Achieving conservation when opportunity costs are high: optimizing reserve design in Alberta's oil sands region.

Recent studies have shown that conservation gains can be achieved when the spatial distributions of biological benefits and economic costs are incorporated in the conservation planning process. Using Alberta, Canada, as a case study we apply these techniques in the context of coarse-filter reserve design. Because targets for ecosystem representation and other coarse-filter design elements are difficult to define objectively we use a trade-off analysis to systematically explore the relationship between conservation targets and economic opportunity costs.

Facultative symbiont infections affect aphid reproduction.

Some bacterial symbionts alter their hosts reproduction through various mechanisms that enhance their transmission in the host population. In addition to its obligatory symbiont Buchnera aphidicola, the pea aphid Acyrthosiphon pisum harbors several facultative symbionts influencing several aspects of host ecology. Aphids reproduce by cyclical parthenogenesis whereby clonal and sexual reproduction alternate within the annual life cycle.

A 10 patient case report on the impact of plasmapheresis upon neutralizing factors against adeno-associated virus (AAV) types 1, 2, 6, and 8.

Adeno-associated viruses (AAV) are small, nonenveloped single-stranded DNA viruses which require helper viruses to facilitate efficient replication. These recombinant viruses are some of the most promising candidates for therapeutic gene transfer to treat many genetic and acquired diseases. Nevertheless, the presence of humoral responses to the wild-type AAV common among humans is one of the limitations of in vivo transduction efficacy in humans using cognate recombinant vector.

Polymers for improving the in vivo transduction efficiency of AAV2 vectors.

Background: Adeno-associated virus has attracted great attention as vehicle for body-wide gene delivery. However, for the successful treatment of a disease such as Duchenne muscular dystrophy infusion of very large amounts of vectors is required. This not only raises questions about the technical feasibility of the large scale production but also about the overall safety of the approach.

The heritability of multiple male mating in a promiscuous mammal.

The tendency of females to mate with multiple males is often explained by direct and indirect benefits that could outweigh the many potential costs of multiple mating. However, behaviour can only evolve in response to costs and benefits if there is sufficient genetic variation on which selection can act. We followed 108 mating chases of 85 North American red squirrels (Tamiasciurus hudsonicus) during 4 years, to measure each female's degree of multiple male mating (MMM), and used an animal model analysis of our multi-generational pedigree to provide what we believe is the first estimate of the heritability of MMM in the wild.

Adopting kin enhances inclusive fitness in asocial red squirrels.

Orphaned animals benefit from being adopted, but it is unclear why an adopting parent should incur the costs of rearing extra young. Such altruistic parental behaviour could be favoured if it is directed towards kin and the inclusive benefits of adoption exceed the costs. Here, we report the occurrence of adoption (five occurrences among 2,230 litters over 19 years) in asocial red squirrels (Tamiasciurus hudsonicus).

The functional response of a hoarding seed predator to mast seeding.

Mast seeding involves the episodic and synchronous production of large seed crops by perennial plants. The predator satiation hypothesis proposes that mast seeding maximizes seed escape because seed predators consume a decreasing proportion of available seeds with increasing seed production. However, the seed escape benefits of masting depend not only on whether predators are satiated at high levels of seed production, but also on the shape of their functional response (type II vs.

Effect of cage-change frequency on rodent breeding performance.

Many people who work in laboratory rodent breeding facilities believe that disrupting certain sensitive rodent lines will result in increased breeding failures and loss of newborn pups. To evaluate this hypothesis, the authors assessed the effect of cage-change frequency on the breeding performances of a mouse strain (C57BL/6NTac) and a rat stock (NTac:NIH-Whn) that were thought to be sensitive to disruption. As per recommendations in the Guide for the Care and Use of Laboratory Animals, personnel changed one half of the breeding cages weekly, regardless of the presence of newborn pups.

Predator-mediated allee effects in multi-prey systems.

Allee effects can have significant consequences for small populations and understanding the causal mechanisms for such effects is important for guiding conservation actions. One proposed mechanism is through predation, in which a type II functional response leads to increasing predation rates as prey numbers decline. However, models to support this mechanism have incorporated only a single declining prey species in the functional response, which is probably an oversimplification.

Fecal cortisol metabolite levels in free-ranging North American red squirrels: Assay validation and the effects of reproductive condition.

Patterns in stress hormone (glucocorticoid: GC) levels and their relationship to reproductive condition in natural populations are rarely investigated. In this study, we (1) validate an enzyme-immunoassay to measure fecal cortisol metabolite (FCM) levels in North American red squirrels (Tamiasciurus hudsonicus), and (2) examine relationships between FCM levels and reproductive condition in a free-ranging red squirrel population. Injected radiolabeled cortisol was entirely metabolized and excreted in both the urine (mean+/-SE; 70.

Helicobacter pullorum outbreak in C57BL/6NTac and C3H/HeNTac barrier-maintained mice.

Helicobacter pullorum is a bacterial pathogen in humans. By using microaerobic culture techniques, H. pullorum was isolated from the feces of barrier-maintained mice and identified, on the basis of biochemical, restriction fragment length polymorphism, and 16S rRNA gene sequence analyses.

Prevalence of serum IgG and neutralizing factors against adeno-associated virus (AAV) types 1, 2, 5, 6, 8, and 9 in the healthy population: implications for gene therapy using AAV vectors.

