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The influence of maternal nesting behaviour on offspring survival: evidence from correlational and cross-fostering studies
No full textThe maternal effect of nesting behaviour is important in oviparous species because choice of microhabitat (e.g. shade cover, temperature) can determine the environment in which embryos develop. In turn, this maternal choice can influence developmental trajectories and offspring phenotypes and survival. We studied maternal nesting behaviour in a western painted turtle, Chrysemys picta, population in northern Idaho, U.S.A. During 2013–2016, we examined maternal choice of nest microhabitat and used correlational data to quantify consequences on egg survival. In 2017, we conducted a cross-fostering experiment to decouple the effects of intrinsic maternal effects from extrinsic environmental factors on egg survival, while simultaneously manipulating the level of nest shade cover and distance from water using artificial nests. Females chose nest sites that were more open and warmer than randomly available habitat. Additionally, of three nesting areas, the coolest area with the most shade cover was used least by nesting females. Egg survival was associated with nest temperature in some, but not all, years. In the cross-fostering experiment, egg survival did not differ between natal and foster eggs, but was greater in maternal nests than in artificial nests. Additionally, egg survival increased with canopy openness and minimum nest temperature, especially for eggs in artificial nests. Overall, these results suggest that females select nesting conditions (warm and open nest sites) that positively affect hatching success.Ye
The interaction-induced dipole of H-2-H: New ab initio results and spherical tensor analysis
Get PDFWe present numerical results for the dipole induced by interactions between a hydrogen molecule and a hydrogen atom, obtained from finite-field calculations in an aug-cc-pV5Z basis at the unrestricted coupled-cluster level including all single and double excitations in the exponential operator applied to a restricted Hartree-Fock reference state, with the triple excitations treated perturbatively, i.e., UCCSD(T) level. The Cartesian components of the dipole have been computed for nine different bond lengths r of H-2 ranging from 0.942 a.u. to 2.801 a.u., for 16 different separations R between the centers of mass of H-2 and H between 3.0 a.u. and 10.0 a.u., and for 19 angles theta between the H2 bond vector r and the vector R from the H-2 center of mass to the nucleus of the H atom, ranging from 0 degrees to 90 degrees in intervals of 5 degrees. We have expanded the interaction-induced dipole as a series in the spherical harmonics of the orientation angles of the H-2 bond axis and of the intermolecular vector, with coefficients D-lambda L(r, R). For the geometrical configurations that we have studied in this work, the most important coefficients D?L(r, R) in the series expansion are D-01(r, R), D-21(r, R), D-23(r, R), D-43(r, R), and D-45(r, R). We show that the ab initio results for D-23(r, R) and D-45(r, R) converge to the classical induction forms at large R. The convergence of D-45(r, R) to the hexadecapolar induction form is demonstrated for the first time. Close agreement between the long-range ab initio values of D-01(r(0) = 1.449 a.u., R) and the known analytical values due to van der Waals dispersion and back induction is also demonstrated for the first time. At shorter range, D-01(r, R) characterizes isotropic overlap and exchange effects, as well as dispersion. The coefficients D-21(r, R) and D-43(r, R) represent anisotropic overlap effects. Our results for the D-lambda L(r, R) coefficients are useful for calculations of the line shapes for collision-induced absorption and collision-induced emission in the infrared and far-infrared by gas mixtures containing both H-2 molecules and H atoms. Published under license by AIP Publishing
George Eliot's Heirs: The Lewes Line
No full textArticle from the George Eliot Review, digitized and hosted by the George Eliot Review Online.Publishe
George Eliot's Heirs: The Lewes Line
No full textArticle from the George Eliot Review, digitized and hosted by the George Eliot Review Online.Publishe
Do Students Use Their ePortfolios After Graduation? A Pilot Study of Undergraduate and Graduate Students
No full textPublishedN
Spin splittings from first-order symmetry-adapted perturbation theory without single-exchange approximation
Get PDFThe recently proposed spin-flip symmetry-adapted perturbation theory (SF-SAPT) first-order exchange energy [Patkowski et al., J. Chem. Phys. 148, 164110 (2018)] enables the standard open-shell SAPT approach to treat arbitrary spin states of the weakly interacting complex. Here, we further extend first-order SF-SAPT beyond the single-exchange approximation to a complete treatment of the exchanges of electrons between monomers. This new form of the exchange correction replaces the single-exchange approximation with a more moderate single-spin-flip approximation. The newly developed expressions are applied to a number of small test systems to elucidate the quality of both approximations. They are also applied to the singlet-triplet splittings in pancake bonded dimers. The accuracy of the single-exchange approximation deteriorates at short intermolecular separations, especially for systems with few electrons and for the high-spin state of the complex. In contrast, the single-spin-flip approximation is exact for interactions involving a doublet molecule and remains highly accurate for any number of unpaired electrons. Because the single-exchange approximation affects the high-spin and low-spin states of pancake bonded complexes evenly, the resulting splitting values are of similar accuracy to those produced by the formally more accurate single-spin-flip approximation. Published under license by AIP Publishing.Publishe
The Wonder Grass: The Story of Tall Fescue in the United States
No full textFrom its origins in Europe, its unlikely beginnings in the United States, the controversy surrounding its initial release and issues with fescue toxicosis, “The Wonder Grass” is a fascinating examination of the history and modern uses of forage tall fescue.
