Glaze Station Expansion and Building

https://scholarworks.moreheadstate.edu/student_scholarship_posters/1042/thumbnail.jp

Search strategies improve with practice, but not with time pressure or financial incentives

Peer reviewedPostprin

Graduate Teaching Communities of Practice: Fostering a Sense of Belonging and Professional Development for Graduate Students, by Graduate Students

Communities of Practice provide explicit formal recognition for teaching work and serve as a network of pedagogical resources. Communities of Practice create a safe space and a strengthened sense of community. Communities of Practice can be formed anywhere to meet any set of needs but always thrive with members’ agency and institutional support

Possible future scenarios for two major Arctic Gateways connecting Subarctic and Arctic marine systems: I. Climate and physical-chemical oceanography

We review recent trends and projected future physical and chemical changes under climate change in transition zones between Arctic and Subarctic regions with a focus on the two major inflow gateways to the Arctic, one in the Pacific (i.e. Bering Sea, Bering Strait, and the Chukchi Sea) and the other in the Atlantic (i.e. Fram Strait and the Barents Sea). Sea-ice coverage in the gateways has been disappearing during the last few decades. Projected higher air and sea temperatures in these gateways in the future will further reduce sea ice, and cause its later formation and earlier retreat. An intensification of the hydrological cycle will result in less snow, more rain, and increased river runoff. Ocean temperatures are projected to increase, leading to higher heat fluxes through the gateways. Increased upwelling at the Arctic continental shelf is expected as sea ice retreats. The pH of the water will decline as more atmospheric CO2 is absorbed. Long-term surface nutrient levels in the gateways will likely decrease due to increased stratification and reduced vertical mixing. Some effects of these environmental changes on humans in Arctic coastal communities are also presented.publishedVersio

A census of X-ray nuclear activity in nearby galaxies

We have studied the X-ray nuclear activity of 187 nearby (distance < 15 Mpc) galaxies observed with Chandra/ACIS. We found that 86 of them have a point-like X-ray core, consistent with an accreting black hole (BH). We argue that the majority of them are nuclear BHs, rather than X-ray binaries. The fraction of galaxies with an X-ray detected nuclear BH is higher (~60 per cent) for ellipticals and early-type spirals (E to Sb), and lower (~30 per cent) for late-type spirals (Sc to Sm). There is no preferential association of X-ray cores with a large-scale bar; in fact, strongly barred galaxies appear to have slightly lower detection fraction and luminosity for their nuclear X-ray sources, compared with non-barred or weakly barred galaxies of similar Hubble types. The cumulative luminosity distribution of the nuclear sources in the 0.3-8 keV band is a power-law with slope ~-0.5, from ~2 x 10^{38} erg/s to ~10^{42} erg/s. The Eddington ratio is lower for ellipticals (L_{X}/L_{Edd} ~ 10^{-8}) and higher for late-type spirals (up to L_{X}/L_{Edd} ~ 10^{-4}), but in all cases, the accretion rate is low enough to be in the radiatively-inefficient regime. The intrinsic NH is generally low, especially for the less luminous sources: there appear to be no Type-2 nuclear BHs at luminosities <~ 10^{39} erg/s. The lack of a dusty torus or of other sources of intrinsic absorption (e.g., an optically-thick disk wind) may be directly related to the lack of a standard accretion disk around those faint nuclear BHs. The fraction of obscured sources increases with the nuclear BH luminosity: 2/3 of the sources with L_{X} > 10^{40} erg/s have a fitted NH > 10^{22} cm^{-2}. This is contrary to the declining trend of the obscured fraction with increasing luminosities, observed in more luminous AGN and quasars.Comment: 27 pages, 353 kB, accepted by Ap

Future Contingents and the Logic of Temporal Omniscience

At least since Aristotle’s famous 'sea-battle' passages in On Interpretation 9, some substantial minority of philosophers has been attracted to the doctrine of the open future--the doctrine that future contingent statements are not true. But, prima facie, such views seem inconsistent with the following intuition: if something has happened, then (looking back) it was the case that it would happen. How can it be that, looking forwards, it isn’t true that there will be a sea battle, while also being true that, looking backwards, it was the case that there would be a sea battle? This tension forms, in large part, what might be called the problem of future contingents. A dominant trend in temporal logic and semantic theorizing about future contingents seeks to validate both intuitions. Theorists in this tradition--including some interpretations of Aristotle, but paradigmatically, Thomason (1970), as well as more recent developments in Belnap, et. al (2001) and MacFarlane (2003, 2014)--have argued that the apparent tension between the intuitions is in fact merely apparent. In short, such theorists seek to maintain both of the following two theses: (i) the open future: Future contingents are not true, and (ii) retro-closure: From the fact that something is true, it follows that it was the case that it would be true. It is well-known that reflection on the problem of future contingents has in many ways been inspired by importantly parallel issues regarding divine foreknowledge and indeterminism. In this paper, we take up this perspective, and ask what accepting both the open future and retro-closure predicts about omniscience. When we theorize about a perfect knower, we are theorizing about what an ideal agent ought to believe. Our contention is that there isn’t an acceptable view of ideally rational belief given the assumptions of the open future and retro-closure, and thus this casts doubt on the conjunction of those assumptions

