Cardiovascular responses to putative chemoreceptor stimulation of embryonic common snapping turtles (Chelydra serpentina) chronically incubated in hypoxia (10% O).

Developmental hypoxia has been shown to result in significant changes in cardiovascular development of American alligators and common snapping turtles. These include similar effects on cardiac mass and aspects of cardiovascular function. However, given the distant phylogenetic relationship between crocodilians and chelonians, we hypothesized that snapping turtles would also exhibit differences in the effects of developmental hypoxia on cardiovascular regulation.

Lipid oxidation during thermogenesis in high-altitude deer mice ().

When at their maximum thermogenic capacity (cold-induced V̇o), small endotherms reach levels of aerobic metabolism as high, or even higher, than running V̇o. How these high rates of thermogenesis are supported by substrate oxidation is currently unclear. The appropriate utilization of metabolic fuels that could sustain thermogenesis over extended periods may be important for survival in cold environments, like high altitude.

Coordinated changes across the O transport pathway underlie adaptive increases in thermogenic capacity in high-altitude deer mice.

Animals native to the hypoxic and cold environment at high altitude provide an excellent opportunity to elucidate the integrative mechanisms underlying the adaptive evolution and plasticity of complex traits. The capacity for aerobic thermogenesis can be a critical determinant of survival for small mammals at high altitude, but the physiological mechanisms underlying the evolution of this performance trait remain unresolved. We examined this issue by comparing high-altitude deer mice () with low-altitude deer mice and white-footed mice ().

Mitigating Methane: Emerging Technologies To Combat Climate Change's Second Leading Contributor.

Methane (CH) is the second greatest contributor to anthropogenic climate change. Emissions have tripled since preindustrial times and continue to rise rapidly, given the fact that the key sources of food production, energy generation and waste management, are inexorably tied to population growth. Until recently, the pursuit of CH mitigation approaches has tended to align with opportunities for easy energy recovery through gas capture and flaring.

Chronic captopril treatment reveals the role of ANG II in cardiovascular function of embryonic American alligators (Alligator mississippiensis).

Angiotensin II (ANG II) is a powerful vasoconstrictor of the renin-angiotensin system (RAS) that plays an important role in cardiovascular regulation in adult and developing vertebrates. Knowledge of ANG II's contribution to developmental cardiovascular function comes from studies in fetal mammals and embryonic chickens. This is the first study to examine the role of ANG II in cardiovascular control in an embryonic reptile, the American alligator (Alligator mississippiensis).

Cardiovascular adjustments with egg temperature at 90% incubation in embryonic American alligators, Alligator mississippiensis.

American alligators (Alligator mississippiensis) deposit eggs in a mound nest, potentially subjecting embryos to daily variations in temperature. Whilst adult crocodilian cardiovascular responses to changes in temperature have been investigated, similar studies in alligator embryos are limited. We investigated cardiovascular function of embryonic alligators during heating and cooling as well as at different temperatures.

Crying in psychotherapy: The perspective of therapists and clients.

Eighteen U.S.-based doctoral students in counseling or clinical psychology were interviewed by phone regarding experiences of crying in therapy.

Circulatory mechanisms underlying adaptive increases in thermogenic capacity in high-altitude deer mice.

We examined the circulatory mechanisms underlying adaptive increases in thermogenic capacity in deer mice () native to the cold hypoxic environment at high altitudes. Deer mice from high- and low-altitude populations were born and raised in captivity to adulthood, and then acclimated to normoxia or hypobaric hypoxia (simulating hypoxia at ∼4300 m). Thermogenic capacity [maximal O consumption (), during cold exposure] was measured in hypoxia, along with arterial O saturation (a ) and heart rate ().

Biogas production from steer manures in Vietnam: Effects of feed supplements and tannin contents.

In developing countries, the simple biogas digesters installed underground without heating or stirring are seen as a 'green' technology to convert animal waste into biogas, a source of bio-energy. However, quantitative estimates of biogas production of manures from steers fed local feed diets at actual incubation temperatures have yet to be carried out. The aim of this study was to determine the methane (CH) production potential of manures from steers in Vietnam offered traditional feed rations or supplemental diets.

Assessing the Performance of Floating Biofilters for Oxidation of Methane from Dairy Effluent Ponds.

Mitigating methane (CH) emissions from New Zealand dairy effluent ponds using volcanic pumice soil biofilters has been found to be a promising technology. Because the soil column biofilter prototype previously used was cumbersome, here we assess the effectiveness of volcanic pumice soil-perlite biofilter media in a floating system to remove high concentrations of CH emitted from a dairy effluent pond and simultaneously in a laboratory setting. We measured the CH removal over a period of 11 mo and determined methanotroph population dynamics using molecular techniques to understand the role of methanotroph population abundance and diversity in CH removal.

Assessment of farm soil, biochar, compost and weathered pine mulch to mitigate methane emissions.

Previous studies have demonstrated the effective utility of volcanic pumice soil to mitigate both high and low levels of methane (CH) emissions through the activity of both γ-proteobacterial (type I) and α-proteobacterial (type II) aerobic methanotrophs. However, the limited availability of volcanic pumice soil necessitates the assessment of other farm soils and potentially suitable, economical and widely available biofilter materials. The potential biofilter materials, viz.

Periods of cardiovascular susceptibility to hypoxia in embryonic american alligators (Alligator mississippiensis).

During embryonic development, environmental perturbations can affect organisms' developing phenotype, a process known as developmental plasticity. Resulting phenotypic changes can occur during discrete, critical windows of development. Critical windows are periods when developing embryos are most susceptible to these perturbations.

Matches, Mismatches, and Methods: Multiple-View Workflows for Energy Portfolio Analysis.

