Colour moult phenology and camouflage mismatch in polymorphic populations of Arctic foxes.

Species that seasonally moult from brown to white to match snowy backgrounds become conspicuous and experience increased predation risk as snow cover duration declines. Long-term adaptation to camouflage mismatch in a changing climate might occur through phenotypic plasticity in colour moult phenology and or evolutionary shifts in moult rate or timing. Also, adaptation may include evolutionary shifts towards winter brown phenotypes that forgo the winter white moult.

Contrasting seasonal effects of climate change influence density in a cold-adapted species.

Many ecological processes are profoundly influenced by abiotic factors, such as temperature and snow. However, despite strong evidence linking shifts in these ecological processes to corresponding shifts in abiotic factors driven by climate change, the mechanisms connecting population size to season-specific climate drivers are little understood. Using a 21-year dataset and a Bayesian state space model, we identified biologically informed seasonal climate covariates that influenced densities of snowshoe hares (Lepus americanus), a cold-adapted boreal herbivore.

Lack of phenological shift leads to increased camouflage mismatch in mountain hares.

Understanding whether organisms will be able to adapt to human-induced stressors currently endangering their existence is an urgent priority. Globally, multiple species moult from a dark summer to white winter coat to maintain camouflage against snowy landscapes. Decreasing snow cover duration owing to climate change is increasing mismatch in seasonal camouflage.

In vitro stability and in vivo pharmacokinetics of the novel ketogenic ester, bis hexanoyl (R)-1,3-butanediol.

A novel ketone ester, bis hexanoyl (R)-1,3-butanediol (BH-BD), has been developed as a means to elevate blood ketones, for use as an energy substrate and a signaling metabolite. The metabolism of BH-BD and its effects on blood beta-hydroxybutyrate (BHB) levels was evaluated in various in vitro matrices and through analysis of plasma collected from Sprague Dawley rats and C57/BL6 mice in two oral gavage studies. A well-characterized ketone ester, (R)-3-hydroxybutyl (R)-3-hydroxybutyrate (HB-BHB), was used as an active control throughout.

Identifying Candidate Genetic Markers of CDV Cross-Species Pathogenicity in African Lions.

Canine distemper virus (CDV) is a multi-host pathogen with variable clinical outcomes of infection across and within species. We used whole-genome sequencing (WGS) to search for viral markers correlated with clinical distemper in African lions. To identify candidate markers, we first documented single-nucleotide polymorphisms (SNPs) differentiating CDV strains associated with different clinical outcomes in lions in East Africa.

Iminophosphorano-Substituted Bispyridinylidenes: Redox Potentials and Substituent Constants from Tolman Electronic Parameters.

Bispyridinylidenes (BPYs) have emerged as an important class of neutral organic electron donors, with redox potentials that vary widely with choice of substituent. Methods to predict the effect of substitution on the redox potential are therefore highly desirable. Here we show that the redox potential of BPYs featuring iminophosphorano substituents (R P=N-), which represent the most reducing class of BPYs, can be predicted based on the well-known Tolman electronic parameter (TEP) for the respective phosphine fragment (R P).

The Origin and Spread of Locally Adaptive Seasonal Camouflage in Snowshoe Hares.

AbstractAdaptation is central to population persistence in the face of environmental change, yet we seldom precisely understand the origin and spread of adaptive variation in natural populations. Snowshoe hares () along the Pacific Northwest coast have evolved brown winter camouflage through positive selection on recessive variation at the pigmentation gene introgressed from black-tailed jackrabbits (). Here, we combine new and published whole-genome and exome sequences with targeted genotyping of to investigate the evolutionary history of local seasonal camouflage adaptation in the Pacific Northwest.

Moiré Band Topology in Twisted Bilayer Graphene.

Recently twisted bilayer graphene (t-BLG) has emerged as a strongly correlated physical platform. Besides the apparent significance of band flatness, band topology may be another critical element in t-BLG and yet receives much less attention. Here we report the compelling evidence for nontrivial noninteracting Moiré band topology in t-BLG through a systematic nonlocal transport study and a -theory examination.

Snow-mediated plasticity does not prevent camouflage mismatch.

Global reduction in snow cover duration is one of the most consistent and widespread climate change outcomes. Declining snow duration has severe negative consequences for diverse taxa including seasonally color molting species, which rely on snow for camouflage. However, phenotypic plasticity may facilitate adaptation to reduced snow duration.

Data Mining to Determine the Influence of Fluid Properties on the Integrity Test Values.

Eudralex volume 4, Annex 1, the European Union Good Manufacturing Practice for sterile products, requires that "The integrity of the sterilised filter should be verified before use" (1). Implicit in this requirement for a PUPSIT is the rationale that the sterilizing filter could sustain damage during sterilization or use (i.e.

Cross-species transmission and evolutionary dynamics of canine distemper virus during a spillover in African lions of Serengeti National Park.

