A methodology for studying denitrification by recently formed sulfides

Nitrate (N03) contamination due to anthropogenic sources is a serious and widespread health problem. In many groundwater systems, N03-can be reduced to a harmless gas, N2, through the bacterially mediated process of denitrification. During this process, bacteria gain energy by transferring electrons from an electron donor to nitrate, the electron acceptor . It is typically believed that organic carbon is the most important electron donor in the denitrification process; however, increasing amounts of research suggest the importance of inorganic electron donors. The most extensive studies involving the reduction ofN03- by inorganic species have focused on pyrite (FeS2) and Fe(II). Few studies have considered the possibility of denitrification by recently formed sulfide species, such as hydrogen sulfide (H2S), iron monosulfide (FeS), mackinawite (FeS), and greigite (Fe3S4). The objective of this research was to design and begin implementing a methodology for investigating the effects of recently formed sulfides on denitrification. In order to begin investigating the denitrification potential of recently formed sulfides, a 4-foot high, 6-inch diameter Plexiglas column was constructed, with tubing ports on the top and bottom. The column was filled with sediment and groundwater collected from a field site in Fertile, MN. Groundwater from the field site was spiked with organic carbon (glucose) and sulfate. The spiked water was injected into the column, until two pore-volumes of the origina1-column water were flushed out. The spiked water was left in the column for several months, during which the concentrations of several groundwater species were monitored, including: total organic carbon (TOC), total inorganic carbon (TIC), dissolved oxygen (DO), reduced iron (Fe2+), reduced manganese (Mn2l, nitrate (N03-), sulfate (So/-), and pH. The results of the laboratory study revealed that water in the column was reducing according to the thermodynamic model of reduction sequences. The dissolved oxygen concentrations decreased from 8.4 mg/L to 0.8 mg/L. Once concentrations of oxygen became limiting, dissolved manganese and then dissolved iron concentrations increased as the manganese and iron minerals in the sediment were reduced. Dissolved manganese concentrations rose from 2.07 mg/L to 4.40 mg/L, and dissolved iron concentrations increased from\u3c 0.03 mg/L to 2.56 mg/L. Concentrations of total inorganic carbon increased concurrently with the oxidation of organic carbon and the reduction of oxygen, manganese, and iron. The next step in the sequence, sulfate reduction, was not observed during the course of this study. Once enough sulfate is reduced to form sufficient reserves of sulfides, the next step of the methodology is to add nitrate to the column. The expectation is that the sulfides will reduce the nitrate and be oxidized to sulfate

Media Analysis of Coverage of Environmental Issues in the Midst of a Pandemic

This research aimed to answer the question “has the coronavirus impacted the print media’s coverage of important environmental issues?” The research analyzed 2 different print newspapers - The New York Times and the Wall Street Journal - to determine if there was a change in coverage of environmental news as the coronavirus spread in the US. Data for stories published in the first four days of every month from March through September was compiled for 2019 and 2020. Our findings showed a 78.85% decrease in coverage of environmental issues between 2019 and 2020 when stories related to the coronavirus pandemic flooded the news and accounted for 31.9% of all stories published by the two papers. Our findings indicated a clear decrease in the coverage of environmental issues in the print media, brought on by the coronavirus pandemic. This research is an essential first step at quantifying the impacts that major global events have on the news cycle and media coverage of environmental events. It goes to show how the framing of some issues allows readers to take other issues, such as climate change, lightly and view them as not time-sensitive. Media coverage plays an important role in educating and determining the opinions of the public. A lack of coverage of environmental news could be detrimental to public opinion and the policy agenda. It’s important that environmental news coverage is not interrupted to continue supporting the narrative that climate change is an urgent threat to our planet and societies

MERCURY RELEASE FROM DISTURBED ANOXIC SOILS

The primary objectives of experiments conducted at the Energy & Environmental Research Center (EERC) were to provide information on the secondary release of mercury from contaminated anoxic sediments to an aqueous environment after disturbance/change of in situ physical conditions and to evaluate its migration and partitioning under controlled conditions, including implications of these processes for treatment of contaminated soils. Experimental work included (1) characterization of the mercury-contaminated sediment; (2) field bench-scale dredging simulation; (3) laboratory column study to evaluate a longer-term response to sediment disturbance; (4) mercury volatilization from sediment during controlled drying; (5) resaturation experiments to evaluate the potential for secondary release of residual mercury after disturbance, transport, drying, and resaturation, which simulate a typical scenario during soil excavation and transport to waste disposal facilities; and (6) mercury speciation and potential for methylation during column incubation experiments

SRBench: A streaming RDF/SPARQL benchmark

We introduce SRBench, a general-purpose benchmark primarily designed for streaming RDF/SPARQL engines, completely based on real-world data sets from the Linked Open Data cloud. With the increasing problem of too much streaming data but not enough tools to gain knowledge from them, researchers have set out for solutions in which Semantic Web technologies are adapted and extended for publishing, sharing, analysing and understanding streaming data. To help researchers and users comparing streaming RDF/SPARQL (strRS) engines in a standardised application scenario, we have designed SRBench, with which one can assess the abilities of a strRS engine to cope with a broad range of use cases typically encountered in real-world scenarios. The data sets used in the benchmark have been carefully chosen, such that they represent a realistic and relevant usage of streaming data. The benchmark defines a concise, yet omprehensive set of queries that cover the major aspects of strRS processing. Finally, our work is complemented with a functional evaluation on three representative strRS engines: SPARQLStream, C-SPARQL and CQELS. The presented results are meant to give a first baseline and illustrate the state-of-the-art

