Foraging Economics of the Hunt Bumble Bee, a Viable Pollinator for Commercial Agriculture

Globally, there are only five bumble bee (Hymenoptera: Apidae, Bombus) species that have been successfully commercialized for agriculture. The Hunt bumble bee, Bombus huntii Green, 1860, has been recognized as a suitable pollinator of crops and has a broad distribution in western North America, making it a viable candidate for commercialization. In this study, our goal was to characterize the foraging dynamics of B. huntii female workers under open field conditions. To accomplish this goal, we monitored three B. huntii colonies over an 8-wk period in the summer of 2012 in northern Utah. Using marked bees, we studied the relationship between foraging duration/offloading and pollen/nonvisible pollen collection. In total, we observed 921 foraging events across all three colonies. Of our observations, 82% (n = 756) were foraging events that included both a departure and arrival time observation. Average duration of pollen and nonpollen (i.e., nectar) trips across foragers is 41.86 ± 5.65 min (±SE) and 32.18 ± 5.89 min, respectively. Workers spent a significantly longer time offloading pollen in the nest after a foraging trip relative to workers without pollen present on their corbicula. Pollen foraging rate increases over the course of the day, likely due to the time it takes to learn how to forage on a diverse array of flower morphologies. Our study provides data on how long it takes for B. huntii to forage in open field conditions and will be useful when comparing foraging rates in controlled crop systems

An In Vitro Comparative Study of Intracanal Fluid Motion and Wall Shear Stress Induced by Ultrasonic and Polymer Rotary Finishing Files in a Simulated Root Canal Model

Objective. This in vitro study compared the flow pattern and shear stress of an irrigant induced by ultrasonic and polymer rotary finishing file activation in an acrylic root canal model. Flow visualization analysis was performed using an acrylic canal filled with a mixture of distilled water and rheoscopic fluid. The ultrasonic and polymer rotary finishing file were separately tested in the canal and activated in a static position and in a cyclical axial motion (up and down). Particle movement in the fluid was captured using a high-speed digital camera and DaVis 7.1 software. The fluid shear stress analysis was performed using hot film anemometry. A hot-wire was placed in an acrylic root canal and the canal was filled with distilled water. The ultrasonic and polymer rotary finishing files were separately tested in a static position and in a cyclical axial motion. Positive needle irrigation was also tested separately for fluid shear stress. The induced wall shear stress was measured using LabVIEW 8.0 software

Construction and Nursing Students, Building a Playground for Bauer Family Services

Poster Sessio

Estrogen-Like Activity of Perfluoroalkyl Acids In Vivo and Interaction with Human and Rainbow Trout Estrogen Receptors In Vitro

The objectives of this study were to determine the structural characteristics of perfluoroalkyl acids (PFAAs) that confer estrogen-like activity in vivo using juvenile rainbow trout (Oncorhynchus mykiss) as an animal model and to determine whether these chemicals interact directly with the estrogen receptor (ER) using in vitro and in silico species comparison approaches. Perfluorooctanoic (PFOA), perfluorononanoic (PFNA), perfluorodecanoic (PFDA), and perfluoroundecanoic (PFUnDA) acids were all potent inducers of the estrogen-responsive biomarker protein vitellogenin (Vtg) in vivo, although at fairly high dietary exposures. A structure-activity relationship for PFAAs was observed, where eight to ten fluorinated carbons and a carboxylic acid end group were optimal for maximal Vtg induction. These in vivo findings were corroborated by in vitro mechanistic assays for trout and human ER. All PFAAs tested weakly bound to trout liver ER with half maximal inhibitory concentration (IC50) values of 15.2-289μM. Additionally, PFOA, PFNA, PFDA, PFUnDA, and perlfuorooctane sulfonate (PFOS) significantly enhanced human ERα-dependent transcriptional activation at concentrations ranging from 10-1000nM. Finally, we employed an in silico computational model based upon the crystal structure for the human ERα ligand-binding domain complexed with E2 to structurally investigate binding of these putative ligands to human, mouse, and trout ERα. PFOA, PFNA, PFDA, and PFOS all efficiently docked with ERα from different species and formed a hydrogen bond at residue Arg394/398/407 (human/mouse/trout) in a manner similar to the environmental estrogens bisphenol A and nonylphenol. Overall, these data support the contention that several PFAAs are weak environmental xenoestrogens of potential concer

The effect of midwifery care on rates of cesarean delivery

Objective: To examine whether changing to a midwifery-led maternity service model was associated with a lower national rate of cesarean delivery. Methods: We analyzed trends in the rate of cesarean delivery per 1000 live births between 1996 and 2010 in New Zealand. Estimates of relative increases in rate were calculated via Poisson regression for several maternal age groups over the study period. Results: Rates of cesarean delivery increased over the study period, from 156.9 per 1000 live births in 1996 to 235 per 1000 in 2010: a crude increase of 49.8%. Increasing trends were apparent in each age group, with the largest increases occurring before 2003 and relatively stable rates in the subsequent period. The smoothed estimate showed that the increase in cesarean rate across all age groups was 43.7% (95% confidence interval, 41.6–45.8) over the 15-year period. Conclusion: A national midwifery-led care model was not associated with a decreased rate of cesarean delivery but, instead, with an increase similar to that in other high-resource countries. This indicates that other factors may account for the increase. Further research is needed to examine maternity outcomes associated with different models of maternity care

Inclusion, Analysis, and Reporting of Sex and Race/Ethnicity in Clinical Trials: Have We Made Progress?

