The long duration and strong velocity content of the motions produced by the 27 February 2010 Maule earthquake resulted in widespread liquefaction and lateral spreading in several urban and other regions of Chile. In particular, critical lifeline structures such as bridges, roadway embankments, and railroads were damaged by ground shaking...
Studies were conducted to evaluate the use of several trap-lure combinations to improve the monitoring of codling moth, Cydia pomonella (L.) (Lepidoptera: Tortricidae), in apple, Malus domestica Bordk. The treatments involved the use of clear, orange, and white traps baited with one or more of the following attractants: the major...
Stem sinuosity is a highly visible stem-form trait in the leaders of fast-growing Douglas-fir (Pseudotsuga menziesii var. (Mirb.) Franco) trees, yet its cause is unknown. We tested the hypotheses that sinuous stems have longer expanses of primary growth than nonsinuous stems (putting the leader at higher risk curvature, induction of...
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A simple behavioral test was devised to determine the effects of multiple acute stresses on the avoidance response time of fish. Groups of freshwater-adapted juvenile chinook salmon Oncorhynchus tshawytscha were exposed to a sudden overhead light and the time it took each fish to reach cover was noted. Tests were...
Various methods have been developed to mitigate the adverse effects of the Federal Columbia River Power System on juvenile Pacific salmon out-migrating through the Columbia River basin. In this study, we found that hatchery-reared spring Chinook salmon Oncorhynchus tshawytscha in the river are in varying degrees of health, which may...
Across animal taxa, migration allows individuals to exploit habitats and resources that predictably vary seasonally in suitability. Theory predicts that the ‘‘decision’’ to migrate or not is shaped by the relative fitness costs and benefits of exhibiting a given life history. Adoption of a migratory strategy is widely thought to...
Identification of the factors that influence susceptibility to predation can aid in developing management strategies to recover fish populations of conservation concern. Predator-prey relationships can be influenced by numerous factors, including prey condition, prey size, and environmental conditions. We investigated these factors by using juvenile steelhead Oncorhynchus mykiss from the...
Freshwater discharge affects the biogeochemistry of river-influenced nearshore environments by contributing with carbon and nutrients. An increase in human activities in river basins may alter the natural riverine nutrients and carbon export to coastal ecosystems. Along a wide latitudinal range (32° 55'S-40° 10'S), this study explores the role of climate...
The operation of the Federal Columbia River Power System (FCRPS) has negatively affected threatened and endangered salmonid populations in the Pacific Northwest. Barging Snake River spring Chinook salmon Oncorhynchus tshawytscha through the FCRPS is one effort to mitigate the effect of the hydrosystem on juvenile salmon out-migration. However, little is...
Intercellular transport of viruses through cytoplasmic connections, termed plasmodesmata (PD), is essential for systemic infection in plants by viruses. Previous genetic and ultrastructural data revealed that the potyvirus cyclindrical inclusion (CI) protein is directly involved in cell-to-cell movement, likely through the formation of conical structures anchored to and extended through...
The relationship between predator avoidance deficits induced by a simple handling stress and the level of plasma corticosteroids was determined for juvenile coho salmon Oncorhynchus kisutch. Groups of fish were held out of water for 1 min, then allowed to recover from this stress for 1, 90, or 240 min....
Restriction of long-distance movement of several potyviruses in Arabidopsis (Arabidopsis thaliana) is controlled by at least three
dominant restricted TEV movement (RTM) genes, named RTM1, RTM2, and RTM3. RTM1 encodes a protein belonging to the
jacalin family, and RTM2 encodes a protein that has similarities to small heat shock proteins....
Chile’s open trade policy, implemented during the last few decades, has greatly transformed Chilean farmers and their production systems. As a result, farmers can be grouped into three categories based on their market-production orientation: domestic, transitional or export producers. The objective of this paper is to analyze the factors underlying...
Adult Chinook salmon (Oncorhynchus tshawytscha) migrate from salt water to freshwater streams to spawn. Immune responses in migrating adult salmon are thought to diminish in the run up to spawning, though the exact mechanisms for diminished immune responses remain unknown. Here we examine both adaptive and innate immune responses as...
Re-introduction of California condors into Oregon is currently being considered,
but there are concerns about the safety of potential food sources of this species.
Condors are opportunistic feeders and a largely available food source for this
species will be stranded marine mammal carcasses. We analyzed 37 blubber
samples from 7...
