INVESTIGATION OF OMNIVOROUS TROPHIC POSITION IN THE DRILLING GASTROPOD, UROSALPINX CINEREA, USING STABLE ISOTOPE ANALYSIS

Drill-holes found in the fossil record are an important tool to study ecological patterns of the past. It is therefore important to gain a better understanding of the role of extant drilling snails in modern ecosystems. Although traditionally considered a predator, trophic position of 3.0, specimens of the muricid Urosalpinx cinerea from Long Island Sound revealed trophic positions between 2.3 and 2.5, suggestive of an omnivorous diet. This study addresses the generality of this result by examining a U. cinerea population from Wilmington, North Carolina. Preliminary whole body, soft tissue stable isotope analysis of nitrogen and carbon was conducted on five U. cinerea specimens. Isotopic baseline for the study area was calculated using proxy taxa, including Geukensia demissa for the pelagic baseline and Littoraria irrorata for the littoral baseline. Trophic position for these U. cinerea specimens ranged from 2.4 to 2.9. Working hypotheses to explain a trophic position lower than 3.0 in U. cinerea include: trophic omnivory driven by plant consumption, or a lower-than-average nitrogen discrimination factor. Although no studies on the nitrogen fractionation factors of muricids currently exist, the naticid Neverita duplicata from Long Island Sound has recently been demonstrated to have a normal nitrogen fractionation factor and omnivorous isotopic signatures. The difference between the trophic ranges of the two locations may indicate that U. cinerea have a more predatory diet in North Carolina than in Long Island Sound. However, further work is needed to confirm that these values reflect dietary differences, not a below average nitrogen fractionation factor

What is a plant gall and how do insects make them?

Abstract only availableGalls are novel plant organs, produced under the insect's direction. These ecotopic organs provide food and shelter for the developing larvae. The cell of many galls are richer in starch and sugars than normal tissues and the insect uses this rich food to grow in a protected place. In a previous study of galls on grape leaves, the lab found that plant genes specifying the vegetative-to-reproductive transition and fruit and seed identity were expressed in developing galls. To fully test the hypothesis that insects make plant galls by upregulating fruit genes, one needs to block expression of the genes and show that a gall can't be made. This is difficult to do in grape but can be done in poplar, so we are working with galls on poplar leaves. In poplar leaves with or without galls, sectioned and stained using Toluene Blue O dye and examined under polarized light at 20 magnification, we identified changes that galls make in leaf development. We detected a number of histological changes in galled leaves, including patterning of xylem & phloem, palisade and spongy parenchyma. We prepared RNA from fruit, ungalled leaf and galled leaf to study diffences in their expression of meristem identity and carpel genes. Although we didn't have time to do the gene expression work, we predict that the expression of fruit genes will be elevated in the gall tissue compared to surrounding normal leaf tissue.Gyeongsang National Universit

Adjusting for treatment switching in the METRIC study shows further improved overall survival with trametinib compared with chemotherapy

Trametinib, a selective inhibitor of mitogen-activated protein kinase kinase 1 (MEK1) and MEK2, significantly improves progression-free survival compared with chemotherapy in patients with BRAF V600E/K mutation–positive advanced or metastatic melanoma (MM). However, the pivotal clinical trial permitted randomized chemotherapy control group patients to switch to trametinib after disease progression, which confounded estimates of the overall survival (OS) advantage of trametinib. Our purpose was to estimate the switching-adjusted treatment effect of trametinib for OS and assess the suitability of each adjustment method in the primary efficacy population. Of the patients randomized to chemotherapy, 67.4% switched to trametinib. We applied the rank-preserving structural failure time model, inverse probability of censoring weights, and a two-stage accelerated failure time model to obtain estimates of the relative treatment effect adjusted for switching. The intent-to-treat (ITT) analysis estimated a 28% reduction in the hazard of death with trametinib treatment (hazard ratio [HR], 0.72; 95% CI, 0.52–0.98) for patients in the primary efficacy population (data cut May 20, 2013). Adjustment analyses deemed plausible provided OS HR point estimates ranging from 0.48 to 0.53. Similar reductions in the HR were estimated for the first-line metastatic subgroup. Treatment with trametinib, compared with chemotherapy, significantly reduced the risk of death and risk of disease progression in patients with BRAF V600E/K mutation–positive advanced melanoma or MM. Adjusting for switching resulted in lower HRs than those obtained from standard ITT analyses. However, CI are wide and results are sensitive to the assumptions associated with each adjustment method

The masses of Local Group dwarf spheroidal galaxies: The death of the universal mass profile

We investigate the claim that all dwarf spheroidal galaxies (dSphs) reside within halos that share a common, universal mass profile as has been derived for dSphs of the Galaxy. By folding in kinematic information for 25 Andromeda dSphs, more than doubling the previous sample size, we find that a singular mass profile can not be found to fit all the observations well. Further, the best-fit dark matter density profile measured for solely the Milky Way dSphs is marginally discrepant (at just beyond the 1 sigma level) with that of the Andromeda dSphs, where a profile with lower maximum circular velocity, and hence mass, is preferred. The agreement is significantly better when three extreme Andromeda outliers, And XIX, XXI and XXV, all of which have large half-light radii (>600pc) and low velocity dispersions (sigma_v < 5km/s) are omitted from the sample. We argue that the unusual properties of these outliers are likely caused by tidal interactions with the host galaxy.Comment: ApJ in press, 16 pages, 7 figures. Updated to address referee comment