Background: The National Institutes of Health (NIH) Revitalization Act of 1993 requires that NIH-funded clinical trials include women and minorities as participants; other federal agencies have adopted similar guidelines. The objective of this study is to determine the current level of compliance with these guidelines for the inclusion, analysis, and reporting of sex and race/ethnicity in federally funded randomized controlled trials (RCTs) and to compare the current level of compliance with that from 2004, which was reported previously. Methods: RCTs published in nine prominent medical journals in 2009 were identified by PubMed search. Studies where individuals were not the unit of analysis, those begun before 1994, and those not receiving federal funding were excluded. PubMed search located 512 published articles. After exclusion of ineligible articles, 86 (17%) remained for analysis. Results: Thirty studies were sex specific. The median enrollment of women in the 56 studies that included both men and women was 37%. Seventy-five percent of the studies did not report any outcomes by sex, including 9 studies reporting <20% women enrolled. Among all 86 studies, 21% did not report sample sizes by racial and ethnic groups, and 64% did not provide any analysis by racial or ethnic groups. Only 3 studies indicated that the generalizability of their results may be limited by lack of diversity among those studied. There were no statistically significant changes in inclusion or reporting of sex or race/ethnicity when compared with 2004. Conclusions: Ensuring enhanced inclusion, analysis, and reporting of sex and race/ethnicity entails the efforts of NIH, journal editors, and the researchers themselves

Estrogen-Like Activity of Perfluoroalkyl Acids In Vivo and Interaction with Human and Rainbow Trout Estrogen Receptors In Vitro

The objectives of this study were to determine the structural characteristics of perfluoroalkyl acids (PFAAs) that confer estrogen-like activity in vivo using juvenile rainbow trout (Oncorhynchus mykiss) as an animal model and to determine whether these chemicals interact directly with the estrogen receptor (ER) using in vitro and in silico species comparison approaches. Perfluorooctanoic (PFOA), perfluorononanoic (PFNA), perfluorodecanoic (PFDA), and perfluoroundecanoic (PFUnDA) acids were all potent inducers of the estrogen-responsive biomarker protein vitellogenin (Vtg) in vivo, although at fairly high dietary exposures. A structure-activity relationship for PFAAs was observed, where eight to ten fluorinated carbons and a carboxylic acid end group were optimal for maximal Vtg induction. These in vivo findings were corroborated by in vitro mechanistic assays for trout and human ER. All PFAAs tested weakly bound to trout liver ER with half maximal inhibitory concentration (IC50) values of 15.2–289μM. Additionally, PFOA, PFNA, PFDA, PFUnDA, and perlfuorooctane sulfonate (PFOS) significantly enhanced human ERα-dependent transcriptional activation at concentrations ranging from 10–1000nM. Finally, we employed an in silico computational model based upon the crystal structure for the human ERα ligand-binding domain complexed with E2 to structurally investigate binding of these putative ligands to human, mouse, and trout ERα. PFOA, PFNA, PFDA, and PFOS all efficiently docked with ERα from different species and formed a hydrogen bond at residue Arg394/398/407 (human/mouse/trout) in a manner similar to the environmental estrogens bisphenol A and nonylphenol. Overall, these data support the contention that several PFAAs are weak environmental xenoestrogens of potential concern

Quantitative DNA Methylation Analysis of Candidate Genes in Cervical Cancer

<div><p>Aberrant DNA methylation has been observed in cervical cancer; however, most studies have used non-quantitative approaches to measure DNA methylation. The objective of this study was to quantify methylation within a select panel of genes previously identified as targets for epigenetic silencing in cervical cancer and to identify genes with elevated methylation that can distinguish cancer from normal cervical tissues. We identified 49 women with invasive squamous cell cancer of the cervix and 22 women with normal cytology specimens. Bisulfite-modified genomic DNA was amplified and quantitative pyrosequencing completed for 10 genes (<i>APC</i>, <i>CCNA</i>, <i>CDH1</i>, <i>CDH13</i>, <i>WIF1</i>, <i>TIMP3</i>, <i>DAPK1</i>, <i>RARB</i>, <i>FHIT</i>, and <i>SLIT2</i>). A Methylation Index was calculated as the mean percent methylation across all CpG sites analyzed per gene (~4-9 CpG site) per sequence. A binary cut-point was defined at >15% methylation. Sensitivity, specificity and area under ROC curve (AUC) of methylation in individual genes or a panel was examined. The median methylation index was significantly higher in cases compared to controls in 8 genes, whereas there was no difference in median methylation for 2 genes. Compared to HPV and age, the combination of DNA methylation level of <i>DAPK1</i>, <i>SLIT2</i>, <i>WIF1</i> and <i>RARB</i> with HPV and age significantly improved the AUC from 0.79 to 0.99 (95% CI: 0.97–1.00, <i>p-value</i> = 0.003). Pyrosequencing analysis confirmed that several genes are common targets for aberrant methylation in cervical cancer and DNA methylation level of four genes appears to increase specificity to identify cancer compared to HPV detection alone. Alterations in DNA methylation of specific genes in cervical cancers, such as <i>DAPK1</i>, <i>RARB</i>, <i>WIF1</i>, and <i>SLIT2</i>, may also occur early in cervical carcinogenesis and should be evaluated.</p></div