Lunar Cold Trap Contamination by Landing Vehicles
NASA Technical Reports Server (NTRS)
Shipley, Scott T.; Metzger, Philip T.; Lane, John E.
2014-01-01
Tools have been developed to model and simulate the effects of lunar landing vehicles on the lunar environment (Metzger, 2011), mostly addressing the effects of regolith erosion by rocket plumes and the fate of the ejected lunar soil particles (Metzger, 2010). These tools are being applied at KSC to predict ejecta from the upcoming Google Lunar X-Prize Landers and how they may damage the historic Apollo landing sites. The emerging interest in lunar mining poses a threat of contamination to pristine craters at the lunar poles, which act as "cold traps" for water and may harbor other valuable minerals Crider and Vondrak (2002). The KSC Granular Mechanics and Regolith Operations Lab tools have been expanded to address the probability for contamination of these pristine "cold trap" craters.
Tropical Aquatic Archaea Show Environment-Specific Community Composition
Silveira, Cynthia B.; Cardoso, Alexander M.; Coutinho, Felipe H.; Lima, Joyce L.; Pinto, Leonardo H.; Albano, Rodolpho M.; Clementino, Maysa M.; Martins, Orlando B.; Vieira, Ricardo P.
2013-01-01
The Archaea domain is ubiquitously distributed and extremely diverse, however, environmental factors that shape archaeal community structure are not well known. Aquatic environments, including the water column and sediments harbor many new uncultured archaeal species from which metabolic and ecological roles remain elusive. Some environments are especially neglected in terms of archaeal diversity, as is the case of pristine tropical areas. Here we investigate the archaeal composition in marine and freshwater systems from Ilha Grande, a South Atlantic tropical environment. All sampled habitats showed high archaeal diversity. No OTUs were shared between freshwater, marine and mangrove sediment samples, yet these environments are interconnected and geographically close, indicating environment-specific community structuring. Group II Euryarchaeota was the main clade in marine samples, while the new putative phylum Thaumarchaeota and LDS/RCV Euryarchaeota dominated freshwaters. Group III Euryarchaeota , a rare clade, was also retrieved in reasonable abundance in marine samples. The archaeal community from mangrove sediments was composed mainly by members of mesophilic Crenarchaeota and by a distinct clade forming a sister-group to Crenarchaeota and Thaumarchaeota. Our results show strong environment-specific community structuring in tropical aquatic Archaea, as previously seen for Bacteria. PMID:24086729
USDA-ARS?s Scientific Manuscript database
Although mustelids may play a significant role in the transmission of Trichinella spp., their protected status has limited opportunities to understand their exposure to parasites cycling either among domesticated or wildlife host species. Of the species of Trichinella in Europe, only T. britovi has ...
Eklund, Britta; Hansson, Tomas; Bengtsson, Henrik; Eriksson Wiklund, Ann-Kristin
2016-04-01
This investigation set out to analyze the toxicity of surface sediments in a number of natural harbors and small boat harbors on the west coast of Sweden. This was done with the growth inhibition method with Ceramium tenuicorne. Also, concentrations of copper (Cu), lead (Pb), zinc (Zn), irgarol, organotin compounds, and polycyclic aromatic hydrocarbons (PAHs) in the sediments were analyzed. The small boat harbors were heavily polluted by Cu, Zn, butyltins, and PAHs, and to a lesser extent by Pb. The Cu, Pb, Zn, and butyltins probably originated from their past and/or present use in antifouling paints, whereas the PAHs probably had multiple sources, including boat motor exhausts. The measured toxicity of the sediment was generally related to their Cu, Zn, and butyltin content, although other toxic substances than those analyzed here probably contributed to the toxicity in some of the harbors. The natural harbor sediments contained less pollutants and were less toxic than the small boat harbor sediments. Nevertheless, our data indicate that the boating pressure today may be high enough to produce toxic effects even in natural harbors in pristine areas. The strongest relationship between toxicity and the major pollutants was obtained when the sediment toxicity was expressed as gram wet weight per liter compared with gram dry weight per liter and gram total organic carbon per liter. Hence, for pollutants that can be elutriated with natural sea water, sediment toxicity expressed as gram wet weight per liter appears preferable.
Herrmann, Martina; Rusznyák, Anna; Akob, Denise M.; Schulze, Isabel; Opitz, Sebastian; Totsche, Kai Uwe
2015-01-01
The traditional view of the dependency of subsurface environments on surface-derived allochthonous carbon inputs is challenged by increasing evidence for the role of lithoautotrophy in aquifer carbon flow. We linked information on autotrophy (Calvin-Benson-Bassham cycle) with that from total microbial community analysis in groundwater at two superimposed—upper and lower—limestone groundwater reservoirs (aquifers). Quantitative PCR revealed that up to 17% of the microbial population had the genetic potential to fix CO2 via the Calvin cycle, with abundances of cbbM and cbbL genes, encoding RubisCO (ribulose-1,5-bisphosphate carboxylase/oxygenase) forms I and II, ranging from 1.14 × 103 to 6 × 106 genes liter−1 over a 2-year period. The structure of the active microbial communities based on 16S rRNA transcripts differed between the two aquifers, with a larger fraction of heterotrophic, facultative anaerobic, soil-related groups in the oxygen-deficient upper aquifer. Most identified CO2-assimilating phylogenetic groups appeared to be involved in the oxidation of sulfur or nitrogen compounds and harbored both RubisCO forms I and II, allowing efficient CO2 fixation in environments with strong oxygen and CO2 fluctuations. The genera Sulfuricella and Nitrosomonas were represented by read fractions of up to 78 and 33%, respectively, within the cbbM and cbbL transcript pool and accounted for 5.6 and 3.8% of 16S rRNA sequence reads, respectively, in the lower aquifer. Our results indicate that a large fraction of bacteria in pristine limestone aquifers has the genetic potential for autotrophic CO2 fixation, with energy most likely provided by the oxidation of reduced sulfur and nitrogen compounds. PMID:25616797
Ali, Nida; Sorkhoh, Naser; Salamah, Samar; Eliyas, Mohamed; Radwan, Samir
2012-01-01
The leaves of two legumes, peas and beans, harbored on their surfaces up to 9×10⁷ cells g⁻¹ of oil-utilizing bacteria. Less numbers, up to 5×10⁵ cells g⁻¹ inhabited leaves of two nonlegume crops, namely tomato and sunflower. Older leaves accommodated more of such bacteria than younger ones. Plants raised in oily environments were colonized by much more oil-utilizing bacteria than those raised in pristine (oil-free) environments. Similar numbers were counted on the same media in which nitrogen salt was deleted, indicating that most phyllospheric bacteria were probably diazotrophic. Most dominant were Microbacterium spp. followed by Rhodococcus spp., Citrobacter freundii, in addition to several other minor species. The pure bacterial isolates could utilize leaf tissue hydrocarbons, and consume considerable proportions of crude oil, phenanthrene (an aromatic hydrocarbon) and n-octadecane (an alkane) in batch cultures. Bacterial consortia on fresh (but not on previously autoclaved) leaves of peas and beans could also consume substantial proportions of the surrounding volatile oil hydrocarbons in closed microcosms. It was concluded that phytoremediation through phyllosphere technology could be useful in remediating atmospheric hydrocarbon pollutants. Copyright © 2011 Elsevier Ltd. All rights reserved.
Herrmann, Martina; Rusznyák, Anna; Akob, Denise M.; Schulze, Isabel; Opitz, Sebastian; Totsche, Kai Uwe; Küsel, Kirsten
2015-01-01
The traditional view of the dependency of subsurface environments on surface-derived allochthonous carbon inputs is challenged by increasing evidence for the role of lithoautotrophy in aquifer carbon flow. We linked information on autotrophy (Calvin-Benson-Bassham cycle) with that from total microbial community analysis in groundwater at two superimposed—upper and lower—limestone groundwater reservoirs (aquifers). Quantitative PCR revealed that up to 17% of the microbial population had the genetic potential to fix CO2 via the Calvin cycle, with abundances of cbbM and cbbL genes, encoding RubisCO (ribulose-1,5-bisphosphate carboxylase/oxygenase) forms I and II, ranging from 1.14 × 103 to 6 × 106 genes liter−1 over a 2-year period. The structure of the active microbial communities based on 16S rRNA transcripts differed between the two aquifers, with a larger fraction of heterotrophic, facultative anaerobic, soil-related groups in the oxygen-deficient upper aquifer. Most identified CO2-assimilating phylogenetic groups appeared to be involved in the oxidation of sulfur or nitrogen compounds and harbored both RubisCO forms I and II, allowing efficient CO2 fixation in environments with strong oxygen and CO2 fluctuations. The genera Sulfuricellaand Nitrosomonas were represented by read fractions of up to 78 and 33%, respectively, within the cbbM and cbbL transcript pool and accounted for 5.6 and 3.8% of 16S rRNA sequence reads, respectively, in the lower aquifer. Our results indicate that a large fraction of bacteria in pristine limestone aquifers has the genetic potential for autotrophic CO2 fixation, with energy most likely provided by the oxidation of reduced sulfur and nitrogen compounds.
Anthropogenic platinum and palladium in the sediments of Boston Harbor
Tuit, C.B.; Ravizza, G.E.; Bothner, Michael H.
2000-01-01
Anthropogenic activity has increased recent sediment concentrations of Pt and Pd in Boston Harbor by approximately 5 times background concentrations. Surface sediments and downcore profiles were investigated to evaluate Pt and Pd accumulation and behavior in urban coastal sediments. There is no clear correlation between temporal changes in Pt and Pd consumption and sediment concentration. However, Pt/Pb and Pd/Pb ratios suggest that Pt and Pd flux into the Harbor may not be decreasing with cessation of sludge input as rapidly as other metals. This is supported by the large discrepancy between fluxes associated with sludge and effluent release and those calculated from surface sediment concentrations. This evidence supports catalytic converters as a major source of Pd and Pt to Boston Harbor but cannot preclude other sources. Pd does not exhibit signs of post-burial remobilization below the mixed layer in the sediment cores, although near-surface variability in Pd concentrations may indicate a labile Pd component. Pt displays an inverse correlation with Mn above the oxic/suboxic transition, similar to behavior seen in pristine sediments where Pt is thought to be chemically mobile. This study does not support the use of Pd and Pt as tracers of recent contaminated sedimentation. However, the possibility of a labile Pt and Pd in these sediments highlights the need for further study of the biological uptake of these metals.
Ubiquitous Presence and Novel Diversity of Anaerobic Alkane Degraders in Cold Marine Sediments.
Gittel, Antje; Donhauser, Johanna; Røy, Hans; Girguis, Peter R; Jørgensen, Bo B; Kjeldsen, Kasper U
2015-01-01
Alkanes are major constituents of crude oil and are released to the marine environment by natural seepage and from anthropogenic sources. Due to their chemical inertness, their removal from anoxic marine sediments is primarily controlled by the activity of anaerobic alkane-degrading microorganisms. To facilitate comprehensive cultivation-independent surveys of the diversity and distribution of anaerobic alkane degraders, we designed novel PCR primers that cover all known diversity of the 1-methylalkyl succinate synthase gene (masD/assA), which catalyzes the initial activation of alkanes. We studied masD/assA gene diversity in pristine and seepage-impacted Danish coastal sediments, as well as in sediments and alkane-degrading enrichment cultures from the Middle Valley (MV) hydrothermal vent system in the Pacific Northwest. MasD/assA genes were ubiquitously present, and the primers captured the diversity of both known and previously undiscovered masD/assA gene diversity. Seepage sediments were dominated by a single masD/assA gene cluster, which is presumably indicative of a substrate-adapted community, while pristine sediments harbored a diverse range of masD/assA phylotypes including those present in seepage sediments. This rare biosphere of anaerobic alkane degraders will likely increase in abundance in the event of seepage or accidental oil spillage. Nanomolar concentrations of short-chain alkanes (SCA) were detected in pristine and seepage sediments. Interestingly, anaerobic alkane degraders closely related to strain BuS5, the only SCA degrader in pure culture, were found in mesophilic MV enrichments, but not in cold sediments from Danish waters. We propose that the new masD/assA gene lineages in these sediments represent novel phylotypes that are either fueled by naturally occurring low levels of SCA or that metabolize medium- to long-chain alkanes. Our study highlights that masD/assA genes are a relevant diagnostic marker to identify seepage and microseepage, e.g., during prospecting for oil and gas, and may act as an indicator of anthropogenic oil spills in marine sediments.
Lowell, Jennifer L; Gordon, Nathan; Engstrom, Dale; Stanford, Jack A; Holben, William E; Gannon, James E
2009-10-01
The Nyack floodplain is located on the Middle Fork of the Flathead River, an unregulated, pristine, fifth-order stream in Montana, USA, bordering Glacier National Park. The hyporheic zone is a nutritionally heterogeneous floodplain component harboring a diverse array of microbial assemblages essential in fluvial biogeochemical cycling, riverine ecosystem productivity, and trophic interactions. Despite these functions, microbial community structure in pristine hyporheic systems is not well characterized. The current study was designed to assess whether physical habitat heterogeneity within the hyporheic zone of the Nyack floodplain was sufficient to drive bacterial beta diversity between three different hyporheic flow path locations. Habitat heterogeneity was assessed by measuring soluble reactive phosphorous, nitrate, dissolved organic carbon, dissolved oxygen, and soluble total nitrogen levels seasonally at surface water infiltration, advection, and exfiltration zones. Significant spatial differences were detected in dissolved oxygen and nitrate levels, and seasonal differences were detected in dissolved oxygen, nitrate, and dissolved organic carbon levels. Denaturing gradient gel electrophoresis (DGGE) and cell counts indicated that bacterial diversity increased with abundance, and DGGE fingerprints covaried with nitrate levels where water infiltrated the hyporheic zone. The ribosomal gene phylogeny revealed that hyporheic habitat heterogeneity was sufficient to drive beta diversity between bacterial assemblages. Phylogenetic (P) tests detected sequence disparity between the flow path locations. Small distinct lineages of Firmicutes, Actinomycetes, Planctomycetes, and Acidobacteria defined the infiltration zone and alpha- and beta-proteobacterial lineages delineated the exfiltration and advection zone communities. These data suggest that spatial habitat heterogeneity drives hyporheic microbial community development and that attempts to understand functional differences between bacteria inhabiting nutritionally heterogeneous hyporheic environments might begin by focusing on the biology of these taxa.