The book was written by former Auburn University Professor Don Ball, former University of Kentucky professor Garry Lacefield and former University of Georgia professor Carl Hoveland. It takes a comprehensive look at the species, starting with how in 1893, a farmer in the mountains of eastern Kentucky noticed that a grass on his farm remained green during cooler months when most other plants were dormant and brown.PublishedN
Satellite Observations of the Recovery of Forests and Grasslands in Western China
Get PDFThe Grain for Green Program (GGP), which combats and reverses the landscape-scale habitat degradation by converting agricultural lands to forests and grasslands, was launched in 1999 in western China. An assessment of the extent to which the GGP has altered the vegetation cover and ecological functions in these regions is much needed. The present study initially analyzed land use and cover change of forests and grasslands over western China between 2000 and 2015. A variety of satellite-based ecological indicators, including net primary productivity, normalized difference vegetation index, leaf area index, carbon use efficiency, and water use efficiency, were used to reflect the biophysical consequences of the GGP in western China. Results indicated that the spatial extent of forests and grasslands increased by 13.97 x 10(3) and 11.13 x 10(3) km(2), respectively, which were mainly converted from deserts and croplands. The ecosystem functions of forests and grasslands showed an asymmetric response in northwestern and southwestern China. The normalized difference vegetation index and water use efficiency of forests, as well as the net primary productivity and water use efficiency of grasslands, increased significantly over this period. The GGP also has led to an increase in leaf area index and carbon use efficiency of forests and grasslands. The Loess Plateau and the Three Rivers Source area represent the most effectively recovered regions in western China. Rising precipitation rates have contributed to vegetation recovery to some extent, especially in northwestern China, whereas the GGP was the prominent reason for the improvement of ecosystem functions across the entire region of western China. Plain Language Summary Land degradation has caused severe environmental problems in many areas worldwide and severely restrains the sustainable development of numerous local economies. Land degradation also undermines the livelihoods and food security of people, especially in the economically underprivileged regions. Western China has experienced land degradation because of both its geological location and climatic conditions. To combat and mitigate this situation, the Chinese government implemented a series of national-scale ecological policies and programs during the late 1990s and early 2000s. Nearly 20 years have passed since the implementation of these projects. Therefore, it is appropriate to comprehensively assess the biophysical consequences of these programs. The present study aims to evaluate the extent to which the vegetation of western China recovered during the 2000-2015 period based on a variety of remotely sensed data streams. Results indicated that the spatial extent of forests and grasslands have expanded. The ecosystem functions of forests and grasslands showed an asymmetric response in the southwest and northwest regions of western China. These findings may provide guidelines for government agencies and policy makers involved in initiating adaptation strategies designed to adapt to climate change and to manage vegetation production.PublishedYe
Who let the cats out? A global meta-analysis on risk of parasitic infection in indoor versus outdoor domestic cats (Felis catus)
Get PDFParasitic infection risks in domestic animals may increase as a result of outdoor activities, often leading to transmission events to and from owners, other domestic animals and wildlife. Furthermore, outdoor access has not been quantified in domestic animals as a risk factor with respect to latitude or parasite transmission pathway. Cats are an ideal model to test parasitic infection risk in outdoor animals because there have been many studies analysing this risk factor in this species; and there is a useful dichotomy in cat ownership between indoor-only cats and those with outdoor access. Thus, we used meta-analysis to determine whether outdoor access is a significant risk factor for parasitic infection in domestic pet cats across 19 different pathogens including many relevant to human, domestic animal and wildlife health, such as Toxoplasma gondii and Toxocara cati. Cats with outdoor access were 2.77 times more likely to be infected with parasites than indoor-only cats. Furthermore, absolute latitude trended towards significance such that each degree increase in absolute latitude increased infection likelihood by 4%. Thus, restricting outdoor access can reduce the risk of parasitic infection in cats and reduce the risk of zoonotic parasite transmission, spillover to sympatric wildlife and negative impacts on feline health.PublishedYe