There is continuing interest in the trend of costs associated with pollution abatement activities. We specify an environmental production technology to model the joint production of good and bad outputs. The joint production model calculates pollution abatement costs and identifies changes in these costs associated with: (1) technical change, (2)...
BACKGROUND: The relationship between arsenic and birth weight is not well understood.
OBJECTIVE: To evaluate the causal relationship between prenatal arsenic exposure and birth weight considering the potential mediation effects of gestational age (GA) and maternal weight gain (MWG) during pregnancy using structural equation models (SEMs).
METHODS: A prospectively enrolled...
The northern portion of the Pacific coastal temperate rainforest (PCTR) is one of the least anthropogenically modified regions on earth and remains in many respects a frontier area to science. Rivers crossing the northern PCTR, which is also an international boundary region between British Columbia, Canada and Alaska, USA, deliver...
People who become homeless for the first time in late life are a growing but understudied population. This study draws on administrative data from one shelter (N = 1,214 first-time homeless) to assess the extent to which age is related to shelter stay and, to examine psychosocial factors that may...
Background:
Myxozoans are metazoan parasites whose traditional spore morphology-based taxonomy conflicts DNA based phylogenies. Freshwater species of the genus Hoferellus are parasites of the excretory system, with several members infecting food and ornamental fish species, as well as amphibians. This study aims to increase our understanding of their molecular diversity...
Multiple stressors are currently threatening honey bee health, including pests and pathogens. Among honey bee pathogens, Nosema ceranae is a microsporidian found parasitizing the western honey bee (Apis mellifera) relatively recently. Honey bee colonies are fed pollen or protein substitute during pollen dearth to boost colony growth and immunity against...
For marine mammals, the ability to tolerate apnea and make extended dives is a defining adaptive trait, facilitating the exploitation of marine food resources. Elevated levels of myoglobin within the muscles are a consistent hallmark of this trait, allowing oxygen collected at the surface to be stored in the muscles...
Summary 1. Woody plant encroachment of grasslands is occurring globally, with profound ecological consequences. Attempts to restore herbaceous dominance may fail if the woody state is resilient or if intervention leads to an alternate, undesirable state. Restoration outcomes often hinge on biotic interactions – particularly on priority effects that inhibit...
Forested riparian buffers isolate streams from the influence of harvesting operations that can lead to water temperature increases. Only forest cover between the sun and stream limits stream warming, but that cover also reduces instream photosynthesis, aquatic insect production, and fish productivity. Water temperature increases that occur as streams flow...
Here we report a new transgenic expression system by combination of liver-specific expression, mifepristone induction and Cre-loxP recombination to conditionally control the expression of oncogenic kras[superscript]V12. This transgenic system allowed expression of kras[superscript]V12 specifically in the liver by a brief exposure of mifepristone to induce permanent genomic recombination mediated by...