The outcome of pathogen spillover from a reservoir to a novel host population can range from a "dead-end" when there is no onward transmission in the recipient population, to epidemic spread and even establishment in new hosts. Understanding the evolutionary epidemiology of spillover events leading to discrete outcomes in novel hosts is key to predicting risk and can lead to a better understanding of the mechanisms of emergence. Here we use a Bayesian phylodynamic approach to examine cross-species transmission and evolutionary dynamics during a canine distemper virus (CDV) spillover event causing clinical disease and population decline in an African lion population (Panthera leo) in the Serengeti Ecological Region between 1993 and 1994.

Convergent evolution of seasonal camouflage in response to reduced snow cover across the snowshoe hare range.

Determining how different populations adapt to similar environments is fundamental to understanding the limits of adaptation under changing environments. Snowshoe hares (Lepus americanus) typically molt into white winter coats to remain camouflaged against snow. In some warmer climates, hares have evolved brown winter camouflage-an adaptation that may spread in response to climate change.

Noninvasive measures of physiological stress are confounded by exposure.

Glucocorticoids and glucocorticoid metabolites are increasingly used to index physiological stress in wildlife. Although feces is often abundant and can be collected noninvasively, exposure to biotic and abiotic elements may influence fecal glucocorticoid metabolite (FGM) concentrations, leading to inaccurate conclusions regarding wildlife physiological stress. Using captive snowshoe hares (Lepus americanus) and simulated environmental conditions, we evaluated how different realistic field conditions and temporal sampling constraints might influence FGM concentrations using an 11-oxoetiocholanolone-enzyme immunoassay.

Photo-induced terahertz near-field dynamics of graphene/InAs heterostructures.

In this letter, we report optical pump terahertz (THz) near-field probe (n-OPTP) and optical pump THz near-field emission (n-OPTE) experiments of graphene/InAs heterostructures. Near-field imaging contrasts between graphene and InAs using these newly developed techniques as well as spectrally integrated THz nano-imaging (THz s-SNOM) are systematically studied. We demonstrate that in the near-field regime (λ/6000), a single layer of graphene is transparent to near-IR (800 nm) optical excitation and completely "screens" the photo-induced far-infrared (THz) dynamics in its substrate (InAs).

Record-Low and Anisotropic Thermal Conductivity of a Quasi-One-Dimensional Bulk ZrTe Single Crystal.

Zirconium pentatelluride (ZrTe) has recently attracted renewed interest owing to many of its newly discovered extraordinary physical properties, such as 2D and 3D topological-insulator behavior, pressure-induced superconductivity, Weyl semimetal behavior, Zeeman splitting, and resistivity anomaly. The quasi-one-dimensional structure of single-crystal ZrTe also promises large anisotropy in its thermal properties, which have not yet been studied. In this work, via time-domain thermoreflectance measurements, ZrTe single crystals are discovered to possess a record-low thermal conductivity along the b-axis (through-plane), as small as 0.

Adaptive introgression underlies polymorphic seasonal camouflage in snowshoe hares.

Snowshoe hares () maintain seasonal camouflage by molting to a white winter coat, but some hares remain brown during the winter in regions with low snow cover. We show that cis-regulatory variation controlling seasonal expression of the gene underlies this adaptive winter camouflage polymorphism. Genetic variation at clustered by winter coat color across multiple hare and jackrabbit species, revealing a history of recurrent interspecific gene flow.

Is the Red Wolf a Listable Unit Under the US Endangered Species Act?

Defining units that can be afforded legal protection is a crucial, albeit challenging, step in conservation planning. As we illustrate with a case study of the red wolf (Canis rufus) from the southeastern United States, this step is especially complex when the evolutionary history of the focal taxon is uncertain. The US Endangered Species Act (ESA) allows listing of species, subspecies, or Distinct Population Segments (DPSs) of vertebrates.

Winter color polymorphisms identify global hot spots for evolutionary rescue from climate change.

Maintenance of biodiversity in a rapidly changing climate will depend on the efficacy of evolutionary rescue, whereby population declines due to abrupt environmental change are reversed by shifts in genetically driven adaptive traits. However, a lack of traits known to be under direct selection by anthropogenic climate change has limited the incorporation of evolutionary processes into global conservation efforts. In 21 vertebrate species, some individuals undergo a seasonal color molt from summer brown to winter white as camouflage against snow, whereas other individuals remain brown.

Within-sample variation in snowshoe hare faecal glucocorticoid metabolite measurements.

Faecal glucocorticoid metabolite (FGM) concentrations are used increasingly as a non-invasive measure to index physiological stress experienced by diverse taxa. However, FGM may not be evenly distributed throughout a faecal mass or faecal pellet group. Moreover, within-sample variation in FGM measurements associated with different sampling and/or processing techniques is rarely reported despite potentially having important implications for inferring stress levels in free-ranging wildlife.

Genetic sampling for estimating density of common species.

Understanding population dynamics requires reliable estimates of population density, yet this basic information is often surprisingly difficult to obtain. With rare or difficult-to-capture species, genetic surveys from noninvasive collection of hair or scat has proved cost-efficient for estimating densities. Here, we explored whether noninvasive genetic sampling (NGS) also offers promise for sampling a relatively common species, the snowshoe hare ( Erxleben, 1777), in comparison with traditional live trapping.