The energy performance of large building portfolios is challenging to analyze and monitor, as current analysis tools are not scalable or they present derived and aggregated data at too coarse of a level. We conducted a visualization design study, beginning with a thorough work domain analysis and a characterization of data and task abstractions. We describe generalizable visual encoding design choices for time-oriented data framed in terms of matches and mismatches, as well as considerations for workflow design.

Critical Windows of Cardiovascular Susceptibility to Developmental Hypoxia in Common Snapping Turtle (Chelydra serpentina) Embryos.

Environmental conditions fluctuate dramatically in some reptilian nests. However, critical windows of environmental sensitivity for cardiovascular development have not been identified. Continuous developmental hypoxia has been shown to alter cardiovascular form and function in embryonic snapping turtles (Chelydra serpentina), and we used this species to identify critical periods during which hypoxia modifies the cardiovascular phenotype.

Development of adrenergic and cholinergic receptor cardiovascular regulatory capacity in the Canada goose (Branta canadensis) and domestic goose (Anser anser domesticus).

Adrenergic control of cardiovascular function is a common component of regulation in embryonic birds studied to date. Our goal was to investigate adrenergic and cholinergic cardiovascular regulation in two goose species, the Canada goose (Branta canadensis) and the related domestic goose (Anser anser domesticus) to determine if these species possess similar regulation during embryonic development. We determined mean arterial pressure (Pm) and heart rate (fH) responses to serial blockade of cholinergic, β-adrenergic and α-adrenergic receptors in B.

Plasticity of cardiovascular function in snapping turtle embryos (Chelydra serpentina): chronic hypoxia alters autonomic regulation and gene expression.

Reptile embryos tolerate large decreases in the concentration of ambient oxygen. However, we do not fully understand the mechanisms that underlie embryonic cardiovascular short- or long-term responses to hypoxia in most species. We therefore measured cardiac growth and function in snapping turtle embryos incubated under normoxic (N21; 21% O₂) or chronic hypoxic conditions (H10; 10% O₂).

Quantifying the climate-change consequences of shifting land use between forest and agriculture.

Land-use change between forestry and agriculture can cause large net emissions of carbon dioxide (CO2), and the respective land uses associated with forest and pasture lead to different on-going emission rates of methane (CH4) and nitrous oxide (N2O) and different surface albedo. Here, we quantify the overall net radiative forcing and consequent temperature change from specified land-use changes. These different radiative agents cause radiative forcing of different magnitudes and with different time profiles.

Testing a biofilter cover design to mitigate dairy effluent pond methane emissions.

Biofiltration, whereby CH(4) is oxidized by methanotrophic bacteria, is a potentially effective strategy for mitigating CH(4) emissions from anaerobic dairy effluent lagoons/ponds, which typically produce insufficient biogas for energy recovery. This study reports on the effectiveness of a biofilter cover design at oxidizing CH(4) produced by dairy effluent ponds. Three substrates, a volcanic pumice soil, a garden-waste compost, and a mixture of the two, were tested as media for the biofilters.

CH4/CO2 ratios indicate highly efficient methane oxidation by a pumice landfill cover-soil.

Landfills that generate too little biogas for economic energy recovery can potentially offset methane (CH(4)) emissions through biological oxidation by methanotrophic bacteria in cover soils. This study reports on the CH(4) oxidation efficiency of a 10-year old landfill cap comprising a volcanic pumice soil. Surface CH(4) and CO(2) fluxes were measured using field chambers during three sampling intervals over winter and summer.

Effects of dehydration on cardiovascular development in the embryonic American alligator (Alligator mississipiensis).

Effects of dehydration on reptilian embryonic cardiovascular function are unknown. Here, we present the first morphological and physiological data quantifying the cumulative effects of four acute dehydration events on the embryonic American alligator, Alligator mississipiensis. We hypothesized that dehydration would alter embryonic morphology, reduce blood volume and augment the response to angiotensin II (Ang II), a key osmotic and blood volume regulatory response element in adult vertebrates.

In vitro methane removal by volcanic pumice soil biofilter columns over one year.

Soil methane (CH(4)) biofilters, containing CH(4)-oxidizing bacteria (methanotrophs), are a promising technology for mitigating greenhouse gas emissions. However, little is known about long-term biofilter performance. In this study, volcanic pumice topsoils (0-10 cm) and subsoils (10-50 cm) were tested for their ability to oxidize a range of CH(4) fluxes over 1 yr.

Response of methanotrophic communities to afforestation and reforestation in New Zealand.

Methanotrophs use methane (CH(4)) as a carbon source. They are particularly active in temperate forest soils. However, the rate of change of CH(4) oxidation in soil with afforestation or reforestation is poorly understood.

Biochemical and molecular characterization of methanotrophs in soil from a pristine New Zealand beech forest.

Methane (CH4) oxidation and the methanotrophic community structure of a pristine New Zealand beech forest were investigated using biochemical and molecular methods. Phospholipid-fatty acid-stable-isotope probing (PLFA-SIP) was used to identify the active population of methanotrophs in soil beneath the forest floor, while terminal-restriction fragment length polymorphism (T-RFLP) and cloning and sequencing of the pmoA gene were used to characterize the methanotrophic community. PLFA-SIP suggested that type II methanotrophs were the predominant active group.

Effect of afforestation and reforestation of pastures on the activity and population dynamics of methanotrophic bacteria.

We investigated the effect of afforestation and reforestation of pastures on methane oxidation and the methanotrophic communities in soils from three different New Zealand sites. Methane oxidation was measured in soils from two pine (Pinus radiata) forests and one shrubland (mainly Kunzea ericoides var. ericoides) and three adjacent permanent pastures.