We reconstructed oxygenation changes in the upwelling ecosystem off Concepción (36° S), Chile, using inorganic and organic proxies in a sediment core covering the last ca. 110 years of sedimentation in this area. Authigenic enrichments of Mo, U and Cd were observed between ca. 1935 and 1971 CE, implying a...
We reconstructed oxygenation changes in the Oxygen Minimum Zone of the upwelling ecosystem off Concepción (36° S), Chile, using inorganic and organic proxies in a sediment core covering the last ca. 110 years of sedimentation in this area. Authigenic enrichments of Mo, U and Cd were observed between ca. 1935–1971...
In 2 consecutive years, ground beetles (Coleoptera: Carabidae) were sampled in commercial organic and conventional potato fields, using pit fall traps. Four conventional and 3 organic potato fields were surveyed to determine ground beetle taxa composition. In a related study, potato fields were assigned to 1 of 4 transitional systems...
Lamon Bay is one of the most important fishing grounds in the Philippines. In spite of this, most fishermen in the area live in poverty, and their plight is getting worse, not better. Fish catch is declining by 13.5 % a year, more than double the decline experienced elsewhere in...
Through application of carbon (C) and nitrogen (N) stable isotope analyses, we investigated the benthic trophic structure of
the upper-slope off southern Chile (~45°S) including a recent methane seep area discovered as part of this study. The observed
fauna comprised 53 invertebrates and seven fish taxa, including remains of chemosymbiotic...
Freshwater systems cycle carbon along a spatial and temporal biogeochemical continuum, across which ecosystem processes contribute to transformations of organic matter (OM). Various ecological constraints impact rates OM transformation and production and consumption of the energetic end of respiration, methane. Microbiological processing and complete reduction of carbon substrates to methane...
Scientists and land managers realize that integrated weed management (IWM) strategies are needed to attain successful and lasting improvements of weed infested landscapes. At this time no broadly reliable and environmentally safe IWM strategy has been developed to control exotic annual grasses that dominate many ecosystems of the northern Great...
Soil nitrogen exists largely as organic matter, including plant liter, dead animal matter, and microbial necromass. About 90% of soil organic nitrogen is proteinaceous material that is too large for plants and microorganisms to assimilate directly. Protein depolymerization therefore plays a critical role in mobilizing this organic source of nitrogen,...
Proteinaceous compounds are abundant forms of organic nitrogen in soil and aquatic ecosystems, and the rate of protein depolymerization, which is accomplished by a diverse range of microbial secreted peptidases, often limits nitrogen turnover in the environment. To determine if the distribution of secreted peptidases reflects the ecological and evolutionary...
Several experiments involving broilers and laying hens
were conducted to study the effects of feeding crab meal,
dried whey and cellulose. The positive responses of crab
meal as a substance for improving the utilization of dried
whey and cellulose were examined. Cellulose treated with
concentrated H3PO4 in broiler diets and...
Cell death is a process of dying within biological cells that are ceasing to function. This process is essential in regulating organism development, tissue homeostasis, and to eliminate cells in the body that are irreparably damaged. In general, dysfunction in normal cellular death is tightly linked to cancer progression. Specifically,...
Sediments of the central Chile margin record changes in ocean circulation and
continental erosion associated with large–scale climate change. Here Antarctic–
influenced Southern Ocean currents flow equatorward, forming a link between the high–
and low–latitude oceans. Part of this link, Antarctic Intermediate Water, is an important
conduit that ventilates South...
The dairy industry has indicated that milk hauling sporadically compromises milk quality, but often the reason is unknown. Milk hauling practices are an underexplored area of research, and are in need of attention because during hauling milk is most exposed to the external environment in comparison with any other step...
The release of marine debris into the oceans and seas is a global issue of growing concern. These materials are harmful to marine environments and can also transport non-native species to novel habitats. Non-native species floating on marine litter is one of the lesser known impacts associated with marine debris....
Faculty and librarians agree on the qualities of a good research question. However, in an exploratory study, they differed on when students should develop their research question. While librarians stated that students should develop their question early, first-year writing faculty advocated for delaying the development of the research question. The...
Bees play a crucial role in pollinating crops, supporting biodiversity, and maintaining ecosystem health. Despite their importance, the decline in bee populations has become a global concern due to various factors including habitat loss, urbanization, and climate change. The purpose of this thesis is to write an article that highlights...
The European green crab (Carcinus maenas) has persisted in Oregon and Washington coastal estuaries since the late 1990s. A strong year class arrived during the 1998 El Niño, but numbers decreased and remained below 1 per trap per day until the arrival of the 2015-2016 El Niño. Since then, numbers...
Climate regime shifts force fish communities through rapid transitions between alternate species assemblages, but little is known about the role that biochemical ecology plays in these transitions. We document a biochemical effect of climate-induced community transitions in boreal oceans: opposite population trajectories of lipid-rich and lipid-poor fish species. We compared...