NASA Astrophysics Data System (ADS)
Parks, Ashley Nicole
The fate, bioavailability, bioaccumulation and toxicity of single-walled carbon nanotubes (SWNT) have not been extensively studied to date. Pristine SWNT are highly hydrophobic and have been shown to strongly associate with natural particulate matter in aquatic environments. In light of this, I have focused my research to examine the influence of sediment and food exposure routes on bioavailability, bioaccumulation, and toxicity of structurally diverse SWNT in several ecologically-important marine invertebrate species. No significant mortality was observed in any organism at concentrations up to 1000 mg/kg. Evidence of biouptake after ingestion was observed for pristine semiconducting SWNT using NIRF spectroscopy and for oxidized 14C-SWNT using liquid scintillation counting. After a 24 hour depuration period, the pristine semiconducting SWNT were eliminated from organisms to below the method detection limit (5 microg/mL), and the 14C-SWNT body burden was decreased by an order of magnitude to a bioaccumulation factor (BAF) of <0.01. Neither pristine SWNT nor oxidized 14C-SWNT caused environmentally relevant toxicity or bioaccumulation in benthic invertebrates. Overall, the SWNT were not bioavailable and appear to associate with the sediment. In addition to investigating the toxicity and bioaccumulation of SWNT as an independent toxicant, it is important to consider how they will interact with other contaminants in the environment (i.e., increase or decrease toxicity and bioaccumulation of co-contaminants, alter the environmental transport of co-contaminants, induce degradation of co-contaminants, etc.). I wanted to investigate the effects of SWNT on a complex mixture of contaminants already present in a natural system. New Bedford Harbor (NBH) sediment, which is contaminated with polychlorinated biphenyls (PCBs), was amended with pristine SWNT to determine if the presence of SWNT would mitigate the toxicity and bioaccumulation of the PCBs in deposit-feeding invertebrates. A dilution series of the NBH sediment was created using uncontaminated Long Island Sound (LIS) sediment to test 25% NBH sediment, 50% NBH sediment, 75% NBH sediment, and 100% NBH sediment. The results of this work showed increased organism survival and decreased bioaccumulation of PCBs in treatments amended with SWNT, with the greatest reduction observed in the 25% NBH sediment treatment group amended with 10 mg SWNT/g dry sediment. Polyethylene (PE) passive samplers indicated a reduction of interstitial water (ITW) PCB concentration of greater than 90% in the 25% NBH sediment + 10 mg SWNT/g dry sediment amendment. The ITW concentration was reduced because PCBs were not desorbing from the SWNT. Lower bioavailability leads to reduced potential for toxic effects, supporting the observation of increased survival and decreased bioaccumulation. Once in the sediment, not only are SWNT not bioavailable, they act as a highly sorptive phase, such as black carbon (BC), into which hydrophobic organic contaminants (HOCs), such as PCBS and polycyclic aromatic hydrocarbons (PAHs), can partition, thereby reducing the toxicity and bioavailability of co-occurring HOCs. To more fully understand the impact of SWNT in this environment, their biodegradability also needs to be investigated. Biodegradation of SWNT could lead to release and/or transformation of sorbed HOCs as well as a change in the inherent transport, toxicity, and bioaccumulation of SWNT in the estuarine environment. Because the persistence of SWNT will be a primary determinant of the fate of these materials in the environment, I conducted experiments to determine if the fungus Trametes versicolor, the natural bacterial communities present in NBH sediment, and municipal wastewater treatment plant sludge could degrade or mineralize oxidized 14C-SWNT. Over a six month time period, no significant degradation or mineralization was observed. In all treatments, approximately 99% of the 14C-SWNT remained associated with the solid phase, with only approximately 0.8% of added 14C present as dissolved species and only 0.1% present as 14CO2. These small pools of non-SWNT 14C were likely due to trace impurities, as no differences in production were observed between treatments and abiotic (killed) controls. (Abstract shortened by UMI.)
Kardatzke, J T; Neidhardt, K; Dzuban, D P; Sanchez, J L; Azad, A F
1992-07-01
Human intrusion into pristine habitats increases the likelihood of acquiring infectious agents from potentially infective ticks. As part of a larger human serological investigation into tick-borne illnesses, 3,000 ixodid ticks were collected during May, August, and November 1990 at Fort Chaffee, Arkansas. Ticks were examined to determine whether they harbor rickettsiae, ehrlichiae, and Borrelia burgdorferi, and to assess relationship to human exposure to tick-borne infections at Fort Chaffee, Ark. The overall tick infection rates with SFG rickettsiae, B. burgdorferi, and ehrlichiae were 4.8, 0.1, and 0.3%, respectively.
Ahlstrom, C A; Manuel, C S; Den Bakker, H C; Wiedmann, M; Nightingale, K K
2018-02-01
Molecular subtyping is commonly used in foodborne disease surveillance and microbial source tracking. There is a knowledge gap regarding the molecular ecology of foodborne pathogens in non-food-associated environments. The objective of this study was to isolate and subtype foodborne pathogens from pristine natural environments with minimal anthropogenic inputs. Five locations (wilderness areas) in Northern Colorado were sampled during the spring, summer and fall over a 2-year period. Soil, water, sediment, surface soil and wildlife faecal samples were microbiologically analysed to detect Listeria, Salmonella and Shiga toxin-producing Escherichia coli (STEC), and resultant isolates were subtyped. Three samples tested positive for Listeria monocytogenes and 19 samples contained other Listeria spp. Salmonella was isolated from two samples, five samples contained non-O157 STEC, and E. coli O157:H7 was not detected. Two L. monocytogenes isolates from faecal samples collected from the same wilderness area over a year apart shared the same PFGE pattern, while all other isolates had a unique type. Our data indicate that (i) there was a rare presence of human foodborne pathogens in pristine natural environments in Northern Colorado, (ii) there was genetic diversity between organisms isolated within a given wilderness area, and (iii) the Northern Colorado climate and topography may contribute to the low occurrence of these organisms. Relatively little is known about the molecular ecology of foodborne pathogens in pristine natural environments. While foodborne pathogens were rarely detected in wildlife faecal and environmental samples from the wilderness areas in this study, some isolates shared DNA fingerprint types with human clinical isolates from same region during the same time frame, highlighting the need for environmental isolate subtype data. The availability of molecular subtyping data for non-food-associated foodborne pathogen isolates can facilitate epidemiological and microbial source tracking investigations. © 2017 The Society for Applied Microbiology.
78 FR 19158 - Safety Zone; USA Triathlon, Milwaukee Harbor, Milwaukee, WI
Federal Register 2010, 2011, 2012, 2013, 2014
2013-03-29
...-AA00 Safety Zone; USA Triathlon, Milwaukee Harbor, Milwaukee, WI AGENCY: Coast Guard, DHS. ACTION... standards. Therefore, we did not consider the use of voluntary consensus standards. 14. Environment We have... on the human environment. A preliminary environmental analysis checklist supporting this...
APPLICATION OF EMAP METHODS AND INDICATORS TO THE NY/NJ HARBOR
The Comprehensive Conservation and Management Plan (CCMP) for the NY/NJ Harbor requires specific management actions to maintain and restore the Harbor environment. It also specifies that the progress of these management actions on the improvement of sediment quality and biologic...
Yeung-Cheung, Anna K; Melendez, Nadilynn J
2007-02-01
Harbor Island Park of Mamaroneck Harbor is one of the beaches that has been frequently closed to the public due to unsanitary swimming conditions. In 2002, a Gunderboom BPS (Beach Protection System) was reinstalled in Harbor Island Park to lower bacterial levels in swimming areas. The first Gunderboom had been destroyed by an oil spill several years before. The current Gunderboom is an 800 foot curtain made of a treated polypropylene/polyester fabric and the company claims a 99.1% coliform reduction with its use. In this study, water inside and outside the Gunderboom was tested weekly from June to August 2005, and bi-weekly from September to December 2005. Coliscan Membrane Filtration plates were used to recover the relative amounts of Escherichia coli and coliform bacteria from the water. Soft-shelled clams (Mya arenaria) living in both these areas were also tested for their E. coli and coliform bacteria level using 3M Petrifilm plates. Water was also tested from Hudson Park in New Rochelle, a frequently closed beach due to high levels of coliform bacteria, as well as from Read Sanctuary in Rye, a "pristine" beach. Our results showed the amount of E. coli and coliform bacteria recovered from the water inside the Gunderboom were significantly lower (P < 0.05) compared to outside the Gunderboom and Hudson Park. There was 81.9% reduction in E. coli and 51.6% reduction in coliform bacteria inside the Gunderboom as compared to the outside. In addition, significant differences (P < 0.05) were found with lower numbers of E. coli and coliform bacteria recovered from the clams inside the Gunderboom compared to outside the Gunderboom. In conclusion, the Gunderboom system installed in Mamaroneck Harbor resulted in a significant reduction of E. coli and coliform bacteria in the water and clam samples, thus proving its efficiency as a water filter.
Luo, Jiwei; Li, Xue; Ge, Chengjun; Müller, Karin; Yu, Huamei; Huang, Peng; Li, Jiatong; Tsang, Daniel C W; Bolan, Nanthi S; Rinklebe, Jörg; Wang, Hailong
2018-05-08
Pollution of water by single antibiotics has been investigated in depth. However, in reality, a wide range of different contaminants is often mixed in the aquatic environment (contaminant cocktail). Here, single and competitive sorption dynamics of ionizable norfloxacin (NOR), sulfamerazine (SMR) and oxytetracycline (OTC) by both pristine and modified biochars were investigated. Sorption kinetics of the three antibiotics was faster in ternary-solute than single-solute system. Sorption efficiency was enhanced in the competitive system for NOR by the pristine biochar, and for OTC by both the pristine biochar and the modified biochar, while SMR sorption by the pristine biochar and the KOH-modified biochar was inhibited. Sorption was governed by electrostatic interactions, π-π EDA and H-bonds for antibiotics sorption by biochar. SMR and OTC sorption by biochar was influenced by cation bridging and surface complexation, respectively. This research finding will guide the development of treatment procedures for water polluted by multiple antibiotics. Copyright © 2018 Elsevier Ltd. All rights reserved.
Staton, Sarah J.R.; Woodward, Andrea; Castillo, Josemar A.; Swing, Kelly; Hayes, Mark A.
2014-01-01
Large quantities of free protein in the environment and other bioaerosols are ubiquitous throughout terrestrial ground level environments and may be integrative indicators of ecosystem status. Samples of ground level bioaerosols were collected from various ecosystems throughout Ecuador, including pristine humid tropical forest (pristine), highly altered secondary humid tropical forest (highly altered), secondary transitional very humid forest (regrowth transitional), and suburban dry montane deforested (suburban deforested). The results explored the sensitivity of localized aerosol protein concentrations to spatial and temporal variations within ecosystems, and their value for assessing environmental change. Ecosystem specific variations in environmental protein concentrations were observed: pristine 0.32 ± 0.09 μg/m3, highly altered 0.07 ± 0.05 μg/m3, regrowth transitional 0.17 ± 0.06 μg/m3, and suburban deforested 0.09 ± 0.04 μg/m3. Additionally, comparisons of intra-environmental differences in seasonal/daily weather (dry season 0.08 ± 0.03 μg/m3 and wet season 0.10 ± 0.04 μg/m3), environmental fragmentation (buffered 0.19 ± 0.06 μg/m3 and edge 0.15 ± 0.06 μg/m3), and sampling height (ground level 0.32 ± 0.09 μg/m3 and 10 m 0.24 ± 0.04 μg/m3) demonstrated the sensitivity of protein concentrations to environmental conditions. Local protein concentrations in altered environments correlated well with satellite-based spectral indices describing vegetation productivity: normalized difference vegetation index (NDVI) (r2 = 0.801), net primary production (NPP) (r2 = 0.827), leaf area index (LAI) (r2 = 0.410). Moreover, protein concentrations distinguished the pristine site, which was not differentiated in spectral indices, potentially due to spectral saturation typical of highly vegetated environments. Bioaerosol concentrations represent an inexpensive method to increase understanding of environmental changes, especially in densely vegetated ecosystems with high canopies or in areas needing high spatial and temporal resolution. Further research to expand understanding of the applicability of bioaerosol concentrations for environmental monitoring is supported by this pilot study.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 17 2011-07-01 2011-07-01 false South Bend-Elkhart (Indiana)-Benton... PLANNING PURPOSES Designation of Air Quality Control Regions § 81.73 South Bend-Elkhart (Indiana)-Benton Harbor (Michigan) Interstate Air Quality Control Region. The South Bend-Elkhart (Indiana)-Benton Harbor...
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 17 2010-07-01 2010-07-01 false South Bend-Elkhart (Indiana)-Benton... PLANNING PURPOSES Designation of Air Quality Control Regions § 81.73 South Bend-Elkhart (Indiana)-Benton Harbor (Michigan) Interstate Air Quality Control Region. The South Bend-Elkhart (Indiana)-Benton Harbor...
Pristine and γ-irradiated halloysite reinforced epoxy nanocomposites - Insight study
NASA Astrophysics Data System (ADS)
Saif, Muhammad Jawwad; Naveed, Muhammad; Zia, Khalid Mahmood; Asif, Muhammad
2016-10-01
The present study focuses on development of epoxy system reinforced with naturally occurring halloysite nanotubes (HNTs). A comparative study is presented describing the performance of pristine and γ-irradiated HNTs in an epoxy matrix. The γ-irradiation treatment was used for structural modification of natural pristine HNTs under air sealed environment at different absorbed doses and subsequently these irradiated HNTs were incorporated in epoxy resin with various wt% loadings. The consequences of γ-irradiation on HNTs were studied by FTIR and X-ray diffraction analysis (XRD) in terms of changes in functional groups and crystalline characteristics. An improvement is observed in mechanical properties and crack resistance of composites reinforced with γ-irradiated HNTs. The irradiated HNTs imparted an improved flexural and tensile strength/modulus along with better thermal performance.
Schils, Tom
2012-01-01
Volcanically active islands abound in the tropical Pacific and harbor complex coral communities. Whereas lava streams and deep ash deposits are well-known to devastate coral communities through burial and smothering, little is known about the effect of moderate amounts of small particulate ash deposits on reef communities. Volcanic ash contains a diversity of chemical compounds that can induce nutrient enrichments triggering changes in benthic composition. Two independently collected data sets on the marine benthos of the pristine and remote reefs around Pagan Island, Northern Mariana Islands, reveal a sudden critical transition to cyanobacteria-dominated communities in 2009-2010, which coincides with a period of continuous volcanic ash eruptions. Concurrently, localized outbreaks of the coral-killing cyanobacteriosponge Terpios hoshinota displayed a remarkable symbiosis with filamentous cyanobacteria, which supported the rapid overgrowth of massive coral colonies and allowed the sponge to colonize substrate types from which it has not been documented before. The chemical composition of tephra from Pagan indicates that the outbreak of nuisance species on its reefs might represent an early succession stage of iron enrichment (a.k.a. "black reefs") similar to that caused by anthropogenic debris like ship wrecks or natural events like particulate deposition from wildfire smoke plumes or desert dust storms. Once Pagan's volcanic activity ceased in 2011, the cyanobacterial bloom disappeared. Another group of well-known nuisance algae in the tropical Pacific, the pelagophytes, did not reach bloom densities during this period of ash eruptions but new species records for the Northern Mariana Islands were documented. These field observations indicate that the study of population dynamics of pristine coral communities can advance our understanding of the resilience of tropical reef systems to natural and anthropogenic disturbances.
Knebel, H.J.
1993-01-01
Three modern sedimentary environments have been identified and mapped across the glaciated Boston Harbor estuary and adjacent inner shelf of Massachusetts Bay by means of an extensive set of sidescan sonar records and supplemental bathymetric, sedimentary, subbottom and bottom-current data. 1. (1) Environments of erosion and nondeposition appear on the sonographs either as patterns with isolated reflections (caused by outcrops of bedrock, glacial drift, and coastal plain rocks) or as patterns of strong backscatter (caused by coarse-grained lag deposits). Sediments in these environments range from boulder fields to gravelly sands with megaripples. Inside the harbor, areas of erosion or nondeposition are found primarily near mainland and insular shores and within constricted tidal channels, whereas, on the shelf, they are present over extensive areas of hummocky topography near the coast and atop local bathymetric highs offshore. 2. (2) Environments of sediment reworking are characterized on the sonographs by patterns with patches of strong to weak backscatter caused by a combination of erosional and depositional processes. These environments have diverse grain sizes that range from sandy gravels to muds. Within the harbor, the locations of reworked sediments are uncorrelated with the bottom topography, but, on the shelf, they are found on the lower flanks of bathymetric highs, within broad lows and in relatively deep water (30-50 m). 3. (3) Environments of deposition are depicted on the sonographs as uniform patterns of weak backscatter. These areas contain relatively fine-grained muddy sands and muds. Inside the harbor, depositional environments are found over extensive subtidal flats and within sheltered depressions, whereas, on the shelf, they are restricted to broad lows mainly in deep water. The extreme patchiness of modern sedimentary environments within the Boston Harbor-Massachusetts Bay system reflects the interaction between the irregular bottom topography and both geologic and oceanographic processes. The estuarine part of the system is an effective trap for fine-grained detritus because of its protected nature, low wave climate, and large supply of sediments. The open shelf, however, is largely mantled by winnowed and sorted sediments as a result of erosion during past sea-level fluctuations, sediment resuspension and transport by modern waves and currents, and a spatially variable supply of fine-grained sediments.
