536 research outputs found

    The Road to Getting Published

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    Keynote Addres

    Poly[[tetra­kis­(μ2-pyrazine N,N′-dioxide-κ2 O:O′)erbium(III)] tris­(perchlorate)]

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    The title three-dimensional coordination network, {[Er(C4H4N2O2)4](ClO4)3}n, is isostructural to that of other lanthanides. The Er+3 cation lies on a fourfold roto-inversion axis. It is coordinated in a distorted square-anti­prismatic fashion by eight O atoms from bridging pyrazine N,N′-dioxide ligands. There are two unique pyrazine N,N′-dioxide ligands. One ring is located around an inversion center, and there is a a twofold rotation axis at the center of the other ring. There are also two unique perchlorate anions. One is centered on a twofold rotation axis and the other on a fourfold roto-inversion axis. The perchlorate anions are located in channels that run perpendicular to (001) and (110) and inter­act with the coordination network through C—H⋯O hydrogen bonds

    Grains and Oilseed Cropland: A Global Perspective

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    Current tight grain markets have led some commentators to argue that the world is entering a phase of rising food scarcity. The present situation js related to the rise in world consumption, which has tended to outpace production during the 1990s. While most supply shortages were due to weather shocks, the global area planted to grains has decreased from 1,784 million acres in l 980to 1,718 million acres in 1996 (USDA). The question remains, Are there enough land resources available globally to meetfutwe production needs? The combined grains and oilseeds area has, however, increased tWer that same period

    Precession-driven changes in Iceland–Scotland Overflow Water penetration and bottom water circulation on Gardar Drift since ~ 200 ka

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    © The Author(s), 2015. This is the author's version of the work and is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Palaeogeography, Palaeoclimatology, Palaeoecology 440 (2015): 561-563, doi:10.1016/j.palaeo.2015.09.042.Benthic foraminiferal stable isotopic records from a transect of sediment cores south of the Iceland-Scotland Ridge reveal that the penetration depth of Iceland-Scotland Overflow Water (ISOW) varied on orbital timescales with precessional pacing over the past ~ 200 kyr. Similar, higher benthic foraminiferal δ13 C values (~ 1.0 ‰) were recorded at all transect sites downstream of the Iceland-Scotland Ridge during interglacial periods (Marine Isotope Chrons 5 and 1), indicating a deeply penetrating ISOW. During glacial periods (Marine Isotope Chrons 6, 4, and 2), benthic foraminiferal δ13C values from the deeper (2700-3300 m), southern sites within this transect were significantly lower (~ 0.5 ‰) than values from the northern (shallower) portion of the transect (~ 1.0 ‰), reflecting a shoaling of ISOW and greater influence of glacial Southern Component Water (SCW) in the deep Northeast Atlantic. Particularly during intermediate climate states, ISOW strength is driven by precesional cycles, superimposed on the large-scale glacial-interglacial ISOW variability. Millennial-scale variability in the penetration of ISOW, likely caused by high-frequency Heinrich and Dansgaard-Oeschger Events, is most pronounced during intermediate climate states.This research was supported by National Science Foundation grant OCE-0095219 to J.D. Wright2016-10-0

    Poly[[tetra­kis­(μ2-pyrazine N,N′-dioxide-κ2 O:O′)holmium(III)] tris­(perchlorate)]

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    The title three-dimensional coordination network, {[Ho(C4H4N2O2)4](ClO4)3}n, is isostructural to that of other lanthanides. The Ho+3 cation lies on a fourfold roto-inversion axis. It is coordinated in a distorted square anti-prismatic fashion by eight O atoms from bridging pyrazine N,N′-dioxide ligands. There are two unique pyrazine N,N′-dioxide ligands. One ring is located around an inversion center, and there is a a twofold rotation axis at the center of the other ring. There are also two unique perchlorate anions. One is centered on a twofold rotation axis and the other on a fourfold roto-inversion axis. The perchlorate anions are located in channels that run perpendicular to (001) (110) and inter­act with the coordination network through C—H⋯O hydrogen bonds

    Predicting Greater Prairie-Chicken Lek Site Suitability to Inform Conservation Actions

