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Molecular characterization and tracking of dissolved organic nitrogen supplied by submarine groundwater to the Gulf of Mexico
No full textDissolved organic nitrogen (DON) plays an important role as a major nitrogen reservoir in the nitrate depleted West Florida Shelf (WFS) of the Gulf of Mexico (GOM). Sources of “new” or export production DON in the GOM have largely been attributed to riverine inputs, but submarine groundwater discharge (SGD) has become a target source of interest for explaining anomalies in mass and isotopic nitrogen budgets. However, disentangling the sources and sinks of allochthonous DON remain challenging due to complex dynamics, low concentrations, and significant background from persistent refractory marine DON. Here, we describe a new approach for characterizing the molecular composition of marine DON. Solid phase extracts of DON are analyzed by liquid chromatography with high field orbitrap mass spectrometry. Data analysis pipelines developed in CoreMS are used to assign molecular formula to detected masses across retention time windows, and these molecular ‘features’ are clustered based on spatial distribution to define molecularly distinct fractions of DON that can be attributed to different supply processes. We report comparisons of the molecular composition of DON throughout depth profiles and surface waters in the West Florida Shelf (WFS) from two cross-sectional cruises in the GOM, as well as coastal boundary fluxes in the form of rivers and SGD from coastal wells. Short-lived and long-lived radium isotope measurements were used as tracers for SGD. Our LCMS analysis results demonstrate that DON sourced from SGD has a distinct composition from DON generated by surface ocean production or persistent refractory DON found at all depths across the GOM. These molecular approaches provide a tracer of SGD sourced DON that can be tracked across the WFS and help constrain the role of SGD in supplying bioavailable nitrogen to coastal marine ecosystems
Kilchis and Miami River Basins master plan for angler access and associated recreational uses
No full textThis report details a plan that we hope can be followed to solve the access problems of the Kilchis and Miami River Basins. Too, we hope that all agencies that are interested in retaining existing water access as well as providing additional facilities, whether they be municipal, county, or state will all join in a cooperative effort to carry out this plan in an orderly manner. It is probable that Land and Water Conservation Funds will be available on a 50-50 matching basis. In order to acquire these funds, it will be.necessary- to apply through the Oregon State Highway Department
Use of Cardiac Gated Computed Tomography in the Diagnosis of a Rare Congenital Cardiovascular Anomaly in an Adult Alpaca
No full textA 5-year-old female alpaca was presented with respiratory distress and lethargy. Thoracic radiographs revealed a cranioventrally distributed alveolar pattern, caudodorsal bronchial pattern, cardiomegaly, increased soft tissue opaque content in the ventral thorax, and rounded soft tissue opaque structures craniodorsal to the carina. Cardiac gated CT demonstrated a patent ductus arteriosus, ventricular septal defect, complete left atrioventricular valve atresia, partial anomalous venous connections from the cranial pulmonary veins to the azygous and cranial vena cava, severe right-sided cardiomegaly, pleural and peritoneal fluid, and severe hepatic congestion. These findings were confirmed with necropsy
A Microchannel Heat Exchanger Produced From a Metal Matrix Composite by Hybrid Laser Powder Bed Fusion and Inkjet Printing
No full textThis paper explores the production of an oxide dispersion strengthened (ODS) 304L stainless steel microchannel heat exchanger (HX) using a hybrid additive manufacturing process of laser powder bed fusion and inkjet printing. The study investigates the capabilities and economics of the hybrid inkjet-laser powder bed fusion (LPBF) process and evaluates the dimensional accuracy, functionality, and mechanical properties of the resulting ODS alloy. The effectiveness and pressure drop of the ODS heat exchangers produced by the hybrid LPBF tool are also determined. Results show that the inkjet-doped samples have a lower mean channel height with higher standard deviation than samples produced by LPBF alone. This is attributed to greater absorption of laser energy for the powder coated with the oxide precursor. The economic analysis shows that the hybrid process has a potential for reducing the unit cost of the heat exchanger based on cost modeling assumptions
Cereal breeding and nursery investigations at the Sherman Branch Experiment Station, Moro, Oregon : 1946
No full textAnnual report Pendleton Branch Experiment Station, Pendleton, Oregon : 1948
No full textIncomplete with partial pages; best version available