Effects of forest management practices and environment on occurrence of Armillaria species
Mee-Sook Kim; Ned B. Klopfenstein; Geral I. McDonald
2010-01-01
Influences of environment (indicated by plant associations) and forest management practices on the distribution of Armillaria spp. and genets (vegetative clones) were investigated. A total of 142 isolates of Armillaria was collected from various host trees on pristine and managed sites (thinned and/or fertilized) growing in relatively wet and dry environments in...
Al-Bader, Dhia; Kansour, Mayada K; Rayan, Rehab; Radwan, Samir S
2013-05-01
Biofilms harboring simultaneously anoxygenic and oxygenic phototrophic bacteria, diazotrophic bacteria, and hydrocarbon-utilizing bacteria were established on glass slides suspended in pristine and oily seawater. Via denaturing gradient gel electrophoresis analysis on PCR-amplified rRNA gene sequence fragments from the extracted DNA from biofilms, followed by band amplification, biofilm composition was determined. The biofilms contained anoxygenic phototrophs belonging to alphaproteobacteria; pico- and filamentous cyanobacteria (oxygenic phototrophs); two species of the diazotroph Azospirillum; and two hydrocarbon-utilizing gammaproteobacterial genera, Cycloclasticus and Oleibacter. The coexistence of all these microbial taxa with different physiologies in the biofilm makes the whole community nutritionally self-sufficient and adequately aerated, a condition quite suitable for the microbial biodegradation of aquatic pollutant hydrocarbons.
Natural attenuation is enhanced in previously contaminated and coniferous forest soils.
Kauppi, Sari; Romantschuk, Martin; Strömmer, Rauni; Sinkkonen, Aki
2012-01-01
Prevalence of organic pollutants or their natural analogs in soil is often assumed to lead to adaptation in the bacterial community, which results in enhanced bioremediation if the soil is later contaminated. In this study, the effects of soil type and contamination history on diesel oil degradation and bacterial adaptation were studied. Mesocosms of mineral and organic forest soil (humus) were artificially treated with diesel oil, and oil hydrocarbon concentrations (GC-FID), bacterial community composition (denaturing gradient gel electrophoresis, DGGE), and oil hydrocarbon degraders (DGGE + sequencing of 16S rRNA genes) were monitored for 20 weeks at 16°C. Degradation was advanced in previously contaminated soils as compared with pristine soils and in coniferous organic forest soil as compared with mineral soil. Contamination affected bacterial community composition especially in the pristine mineral soil, where diesel addition increased the number of strong bands in the DGGE gel. Sequencing of cloned 16S rRNA gene fragments and DGGE bands showed that potential oil-degrading bacteria were found in mineral and organic soils and in both pristine and previously contaminated mesocosms. Fast oil degradation was not associated with the presence of any particular bacterial strain in soil. We demonstrate at the mesocosm scale that previously contaminated and coniferous organic soils are superior environments for fast oil degradation as compared with pristine and mineral soil environments. These results may be utilized in preventing soil pollution and planning soil remediation.
Farias, Pedro; Espírito Santo, Christophe; Branco, Rita; Francisco, Romeu; Santos, Susana; Hansen, Lars; Sorensen, Soren
2015-01-01
Microorganisms are responsible for multiple antibiotic resistances that have been associated with resistance/tolerance to heavy metals, with consequences to public health. Many genes conferring these resistances are located on mobile genetic elements, easily exchanged among phylogenetically distant bacteria. The objective of the present work was to isolate arsenic-, antimonite-, and antibiotic-resistant strains and to determine the existence of plasmids harboring antibiotic/arsenic/antimonite resistance traits in phenotypically resistant strains, in a nonanthropogenically impacted environment. The hydrothermal Lucky Strike field in the Azores archipelago (North Atlantic, between 11°N and 38°N), at the Mid-Atlantic Ridge, protected under the OSPAR Convention, was sampled as a metal-rich pristine environment. A total of 35 strains from 8 different species were isolated in the presence of arsenate, arsenite, and antimonite. ACR3 and arsB genes were amplified from the sediment's total DNA, and 4 isolates also carried ACR3 genes. Phenotypic multiple resistances were found in all strains, and 7 strains had recoverable plasmids. Purified plasmids were sequenced by Illumina and assembled by EDENA V3, and contig annotation was performed using the “Rapid Annotation using the Subsystems Technology” server. Determinants of resistance to copper, zinc, cadmium, cobalt, and chromium as well as to the antibiotics β-lactams and fluoroquinolones were found in the 3 sequenced plasmids. Genes coding for heavy metal resistance and antibiotic resistance in the same mobile element were found, suggesting the possibility of horizontal gene transfer and distribution of theses resistances in the bacterial population. PMID:25636836
NASA Astrophysics Data System (ADS)
Akondi, R.; Trexler, R.; Sharma, S.; Mouser, P. J.; Pfiffner, S. M.
2016-12-01
The deep subsurface is known to harbor diverse communities of living microbes, and can therefore be expected to also harbor an equally diverse and likely different set of non-viable microbial populations. In this study, diglyceride fatty acids, (DGFA, biomarkers for non-viable microbes) as well as their compound specific isotopes (CSIA) were used to study the yield and variety of DGFAs in deep subsurface mid-Devonian sediments of different lithologies. Pristine sidewall cores were obtained from intervals in the Marcellus, Mahantango, and the Marcellus/Mahantango formation interface. The biomarkers were extracted and DGFAs were methylated to fatty acid methyl esters (FAMEs) and analyzed using GC-MS, while the CSIAs were performed using GC-irMS. Sediments were also analyzed for total organic carbon (TOC), stable carbon isotopic composition of organic carbon (δ13Corg), inorganic carbon (δ13Ccarb), and nitrogen (δ15Norg). TOC concentration was highest in the Marcellus and there was a general trend of increasing TOC from Mahantango to the Marcellus. The δ13Corg and δ13Ccarb increased and decreased respectively from Mahantango to the Marcellus while δ15Norg did not show any trend. The FAME profiles consisted of normal saturated, monounsaturated, polyunsaturated, branched, epoxy, terminally branched, hydroxyl, and dimethyl esters. The total biomass yield and variety of DGFA-FAME profiles were higher in the Mahantango compared to the samples from the Marcellus formation and Marcellus/Mahantango interface, suggesting the presence of more paleo-microbial activity in the less consolidated Mahantango formation. We attribute this to the smaller pore throat sizes within the Marcellus formation compared to the Mahantango formation. Since organic matter in the sediments is also one of the key sources of energy for microbial metabolism, bulk 13C and CSIA of the lipids will be used to understand the source(s) and pathways of the carbon cycling within the microbial communities.
Across the City and across Grades: Investigating Energy Flow in the Boston Harbor Ecosystem
ERIC Educational Resources Information Center
Hashimoto-Martell, Erin; Clinchot, Michael; Daniels, Haven; Bennie, Fiona
2012-01-01
In the project described in this article, urban students from across grade levels, schools, and abilities were brought together by four science teachers to better understand an ecosystem of their local environment, the Boston Harbor. This project comprises two main field experiences to the Boston Harbor: the first one to a nearby beach, and the…
Modern sedimentary environments in Boston Harbor, Massachusetts
Knebel, H.J.; Rendigs, R. R.; Bothner, Michael H.
1991-01-01
Analyses of sidescan-sonar records supplemented by available bathymetric, sedimentary, subbottom, and bottom-current data reveal the distributions of the following three categories of sedimentary environments within the glaciated, topographically complex Boston Harbor estuary in Massachusetts. 1) Environments of erosion appear on the sonographs either as patterns with isolated strong reflections or as uniform patterns of strong reflectivity. These patterns define outcrops of bedrock or till and coarse lag deposits that are being scoured and winnowed by tidal- and wave-induced currents. Erosional areas are located primarily along mainland and insular shores, within large channels that have strong tidal currents, atop submerged ridges and knolls, and across much of the harbor entrance. 2) Environments of deposition are depicted on the sidescan-sonar records as smooth, featureless surfaces that have low to moderate reflectivity. Depositional environments are found predominantly over shallow subtidal flats and in broad bathymetric lows where tidal currents are weak. Sediments within depositional areas are organic-rich sandy and clayey silts that are accumulating at rates ranging from 0.01 to 0.11 g/cm 2 /yr or 4000 to 46,100 metric tons/yr. The cumulative mass of modern mud in harbor depocenters is 24.3 million metric tons. 3) Environments of sediment reworking constitute areas affected by a combination of erosional and depositional processes. They are characterized on the sonographs by mosaics of light and dark patches produced by relatively subtle and gradational changes in reflectivity. Reworked sediments have diverse grain sizes that overlap and are transitional between those of the other two sedimentary environments, and they are indicative of highly variable bottom currents.
Manheim, F.T.; Butman, B.
1994-01-01
Discharge of sewage sludge and effluent from 43 communities in the greater Boston metropolitan area has helped make the harbor one of the most polluted in the nation. As part of a court-mandated plan to end pollution of the harbor, effluent will no longer be discharged into the harbor, but instead, by 1995 it will be discharged into Massachusetts Bay through a record-long 15.34 km tunnel. By the year 2000 all of the sewage is scheduled to recive full secondary treatment. The public is concerned about long-term effects of the new ocean outfall on the environment, including Cape Cod Bay and Stellwagen Bank, which is an important habitat for whales and a newly designated national marine sanctuary. The bay has been additionally stressed by dumping of low-level radioactive and other hazardous wastes during the 1950s and 1960s. -from Authors
OSIRIS-REx Contamination Control Strategy and Implementation
NASA Technical Reports Server (NTRS)
Dworkin, J. P.; Adelman, L. A.; Ajluni, T.; Andronikov, A. V.; Aponte, J. C.; Bartels, A. E.; Beshore, E.; Bierhaus, E. B.; Brucato, J. R.; Bryan, B. H.;
2017-01-01
OSIRIS-REx will return pristine samples of carbonaceous asteroid Bennu. This manuscript describes how pristine was defined based on expectations of Bennu and on a realistic understanding of what is achievable with a constrained schedule and budget, and how that definition flowed to requirements and implementation. To return a pristine sample, the OSIRIS-REx spacecraft sampling hardware was maintained at Level 100 A/2 and less than 180 nanograms per square centimeter of amino acids and hydrazine on the sampler head through precision cleaning, control of materials, and vigilance. Contamination is further characterized via witness material exposed to the spacecraft assembly and testing environment as well as in space. This characterization provided knowledge of the expected background and will be used in conjunction with archived spacecraft components for comparison with the samples when they are delivered to Earth for analysis. Most of all, the cleanliness of the OSIRIS-REx spacecraft was achieved through communication between scientists, engineers, managers, and technicians.
OSIRIS-REx Contamination Control Strategy and Implementation
NASA Astrophysics Data System (ADS)
Dworkin, J. P.; Adelman, L. A.; Ajluni, T.; Andronikov, A. V.; Aponte, J. C.; Bartels, A. E.; Beshore, E.; Bierhaus, E. B.; Brucato, J. R.; Bryan, B. H.; Burton, A. S.; Callahan, M. P.; Castro-Wallace, S. L.; Clark, B. C.; Clemett, S. J.; Connolly, H. C.; Cutlip, W. E.; Daly, S. M.; Elliott, V. E.; Elsila, J. E.; Enos, H. L.; Everett, D. F.; Franchi, I. A.; Glavin, D. P.; Graham, H. V.; Hendershot, J. E.; Harris, J. W.; Hill, S. L.; Hildebrand, A. R.; Jayne, G. O.; Jenkens, R. W.; Johnson, K. S.; Kirsch, J. S.; Lauretta, D. S.; Lewis, A. S.; Loiacono, J. J.; Lorentson, C. C.; Marshall, J. R.; Martin, M. G.; Matthias, L. L.; McLain, H. L.; Messenger, S. R.; Mink, R. G.; Moore, J. L.; Nakamura-Messenger, K.; Nuth, J. A.; Owens, C. V.; Parish, C. L.; Perkins, B. D.; Pryzby, M. S.; Reigle, C. A.; Righter, K.; Rizk, B.; Russell, J. F.; Sandford, S. A.; Schepis, J. P.; Songer, J.; Sovinski, M. F.; Stahl, S. E.; Thomas-Keprta, K.; Vellinga, J. M.; Walker, M. S.
2018-02-01
OSIRIS-REx will return pristine samples of carbonaceous asteroid Bennu. This article describes how pristine was defined based on expectations of Bennu and on a realistic understanding of what is achievable with a constrained schedule and budget, and how that definition flowed to requirements and implementation. To return a pristine sample, the OSIRIS-REx spacecraft sampling hardware was maintained at level 100 A/2 and <180 ng/cm2 of amino acids and hydrazine on the sampler head through precision cleaning, control of materials, and vigilance. Contamination is further characterized via witness material exposed to the spacecraft assembly and testing environment as well as in space. This characterization provided knowledge of the expected background and will be used in conjunction with archived spacecraft components for comparison with the samples when they are delivered to Earth for analysis. Most of all, the cleanliness of the OSIRIS-REx spacecraft was achieved through communication among scientists, engineers, managers, and technicians.
OSIRIS-REx Contamination Control Strategy and Implementation
NASA Technical Reports Server (NTRS)
Dworkin, J. P.; Adelman, L. A.; Ajluni, T. M.; Andronikov, A. V.; Aponte, J. S.; Bartels, A. E.; Beshore, E.; Bierhaus, E. B.; Brucato, J. R.; Bryan, B. H.;
2017-01-01
OSIRIS-REx will return pristine samples of carbonaceous asteroid Bennu. This article describes how pristine was defined based on expectations of Bennu and on a realistic understanding of what is achievable with a constrained schedule and budget, and how that definition flowed to requirements and implementation. To return a pristine sample, the OSIRIS-REx spacecraft sampling hardware was maintained at level 100 A/2 and less than 180 ng/cm(exp 2) of amino acids and hydrazine on the sampler head through precision cleaning, control of materials, and vigilance. Contamination is further characterized via witness material exposed to the spacecraft assembly and testing environment as well as in space. This characterization provided knowledge of the expected background and will be used in conjunction with archived spacecraft components for comparison with the samples when they are delivered to Earth for analysis. Most of all, the cleanliness of the OSIRIS-REx spacecraft was achieved through communication among scientists, engineers, managers, and technicians.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mayhew, H.L.; Karle, L.M.; Gruendell, B.D.