Adeno-associated viruses (AAVs) are small, nonenveloped single-stranded DNA viruses that require helper viruses to facilitate efficient replication. Despite the presence of humoral responses to the wild-type AAV in humans, AAV remains one of the most promising candidates for therapeutic gene transfer to treat many genetic and acquired diseases. Characterization of the IgG subclass responses to AAV and study of the prevalence of both IgG and neutralizing factors to AAV types 1, 2, 5, 6, 8, and 9 in the human population are of importance for the development of new strategies to overcome these immune responses.

Energetic costs of male reproduction in a scramble competition mating system.

1. The assumption that the primary limitations on reproductive success differ between the sexes is inherent in traditional sexual selection theory. Although the energy that can be allocated to reproduction is assumed to be the main limitation to females, the ability to attract and defend oestrous females is assumed to be the primary limitation to males.

Prospective assessment of pain and functional status after vertebroplasty for treatment of vertebral compression fractures.

Background And Purpose: There has been no prospective evaluation of vertebroplasty using a validated instrument. We describe the pain and functional status of 72 patients before and after vertebroplasty, as prospectively evaluated by the Vertebral Compression Fracture Pain and Functional Disability Questionnaire.

Methods: Of 161 consecutive patients, 72 consented to participate in the study and self-completed the questionnaire prior to undergoing vertebroplasty.

Cytolethal distending toxin promotes Helicobacter cinaedi-associated typhlocolitis in interleukin-10-deficient mice.

Helicobacter cinaedi colonizes a wide host range, including rodents, and may be an emerging zoonotic agent. Colonization parameters, pathology, serology, and inflammatory responses to wild-type H. cinaedi (WT(Hc)) were evaluated in B6.

Highly efficient transduction of human plasmacytoid dendritic cells without phenotypic and functional maturation.

Background: Gene modified dendritic cells (DC) are able to modulate DC functions and induce therapeutic immunity or tolerance in an antigen-specific manner. Among the different DC subsets, plasmacytoid DC (pDC) are well known for their ability to recognize and respond to a variety of viruses by secreting high levels of type I interferon.

Methods: We analyzed here, the transduction efficiency of a pDC cell line, GEN2.

Survival costs of reproduction vary with age in North American red squirrels.

The costs of reproduction are expected to be higher under unfavourable conditions, so that breeding in years of low food supply should have important costs. In addition, the costs of reproduction may be contingent on the age of individuals, and young growing and old senescent individuals should suffer higher costs than the prime-age ones. We tested these predictions by investigating the costs of reproduction as a function of food availability and age in female North American red squirrels using the long-term data on survival and reproduction.

Lactating red squirrels experiencing high heat load occupy less insulated nests.

The heat dissipation limit hypothesis suggests that the capacity for lactating mammals to transfer energy to their offspring through milk may be constrained by limits on heat dissipation, particularly in species that raise offspring in well-insulated nests. We tested a prediction of this hypothesis by evaluating whether lactating free-ranging red squirrels (Tamiasciurus hudsonicus) occupy less insulated nests when experiencing conditions that increase heat load. In support of the hypothesis, when climate normal ambient temperatures were warm, squirrels supporting large litter masses of furred offspring occupied nests of lower insulative value.

Sexually selected behaviour: red squirrel males search for reproductive success.

1. Differential male reproductive success is commonplace in mammals and frequently attributed to variation in morphological traits that provide individuals with a competitive advantage in female defence mating systems. Other mammalian mating systems, however, have received comparatively little attention and correlates of male reproductive success in them are less well understood.

Impacts of chronic anthropogenic noise from energy-sector activity on abundance of songbirds in the boreal forest.

The effects of human activities in forests are often examined in the context of habitat conversion. Changes in habitat structure and composition are also associated with increases in the activity of people with vehicles and equipment, which results in increases in anthropogenic noise. Anthropogenic noise may reduce habitat quality for many species, particularly those that rely on acoustic signals for communication.

The diversity of reproductive parasites among arthropods: Wolbachia do not walk alone.

Background: Inherited bacteria have come to be recognised as important components of arthropod biology. In addition to mutualistic symbioses, a range of other inherited bacteria are known to act either as reproductive parasites or as secondary symbionts. Whilst the incidence of the alpha-proteobacterium Wolbachia is relatively well established, the current knowledge of other inherited bacteria is much weaker.

Plasma DHEA levels in wild, territorial red squirrels: seasonal variation and effect of ACTH.

In many species, territorial behavior is limited to the breeding season and is tightly coupled to circulating gonadal steroid levels. In contrast, both male and female red squirrels (Tamiasciurus hudsonicus) are highly aggressive in both the breeding and non-breeding seasons in defense of food stores on their individual territories throughout the boreal and northern forests of North America. Dehydroepiandrosterone (DHEA), an androgen precursor, is secreted from the adrenal cortex in some mammals, and DHEA has been linked to aggression in non-breeding songbirds.

Genetic susceptibility to chronic hepatitis is inherited codominantly in Helicobacter hepaticus-infected AB6F1 and B6AF1 hybrid male mice, and progression to hepatocellular carcinoma is linked to hepatic expression of lipogenic genes and immune function-associated networks.

Helicobacter hepaticus causes hepatitis in susceptible strains of mice. Previous studies indicated that A/JCr mice are susceptible and C57BL/6NCr mice are resistant to H. hepaticus-induced hepatitis.

Cohort effects in red squirrels: the influence of density, food abundance and temperature on future survival and reproductive success.

1. Environmental conditions experienced early in life may have long-lasting effects on individual performance, thereby creating 'silver-spoon effects'. 2.