7 research outputs found
Seafloor incubation experiment with deep-sea hydrothermal vent fluid reveals effect of pressure and lag time on autotrophic microbial communities
© The Author(s), 2021. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Fortunato, C. S., Butterfield, D. A., Larson, B., Lawrence-Slavas, N., Algar, C. K., Zeigler Allen, L., Holden, J. F., Proskurowski, G., Reddington, E., Stewart, L. C., Topçuoğlu, B. D., Vallino, J. J., & Huber, J. A. Seafloor incubation experiment with deep-sea hydrothermal vent fluid reveals effect of pressure and lag time on autotrophic microbial communities. Applied and Environmental Microbiology, 87, (2021): e00078-21, https://doi.org/10.1128/AEM.00078-21Depressurization and sample processing delays may impact the outcome of shipboard microbial incubations of samples collected from the deep sea. To address this knowledge gap, we developed a remotely operated vehicle (ROV)-powered incubator instrument to carry out and compare results from in situ and shipboard RNA stable isotope probing (RNA-SIP) experiments to identify the key chemolithoautotrophic microbes and metabolisms in diffuse, low-temperature venting fluids from Axial Seamount. All the incubations showed microbial uptake of labeled bicarbonate primarily by thermophilic autotrophic Epsilonbacteraeota that oxidized hydrogen coupled with nitrate reduction. However, the in situ seafloor incubations showed higher abundances of transcripts annotated for aerobic processes, suggesting that oxygen was lost from the hydrothermal fluid samples prior to shipboard analysis. Furthermore, transcripts for thermal stress proteins such as heat shock chaperones and proteases were significantly more abundant in the shipboard incubations, suggesting that depressurization induced thermal stress in the metabolically active microbes in these incubations. Together, the results indicate that while the autotrophic microbial communities in the shipboard and seafloor experiments behaved similarly, there were distinct differences that provide new insight into the activities of natural microbial assemblages under nearly native conditions in the ocean.This work was funded by Gordon and Betty Moore Foundation grant GBMF3297; the NSF Center for Dark Energy Biosphere Investigations (C-DEBI) (OCE-0939564), contribution number 562; NOAA/PMEL, contribution number 5182; and the Joint Institute for the Study of the Atmosphere and Ocean (JISAO) under NOAA cooperative agreement NA15OAR4320063, contribution number 2020-1113. The RNA-SIP methodology used in this work was developed during cruise FK010-2013 aboard the R/V Falkor supported by the Schmidt Ocean Institute. The NOAA/PMEL supported this work with ship time in 2014 and through funding to the Earth Ocean Interactions group. NSF provided ship time for the 2015 expedition through OCE-1546695 to D.A.B. and OCE-1547004 to J.F.H
Marketing and marketability analysis for the National Museum of Costa Rica.
"Marketing and Marketability Study for the Museo Nacional de Costa Rica" is a continuation of a report completed last year at the Museo Nacional de Costa Rica. That report "Mapping and Market Analysis for the Museo Nacional de Costa Rica" conducted an internal study of the Museo Nacional focusing on visitor response. This report moves outside of the Museo Nacional and looks at public awareness of and interest in the Museo Nacional, focusing on the San Jose tourist population. As part of this report, we conducted a survey of foreign tourists as well as a survey of tourist agencies in the San Jose area. We then analyzed the data from those surveys and made recommendations on a marketing strategy for the Museo Nacional. The market strategy discusses improvements to the marketing as well as the marketability of the Museo Nacional de Costa Rica
Design prototype of a gait patterning device
The purpose of this project was to design, develop, and test a prototype device to be used in the rehabilitation of lower limbs. The prototype mimics the motion of walking through the use of a fourbar linkage driven by a geared permanent magnet D.C. motor. The prototype targets persons suffering from injuries to the nervous system or from neuromuscular diseases such that they do not suffer from mental impairment. The mechanism was designed to supplement current physical therapy methods, eliminating the need for a therapist to manually pattern a patient's leg muscles. A gait sensor system was developed in conjunction with the device in order to measure a patient's progress over time. Design considerations of the device and the sensor system included safety, functionality, comfort, and psychological impact
Sea Surface Salinity Variability in the Bering Sea in 2015–2020