The US Army Corps of Engineers was authorized to dredge Richmond Harbor to accomodate large, deep-draft vessels. An ecological evaluation of the Harbor sediments was performed describing the physical characteristics, toxic substances, effects on aquatic organisms,and potential for bioaccumulation of chemical contaminants. The objective of this report is to compare the sediment chemistry, acute toxicity, and bioaccumulation results of the Richmond Harbor sediments to each of the reference areas; i.e., the Deep Off-Shelf Reference Area, the Bay Farm Borrow Area, and the Alcatraz Environs Reference Area. This report will enable the US Army Corps of Engineers to determine whether disposalmore » at a reference area is appropriate for all or part of the dredged material from Richmond Harbor. Chemical analyses were performed on 30 sediment samples; 28 of those samples were then combined to form 7 composites. The seven composites plus sediment from two additional stations received both chemical and biological evaluations.« less
Hokama, Y; Wachi, K M; Shiraki, A; Goo, C; Ebesu, J S
2001-02-01
The biological assessments of the flora and fauna in the near-shore ocean environment, specifically Barbers Point Harbor (BPH), demonstrate the usefulness of these biological analyses for evaluation of the changes occurring following man-made excavation for expansion of the harbor. The study included identification and enumeration of macroalgae and dinoflagellates and analyses of herbivores and carnivores in four areas within the perimeter of the harbor and the north and south entrances into the harbor. Numbers of macroalgae varied between 1994 and 1999 surveys, with significant decrease in numbers in stations C, D and E. Stations A and B were similar between 1994 and 1999 with a slight increase in 1999. The significant differences were shown with the appearance of Gambierdiscus toxicus (G toxicus) in 1999 among the algae in stations A and B. Assessment of herbivores and carnivores with the immunological membrane immunobead assay using monoclonal antibody to ciguatoxin and related polyethers demonstrated an increase in fish toxicity among the herbivore from 1994-1999 (22% increase) with a decrease (22%) in non-toxic fish. This was also demonstrated in the carnivores, but to a lesser degree. It is suggested that the biological analyses of the flora and the fauna of the near-shore ocean environment are appropriate to assess the changes that occur from natural and man-made alterations.
Chen, Baowei; Yang, Ying; Liang, Ximei; Yu, Ke; Zhang, Tong; Li, Xiangdong
2013-11-19
Knowledge of the origins and dissemination of antibiotic resistance genes (ARGs) is essential for understanding modern resistomes in the environment. The mechanisms of the dissemination of ARGs can be revealed through comparative studies on the metagenomic profiling of ARGs between relatively pristine and human-impacted environments. The deep ocean bed of the South China Sea (SCS) is considered to be largely devoid of anthropogenic impacts, while the Pearl River Estuary (PRE) in south China has been highly impacted by intensive human activities. Commonly used antibiotics (sulfamethazine, norfloxacin, ofloxacin, tetracycline, and erythromycin) have been detected through chemical analysis in the PRE sediments, but not in the SCS sediments. In the relatively pristine SCS sediments, the most prevalent and abundant ARGs are those related to resistance to macrolides and polypeptides, with efflux pumps as the predominant mechanism. In the contaminated PRE sediments, the typical ARG profiles suggest a prevailing resistance to antibiotics commonly used in human health and animal farming (including sulfonamides, fluoroquinolones, and aminoglycosides), and higher diversity in both genotype and resistance mechanism than those in the SCS. In particular, antibiotic inactivation significantly contributed to the resistance to aminoglycosides, β-lactams, and macrolides observed in the PRE sediments. There was a significant correlation in the levels of abundance of ARGs and those of mobile genetic elements (including integrons and plasmids), which serve as carriers in the dissemination of ARGs in the aquatic environment. The metagenomic results from the current study support the view that ARGs naturally originate in pristine environments, while human activities accelerate the dissemination of ARGs so that microbes would be able to tolerate selective environmental stress in response to anthropogenic impacts.
Ultrafast-electron-diffraction studies of predamaged tungsten excited by femtosecond optical pulses
NASA Astrophysics Data System (ADS)
Mo, M.; Chen, Z.; Li, R.; Wang, Y.; Shen, X.; Dunning, M.; Weathersby, S.; Makasyuk, I.; Coffee, R.; Zhen, Q.; Kim, J.; Reid, A.; Jobe, K.; Hast, C.; Tsui, Y.; Wang, X.; Glenzer, S.
2016-10-01
Tungsten is considered as the main candidate material for use in the divertor of magnetic confinement fusion reactors. However, radiation damage is expected to occur because of its direct exposure to the high flux of hot plasma and energetic neutrons in fusion environment. Hence, understanding the material behaviors of W under these adverse conditions is central to the design of magnetic fusion reactors. To do that, we have recently developed an MeV ultrafast electron diffraction probe to resolve the structural evolution of optically excited tungsten. To simulate the radiation damage effect, the tungsten samples were bombarded with 500 keV Cu ions. The pre-damaged and pristine W's were excited by 130fs, 400nm laser pulses, and the subsequent heated system was probed with 3.2MeV electrons. The pump probe measurement shows that the ion bombardment to the W leads to larger decay in Bragg peak intensities as compared to pristine W, which may be due to a phonon softening effect. The measurement also shows that pre-damaged W transitions into complete liquid phase for conditions where pristine W stays solid. Our new capability is able to test the theories of structural dynamics of W under conditions relevant to fusion reactor environment. The research was funded by DOE Fusion Energy Science under FWP #100182.
Isle Royale National Park transportation study
DOT National Transportation Integrated Search
2015-04-02
Isle Royale National Park is a remote archipelago located in western Lake Superior, fourteen miles from the closest mainland and 60 : miles from the parks headquarters in Houghton, MI. While visitors treasure the parks pristine environment and sol...
Evaluation of Environmental Aging of Polypropylene Irradiated Versus Pristine
NASA Astrophysics Data System (ADS)
Romano, Rebeca S. Grecco; Oliani, Washington Luiz; Parra, Duclerc Fernandes; Lugao, Ademar Benevolo
Polypropylene (PP) is the most common thermoplastic resin of the plastic market due to its very interesting physical, chemical and processing properties at very low market price, however after its use the resin does not degrade in the environment or it degrades at very low rate. This study has the objective of comparing the environmental exposure of PP irradiated with 20 kGy and pristine PP. Dumbbell samples were manufactured by injection molding and exposed to the environment during 90 days; another one set was subjected to gamma irradiation at 20 kGy total dose and exposed at the same conditions too. The samples were characterized by mechanical testing, visual inspection, infrared spectroscopy (IR), scanning electron microscopy (SEM) and differential scanning calorimetry (DSC). The irradiated samples, after environmental aging, showed oxidation and presence of cracks in samples of the PP 20 kGy.
ERIC Educational Resources Information Center
Richmond, Laurie; Di Piero, Daniela; Espinoza, Flowers; Simeonoff, Teacon; Faraday, Margaret
2010-01-01
On a small island belonging to the Alutiiq people of Old Harbor, 11 people sat around a campfire. Two community leaders, a nonprofit organizer, an academic scholar, a native filmmaker, and six young people from the Indian reservation of Taos Pueblo in New Mexico gathered after a day of interacting with Old Harbor residents--fishing, hunting and…
The Metallicity of Void Dwarf Galaxies
NASA Astrophysics Data System (ADS)
Kreckel, K.; Croxall, K.; Groves, B.; van de Weygaert, R.; Pogge, R. W.
2015-01-01
The current ΛCDM cosmological model predicts that galaxy evolution proceeds more slowly in lower density environments, suggesting that voids are a prime location to search for relatively pristine galaxies that are representative of the building blocks of early massive galaxies. To test the assumption that void galaxies are more pristine, we compare the evolutionary properties of a sample of dwarf galaxies selected specifically to lie in voids with a sample of similar isolated dwarf galaxies in average density environments. We measure gas-phase oxygen abundances and gas fractions for eight dwarf galaxies (Mr > -16.2), carefully selected to reside within the lowest density environments of seven voids, and apply the same calibrations to existing samples of isolated dwarf galaxies. We find no significant difference between these void dwarf galaxies and the isolated dwarf galaxies, suggesting that dwarf galaxy chemical evolution proceeds independent of the large-scale environment. While this sample is too small to draw strong conclusions, it suggests that external gas accretion is playing a limited role in the chemical evolution of these systems, and that this evolution is instead dominated mainly by the internal secular processes that are linking the simultaneous growth and enrichment of these galaxies.
The New Bedford Harbor Superfund Site Long Term Monitoring Program (1993-2009)
New Bedford Harbor (NBH), located in southeastern Massachusetts, was designated as a marine Superfund site in 1983 due to sediment contamination by polychlorinated biphenyls (PCBs). Based on risks to human health and the environment, the first two phases of the site cleanup invo...
Knebel, H.J.; Circe, R.C.
1995-01-01
Modern seafloor sedimentary environments within the glaciated, topographically complex Boston Harbor and Massachusetts Bay area have been interpreted and mapped from an extensive collection of sidescan sonar records and supplemental marine geologic data. Three categories of environments are present that reflect the dominant long-term processes of erosion or nondeposition, deposition, and sediment reworking. (1) Environments of erosion or nondeposition comprise exposures of bedrock, glacial drift, coarse lag deposits, and possibly coastal plain rocks that contain sediments (where present) ranging from boulder fields to gravelly sands and occur in areas of relatively strong currents. (2) Environments of deposition contain fine-grained sediments ranging from muddy sands to muds that have accumulated in areas of predominantly weak bottom currents. (3) Environments of sediment reworking contain patches with textures ranging from sandy gravels to muds that have been produced by a combination of erosion and deposition in areas with variable bottom currents. The distribution of sedimentary environments across the Boston Harbor-Massachusetts Bay area is extremely patchy. Locally, this patchiness is due either to modifications of bottom-current strength (caused by the irregular topography and differences in water depth) or to small-scale changes in the supply of fine-grained sediments. Regional patchiness, however, reflects differences in geologic and oceanographic conditions among the estuarine, inner shelf, and basinal parts of the sedimentary system. The estuarine part of the system (Boston Harbor) is a depositional trap for fine-grained sediments because it is protected from large waves, has generally weak and variable tidal currents, and receives a large supply of fine grained detritus from natural and anthropogenic sources. The inner shelf, on the other hand, is largely an area of erosion or nondeposition due to sediment removal and redistribution during past sea-level changes, to sediment resuspension and winnowing by modern waves and currents, and to an inadequate supply of fine-grained sediments. The basinal part of the system (Stellwagen Basin) is mainly a tranquil depositional environment in which fine-grained sediments from several potential sources settle through the water column and accumulate under weak bottom currents. This study indicates areas within the Boston Harbor-Massachusetts Bay sedimentary system where fine-grained sediments and associated contaminants are likely to be either moved or deposited. It also provides a guide to the locations and variability of benthic habitats.
Single cell genomic study of Dehalococcoidites in deep sea sediments of Peru Margin 1230
NASA Astrophysics Data System (ADS)
Kaster, A.; Meyer-Blackwell, K.; Spormann, A. M.
2013-12-01
Dehalogenating Chloroflexi, such as Dehalococcoidites Dhc were originally discovered as the key microorganisms mediating reductive dehalogenation of the prevalent groundwater contaminants tetrachloroethene and trichloroethene. Molecular and genomic studies on their key enzymes for energy conservation, reductive dehalogenases rdh, have provided evidence for ubiquitous horizontal gene transfer. A pioneering study by Futagami et al. discovered novel putative rdh phylotypes in sediments from the Pacific, revealing an unknown and surprising abundance of rdh genes in pristine habitats. The frequent detection of Dhc-related 16S rRNA genes from these environments implied the occurrence of dissimilatory dehalorespiration in marine subsurface sediments, however, pristine Dhc could never be linked to this activity. Despite being ubiquitous in those environments, metabolic life style or ecological function of Dhc in the absence of anthropogenic contaminants is still completely unknown. We therefore analyzed a non-contaminated deep sea sediment sample of the Peru Margin 1230 site by a single cell genomic (SGC) approach. We present for the first time data on three single Dhc cells, helping to elucidate their role in the poorly understood oligotrophic marine sub-surface environment.
Federal Register 2010, 2011, 2012, 2013, 2014
2012-05-25
... significant effect on the human environment. This rule involves security during the arrival, commissioning... DEPARTMENT OF HOMELAND SECURITY Coast Guard 33 CFR Part 165 [Docket No. USCG-2012-0333] RIN 1625-AA87 Security Zone; USS MISSISSIPPI Commissioning; Pascagoula Harbor & Pascagoula River; Pascagoula, MS...
78 FR 54392 - Security Zone, Baltimore Harbor, Baltimore's Inner Harbor; Baltimore, MD
Federal Register 2010, 2011, 2012, 2013, 2014
2013-09-04
... restriction of vessel traffic is necessary to protect life, property and the environment, therefore, a 30-day... of the Port the ability to implement comprehensive port security regimes designed to safeguard human life, vessels, and waterfront facilities while still sustaining the flow of commerce. The Captain of...
The New Bedford Harbor Superfund Site Long Term Monitoring Program: Results from 1993 to 2014
Background. New Bedford Harbor (NBH), located in southeastern Massachusetts, was designated as a marine Superfund site in 1983 due to sediment contamination by polychlorinated biphenyls (PCBs). Based on risks to human health and the environment, the first two phases of the site ...
1996-11-01
and has determined a finding of no significant impact (FONSI). The selected Syracuse Inner Harbor dredging plan would allow the New York State Canal...Facility (CDF) UDS 5-19. The proposed plan calls for a 60 foot bottom wide channel, 10 feet deep, 3H (height): 1 (vertical) side slopes, with only the...sediments in an urban environment. The selected Syracuse Inner Harbor dredging plan would allow the New York State Canal Corporation to dredge the
NASA Astrophysics Data System (ADS)
Fey, George T. K.; Kao, H. M.; Muralidharan, P.; Kumar, T. P.; Cho, Y. D.
The surface of LiCoO 2 cathodes was coated with various wt.% of Al 2O 3 derived from methoxyethoxy acetate-alumoxane (MEA-alumoxane) by a mechano-thermal coating procedure, followed by calcination at 723 K in air for 10 h. The structure and morphology of the surface modified LiCoO 2 samples have been characterized with XRD, SEM, EDS, TEM, BET, XPS/ESCA and solid-state 27Al magic angle spinning (MAS) NMR techniques. The Al 2O 3 coating forms a thin layer on the surface of the core material with an average thickness of 20 nm. The corresponding 27Al MAS NMR spectrum basically exhibited the same characteristics as the spectrum for pristine Al 2O 3 derived from MEA-alumoxane, indicating that the local environment of aluminum atoms was not significantly changed at coating levels below 1 wt.%. This provides direct evidence that Al 2O 3 was on the surface of the core materials. The LiCoO 2 coated with 1 wt.% Al 2O 3 sustained continuous cycle stability 13 times longer than pristine LiCoO 2. A comparison of the electrochemical impedance behavior of the pristine and coated materials revealed that the failure of pristine cathode performance is associated with an increase in the particle-particle resistance upon continuous cycling. Coating improved the cathode performance by suppressing the characteristic structural phase transitions (hexagonal to monoclinic to hexagonal) that occur in pristine LiCoO 2 during the charge-discharge processes.
BACTERIAL RESPIRATION OF ARSENIC AND SELENIUM. (R826105)
Oxyanions of arsenic and selenium can be used in microbial anaerobic respiration as terminal electron acceptors. The detection of arsenate and selenate respiring bacteria in numerous pristine and contaminated environments and their rapid appearance in enrichme...
75 FR 5907 - Safety Zone; Dive Platform, Pago Pago Harbor, American Samoa
Federal Register 2010, 2011, 2012, 2013, 2014
2010-02-05
... platform vessel in Pago Pago Harbor, American Samoa, while diving operations are under way in and around the CHEHALIS wreck. The safety zone is necessary to protect other vessels and the general public from... Pago, American Samoa. Today, the CHEHALIS wreck remains a potential pollution threat to the environment...
USDA-ARS?s Scientific Manuscript database
Insect guts harbor diverse microbial assemblages that can be influenced by multiple factors, including gut physiology and interactions by the host with its environment. The Asian longhorned beetle (ALB; Anoplophora glabripennis) is an invasive tree–killing insect, which harbors a diverse consortium ...