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    The demands of a growing human population dictates that expansion of energy infrastructure, roads, and other development frequently takes place in native rangelands. Particularly, transmission lines and roads commonly divide rural landscapes and increase fragmentation. This has direct and indirect consequences on native wildlife that can be mitigated through thoughtful planning and proactive approaches to identifying areas of high conservation priority. We used nine years (2003–2011) of Greater Prairie-Chicken (Tympanuchus cupido) lek locations totaling 870 unique leks sites in Kansas and seven geographic information system (GIS) layers describing land cover, topography, and anthropogenic structures to model habitat suitability across the state. The models obtained had low omission rates (\u3c0.18) and high area under the curve scores (AUC \u3e0.81), indicating high model performance and reliability of predicted habitat suitability for Greater Prairie-Chickens. We found that elevation was the most influential in predicting lek locations, contributing three times more predictive power than any other variable. However, models were improved by the addition of land cover and anthropogenic features (transmission lines, roads, and oil and gas structures). Overall, our analysis provides a hierarchal understanding of Greater Prairie-Chicken habitat suitability that is broadly based on geomorphological features followed by land cover suitability. We found that when land features and vegetation cover are suitable for Greater Prairie-Chickens, fragmentation by anthropogenic sources such as roadways and transmission lines are a concern. Therefore, it is our recommendation that future human development in Kansas avoid areas that our models identified as highly suitable for Greater Prairie-Chickens and focus development on land cover types that are of lower conservation concern

    A Qualitative Study of the Impact of the COVID-19 Pandemic on Metastatic Breast Cancer Care

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    The COVID-19 pandemic substantially impacted the delivery of oncology care, particularly for individuals with metastatic cancers. The objective of this study was to qualitatively evaluate the impacts of COVID-19 on metastatic breast cancer (MBC) care among patients. This study consisted of 36 semi-structured qualitative interviews conducted virtually with people living with MBC, who were members of a patient support organization called Project Life. Project Life is an MBC patient-led, web-based wellness community. Responses were analyzed using Phronetic Iterative Analysis. Interviews were conducted from March 14, 2022, to May 31, 2022. Analysis from 36 individual in-depth qualitative interviews revealed the following themes during COVID-19: (1) variable preferences for telehealth (2) disruptions to care, (3) virtualization of social care. Wide variations existed in preferences surrounding telehealth, centered around ideas of convenience. Disruptions to care included delays to diagnostic care, isolation from caregivers, and interruptions associated with COVID-19 infection. These results call for adaptability in oncology care given wide-ranging preferences on telehealth and the shifting of available support services

    Estimating total horizontal aeolian flux within shrub-invaded groundwater-dependent meadows using empirical and mechanistic models

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    Wind erosion is a significant environmental problem that removes soil resources from sensitive ecosystems and contributes to air pollution. In regions of shallow groundwater, friable (puffy) soils are maintained through capillary action, surface evaporation of solute-rich soil moisture, and protection from mobilization by groundwater-dependent grasses and shrubs. When a reduction in vegetation cover occurs through any disturbance process, there is potential for aeolian transport and dust emission. We find that as mean gap size between vegetation elements scaled by vegetation height increases, total horizontal aeolian sediment flux increases and explains 58% of the variation in total horizontal aeolian sediment flux. We also test a probabilistic model of wind erosion based on gap size between vegetation elements scaled by vegetation height (the Okin model), which predicts measured total horizontal aeolian sediment flux more closely than another commonly used model based on the average plant area observed in profile (Raupach model). The threshold shear velocity of bare soil appears to increase as gap size between vegetation elements scaled by vegetation height increases, reflecting either surface armoring or reduced interaction between the groundwater capillary zone and surface sediments. This work advances understanding of the importance of measuring gap size between vegetation elements scaled by vegetation height for empirically estimating Q and for structuring process-based models of desert wind erosion in groundwater-dependent vegetation

    Chronoecology of the Cave Dwelling Orb-Weaver Spider, Meta ovalis (Araneae: Tetragnathidae)

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    Circadian clocks are endogenous time keeping mechanisms that are ubiquitous among animals. They enable coordination of many essential biological and metabolic processes in relation to the 24 hour light cycle on earth. However, there are many habitats on earth that are not subject to this light cycle. This study aims to look at the potential genetic drift of the circadian rhythm of a subterranean spider, Meta ovalis, as well as gathering general natural history information on this under-studied spider. This study will fill general gaps in knowledge of this spider and its habitat, highlight the importance of studying organisms within a subterranean environment, and place importance on cave conservation and acquiring knowledge of these specialized, and sensitive species. This study integrates circadian and foraging theory to evaluate species as circadian specialists and generalists based on how narrowly or widely their activity is spread over the 24 h cycle. We suggest that M. ovalis benefits from a generalist strategy, showing small bursts of focused activity widely dispersed across the 24 h cycle, allowing it to capture prey opportunistically whenever it is available. Live spiders were collected from area caves, monitored in an environment controlled for light and temperature, and returned to their cave of origin. The activity of each spider was analyzed for differences in circadian activity among and between populations to determine if there is a significant drift of the circadian strategy between isolated populations of Meta ovalis. We expect to see a different circadian strategy implemented between populations due to drift from the spiders being isolated from other populations
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