How Will the Future of Work Shape Osh Research and Practice? a Workshop Summary

Growth of the information economy and globalization of labor markets will be marked by exponential growth in emerging technologies that will cause considerable disruption of the social and economic sectors that drive the global job market. These disruptions will alter the way we work, where we work, and will be further affected by the changing demographic characteristics and level of training of the available workforce. These changes will likely result in scenarios where existing workplace hazards are exacerbated and new hazards with unknown health effects are created. The pace of these changes heralds an urgent need for a proactive approach to understand the potential effects new and emerging workplace hazards will have on worker health, safety, and well-being. As employers increasingly rely on non-standard work arrangements, research is needed to better understand the work organization and employment models that best support decent work and improved worker health, safety, and well-being. This need has been made more acute by the SARS-CoV-2 global pandemic that has resulted in dramatic changes in employment patterns, millions of lost jobs, an erosion of many economic sectors, and widespread disparities which further challenge occupational safety and health (OSH) systems to ensure a healthy and productive workplace. to help identify new research approaches to address OSH challenges in the future, a virtual workshop was organized in June 2020 with leading experts in the fields of OSH, well-being, research methods, mental health, economics, and life-course analysis. A paradigm shift will be needed for OSH research in the future of work that embraces key stakeholders and thinks differently about research that will improve lives of workers and enhance enterprise success. A more transdisciplinary approach to research will be needed that integrates the skills of traditional and non-traditional OSH research disciplines, as well as broader research methods that support the transdisciplinary character of an expanded OSH paradigm. This article provides a summary of the presentations, discussion, and recommendations that will inform the agenda of the Expanded Focus for Occupational Safety and Health (Ex4OSH) International Conference, planned for December 2021

A kinematic study of the Andromeda dwarf spheroidal system

We present a homogeneous kinematic analysis of red giant branch stars within 18 of the 28 Andromeda dwarf spheroidal (dSph) galaxies, obtained using the Keck I LRIS and Keck II DEIMOS spectrographs. Based on their g-i colors (taken with the CFHT MegaCam imager), physical positions on the sky, and radial velocities, we assign probabilities of dSph membership to each observed star. Using this information, the velocity dispersions, central masses and central densities of the dark matter halos are calculated for these objects, and compared with the properties of the Milky Way dSph population. We also measure the average metallicity ([Fe/H]) from the co-added spectra of member stars for each M31 dSph and find that they are consistent with the trend of decreasing [Fe/H] with luminosity observed in the Milky Way population. We find that three of our studied M31 dSphs appear as significant outliers in terms of their central velocity dispersion, And XIX, XXI and XXV, all of which have large half-light radii (>700 pc) and low velocity dispersions (sigma_v<5 km/s). In addition, And XXV has a mass-to-light ratio within its half-light radius of just [M/L]_{half}=10.3^{+7.0}_{-6.7}, making it consistent with a simple stellar system with no appreciable dark matter component within its 1 sigma uncertainties. We suggest that the structure of the dark matter halos of these outliers have been significantly altered by tides.Comment: 41 pages, 23 figures. Accepted for publication in Ap

Validation of a touchscreen assessment tool to screen for cognitive delay at 24 months

Aim: To validate a touchscreen assessment as a screening tool for mild cognitive delay in typically developing children aged 24 months. Method: Secondary analysis of data was completed from an observational birth cohort study (The Cork Nutrition & Microbiome Maternal–Infant Cohort Study [COMBINE]), with children born between 2015 and 2017. Outcome data were collected at 24 months of age, at the INFANT Research Centre, Ireland. Outcomes were the Bayley Scales of Infant and Toddler Development, Third Edition cognitive composite score and a language-free, touchscreen-based cognitive measure (Babyscreen). Results: A total of 101 children (47 females, 54 males) aged 24 months (mean = 24.25, SD = 0.22) were included. Cognitive composite scores correlated with the total number of Babyscreen tasks completed, with moderate concurrent validity (r = 0.358, p < 0.001). Children with cognitive composite scores lower than 90 (1 SD below the mean, defined as mild cognitive delay) had lower mean Babyscreen scores than those with cognitive scores equal to or greater than 90 (8.50 [SD = 4.89] vs 12.61 [SD = 3.68], p = 0.001). The area under the receiver operating characteristic curve for the prediction of a cognitive composite score less than 90 was 0.75 (95% confidence interval = 0.59–0.91; p = 0.006). Babyscreen scores less than 7 were equivalent to less than the 10th centile and identified children with mild cognitive delay with 50% sensitivity and 93% specificity. Interpretation: Our 15-minute, language-free touchscreen tool could reasonably identify mild cognitive delay among typically developing children

Acute Liver Failure (ALF) in Pregnancy: How Much Is Pregnancy Related?

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/163471/1/hep31144.pd