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We report a comprehensive multi-year study of thermophilic fungi at the Sevilleta National Wildlife Refuge in central New Mexico. Recovery of thermophilic fungi from soils showed seasonal fluctuations, with greater abundance correlating with spring and summer precipitation peaks. In addition to grassland soils, we obtained and characterized isolates from grassland and riparian litter, herbivore dung and biological soil crusts. All strains belonged to either the Eurotiales or Sordariales (Chaetomiaceae). No particular substrate or microhabitat associations were detected. Molecular typing of strains revealed substantial phylogenetic diversity, eight ad hoc phylogroups across the two orders were identified and genetic diversity was present within each phylogroup. Growth tests over a range of temperatures showed substantial variation in maximum growth rates among strains and across phylogroups but consistency within phylogroups. Results demonstrated that 45–50 C represents the optimal temperature for growth of most isolates, with a dramatic decline at 60 C. Most strains grew at 60 C, albeit slowly, whereas none grew at 65 C, providing empirical confirmation that 60 C presents an evolutionary threshold for fungal growth. Our results support the hypothesis that fungal thermophily is an adaptation to transient seasonal and diurnal high temperatures, rather than simply an adaptation to specialized high-temperature environments. We note that the diversity observed among strains and the frequently confused taxonomy within these groups highlight the need for comprehensive biosystematic revision of thermophilic taxa in both orders.

In this work we propose a new method for investigating connection problems for the class of nonlinear second‐order differential equations known as the Painlevé equations. Such problems can be characterized by the question as to how the asymptotic behaviours of solutions are related as the independent variable is allowed to pass towards infinity along different directions in the complex plane. Connection problems have been previously tackled by a variety of methods. Frequently these are based on the ideas of isomonodromic deformation and the matching of WKB solutions. However, the implementation of these methods often tends to be heuristic in nature and so the task of rigorising the process is complicated. The method we propose here develops uniform approximations to solutions. This removes the need to match solutions, is rigorous, and can lead to the solution of connection problems with minimal computational effort. Our method relies on finding uniform approximations of differ ential equations of the generic form $$ \frac{{\text d}^2\phi}{{\text d}\eta^2} = - \xi^2F(\eta,\xi)\phi $$ as the complex‐valued parameter $\xi \to \infty$. The details of the treatment rely heavily on the locations of the zeros of the function Fin this limit. If they are isolated, then a uniform approximation to solutions can be derived in terms of Airy functions of suitable argument. On the other hand, if two of the zeros of Fcoalesce as $|\xi| \to \infty$, then an approximation can be derived in terms of parabolic cylinder functions. In this paper we discuss both cases, but illustrate our technique in action by applying the parabolic cylinder case to the “classical” connection problem associated with the second Painlevé transcendent. Future papers will show how the technique can be applied with very little change to the other Painlevé equations, and to the wider problem of the asymptotic behavio ur of the general solution to any of these equations.

The article offers information on the implication of the scheduled multiple-reaction-monitoring (Scheduled MRM) mode acquisition during LC-MS/MS analysis.