Superquadric-Based Object Recognition

This paper proposes a technique for object recognition using superquadric built models. Superquadrics, which are three dimensional models suitable for part-level representation of objects, are reconstructed from range images using the recover-and-select paradigm. Using an interpretation three, the presence of an object in the scene from the model database can be hypothesized. These hypotheses are verified by projecting and re-fitting the object model to the range image which at the same time enables a better localization of the object in the scene

Medical Data Architecture Capabilities and Design

Mission constraints will challenge the delivery of medical care on a long-term, deep space explorationmission. This type of mission will be restricted in the availability of medical knowledge, skills, procedures and resourcesto prevent, diagnose, and treat in-flight medical events. Challenges to providing medical care are anticipated, includingresource and resupply constraints, delayed communications and no ability for medical evacuation. The Medical DataArchitecture (MDA) project will enable medical care capability in this constrained environment.The first version of thesystem, called Test Bed 1, includes capabilities for automated data collection, data storage and data retrieval to provideinformation to the Crew Medical Officer (CMO). Test Bed 1 seeks to establish a data architecture foundation and developa scalable data management system through modular design and standardized interfaces. In addition, it will demonstrateto stakeholders the potential for an improved, automated, flow of data to and from the medical system over the currentmethods employed on the International Space Station (ISS). It integrates a set of external devices, software andprocesses, and a Subjective, Objective, Assessment, and Plan (SOAP) note commonly used by clinicians. Medical datalike electrocardiogram plots, heart rate, skin temperature, respiration rate, medications taken, and more are collectedfrom devices and stored in the Electronic Medical Records (EMR) system, and reported to crew and clinician. Devicesintegrated include the Astroskin biosensor vest and IMED CARDIAX electrocardiogram (ECG) device with INEED MDECG Glove, and the NASA-developed Medical Dose Tracker application.The system is designed to be operated as astandalone system, and can be deployed in a variety of environments, from a laptop to a data center. The system isprimarily composed of open-source software tools, and is designed to be modular, so new capabilities can be added. Thesoftware components and integration methods will be discussed

Medical Data Architecture Project Status

The Medical Data Architecture (MDA) project supports the Exploration Medical Capability (ExMC) risk to minimize or reduce the risk of adverse health outcomes and decrements in performance due to in-flight medical capabilities on human exploration missions. To mitigate this risk, the ExMC MDA project addresses the technical limitations identified in ExMC Gap Med 07: We do not have the capability to comprehensively process medically-relevant information to support medical operations during exploration missions. This gap identifies that the current International Space Station (ISS) medical data management includes a combination of data collection and distribution methods that are minimally integrated with on-board medical devices and systems. Furthermore, there are variety of data sources and methods of data collection. For an exploration mission, the seamless management of such data will enable an increasingly autonomous crew than the current ISS paradigm. The MDA will develop capabilities that support automated data collection, and the necessary functionality and challenges in executing a self-contained medical system that approaches crew health care delivery without assistance from ground support.To attain this goal, the first year of the MDA project focused on reducing technical risk, developing documentation and instituting iterative development processes that established the basis for the first version of MDA software (or Test Bed 1). Test Bed 1 is based on a nominal operations scenario authored by the ExMC Element Scientist. This narrative was decomposed into a Concept of Operations that formed the basis for Test Bed 1 requirements. These requirements were successfully vetted through the MDA Test Bed 1 System Requirements Review, which permitted the MDA project to begin software code development and component integration. This paper highlights the MDA objectives, development processes, and accomplishments, and identifies the fiscal year 2017 milestones and deliverables in the upcoming year

Food Anticipatory Activity Behavior of Mice across a Wide Range of Circadian and Non-Circadian Intervals

When rodents are fed in a limited amount during the daytime, they rapidly redistribute some of their nocturnal activity to the time preceding the delivery of food. In rats, anticipation of a daily meal has been interpreted as a circadian rhythm controlled by a food-entrained oscillator (FEO) with circadian limits to entrainment. Lesion experiments place this FEO outside of the light-entrainable circadian pacemaker in the suprachiasmatic nucleus. Mice also anticipate a fixed daily meal, but circadian limits to entrainment and anticipation of more than 2 daily meals, have not been assessed. We used a video-based behavior recognition system to quantify food anticipatory activity in mice receiving 2, 3, or 6 daily meals at intervals of 12, 8, or 4-hours (h). Individual mice were able to anticipate as many as 4 of 6 daily meals, and anticipation persisted during meal omission tests. On the 6 meal schedule, pre-prandial activity and body temperature were poorly correlated, suggesting independent regulation. Mice showed a limited ability to anticipate an 18 h feeding schedule. Finally, mice showed concurrent circadian and sub-hourly anticipation when provided with 6 small meals, at 30 minute intervals, at a fixed time of day. These results indicate that mice can anticipate feeding opportunities at a fixed time of day across a wide range of intervals not previously associated with anticipatory behavior in studies of rats. The methods described here can be exploited to determine the extent to which timing of different intervals in mice relies on common or distinct neural and molecular mechanisms