Lin, Tian; Hu, Zhaohui; Zhang, Gan; Li, Xiangdong; Xu, Weihai; Tang, Jianhui; Li, Jun
2009-11-01
DDT remains an important type of persistent organic pollutant (POP) in the environment of China. One of the current applications of DDT in China has been through antifouling paint for fishing ships as an active component. It has been estimated that approximately 5000 t of DDT was released into the Chinese coastal environment during the last two decades. Therefore, sediments in coastal fishing harbors of China may be the important sinks of DDT. In this study, DDT and its metabolites in 58 sediment samples from nine typical fishing harbors along the coastal line of China were characterized to assess their accumulation levels, sediment burdens, and potential ecological risks. The concentrations of DDTs ranged from 9 to 7350 ng/g dry weight, which were generally 1-2 orders of magnitude higher than those of the adjacent estuarine/marine sediments. The high concentrations of DDT coupled with the lower concentrations of HCH and TOC clearly indicated a strong local DDT input, i.e., DDT-containing antifouling paint, within the fishing harbors. A significant correlation between the total DDT concentrations and p,p'-DDT concentrations further confirmed the existence of fresh DDT input. The overall burden of DDTs within the upper 10 cm sediment layer in the fishing harbors of the Pearl River Delta, southern China, was estimated to be 1.0-5.7 t, which was several times higher than the DDT accumulation in the surface sediment of the Pearl River estuary. The concentrations of DDTs in the fishing harbor sediments significantly exceeded the sediment quality guidelines on the basis of adverse biological effects. The absence or low concentrations of p,p'-DDD in aquatic organisms and human may imply that either p,p'-DDD may be less bioaccumulated by fish and human, or is biotransformed to other metabolites. A national ban of DDT as an additive to antifouling paint was implemented in 2009 in China; however, the legacy high DDT burden in the coastal fishing harbors needs further monitoring and proper management.
Sundararajan, S; Khadanga, Mukunda Kesari; Kumar, J Prince Prakash Jeba; Raghumaran, S; Vijaya, R; Jena, Basanta Kumar
2017-01-15
In this study, different types of indices were used to assess the ecological risk of trace metal contamination in sediments on the basis of sediment quality guidelines at Veraval Fishery Harbor. Sediment samples were collected from three sectors in pre-, post-, and monsoon seasons in 2006. Trace metal concentrations were higher in the inner sector during post-monsoon, and it showed the highest statistical significance (p<0.01) among the stations. Pollution load index was higher than unity, indicating alternation by effluent discharge from industries. Enrichment factor and geo-accumulation index showed that Cd, Pb, and Zn were enriched in the northern part of the harbor and Pb had accumulated in the harbor sediment. The ecological risk assessment index revealed that Ni, Zn, and Pb were higher than the effect range median values, indicating their potential toxicity to the aquatic environment in the Veraval Harbor. Hence, the harbor is dominated by anthropogenic activities rather than natural process. Copyright © 2016 Elsevier Ltd. All rights reserved.
Impact of ambient environment on the electronic structure of CuPc/Au sample
NASA Astrophysics Data System (ADS)
Sinha, Sumona; Mukherjee, M.
2018-02-01
The performances of organic devices are crucially connected with their stability in the ambient environment. The impact of 24 h. Ambient environment exposure to the electronic structures of about 12 nm thick CuPc thin film on clean Au substrate have been studied employing UV photoemission spectroscopy technique. X-ray photoemission spectroscopy (XPS) was used to find out the origin of the change of the electronic structures in the sample with the exposure. The XPS study suggests that the oxidation occurs at the CuPc thin film. Due to the adsorption of oxygen in the CuPc film from the ambient air, charge carriers are formed within the CuPc film. Moreover, the XPS results imply that the CuPc film is sufficiently thinner for diffusing oxygen molecules through it and gets physically absorbed on Au substrate during the ambient exposure. Consequently, the hole injection barrier height of pristine CuPc film, grown on Au substrate, is reduced by about 0.50 eV and work-function of the pristine CuPc sample is enhanced by around 0.25 eV in the exposure. The findings will help to understand the mechanism that governs the degradation of performance of CuPc based devices in ambient environment.
USDA-ARS?s Scientific Manuscript database
Antarctica is a pristine and extreme environment that represents a unique opportunity for taxonomic, ecological and biotechnological studies of the microorganisms. In the present work, the fungal communities of rhizosphere soil of Deschampsia antarctica, soil, ornithogenic soil, marine and lake sedi...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Simpson, H.J.; Williams, S.C.
We have obtained a large set of cores from the Hudson Estuary covering nearly all of the ambient salinity range. A number of core sections have been analyzed for /sup 137/Cs, /sup 134/Cs, /sup 60/Co and /sup 40/K by direct gamma counting and for /sup 239/,/sup 240/Pu and /sup 238/Pu by alpha-spectrometry. Rapid accumulation, up to 20 cm/year, of sediments containing /sup 239/,/sup 240/Pu, /sup 137/Cs, /sup 134/Cs and /sup 60/Co occurs in New York Harbor. Marginal coves upstream from the harbor also serve as depositional environments. The ratio of sediment /sup 239,240/Pu to /sup 137/Cs is higher than themore » fallout ratio in the seaward end of New York Harbor, despite the presence of a significant component of reactor /sup 137/Cs in the sediments, but lower than the range of ratios observed by others for nearshore environments with low sediment deposition rates. A substantial portion of gamma emitting fission product and activation nuclides released from the Indian Point nuclear facility have accumulated in New York Harbor, more than 60 km downstream from the release area. We have not yet established whether local transuranic releases to the Hudson have occurred.« less
Fonseca, Erica L.; Andrade, Bruno G. N.; Vicente, Ana C. P.
2018-01-01
The worldwide dispersion and sudden emergence of new antibiotic resistance genes (ARGs) determined the need in uncovering which environment participate most as their source and reservoir. ARGs closely related to those currently found in human pathogens occur in the resistome of anthropogenic impacted environments. However, the role of pristine environment as the origin and source of ARGs remains underexplored and controversy, particularly, the marine environments represented by the oceans. Here, due to the ocean nature, we hypothesized that the resistome of this pristine/low-impacted marine environment is represented by distant ARG homologs. To test this hypothesis we performed an in silico analysis on the Global Ocean Sampling (GOS) metagenomic project dataset focusing on the metallo-β-lactamases (MβLs) as the ARG model. MβLs have been a challenge to public health, since they hydrolyze the carbapenems, one of the last therapeutic choice in clinics. Using Hidden Markov Model (HMM) profiles, we were successful in identifying a high diversity of distant MβL homologs, related to the B1, B2, and B3 subclasses. The majority of them were distributed across the Atlantic, Indian, and Pacific Oceans being related to the chromosomally encoded MβL GOB present in Elizabethkingia genus. It was observed only a reduced number of metagenomic sequence homologs related to the acquired MβL enzymes (VIM, SPM-1, and AIM-1) that currently have impact in clinics. Therefore, low antibiotic impacted marine environment, as the ocean, are unlikely the source of ARGs that have been causing enormous threat to the public health. PMID:29675014
Fonseca, Erica L; Andrade, Bruno G N; Vicente, Ana C P
2018-01-01
The worldwide dispersion and sudden emergence of new antibiotic resistance genes (ARGs) determined the need in uncovering which environment participate most as their source and reservoir. ARGs closely related to those currently found in human pathogens occur in the resistome of anthropogenic impacted environments. However, the role of pristine environment as the origin and source of ARGs remains underexplored and controversy, particularly, the marine environments represented by the oceans. Here, due to the ocean nature, we hypothesized that the resistome of this pristine/low-impacted marine environment is represented by distant ARG homologs. To test this hypothesis we performed an in silico analysis on the Global Ocean Sampling (GOS) metagenomic project dataset focusing on the metallo-β-lactamases (MβLs) as the ARG model. MβLs have been a challenge to public health, since they hydrolyze the carbapenems, one of the last therapeutic choice in clinics. Using Hidden Markov Model (HMM) profiles, we were successful in identifying a high diversity of distant MβL homologs, related to the B1, B2, and B3 subclasses. The majority of them were distributed across the Atlantic, Indian, and Pacific Oceans being related to the chromosomally encoded MβL GOB present in Elizabethkingia genus. It was observed only a reduced number of metagenomic sequence homologs related to the acquired MβL enzymes (VIM, SPM-1, and AIM-1) that currently have impact in clinics. Therefore, low antibiotic impacted marine environment, as the ocean, are unlikely the source of ARGs that have been causing enormous threat to the public health.
Arsenic mobilization from solid phase Fe (III) hydroxides is an issue of concern, as water-borne arsenic can migrate into pristine environments, endangering aquatic and human life. In general, metal oxide (hydroxides) exerts a dominating effect on the fate and transport of arseni...
Phosphorus-bearing materials as an additive have been popularly used in nanomaterial synthesis and the residual phosphorus within the nanoparticles (NPs) can be of an environmental concern. For instance, phosphorus within pristine commercial TiO2 NPs greatly influences the surfac...
A Life Cycle Based Approach to Multi-Hazard Risk Assessment
NASA Astrophysics Data System (ADS)
Keen, A. S.; Lynett, P. J.
2017-12-01
Small craft harbors are important facets to many coastal communities providing a transition from land to ocean. Because of the damage resulting from the 2010 Chile and 2011 Japanese tele-tsunamis, the tsunami risk to the small craft marinas in California has become an important concern. However, tsunamis represent only one of many hazards a harbor is likely to see in California. Other natural hazards including tsunamis, wave attack, storm surge and sea level rise all can damage a harbor but are not typically addressed in traditional risk studies. Existing approaches to assess small craft harbor vulnerably typically look at single events assigning likely damage levels to each event. However, a harbor will likely experience damage from several different types of hazards over its service life with each event contributing proportionally to the total damage state. A new, fully probabilistic risk method will be presented which considers the distribution of return period for various hazards over a harbor's service life. The likelihood of failure is connected to each hazard via vulnerability curves. By simply tabulating the expected damage levels from each event, the method provides a quantitative measure of a harbor's risk to various types of hazards as well as the likelihood of failure (i.e. cumulative risk) during the service life. Crescent City Harbor in Northern California and Kings Harbor in Southern California have been chosen as case studies. Each harbor is dynamically different and were chosen to highlight the strengths and weaknesses of the method. Findings of each study will focus on assisting the stakeholders and decision makers to better understand the relative risk to each harbor with the goal of providing them with a tool to better plan for the future maritime environment.
Temporal assessment of microbial communities in soils of two contrasting mangroves.
Rigonato, Janaina; Kent, Angela D; Gumiere, Thiago; Branco, Luiz Henrique Zanini; Andreote, Fernando Dini; Fiore, Marli Fátima
Variations in microbial communities promoted by alterations in environmental conditions are reflected in similarities/differences both at taxonomic and functional levels. Here we used a natural gradient within mangroves from seashore to upland, to contrast the natural variability in bacteria, cyanobacteria and diazotroph assemblages in a pristine area compared to an oil polluted area along a timespan of three years, based on ARISA (bacteria and cyanobacteria) and nifH T-RFLP (diazotrophs) fingerprinting. The data presented herein indicated that changes in all the communities evaluated were mainly driven by the temporal effect in the contaminated area, while local effects were dominant on the pristine mangrove. A positive correlation of community structure between diazotrophs and cyanobacteria was observed, suggesting the functional importance of this phylum as nitrogen fixers in mangroves soils. Different ecological patterns explained the microbial behavior in the pristine and polluted mangroves. Stochastic models in the pristine mangrove indicate that there is not a specific environmental factor that determines the bacterial distribution, while cyanobacteria and diazotrophs better fitted in deterministic model in the same area. For the contaminated mangrove site, deterministic models better represented the variations in the communities, suggesting that the presence of oil might change the microbial ecological structures over time. Mangroves represent a unique environment threatened by global change, and this study contributed to the knowledge of the microbial distribution in such areas and its response on persistent contamination historic events. Copyright © 2017 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.
Sulfate-Reducing Naphthalene Degraders Are Picky Eaters.
Wolfson, Sarah J; Porter, Abigail W; Kerkhof, Lee J; McGuinness, Lora M; Prince, Roger C; Young, Lily Y
2018-06-25
Polycyclic aromatic hydrocarbons (PAHs) are common organic contaminants found in anoxic environments. The capacity for PAH biodegradation in unimpacted environments, however, has been understudied. Here we investigate the enrichment, selection, and sustainability of a microbial community from a pristine environment on naphthalene as the only amended carbon source. Pristine coastal sediments were obtained from the Jacques Cousteau National Estuarine Research Reserve in Tuckerton, New Jersey, an ecological reserve which has no direct input or source of hydrocarbons. After an initial exposure to naphthalene, primary anaerobic transfer cultures completely degraded 500 µM naphthalene within 139 days. Subsequent transfer cultures mineralized naphthalene within 21 days with stoichiometric sulfate loss. Enriched cultures efficiently utilized only naphthalene and 2-methylnaphthalene from the hydrocarbon mixtures in crude oil. To determine the microorganisms responsible for naphthalene degradation, stable isotope probing was utilized on cultures amended with fully labeled 13 C-naphthalene as substrate. Three organisms were found to unambiguously synthesize 13 C-DNA from 13 C-naphthalene within 7 days. Phylogenetic analysis revealed that 16S rRNA genes from two of these organisms are closely related to the known naphthalene degrading isolates NaphS2 and NaphS3 from PAH-contaminated sites. A third 16S rRNA gene was only distantly related to its closest relative and may represent a novel naphthalene degrading microbe from this environment.
Automatic detection of small surface targets with electro-optical sensors in a harbor environment
NASA Astrophysics Data System (ADS)
Bouma, Henri; de Lange, Dirk-Jan J.; van den Broek, Sebastiaan P.; Kemp, Rob A. W.; Schwering, Piet B. W.
2008-10-01
In modern warfare scenarios naval ships must operate in coastal environments. These complex environments, in bays and narrow straits, with cluttered littoral backgrounds and many civilian ships may contain asymmetric threats of fast targets, such as rhibs, cabin boats and jet-skis. Optical sensors, in combination with image enhancement and automatic detection, assist an operator to reduce the response time, which is crucial for the protection of the naval and land-based supporting forces. In this paper, we present our work on automatic detection of small surface targets which includes multi-scale horizon detection and robust estimation of the background intensity. To evaluate the performance of our detection technology, data was recorded with both infrared and visual-light cameras in a coastal zone and in a harbor environment. During these trials multiple small targets were used. Results of this evaluation are shown in this paper.
Knebel, Harley J.; Circe, Ronald C.
1995-01-01
This report illustrates, describes, and briefly discusses the acoustic and textural characteristics and the distribution of bottom sedimentary environments in Boston Harbor and Massachusetts Bay. The study is an outgrowth of a larger research program designed to understand the regional processes that distribute sediments and related contaminants in the area. The report highlights the major findings presented in recent papers by Knebel and others (1991), Knebel, (1993), and Knebel and Circe (1995). The reader is urged to consult the full text of these earlier papers for a more definitive treatment of the data and for appropriate supporting references.