Salinity in the Bering Sea is vital for the physical environment that is tied to the productive ecosystem and the properties of Pacific waters transported to the Arctic Ocean. Its salinity variability reflects many fundamental processes, including sea ice formation/melting and river runoff, but its spatial and temporal characteristics require better documentation. This study utilizes remote sensing products and in situ observations collected by saildrone missions to investigate Sea Surface Salinity (SSS) variability. All Satellite products resolve the large-scale pattern set up by the relatively salty deep basin and the fresh coastal region, but they can be inaccurate near the ice edge and near land. The SSS annual cycle exhibits seasonal maxima in winter to spring, and minima in summer to fall. The amplitude and timing of the seasonal cycle are variable, especially on the eastern Bering Sea shelf. SSS variability recorded by both saildrone, and satellite instruments provide unprecedented insights into short-term oceanic processes including sea ice melting, wind-driven currents during weather events, and river plumes etc. In particular, the Soil Moisture Active Passive (SMAP) satellite demonstrates encouraging skills in capturing the freshening signals induced by spring sea ice melting. The Yukon River plume is another source of intense SSS variability. Surface wind forcing plays an essential role in controlling the horizontal movement of plume water and thereby shaping the SSS seasonal cycle in local regions
Sea Surface Salinity Variability in the Bering Sea in 2015–2020
Salinity in the Bering Sea is vital for the physical environment that is tied to the productive ecosystem and the properties of Pacific waters transported to the Arctic Ocean. Its salinity variability reflects many fundamental processes, including sea ice formation/melting and river runoff, but its spatial and temporal characteristics require better documentation. This study utilizes remote sensing products and in situ observations collected by saildrone missions to investigate Sea Surface Salinity (SSS) variability. All Satellite products resolve the large-scale pattern set up by the relatively salty deep basin and the fresh coastal region, but they can be inaccurate near the ice edge and near land. The SSS annual cycle exhibits seasonal maxima in winter to spring, and minima in summer to fall. The amplitude and timing of the seasonal cycle are variable, especially on the eastern Bering Sea shelf. SSS variability recorded by both saildrone, and satellite instruments provide unprecedented insights into short-term oceanic processes including sea ice melting, wind-driven currents during weather events, and river plumes etc. In particular, the Soil Moisture Active Passive (SMAP) satellite demonstrates encouraging skills in capturing the freshening signals induced by spring sea ice melting. The Yukon River plume is another source of intense SSS variability. Surface wind forcing plays an essential role in controlling the horizontal movement of plume water and thereby shaping the SSS seasonal cycle in local regions
Robust Sensor for Extended Autonomous Measurements of Surface Ocean Dissolved Inorganic Carbon
Ocean carbon monitoring
efforts have increased dramatically in
the past few decades in response to the need for better marine carbon
cycle characterization. Autonomous pH and carbon dioxide (CO<sub>2</sub>) sensors capable of yearlong deployments are now commercially available;
however, due to their strong covariance, this is the least desirable
pair of carbonate system parameters to measure for high-quality, in
situ, carbon-cycle studies. To expand the number of tools available
for autonomous carbonate system observations, we have developed a
robust surface ocean dissolved inorganic carbon (DIC) sensor capable
of extended (>year) field deployments with a laboratory determined
uncertainty of ±5 μmol kg<sup>–1</sup>. Results
from the first two field tests of this prototype sensor indicate that
measurements of DIC are ∼90% more accurate than estimates of
DIC calculated from contemporaneous and collocated measurements of
pH and CO<sub>2</sub>. The improved accuracy from directly measuring
DIC gives rise to new opportunities for quantitative, autonomous carbon-cycle
studies
DataSheet_1_Surface ocean warming near the core of hurricane Sam and its representation in forecast models.docx
On September 30, 2021, a saildrone uncrewed surface vehicle intercepted Hurricane Sam in the northwestern tropical Atlantic and provided continuous observations near the eyewall. Measured surface ocean temperature unexpectedly increased during the first half of the storm. Saildrone current shear and upper-ocean structure from the nearest Argo profiles show an initial trapping of wind momentum by a strong halocline in the upper 30 m, followed by deeper mixing and entrainment of warmer subsurface water into the mixed layer. The ocean initial conditions provided to operational forecast models failed to capture the observed upper-ocean structure. The forecast models failed to simulate the warming and developed a surface cold bias of ~0.5°C by the time peak winds were observed, resulting in a 12-17% underestimation of surface enthalpy flux near the eyewall. Results imply that enhanced upper-ocean observations and, critically, improved assimilation into the hurricane forecast systems, could directly benefit hurricane intensity forecasts.</p