2MASS photometry of edge-on spiral galaxies. I. Sample and general results

A sample of edge-on spiral galaxies aimed at a study of the main structural and photometric parameters of edge-on galaxies both of early and late types is presented. The data were taken from the 2MASS in the J, H and K_s filters. The sample consists of 175 galaxies in the K_s-filter, 169 galaxies in the H-filter and 165 galaxies in the J-filter. We present bulge and disc decompositions of each galaxy image. All galaxies have been modelled with a Sersic bulge and exponential disc with the BUDDA v2.1 package. The main conclusions of our general statistical analysis of the sample are: (1) The distribution of the apparent bulge axis ratio q_b for the subsample with n < 2 can be attributed to triaxial, nearly prolate bulges that are seen from different projections, while n > 2 bulges seem to be oblate spheroids with moderate flattening. (2) For the sample galaxies, the effective radius of the bulge r_{e,b}, the disc scalelength h and the disc scaleheight z_0 are well correlated. However, there is a clear trend for the ratio r_{e,b}/h to increase with n. (3) There is a hint that the fundamental planes of discs, which links only disc parameters and the maximum rotational velocity of gas, are different for galaxies with different bulges. (4) The investigation of the Photometric Plane of sample bulges shows that the plane is not flat and has a prominent curvature towards small values of n. For bulges this fact was not noticed earlier. (5) The clear relation between the flattening of stellar discs h/z_0 and the relative mass of a spherical component, including a dark halo, is confirmed not for bulgeless galaxies but for galaxies with massive bulges. (Abridged)Comment: 20 pages, 13 figures, accepted for publication in MNRA

Duration of androgen suppression before radiotherapy for localized prostate cancer: Radiation therapy oncology group randomized clinical trial 9910

Purpose To determine whether prolonged androgen suppression (AS) duration before radiotherapy improves survival and disease control in prostate cancer. Patients and Methods One thousand five hundred seventy-nine men with intermediate-risk prostate cancer were randomly assigned to 8 weeks of AS followed by radiotherapy with an additional 8 weeks of concurrent AS (16 weeks total) or to 28 weeks of AS followed by radiotherapy with an additional 8 weeks of AS (36 weeks total). The trial sought primarily to detect a 33% reduction in the hazard of prostate cancer death in the 28-week assignment. Time-to-event end points are reported for up to 10 years of follow-up. Results There were no between-group differences in baseline characteristics of 1,489 eligible patients with follow-up. For the 8- and 28-week assignments, 10-year disease-specific survival rates were 95% (95% CI, 93.3% to 97.0%) and 96% (95% CI, 94.6% to 98.0%; hazard ratio [HR], 0.81; P = .45), respectively, and 10-year overall survival rates were66%(95% CI, 62.0% to 69.9%) and67%(95% CI, 63.0% to 70.8%; HR, 0.95; P = .62), respectively. For the 8- and 28-week assignments, 10-year cumulative incidences of locoregional progression were 6% (95% CI, 4.3% to 8.0%) and 4% (95% CI, 2.5% to 5.7%; HR, 0.65; P = .07), respectively; 10-year distant metastasis cumulative incidences were 6% (95% CI, 4.0% to 7.7%) and 6% (95% CI, 4.0% to 7.6%; HR, 1.07; P = .80), respectively; and 10-year prostate-specific antigen-based recurrence cumulative incidences were 27% (95% CI, 23.1% to 29.8%) and 27% (95% CI, 23.4% to 30.3%; HR, 0.97; P = .77), respectively. Conclusion Extending AS duration from 8 weeks to 28 weeks before radiotherapy did not improve outcomes. A lower than expected prostate cancer death rate reduced ability to detect a between-group difference in disease-specific survival. The schedule of 8 weeks of AS before radiotherapy plus 8 weeks of AS during radiotherapy remains a standard of care in intermediate-risk prostate cancer

State-machine replication for planet-scale systems

Online applications now routinely replicate their data at multiple sites around the world. In this paper we present Atlas, the first state-machine replication protocol tailored for such planet-scale systems. Atlas does not rely on a distinguished leader, so clients enjoy the same quality of service independently of their geographical locations. Furthermore, client-perceived latency improves as we add sites closer to clients. To achieve this, Atlas minimizes the size of its quorums using an observation that concurrent data center failures are rare. It also processes a high percentage of accesses in a single round trip, even when these conflict. We experimentally demonstrate that Atlas consistently outperforms state-of-The-Art protocols in planet-scale scenarios. In particular, Atlas is up to two times faster than Flexible Paxos with identical failure assumptions, and more than doubles the performance of Egalitarian Paxos in the YCSB benchmark.H2020 - Horizon 2020 Framework Programme(825184