A clamp fixture with interdigital capacitive sensor for in situ evaluation of wire insulation
NASA Astrophysics Data System (ADS)
Sheldon, Robert T.; Bowler, Nicola
2014-02-01
An interdigital capacitive sensor has been designed and optimized for testing aircraft wires by applying a quasinumerical model developed and reported previously. The sensor consists of two patches of interdigitated electrodes, connected by a long signal bus strip, that are intended to conform to two sides of an insulated wire. The electrodes are deposited using photolithography upon a 25.4-μm-thick Kapton® polyimide film. The two electrode patches are attached to the two jaws of a plastic spring-loaded clamp, with each jaw having a milled groove designed such that the electrodes conform to the curved surface of the insulated wire. An SMA connector and cable connect between the electrodes on the clamp and an LCR meter. Segments of pristine M5086/2 aircraft wire, each 10 cm long, were immersed in fluids commonly found in aircraft environments, to cause accelerated chemical degradation. The effects of Jet A fuel, deicing fluid, hydraulic fluid, aircraft cleaner, isopropyl alcohol and distilled water were studied. The frequency-dependent capacitance and dissipation factor of one pristine wire segment and of those degraded in the six fluid environments were measured within the frequency range 100 Hz to 1 MHz. Significant changes in capacitance and dissipation factor were observed for all degraded wires, compared with results for the pristine sample, suggesting the feasibility of detecting insulation degradation in the field. The results were also consistent with those of a similar experiment performed on sheets of Nylon 6, the material that comprises the outermost layer of M5086/2 wire.
The possible presence of ultra-trace levels (sub- parts per trillion) of pesticides in pristine aquatic environments (e.g., alpine lakes) would raise questions regarding potential effects on biota. One hypothesis is that agricultural pesticides that are heavily applied in the San...
Organohalide respiration in pristine environments: implications for the natural halogen cycle.
Atashgahi, Siavash; Häggblom, Max M; Smidt, Hauke
2018-03-01
Halogenated organic compounds, also termed organohalogens, were initially considered to be of almost exclusively anthropogenic origin. However, over 5000 naturally synthesized organohalogens are known today. This has also fuelled the hypothesis that the natural and ancient origin of organohalogens could have primed development of metabolic machineries for their degradation, especially in microorganisms. Among these, a special group of anaerobic microorganisms was discovered that could conserve energy by reducing organohalogens as terminal electron acceptor in a process termed organohalide respiration. Originally discovered in a quest for biodegradation of anthropogenic organohalogens, these organohalide-respiring bacteria (OHRB) were soon found to reside in pristine environments, such as the deep subseafloor and Arctic tundra soil with limited/no connections to anthropogenic activities. As such, accumulating evidence suggests an important role of OHRB in local natural halogen cycles, presumably taking advantage of natural organohalogens. In this minireview, we integrate current knowledge regarding the natural origin and occurrence of industrially important organohalogens and the evolution and spread of OHRB, and describe potential implications for natural halogen and carbon cycles. © 2017 Society for Applied Microbiology and John Wiley & Sons Ltd.
Interventions for fresh produce
USDA-ARS?s Scientific Manuscript database
Environmental matrices such as soil, water, and dust harbor microorganisms. Many of the microorganisms found in the environment are essential for biogeochemical cycles and are essential for plant growth. The microbiome of the produce production environment might also contain foodborne pathogens and ...
1. ENVIRONMENT, FROM SOUTH, SHOWING BOSTON STREET BRIDGE CARRYING BOSTON ...
1. ENVIRONMENT, FROM SOUTH, SHOWING BOSTON STREET BRIDGE CARRYING BOSTON STREET OVER HARRIS CREEK SEWER OUTLET AT NORTHWEST BRANCH OF PATAPSCO RIVER (BALTIMORE HARBOR) - Boston Street Bridge, Spanning Harris Creek Sewer at Boston Street, Baltimore, Independent City, MD
Code of Federal Regulations, 2010 CFR
2010-01-01
... most pristine atolls in the world. The lands, submerged lands, waters, and marine environment around... supports most of the seabird population of American Samoa, including 12 federally protected migratory... relatively undisturbed islands remain in the world and Rose Atoll is one of the last remaining refuges for...
Integrated approach to assess ecosystem health in harbor areas.
Bebianno, M J; Pereira, C G; Rey, F; Cravo, A; Duarte, D; D'Errico, G; Regoli, F
2015-05-01
Harbors are critical environments with strategic economic importance but with potential environmental impact: health assessment criteria are a key issue. An ecosystem health status approach was carried out in Portimão harbor as a case-study. Priority and specific chemical levels in sediments along with their bioavailability in mussels, bioassays and a wide array of biomarkers were integrated in a biomarker index (IBR index) and the overall data in a weight of evidence (WOE) model. Metals, PAHs, PCBs and HCB were not particularly high compared with sediment guidelines and standards for dredging. Bioavailability was evident for Cd, Cu and Zn. Biomarkers proved more sensitive namely changes of antioxidant responses, metallothioneins and vittellogenin-like proteins. IBR index indicated that site 4 was the most impacted area. Assessment of the health status by WOE approach highlighted the importance of integrating sediment chemistry, bioaccumulation, biomarkers and bioassays and revealed that despite some disturbance in the harbor area, there was also an impact of urban effluents from upstream. Environmental quality assessment in harbors. Copyright © 2015 Elsevier B.V. All rights reserved.
Campbell, Jacob B; Nath, Rachna; Gadau, Juergen; Fox, Trevor; DeGrandi-Hoffman, Gloria; Harrison, Jon F
2016-03-01
Honey bees and other pollinators are exposed to fungicides that act by inhibiting fungal mitochondria. Here we test whether a common fungicide (Pristine®) inhibits the function of mitochondria of honeybees, and whether consumption of ecologically-realistic concentrations can cause negative effects on the mitochondria of flight muscles, or the capability for flight, as judged by CO2 emission rates and thorax temperatures during flight. Direct exposure of mitochondria to Pristine® levels above 5 ppm strongly inhibited mitochondrial oxidation rates in vitro. However, bees that consumed pollen containing Pristine® at ecologically-realistic concentrations (≈ 1 ppm) had normal flight CO2 emission rates and thorax temperatures. Mitochondria isolated from the flight muscles of the Pristine®-consuming bees had higher state 3 oxygen consumption rates than control bees, suggesting that possibly Pristine®-consumption caused compensatory changes in mitochondria. It is likely that the lack of a strong functional effect of Pristine®-consumption on flight performance and the in vitro function of flight muscle mitochondria results from maintenance of Pristine® levels in the flight muscles at much lower levels than occur in the food, probably due to metabolism and detoxification. As Pristine® has been shown to negatively affect feeding rates and protein digestion of honey bees, it is plausible that Pristine® consumption negatively affects gut wall function (where mitochondria may be exposed to higher concentrations of Pristine®). Copyright © 2015 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Stiros, Stathis; Saltogianni, Vasso
2017-04-01
Tectonically active terrains are characterized by seismic transient ground motions (shaking) and by permanent ground motions in the vicinity of activated faults, with both effects occasionally leaving their signature on human constructions and the landscape. Especially in coastal areas marked by small tidal ranges and normal water salinity, as is the case with most parts of the Eastern Mediterranean, even small-amplitude tectonic motions can be derived from observations on coastal constructions, mainly harbors, but also on spring chambers in nearly arid environments, sewers, etc. Such observations, if coupled with well-dated observations of destructions and repairs and of changes in the occupation style of ancient sites can permit precious information conveyed from archaeology to tectonics/seismology and vice versa. A transect with harbor remains from Rhodes to the Gulf of Corinth and then till the Ionian Islands provides some excellent examples. The military harbor of Rhodes, in an area of long term uplift, a coded report of which seems to be provided by ancient poet Pindar, was subject to seismic subsidence and destruction, but with major international support, it was repaired, till renewed uplift brought it several meters above the water. In the Corinth area, the Kenchreai harbor was abruptly submerged during a major repair of a temple, as revealed by precious stained glass panels, ready to use but abandoned in shallow water beneath ruins, while radiometric dating of the uplift in the western Lechaion harbor, constrains its excavation in swampy environment not in Roman times, but to the period of flourishing of Corinth in circa 600BC and the colonization of Italy. Farther west, the sea-level mark of the harbor of Aigeira, at Mavra Litharia (Derveni/Akrata) indicates 4m uplift since the Roman period, at least partly seismic, correlating with an exposed reef and the abandonment of the repairs of the theatre of Aigeira. Seismic land uplift explains the demise of this ancient town since approximately AD200 as a result of loss of the only significant harbor along the southern coast of the Gulf of Corinth. Farther west, in the south part of the Greek mainland, rising of the level of the dock shortly after its construction may imply response to seismic land subsidence, while at the nearby harbor of Palairos, remains of a submerged breakwater, offset by several meters, testify to strike slip faulting with seismic offset amplified by liquefaction.
The possibility that chronic, multigenerational exposure to environmental estrogens selects for adaptive hormone response phenotypes is a critical unanswered question. Embryos/larvae of killifish from an estrogenic polluted environment (New Bedford Harbor, NBH), as compared to th...
Big Bay Harbor Operation and Maintenance Activities, Marquette County, Michigan.
1975-04-01
and Custom House St. Paul, Minnesota 55101 April 1975 ENVIRON1ENTAL ASSESSMENT REPORT OPERATION AND MAINTENANCE BIG BAY HARBOR BIG BAY, MICHIGAN LAKE...these parameters is important because of the deleterious effects of the parent and breakdown products. The presence of heavy metals, taconite tailings...iron mines further south in the county. 2.522 Powell Township is governed by a town supervisor and town board, all of whom are elected. The town owns a
Distribution and Fate of Tributyltin in the United States Marine Environment
Tributyltin ( TBT ) has been measured in water in 12 of 15 harbors studied during U.S. Navy baseline surveys. The highest concentrations of TBT (some...no detectable (5 ng dm-3) TBT . TBT monitoring studies with increased detection limits (l ng dm-3) have documented a high degree of TBT variability...associated with tide, season and intermittent point source discharges. Although yacht harbors were shown to be the principal TBT source in most regions
Bivalve embryo bioassay to assess the potential toxicity of dredged material before dumping
DOE Office of Scientific and Technical Information (OSTI.GOV)
Quiniou, F.
1995-12-31
Dredged harbor sediments frequently contain a wide spectrum of contaminants in addition to a significant percentage of organic matter. Also, dredging and dumping activities into sea water, of these highly contaminated soil may induce a harmful effect on the environment. In France, in accordance with Oslo convention guidelines, a working group on dredging activities and environment (GEODE) created since 1991 decided to set up a pilot research program to assess the intrinsic toxicity of four harbor sludges. Intrinsic toxicity of harbor muds were tested by solid phase (whole sediment) and aqueous extract bioassays (sea water elutriates) using the sublethal toxicitymore » test bivalve embryo bioassay (Crassostrea gigas). Elutriates enable them to detect the toxicity of contaminants which may be released in the soluble form into the water column during dredging operations. While, whole sediment integrate the synergistic effects of all the contaminants (hydrophilic and hydrophobic) including pore water. Bioassays results, correlated to chemical analysis, are compared to contaminant levels determined by French working group GEODE and Canadian sediment quality criteria.« less
Validation and verification of a virtual environment for training naval submarine officers
NASA Astrophysics Data System (ADS)
Zeltzer, David L.; Pioch, Nicholas J.
1996-04-01
A prototype virtual environment (VE) has been developed for training a submarine officer of the desk (OOD) to perform in-harbor navigation on a surfaced submarine. The OOD, stationed on the conning tower of the vessel, is responsible for monitoring the progress of the boat as it negotiates a marked channel, as well as verifying the navigational suggestions of the below- deck piloting team. The VE system allows an OOD trainee to view a particular harbor and associated waterway through a head-mounted display, receive spoken reports from a simulated piloting team, give spoken commands to the helmsman, and receive verbal confirmation of command execution from the helm. The task analysis of in-harbor navigation, and the derivation of application requirements are briefly described. This is followed by a discussion of the implementation of the prototype. This implementation underwent a series of validation and verification assessment activities, including operational validation, data validation, and software verification of individual software modules as well as the integrated system. Validation and verification procedures are discussed with respect to the OOD application in particular, and with respect to VE applications in general.
Physicochemical characteristics of pristine and functionalized graphene.
Bourdo, Shawn E; Al Faouri, Radwan; Sleezer, Robert; Nima, Zeid A; Lafont, Andersen; Chhetri, Bijay P; Benamara, Mourad; Martin, Betty; Salamo, Gregory J; Biris, Alexandru S
2017-11-01
Graphene-based nanomaterials have received significant attention in the last decade due to their interesting properties. Its electrical and thermal conductivity and strength make graphene well suited for a variety of applications, particularly for use as a composite material in plastics. Furthermore, much work is taking place to utilize graphene as a biomaterial for uses such as drug delivery and tissue regeneration scaffolds. Owing to the rapid progress of graphene and its potential in many marketplaces, the potential toxicity of these materials has garnered attention. Graphene, while simple in its purest form, can have many different chemical and physical properties. In this paper, we describe our toxicity evaluation of pristine graphene and a functionalized graphene sample that has been oxidized for enhanced hydrophilicity, which was synthesized from the pristine sample. The samples were characterized by X-ray photoelectron spectroscopy, Raman spectroscopy, infrared spectroscopy, thermogravimetric analysis, zeta-potential, atomic force microscopy and electron microscopy. We discuss the disagreement between the size of imaged samples analyzed by atomic force microscopy and by transmission electron microscopy. Furthermore, the samples each exhibit quite different surface chemistry and structure, which directly affects their interaction with aqueous environments and is important to consider when evaluating the toxicity of materials both in vitro and in vivo. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.
Wang, Ruoxi; Zhang, Dongju; Liu, Chengbu
2017-02-01
Polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) are highly toxic to humans and the environment. Developing efficient methods to detect or remove these pollutants is particularly important and urgent. Boron nitride nanotubes (BNNTs) with low dimension and high surface-to-volume ratio might be one of promising materials for the adsorption of PCDD/Fs. Here we present a density functional theory (DFT) study on the interaction of the pristine and Ni doped (8,0) single-walled BNNTs with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), the most toxic congener among PCDD/F family. The calculated results show that the pristine BNNT intrinsically interacts with TCDD via physisorption with π-π stacking interaction, in contrast, the Ni-doped BNNT presents much higher reactivities toward TCDD. The impurity Ni atom plays a crucial role for capturing TCDD molecule. We also find that the Ni doping introduces the local electronic states within the band gap of the BNNT and induces magnetism in the doped systems. The present results are expected to provide useful guidance for the potential application of BNNTs as adsorption materials for detecting or removing dioxin pollutants. Copyright © 2016 Elsevier Ltd. All rights reserved.
Rust and schreibersite in Apollo 16 highland rocks - Manifestations of volatile-element mobility
NASA Technical Reports Server (NTRS)
Hunter, R. H.; Taylor, L. A.
1982-01-01
Rust is a manifestation of halogen and volatile-metal mobility in the lunar environment. Schreibersite is stable as the primary phosphorus-bearing phase in the highland rocks, a consequence of the inherently low oxygen fugacity within impact-generated melts. Apatite and whitlockite are subordinate in these rocks. The partitioning of P into phosphide in impact-generated melts, and the failure of phosphate to crystallize, effects a decoupling of the halogens and phosphorus. Of the Apollo 16 rocks, 63% contain rust, 70% contain schreibersite, and 52% contain both phases, thereby establishing the pervasiveness of volatile-elements throughout the highland rocks. The major portion of these volatile-bearing phases occur in impact melt-rocks or in breccia matrices. Rhabdites of schreibersite in some of the FeNi grains indicate that there is a meteoritic contribution to the phosphorus in these rocks. Cl/P2O5 ratios in lunar highland rocks are a function of secondary effects, with any apparent Cl-P correlations being coincidential. The present observations preclude the validity of models based on such elemental ratios in these rocks. The presence of rust in the clast laden matrices of pristine rocks indicates fugitive element localization. Pristine clasts may have been contaminated. The basis for a pristine volatile chemistry is questioned.