Previous studies have shown that juvenile chinook salmon Oncorhynchus tshawytscha exposed in the field or the laboratory to polychlorinated biphenyls (PCBs), an anthropogenic stressor, are immunosuppressed. It is not known whether simultaneous exposure to natural stressors can increase this immunosuppression. To examine the effects of natural and anthropogenic stressors on...
We examined 1454 juvenile Chinook salmon, Oncorhynchus tshawytscha (Walbaum), captured in nearshore waters off the coasts of Washington and Oregon (USA) from 1999 to 2004 for infection by Renibacterium salmoninarum, Nanophyetus salmincola Chapin and skin metacercariae. The prevalence and intensities for each of these infections were established for both yearling...
The freshwater trematode Nanophyetus salmincola has been demonstrated to impair salmonid immune function and resistance to the marine pathogen Vibrio anguillarum, potentially resulting in ocean mortality. We examined whether infection by the parasite N. salmincola similarly increases mortality of juvenile Chinook Salmon Oncorhynchus tshawytscha when they are exposed to the...
The sablefish Anoplopoma fimbria is a valuable North Pacific Ocean species that, when not targeted in various commercial fisheries, is often a part of discarded bycatch. Predictions of the survival of discarded fish are dependent on understanding how a fish responds to stressful conditions. Our objective was to describe the...
MicroRNAs (miRNAs) are an extensive class of noncoding genes that regulate gene expression through
posttranscriptional repression. Given the potential for large viral genomes to encode these transcripts, we
examined the human cytomegalovirus AD169 genome for miRNAs using a bioinformatics approach. We
identified 406 potential stem-loops, of which 110 were conserved...
The genetic structure of adult codling moth, Cydia pomonella (L.), populations was characterized both inside a managed apple, Malus domestica Borkdhausen, orchard and in surrounding unmanaged hosts and nonhost trees in central Chile during 2006–2007. Adult males were collected using an array of sex pheromone-baited traps. Five microsatellite genetic markers...
A great deal of research has documented racial disparities in imprisonment rates in the United States, but little work has been done to understand the process by which inmates are assigned to individual correctional facilities. This article extends research on racial disparities in imprisonment rates to consider racial disparities in...
We recovered passive integrated transponder (PIT) tags from nine piscivorous waterbird colonies in the Columbia River basin to evaluate avian predation on Endangered Species Act (ESA)-listed salmonid Oncorhynchus spp. populations during 2007–2010. Avian predation rates were calculated based on the percentage of PIT-tagged juvenile salmonids that were detected as passing...
A mutational analysis was conducted to investigate the functions of the tobacco etch potyvirus VPgproteinase
(NIa) protein in vivo. The NIa N-terminal domain contains the VPg attachment site, whereas the
C-terminal domain contains a picornavirus 3C-like proteinase. Cleavage at an internal site separating the two
domains occurs in a subset...
Plum pox virus (PPV) is a member of the Potyvirus genus that, in nature, infects trees of the Prunus genus.
Although PPV infects systemically several species of the Nicotiana genus, such as N. clevelandii and N.
benthamiana, and replicates in the inoculated leaves of N. tabacum, it is unable to...
Understanding how individual characteristics are associated with survival is important to programs aimed at recovering
fish populations of conservation concern. To evaluate whether individual fish characteristics observed during
the juvenile life stage were associated with the probability of returning as an adult, juvenile steelhead Oncorhynchus
mykiss from two distinct population...
Multicellular eukaryotes produce small RNA molecules (approximately 21–24 nucleotides) of two general types, microRNA (miRNA) and short interfering RNA (siRNA). They collectively function as sequence-specific guides to silence or regulate genes, transposons, and viruses and to modify chromatin and genome structure. Formation or activity of small RNAs requires factors belonging...
Because ocean circulation impacts global heat transport, understanding the relationship between deep ocean circulation and climate is important for predicting the ocean's role in climate change. A common approach to reconstruct ocean circulation patterns employs the neodymium isotope compositions of authigenic phases recovered from marine sediments. In this approach, mild...
Anthropogenic modification watersheds and climate change have altered export from fluvial systems causing changes to the carbonate chemistry of river-influenced near shore environments. To determine the possible effects of riverine discharges on the mussel Perumytilus purpuratus, we performed in situ transplant experiments between river-influenced and open coastal habitats with contrasting...
Maximum earthquake magnitude (m[subscript x]) is a critical parameter in seismic
hazard and risk analysis. However, some recent large earthquakes have shown that
most of the existing methods for estimating m[subscript x] are inadequate. Moreover, m[subscript x] itself is ill-defined because its meaning largely depends on the context, and it...