Recruitment of larvae from the plankton is an important determinant of
community structure in marine systems. In populations of many marine species,
recruitment determines the basic demographic parameters of immigration, emigration,
and reproduction. Moreover, the effect of recruitment as an "ecological subsidy" can
determine the strength of interactions among species...
The impact of organic fertilizer source on the growth, fruit quality, and yield of blackberry (Rubus L. subgenus Rubus Watson) cultivars (Marion and Black Diamond) grown in a machine-harvested, organic production system for the processed market was evaluated from 2011 to 2013. The planting was established in Spring 2010 using...
The diverse community of bacteria living within and on host organisms, known as the microbiome, has an important role in maintaining host health. Dysbiosis, known as a change in the healthy community of the microbiome, has been associated with a number of diseases across host organisms and body sites including...
Sediments associated with hydrothermal venting, methane seepage and large organic falls such as whale, wood and plant detritus create deep-sea networks of soft-sediment habitats fueled, at least in part, by the oxidation of reduced chemicals. Biological studies at deep-sea vents, seeps and organic falls have looked at macrofaunal taxa, but...
The impact of fertilizer source and cultivar on growth, fruit quality, and yield was evaluated in organic blackberry (Rubus L. subgenus Rubus Watson) from 2011-2013 in three studies. In all studies, plants were drip irrigated, and weeds were managed using a woven polypropylene, permeable landscape fabric (weed mat). At a...
One of the most extensive Chilean health care reforms occurred in July 2005, when the Regime of Explicit Health Guarantees (AUGE) became effective. This reform guarantees coverage for a specific set of health conditions. Thus, the purpose of this study is to provide timely evidence for policy makers to understand...
Microplastics, plastic marine debris less than 5 mm in size, is a threat to the health of our oceans. One important way to reduce microplastics in our oceans is to educate people about the issue, particularly future decision-makers. In this study, a middle school curriculum was developed using current scientific...
The Columbia River delivers the greatest amount of freshwater to the coastal ocean along the U.S. Pacific coast. This freshwater forms the Columbia River plume, a mesoscale plume with significant implications on coastal ocean physical, biological, chemical, and geological processes. The plume is transported south and offshore during the upwelling...
To users, mobile touchscreen devices have appealing characteristics; among these characteristics is intuitiveness, which leads to mobile devices being used almost everywhere by almost everyone to accomplish almost anything. This statement, to some degree, holds for children too. Despite touchscreen devices’ intuitiveness and popularity, we don’t know much about how...
In 2016, the Oregon Community Foundation reported that twelve percent of Latinx folks graduated with their bachelor’s and/or master’s degree compared to the 31 percent of White counterparts (Latinos in Oregon Report, 2016). While Latinx students continue to be the largest minority in the United States, Latinx students enroll in...
The high productivity of Eastern Boundary Upwelling Ecosystems (EBUE), some of the most productive ecosystems in the globe, is attributed to the nutrient rich waters brought up through upwelling. Climate change scenarios for coastal upwelling systems, predict an intensification of coastal upwelling winds. Associated with intensification in upwelling are biogeochemical...
Chlamydia is an obligate intracellular bacterial pathogen that causes a variety of disease in animals and humans worldwide. Veterinary chlamydial pathogens can lead to chronic infections and serious consequences that result in millions of dollars of losses in animals and resources in the agricultural industry in countries that rear ruminants....
Ian Angell, in the New Barbarian Manifesto, said “A ‘brave new world’ is being forced upon unsuspecting societies by advances in information technology.” It would seem then, that technological advances happen automatically and have a life of their own. There is a logic to technological advancements that is outside human...
There is significant interest in harnessing the biosynthetic capacities of photosynthetic diatom microalgae for the production of unique bioinspired nanomaterials. Specifically, this research focuses on understanding the photoluminescent properties of diatom biosilica and β-chitin nanofiber production in diatoms. Diatoms are single-celled microalgae that possess intricately patterned biosilica shells called, frustules....
A major factor in the ability of Pseudomonas fluorescens Pf-5 to act as a biological control agent is its production of antibiotics, including pyoluteorin (PLT), 2,4-diacetylphloroglucinol (2,4-DAPG) and pyrrolnitrin (PRN). The data provided in this thesis demonstrate that the presence of any of these antibiotics in the extracellular milieu affects...
Nutrigenomics is a branch of nutrition that seeks to elucidate the relationship between dietary components and expression of genes. Certain bioactive compounds present in the diet have the potential to modulate transcription of genes through their interactions with ligand-dependent nuclear receptors, a series of transcriptional regulators capable of sensing intracellular...
European hazelnut (Corylus avellana L.) is an important crop Oregon's Willamette Valley, producing 99% of the hazelnuts grown in North America and brings over US $60 million dollars to the region annually. Hazelnuts are rich in fiber and vitamins, as well in demand by consumers due to their popularity as...