Federal Register 2010, 2011, 2012, 2013, 2014
2010-11-03
... Chief, Environmental Enforcement Section, Environment and Natural Resources Division. [FR Doc. 2010... Debtor's Portland Harbor Superfund Site; and (3) natural resource damages and assessment costs, incurred... should be addressed to the Acting Assistant Attorney General, Environment and Natural Resources Division...
Pre-Flight Characterization of Samples for the MISSE-7 Spacesuit Fabric Exposure Experiment
NASA Technical Reports Server (NTRS)
Gaier, James R.; McCue, Terry R.; Clark, Gregory W.; Rogers, Kerry J.; Mengesu, Tsega
2009-01-01
A series of six sample spacesuit pressure garment assembly (PGA) fabric samples were prepared for the Materials International Space Station Experiment 7 (MISSE-7) flight experiment to test the effects of damage by lunar dust on the susceptibility of the fabrics to radiation damage. These included pristine Apollo-era fluorinated ethylene-propylene (FEP) fabric, Apollo-era FEP fabric that had been abraded with JSC-1A lunar simulant, and a piece of Alan Bean s Apollo 12 PGA sectioned from near the left knee. Also included was a sample of pristine orthofabric, and orthofabric that had been abraded to two different levels with JSC-1A. The samples were characterized using optical microscopy, field emission scanning electron microscopy, and atomic force microscopy. Two sets of six samples were then loaded in space environment exposure hardware, one of which was stored as control samples. The other set was affixed to the MISSE-7 experiment package, and will be mounted on the International Space Station, and exposed to the wake-side low Earth orbit environment. It will be retrieved after an exposure of approximately 12 months, and returned for post flight analysis.
NASA Astrophysics Data System (ADS)
Herzyk, Agnieszka; Fillinger, Lucas; Larentis, Michael; Qiu, Shiran; Maloszewski, Piotr; Hünniger, Marko; Schmidt, Susanne I.; Stumpp, Christine; Marozava, Sviatlana; Knappett, Peter S. K.; Elsner, Martin; Meckenstock, Rainer; Lueders, Tillmann; Griebler, Christian
2017-12-01
Microbial communities are the driving force behind the degradation of contaminants like aromatic hydrocarbons in groundwater ecosystems. However, little is known about the response of native microbial communities to contamination in pristine environments as well as their potential to recover from a contamination event. Here, we used an indoor aquifer mesocosm filled with sandy quaternary calciferous sediment that was continuously fed with pristine groundwater to study the response, resistance and resilience of microbial communities to toluene contamination over a period of almost two years, comprising 132 days of toluene exposure followed by nearly 600 days of recovery. We observed an unexpectedly high intrinsic potential for toluene degradation, starting within the first two weeks after the first exposure. The contamination led to a shift from oxic to anoxic, primarily nitrate-reducing conditions as well as marked cell growth inside the contaminant plume. Depth-resolved community fingerprinting revealed a low resistance of the native microbial community to the perturbation induced by the exposure to toluene. Distinct populations that were dominated by a small number of operational taxonomic units (OTUs) rapidly emerged inside the plume and at the plume fringes, partially replacing the original community. During the recovery period physico-chemical conditions were restored to the pristine state within about 35 days, whereas the recovery of the biological parameters was much slower and the community composition inside the former plume area had not recovered to the original state by the end of the experiment. These results demonstrate the low resilience of sediment-associated groundwater microbial communities to organic pollution and underline that recovery of groundwater ecosystems cannot be assessed solely by physico-chemical parameters.
Herzyk, Agnieszka; Fillinger, Lucas; Larentis, Michael; Qiu, Shiran; Maloszewski, Piotr; Hünniger, Marko; Schmidt, Susanne I; Stumpp, Christine; Marozava, Sviatlana; Knappett, Peter S K; Elsner, Martin; Meckenstock, Rainer; Lueders, Tillmann; Griebler, Christian
2017-12-01
Microbial communities are the driving force behind the degradation of contaminants like aromatic hydrocarbons in groundwater ecosystems. However, little is known about the response of native microbial communities to contamination in pristine environments as well as their potential to recover from a contamination event. Here, we used an indoor aquifer mesocosm filled with sandy quaternary calciferous sediment that was continuously fed with pristine groundwater to study the response, resistance and resilience of microbial communities to toluene contamination over a period of almost two years, comprising 132days of toluene exposure followed by nearly 600days of recovery. We observed an unexpectedly high intrinsic potential for toluene degradation, starting within the first two weeks after the first exposure. The contamination led to a shift from oxic to anoxic, primarily nitrate-reducing conditions as well as marked cell growth inside the contaminant plume. Depth-resolved community fingerprinting revealed a low resistance of the native microbial community to the perturbation induced by the exposure to toluene. Distinct populations that were dominated by a small number of operational taxonomic units (OTUs) rapidly emerged inside the plume and at the plume fringes, partially replacing the original community. During the recovery period physico-chemical conditions were restored to the pristine state within about 35days, whereas the recovery of the biological parameters was much slower and the community composition inside the former plume area had not recovered to the original state by the end of the experiment. These results demonstrate the low resilience of sediment-associated groundwater microbial communities to organic pollution and underline that recovery of groundwater ecosystems cannot be assessed solely by physico-chemical parameters. Copyright © 2017 Elsevier B.V. All rights reserved.
1995-06-01
putative virulence factors of H. pylori have been identified to date. These factors include a urease , flagella, a mucinase, a cytotoxin, and two adhesins...The urease is believed to aid in bacterial survival of the harsh gastric environment by generating ammonia from urea to neutralize the low pH (Segal...A Laboratory Manual. Cold Spring Harbor, New York. Cold Spring Harbor Laboratory Press. Hazell, S., A. Lee. 1986. Campylobacter pyloridis urease
Super Shedding of Escherichia coli O157:H7 by Cattle and the Impact on Beef Carcass Contamination
USDA-ARS?s Scientific Manuscript database
Beef carcass contamination is a direct result of pathogen transfer from cattle hides harboring organisms such as enterohemorrhagic E. coli. Hide contamination occurs from direct and indirect fecal contamination in cattle production and lairage environments. In each of these environments, individua...
A smart ROV solution for ship hull and harbor inspection
NASA Astrophysics Data System (ADS)
Reed, Scott; Wood, Jon; Vazquez, Jose; Mignotte, Pierre-Yves; Privat, Benjamin
2010-04-01
Hull and harbor infrastructure inspections are frequently performed manually and involve quite a bit of risk and human and monetary resources. In any kind of threat and resource constrained environment, this involves unacceptable levels of risk and cost. Modern Remotely Operated Vehicles are highly refined machines that provide features and capabilities previously unavailable. Operations once carried out by divers can now be carried out more quickly, efficiently and safely by smart enabled ROVs. ROVs are rapidly deployable and capable of continuous, reliable operations in adverse conditions. They also provide a stable platform on which multiple sensors may be mounted and utilized to meet the harbor inspection problem. Automated Control software provides ROV's and their pilots with the capability to inspect complex, constrained environments such as those found in a harbor region. This application and the user interface allow the ROV to automatically conduct complex maneuvers relative to the area being inspected and relieves the training requirements and work load for the pilot, allowing he or she to focus on the primary task of survey, inspection and looking for possible threats (such as IEDs, Limpet Mines, signs of sabotage, etc). Real-time sensor processing tools can be integrated into the smart ROV solution to assist the operator. Automatic Target Recognition (ATR) algorithms are used to search through the sensor data collected by the ROV in real time. These algorithms provide immediate feedback on possible threats and notify the operator of regions that may require manual verification. Sensor data (sonar or video) is also mosaiced, providing the operator with real-time situational awareness and a coverage map of the hull or seafloor. Detected objects may also be placed in the context of the large scale characteristics of the hull (or bottom or pilings) and localized. Within the complex areas such as the harbor pier pilings and the running gear of the ship, real-time 3D reconstruction techniques may be used to process profiling sonar data for similar applications. An observation class ROV equipped with sensors, running an operator in the loop, Automated Surface-Computer (ASC) system can inspect an entire harbor region. These systems can autonomously provide coverage information, identify possible threats and provide the level of control required to operate in confined environments. The system may be controlled autonomously or by the operator. Previous inspection results may also be used for change detection applications. This paper presents the SeeByte Smart ROV and sensor processing technology relevant to the harbor inspection problem. These technologies have been tested extensively in real world applications and trials and are demonstrated using real data and examples.
Water quality of a port in NW Mexico and its rehabilitation with swell energy.
de la Lanza Espino, Guadalupe; Rodríguez, Iván Penié; Czitrom, Steven P R
2010-01-01
Ensenada Harbor is one of the most important ports of Mexico. Anthropogenic activities have affected the area over several decades, leading to the accumulation of contaminants in its sediments, which eventually are re-suspended into the water column. In spite of water treatment of the tributaries that discharge into the Ensenada Harbor, the water circulation patterns of the harbor, which consist of closed eddies in the northern and southeastern sector, favor the accumulation of those contaminants and hinder exchange with adjacent seawater. Samples collected in October of 2005 registered 63 microM total inorganic nitrogen and 280 mg/L of COD, confirming that this is a highly contaminated environment when compared with other water bodies of North America. Such concentrations can be lowered up to 80% by using a wave energy pumping system that demonstrates the possibility to gradually dilute these contaminants and rehabilitate the Ensenada Harbor. Copyright 2009 Elsevier Ltd. All rights reserved.
Shell shape as a biomarker of marine pollution historic increase.
Márquez, F; Primost, M A; Bigatti, G
2017-01-30
Buccinanops globulosus is a TBT sensitive marine gastropod, classified as a good indicator of imposex incidence and used as a model to study adverse contamination effects. Population and maritime industries has incremented pollution in Nuevo gulf harbor since 1970s, promoting morphological changes in B. globulosus shell shape. We study the shell shape of the species comparing present day's specimens from the harbor zone with those collected in the same zone before the increasing of maritime activity and pre-Hispanic archaeological Middens. We demonstrated that harbor pollution produces globular shell shape in B. globulosus, an effect that probably allows gastropods to isolate themselves from the external adverse environment. On the contrary, shells from pre-Hispanic periods, unpolluted sites and those collected before the expansion of maritime activities, presented an elongated shell shape. Our study confirms that shell shape variation in marine gastropods can be used as a biomarker of harbor pollution. Copyright © 2016 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Spergel, J.; Kimball, K. C.; Fitzpatrick, S. A.; Michelson, A. V.; Leonard-Pingel, J.
2015-12-01
Lake ecosystems face a multitude of environmental threats including: eutrophication, overfishing, and heavy metal pollution. Tools to identify lakes impacted by human activity and quantify that impact are needed to combat their environmental degradation. One such promising tool has been the comparison between living communities and associated time-averaged death assemblages of mollusks in marine environments. Here we extend the reach of such live/dead comparisons using ostracodes in temperate lakes. We sampled six lakes in Wisconsin for living communities and associated death assemblages of ostracodes: two lakes impacted by human activity, two relatively "pristine" lakes, and two remediated lakes. We took sixteen grab samples of the upper centimeter of sediment in each lake, capturing simultaneously living benthic ostracodes and discarded valves of dead ostracodes. We found that impacted lakes had lower live/dead fidelity in taxonomic composition and rank-order abundance distributions and greater within-lake variation in death assemblages than "pristine" lakes. Additionally, the living communities in the impacted lakes tended to be lower in species richness and have lower evenness than "pristine" lakes. Remediated lakes displayed similar live/dead fidelity in taxonomic composition and rank-abundance distributions to "pristine" lakes and had lower within-lake variation in death assemblages than impacted lakes. Remediated lakes also contained living communities that tended to be richer and more even than impacted lakes. The lower live/dead fidelity of ostracodes in impacted lakes indicate live/dead ostracode comparisons can provide a tool to identify lake ecosystems impacted by humans. The similar results of remediated and "pristine" lakes indicate remediation efforts in these lakes have been successful in alleviating environmental impact detrimental to ostracode communities. This result indicates live/dead comparisons of ostracodes can be a useful tool to monitor the progress of remediation efforts already underway. Further work will focus on dating the upper centimeter of sediment in these lakes to provide an estimate of how long it takes for death assemblages to accumulate and thus how long it will take to regain high live/dead fidelity in impacted lakes undergoing remediation.
Sandra E. Ryan; Mark K. Dixon
2007-01-01
Sediment transport rates (dissolved, suspended, and bedload) measured over the course of several years are reported for two streams in the Gros Ventre Mountain range in western Wyoming, USA: Little Granite and Cache Creeks. Both streams drain watersheds that are in relatively pristine environments. The sites are about 20km apart, have runoff dominated by snowmelt and...
Badalamenti, Fabio; Iveša, Ljiljana; Mikac, Barbara; Musco, Luigi; Jaklin, Andrej; Rattray, Alex; Vega Fernández, Tomás; Benedetti-Cecchi, Lisandro
2016-01-01
The difficulty in teasing apart the effects of biological invasions from those of other anthropogenic perturbations has hampered our understanding of the mechanisms underpinning the global biodiversity crisis. The recent elaboration of global-scale maps of cumulative human impacts provides a unique opportunity to assess how the impact of invaders varies among areas exposed to different anthropogenic activities. A recent meta-analysis has shown that the effects of invasive seaweeds on native biota tend to be more negative in relatively pristine than in human-impacted environments. Here, we tested this hypothesis through the experimental removal of the invasive green seaweed, Caulerpa cylindracea, from rocky reefs across the Mediterranean Sea. More specifically, we assessed which out of land-based and sea-based cumulative impact scores was a better predictor of the direction and magnitude of the effects of this seaweed on extant and recovering native assemblages. Approximately 15 months after the start of the experiment, the removal of C. cylindracea from extant assemblages enhanced the cover of canopy-forming macroalgae at relatively pristine sites. This did not, however, result in major changes in total cover or species richness of native assemblages. Preventing C. cylindracea re-invasion of cleared plots at pristine sites promoted the recovery of canopy-forming and encrusting macroalgae and hampered that of algal turfs, ultimately resulting in increased species richness. These effects weakened progressively with increasing levels of land-based human impacts and, indeed, shifted in sign at the upper end of the gradient investigated. Thus, at sites exposed to intense disturbance from land-based human activities, the removal of C. cylindracea fostered the cover of algal turfs and decreased that of encrusting algae, with no net effect on species richness. Our results suggests that competition from C. cylindracea is an important determinant of benthic assemblage diversity in pristine environments, but less so in species-poor assemblages found at sites exposed to intense disturbance from land-based human activities, where either adverse physical factors or lack of propagules may constrain the number of potential native colonizers. Implementing measures to reduce the establishment and spread of C. cylindracea in areas little impacted by land-based human activities should be considered a priority for preserving the biodiversity of Mediterranean shallow rocky reefs. PMID:27014513
Bulleri, Fabio; Badalamenti, Fabio; Iveša, Ljiljana; Mikac, Barbara; Musco, Luigi; Jaklin, Andrej; Rattray, Alex; Vega Fernández, Tomás; Benedetti-Cecchi, Lisandro
2016-01-01
The difficulty in teasing apart the effects of biological invasions from those of other anthropogenic perturbations has hampered our understanding of the mechanisms underpinning the global biodiversity crisis. The recent elaboration of global-scale maps of cumulative human impacts provides a unique opportunity to assess how the impact of invaders varies among areas exposed to different anthropogenic activities. A recent meta-analysis has shown that the effects of invasive seaweeds on native biota tend to be more negative in relatively pristine than in human-impacted environments. Here, we tested this hypothesis through the experimental removal of the invasive green seaweed, Caulerpa cylindracea, from rocky reefs across the Mediterranean Sea. More specifically, we assessed which out of land-based and sea-based cumulative impact scores was a better predictor of the direction and magnitude of the effects of this seaweed on extant and recovering native assemblages. Approximately 15 months after the start of the experiment, the removal of C. cylindracea from extant assemblages enhanced the cover of canopy-forming macroalgae at relatively pristine sites. This did not, however, result in major changes in total cover or species richness of native assemblages. Preventing C. cylindracea re-invasion of cleared plots at pristine sites promoted the recovery of canopy-forming and encrusting macroalgae and hampered that of algal turfs, ultimately resulting in increased species richness. These effects weakened progressively with increasing levels of land-based human impacts and, indeed, shifted in sign at the upper end of the gradient investigated. Thus, at sites exposed to intense disturbance from land-based human activities, the removal of C. cylindracea fostered the cover of algal turfs and decreased that of encrusting algae, with no net effect on species richness. Our results suggests that competition from C. cylindracea is an important determinant of benthic assemblage diversity in pristine environments, but less so in species-poor assemblages found at sites exposed to intense disturbance from land-based human activities, where either adverse physical factors or lack of propagules may constrain the number of potential native colonizers. Implementing measures to reduce the establishment and spread of C. cylindracea in areas little impacted by land-based human activities should be considered a priority for preserving the biodiversity of Mediterranean shallow rocky reefs.
