occurrence (Po) < 0.60. Caenis occurred at test sites 35% of the time when the model predicted a Po > 0.40. Stenacron showed the greatest consistency of actual versus predicted occurrences, occurring at 56% of sites when the Po (based on pH and conductivity) was > 0.50 and only at 1 site when Po < 0.5. The results demonstrate how predictive models of individual indicator taxa could be valuable for evaluating the relative impacts of restoring physical habitat versus water chemistry during stream remediation.

Use of leaf litter breakdown and macroinvertebrates to evaluate gradient of recovery in an acid mine impacted stream remediated with an active alkaline doser.

The spatial congruence of chemical and biological recovery along an 18-km acid mine impaired stream was examined to evaluate the efficacy of treatment with an alkaline doser. Two methods were used to evaluate biological recovery: the biological structure of the benthic macroinvertebrate community and several ecosystem processing measures (leaf litter breakdown, microbial respiration rates) along the gradient of improved water chemistry. We found that the doser successfully reduced the acidity and lowered dissolved metals (Al, Fe, and Mn), but downstream improvements were not linear. Water chemistry was more variable, and precipitated metals were elevated in a 3-5-km "mixing zone" immediately downstream of the doser, then stabilized into a "recovery zone" 10-18 km below the doser. Macroinvertebrate communities exhibited a longitudinal pattern of recovery, but it did not exactly match the water chemistry gradient Taxonomic richness (number of families) recovered about 6.5 km downstream of the doser, while total abundance and % EPT taxa recovery were incomplete except at the most downstream site, 18 km away. The functional measures of ecosystem processes (leaf litter breakdown, microbial respiration of conditioned leaves, and shredder biomass) closely matched the measures of community structure and also showed a more modest longitudinal trend of biological recovery than expected based on pH and alkalinity. The measures of microbial respiration had added diagnostic value and indicated that biological recovery downstream of the doser is limited by factors other than habitat and acidity/alkalinity, perhaps episodes of AMD and/or impaired energy/nutrient inputs. A better understanding of the factors that govern spatial and temporal variations in acid mine contaminants, especially episodic events, will improve our ability to predict biological recovery after remediation.

Plant phenolics behave as radical scavengers in the context of insect (Manduca sexta) hemolymph and midgut fluid.

To evaluate the prooxidant versus antioxidant properties of plant phenolics toward leaf-feeding caterpillars, quenching of the stable ABTS radical by five phenolics was measured in two physiological contexts: hemolymph and midgut fluid. Addition of tannic acid, chlorogenic acid, quercetin, or catechin to Manduca sexta (L.) gut fluid increased its total antioxidant capacity by 12-45%, with tannic acid and quercetin being the most powerful in this regard. The antioxidant contribution of the phenolics increased with longer (30-60 min) incubation time in gut fluid. Chlorogenic acid and caffeic acid exhibited the weakest antioxidant activity in gut fluid. The total antioxidant capacity of hemolymph is considerably less than that of gut fluid, and in hemolymph chlorogenic and caffeic acids sometimes acted as mild prooxidants, particularly after longer incubation periods (30-60 min), although this trend was not statistically significant. Tannic acid, catechin, and quercetin behaved as antioxidants in hemolymph. These results suggest that many phenolics have radical scavenging activity in the digestive tract, but some may have more detrimental effects after absorption into the hemolymph compartment.

Temporal modulation of pyrrolizidine alkaloid intake and genetic variation in performance of Utetheisa ornatrix caterpillars.

Foraging on a variety of different food items allows individuals to balance nutrient intake, but it also may dilute toxins present in single items of the diet. The distinction between nutrient balancing and toxin dilution becomes less clear, however, for organisms that sequester potentially toxic compounds for their own benefit. Additionally, specific dietary components chosen may or may not affect metabolic rate, growth, and other measures of fitness. Using the arctiid moth Utetheisa ornatrix, we (1) evaluated the temporal pattem of larval feeding behavior when presented with diet enriched with the pyrrolizidine alkaloid (PA), monocrotaline, (2) estimated the cost of ingesting PAs by measuring larval nutritional performance on diets containing different amounts of usaramine, and (3) investigated the magnitude of genetic effects on the performance of families raised on diets of different usaramine concentrations. We demonstrate that an herbivorous insect can temporally vary its intake of sequestered allelochemical. Individuals combined a preference for intermediate amounts of monocrotaline with temporal modulation of the specific amount of PA ingested on a given day. Using usaramine, we found little evidence for a cost of ingesting PAs, except among some family groups. Measures of digestive and metabolic efficiency showed no consistent reduction in performance on higher alkaloid diets. Only when larvae in family groups were fed a single concentration of PA over more than one instar was there any evidence for a cost of ingestion. Additionally, there were large genetic components to both growth and an individual's growth response to dietary alkaloid. These results suggest that while genetic variation in performance on alkaloid-rich diets exists, modulation of intake rate by caterpillars may be an important mechanism to reduce effects on the growth and fitness of individuals.