Rodenburg, Lisa A; Krumins, Valdis; Curran, Joanna Crowe
2015-06-16
The Portland Harbor (Oregon, USA) has been declared a "Superfund" site because it is impacted by a variety of contaminants, including polychlorinated biphenyls (PCBs) and polychlorinated dibenzo-p-dioxins and -furans (PCDD/Fs). Using data collected in the remedial investigation, concentrations of PCBs and PCDD/Fs in sediment and water were examined using positive matrix factorization to look for evidence that PCBs and PCDD/Fs are dechlorinated by anaerobic bacteria. This process has long been known to occur in sediments. Recently, it has been recognized that PCB and PCDD/F dechlorination may also occur in other anaerobic environments, such as in landfills, sewers, and groundwater. The results indicate that a factor related to the dechlorination of PCBs and PCDD/Fs was present in the water but not in the sediment. Spatial patterns in dechlorination products suggest that they come primarily from groundwater. Dechlorination products comprise 22% of the PCBs in the water. The Portland Harbor therefore represents the third major US watershed in which PCBs appear to undergo dechlorination in an environment other than sediment, suggesting that the microbial dechlorination of PCBs and PCDD/Fs is more common than previously assumed. In addition, the Portland Harbor is impacted by PCBs generated inadvertently during the production of pigments, such as PCB 11, which alone exceeded the 64 pg/L federal water quality standard for the sum of PCBs in two of 120 whole water samples.
The New Bedford Harbor Superfund site long-term monitoring program (1993-2009).
Nelson, William G; Bergen, Barbara J
2012-12-01
New Bedford Harbor (NBH), located in southeastern Massachusetts, was designated as a marine Superfund site in 1983 due to sediment contamination by polychlorinated biphenyls (PCBs). Based on risks to human health and the environment, the first two phases of the site cleanup involved dredging PCB-contaminated sediments from the harbor. Therefore, a long-term monitoring program (LTM) was developed to measure spatial and temporal chemical and biological changes in sediment, water, and biota to assess the effects and effectiveness of the remedial activities. A systematic, probabilistic sampling design was used to select sediment sampling stations. This unbiased design allowed the three segments of the harbor to be compared spatially and temporally to quantify changes resulting from dredging the contaminated sediments. Sediment was collected at each station, and chemical (e.g., PCBs and metals), physical (e.g., grain size), and biological (e.g., benthic community) measurements were conducted on all samples. This paper describes the overall NBH-LTM approach and the results from the five rounds of sample collections. There is a decreasing spatial gradient in sediment PCB concentrations from the northern boundary (upper harbor) to the southern boundary (outer harbor) of the site. Along this same transect, there is an increase in biological condition (e.g., benthic community diversity). Temporally, the contaminant and biological gradients have been maintained since the 1993 baseline collection; however, since the onset of full-scale remediation, PCB concentrations have decreased throughout the site, and one of the benthic community indices has shown significant improvement in the lower and outer harbor areas.
Phytotoxins: environmental micropollutants of concern?
Bucheli, Thomas D
2014-11-18
Natural toxins such as mycotoxins or phytotoxins (bioactive compounds from fungi and plants, respectively) have been widely studied in food and feed, where they are stated to out-compete synthetic chemicals in their overall human and animal toxicological risk. A similar perception and awareness is yet largely missing for environmental safety. This article attempts to raise concern in this regard, by providing (circumstantial) evidence that phytotoxins in particular can be emitted into the environment, where they may contribute to the complex mixture of organic micropollutants. Exposures can be orders-of-magnitude higher in anthropogenically managed/affected (agro-)ecosystems than in the pristine environment.
A Comparison of Microbial Water Quality and Diversity for Ballast and Tropical Harbor Waters
Goh, Shin Giek; Liang, Liang; Kim, Yiseul; Rose, Joan B.; Yew-Hoong, Karina Gin
2015-01-01
Indicator organisms and antibiotic resistance were used as a proxy to measure microbial water quality of ballast tanks of ships, and surface waters in a tropical harbor. The survival of marine bacteria in ballast tanks appeared to diminish over longer water retention time, with a reduction of cell viability observed after a week based on heterotrophic plate counts. Pyrosequencing of 16S rRNA genes showed distinct differences in microbial composition of ballast and harbor waters. The harbor waters had a higher abundance of operational taxonomic units (OTUs) assigned to Cyanobacteria (Synechococcus spp.) and α-proteobacteria (SAR11 members), while marine hydrocarbon degraders such as γ-proteobacteria (Ocenspirillaes spp., Thiotrchales spp.) and Bacteroidetes (Flavobacteriales spp.) dominated the ballast water samples. Screening of indicator organisms found Escherichia coli (E. coli), Enterococcus and Pseudomonas aeruginosa (P. aeruginosa) in two or more of the ballast and harbor water samples tested. Vibrio spp. and Salmonella spp. were detected exclusively in harbor water samples. Using quantitative PCR (qPCR), we screened for 13 antibiotic resistant gene (ARG) targets and found higher abundances of sul1 (4.13–3.44 x 102 copies/mL), dfrA (0.77–1.80 x10 copies/mL) and cfr (2.00–5.21 copies/mL) genes compared to the other ARG targets selected for this survey. These genes encode for resistance to sulfonamides, trimethoprim and chloramphenicol-florfenicol antibiotics, which are also known to persist in sediments of aquaculture farms and coastal environments. Among the ARGs screened, we found significant correlations (P<0.05) between ereA, ermG, cfr and tetO genes to one or more of the indicator organisms detected in this study, which may suggest that these members contribute to the environmental resistome. This study provides a baseline water quality survey, quantitatively assessing indicators of antibiotic resistance, potentially pathogenic organisms and a broad-brush description of difference in microbial composition and diversity between open oceans and tropical coastal environments through the use of next generation sequencing technology. PMID:26575481
A Comparison of Microbial Water Quality and Diversity for Ballast and Tropical Harbor Waters.
Ng, Charmaine; Le, Thai-Hoang; Goh, Shin Giek; Liang, Liang; Kim, Yiseul; Rose, Joan B; Yew-Hoong, Karina Gin
2015-01-01
Indicator organisms and antibiotic resistance were used as a proxy to measure microbial water quality of ballast tanks of ships, and surface waters in a tropical harbor. The survival of marine bacteria in ballast tanks appeared to diminish over longer water retention time, with a reduction of cell viability observed after a week based on heterotrophic plate counts. Pyrosequencing of 16S rRNA genes showed distinct differences in microbial composition of ballast and harbor waters. The harbor waters had a higher abundance of operational taxonomic units (OTUs) assigned to Cyanobacteria (Synechococcus spp.) and α-proteobacteria (SAR11 members), while marine hydrocarbon degraders such as γ-proteobacteria (Ocenspirillaes spp., Thiotrchales spp.) and Bacteroidetes (Flavobacteriales spp.) dominated the ballast water samples. Screening of indicator organisms found Escherichia coli (E. coli), Enterococcus and Pseudomonas aeruginosa (P. aeruginosa) in two or more of the ballast and harbor water samples tested. Vibrio spp. and Salmonella spp. were detected exclusively in harbor water samples. Using quantitative PCR (qPCR), we screened for 13 antibiotic resistant gene (ARG) targets and found higher abundances of sul1 (4.13-3.44 x 102 copies/mL), dfrA (0.77-1.80 x10 copies/mL) and cfr (2.00-5.21 copies/mL) genes compared to the other ARG targets selected for this survey. These genes encode for resistance to sulfonamides, trimethoprim and chloramphenicol-florfenicol antibiotics, which are also known to persist in sediments of aquaculture farms and coastal environments. Among the ARGs screened, we found significant correlations (P<0.05) between ereA, ermG, cfr and tetO genes to one or more of the indicator organisms detected in this study, which may suggest that these members contribute to the environmental resistome. This study provides a baseline water quality survey, quantitatively assessing indicators of antibiotic resistance, potentially pathogenic organisms and a broad-brush description of difference in microbial composition and diversity between open oceans and tropical coastal environments through the use of next generation sequencing technology.
Barton, Lauren E; Auffan, Melanie; Bertrand, Marie; Barakat, Mohamed; Santaella, Catherine; Masion, Armand; Borschneck, Daniel; Olivi, Luca; Roche, Nicolas; Wiesner, Mark R; Bottero, Jean-Yves
2014-07-01
Engineered nanomaterials (ENMs) are used to enhance the properties of many manufactured products and technologies. Increased use of ENMs will inevitably lead to their release into the environment. An important route of exposure is through the waste stream, where ENMs will enter wastewater treatment plants (WWTPs), undergo transformations, and be discharged with treated effluent or biosolids. To better understand the fate of a common ENM in WWTPs, experiments with laboratory-scale activated sludge reactors and pristine and citrate-functionalized CeO2 nanoparticles (NPs) were conducted. Greater than 90% of the CeO2 introduced was observed to associate with biosolids. This association was accompanied by reduction of the Ce(IV) NPs to Ce(III). After 5 weeks in the reactor, 44 ± 4% reduction was observed for the pristine NPs and 31 ± 3% for the citrate-functionalized NPs, illustrating surface functionality dependence. Thermodynamic arguments suggest that the likely Ce(III) phase generated would be Ce2S3. This study indicates that the majority of CeO2 NPs (>90% by mass) entering WWTPs will be associated with the solid phase, and a significant portion will be present as Ce(III). At maximum, 10% of the CeO2 will remain in the effluent and be discharged as a Ce(IV) phase, governed by cerianite (CeO2).
Embrittlement of MISSE 5 Polymers After 13 Months of Space Exposure
NASA Technical Reports Server (NTRS)
Guo, Aobo; Yi, Grace T.; Ashmead, Claire C.; Mitchell, Gianna G.; deGroh, Kim K.
2012-01-01
Understanding space environment induced degradation of spacecraft materials is essential when designing durable and stable spacecraft components. As a result of space radiation, debris impacts, atomic oxygen interaction, and thermal cycling, the outer surfaces of space materials degrade when exposed to low Earth orbit (LEO). The objective of this study was to measure the embrittlement of 37 thin film polymers after LEO space exposure. The polymers were flown aboard the International Space Station and exposed to the LEO space environment as part of the Materials International Space Station Experiment 5 (MISSE 5). The samples were flown in a nadir-facing position for 13 months and were exposed to thermal cycling along with low doses of atomic oxygen, direct solar radiation and omnidirectional charged particle radiation. The samples were analyzed for space-induced embrittlement using a bend-test procedure in which the strain necessary to induce surface cracking was determined. Bend-testing was conducted using successively smaller mandrels to apply a surface strain to samples placed on a semi-suspended pliable platform. A pristine sample was also tested for each flight sample. Eighteen of the 37 flight samples experienced some degree of surface cracking during bend-testing, while none of the pristine samples experienced any degree of cracking. The results indicate that 49 percent of the MISSE 5 thin film polymers became embrittled in the space environment even though they were exposed to low doses (approx.2.75 krad (Si) dose through 127 mm Kapton) of ionizing radiation.
Shoaling of Aguadilla Harbor, Puerto Rico
2007-06-01
S. D. Nio, ed., Tide-influenced sedimentary environments and facies . D. Reidel Publishing Company, 275-288. Gao, S., and M. Collins. 1994...of STA to further their understanding of sedimentary environments . A number of authors found their results to agree, either in whole or in part, with...divided into three principal Transport Environments (TEs). Two of these comprised the north and south halves of Bahia de Aguadilla, and a third
The New Bedford Harbor Superfund Site Long Term ...
Background. New Bedford Harbor (NBH), located in southeastern Massachusetts, was designated as a marine Superfund site in 1983 due to sediment contamination by polychlorinated biphenyls (PCBs). Based on risks to human health and the environment, the first two phases of the site cleanup involved dredging PCB-contaminated sediments from the harbor. Therefore, a long-term monitoring program (LTM) was developed to measure spatial and temporal chemical and biological changes in sediment, water, and biota to assess the effects and effectiveness of the remedial activities. Approach. A systematic, probabilistic sampling design was used to select approximately 70 sediment sampling stations. Sediment was collected at each station and chemical (e.g., PCBs, metals), physical (e.g., grain size), and biological (e.g., benthic community) measurements were conducted on all samples. There have been six sample collections to date: 1993-baseline, 1995-post hot spot removal, 1999-prior to full scale dredging, and then at 5 year intervals: 2004, 2009, and 2014. Mussel (Mytilus edulis) bioaccumulation has also been measured twice yearly. Results. There is a decreasing spatial gradient in sediment PCB concentrations from the northern boundary (upper harbor) to the southern boundary (outer harbor) of the site. Along this same transect, there is an increase in biological condition (e.g., benthic community diversity). Temporally, the contaminant and biological gradients have been
Urbanisation and the loss of phylogenetic diversity in birds.
Sol, Daniel; Bartomeus, Ignasi; González-Lagos, César; Pavoine, Sandrine
2017-06-01
Despite the recognised conservation value of phylogenetic diversity, little is known about how it is affected by the urbanisation process. Combining a complete avian phylogeny with surveys along urbanisation gradients from five continents, we show that highly urbanised environments supported on average 450 million fewer years of evolutionary history than the surrounding natural environments. This loss was primarily caused by species loss and could have been higher had not been partially compensated by the addition of urban exploiters and some exotic species. Highly urbanised environments also supported fewer evolutionary distinctive species, implying a disproportionate loss of evolutionary history. Compared with highly urbanised environments, changes in phylogenetic richness and evolutionary distinctiveness were less substantial in moderately urbanised environments. Protecting pristine environments is therefore essential for maintaining phylogenetic diversity, but moderate levels of urbanisation still preserve much of the original diversity. © 2017 John Wiley & Sons Ltd/CNRS.
Federal Register 2010, 2011, 2012, 2013, 2014
2011-06-28
... the public, workers, and the environment. For example, the Board clarified that use of the term.... Department of Energy Nonreactor Nuclear Facility Documented Safety Analyses, as a safe harbor methodology..., our workers, and the environment at all of our facilities. We share your conviction that a clear set...
78 FR 29089 - Safety Zones; Hawaiian Island Commercial Harbors, HI
Federal Register 2010, 2011, 2012, 2013, 2014
2013-05-17
..., cause millions of dollars in property damage, and alter sensitive ecologies. The tsunami generated by... individually or cumulatively have a significant effect on the human environment. This rule will evacuate...
Sulphur Spring: Busy Intersection and Possible Martian Analogue
NASA Technical Reports Server (NTRS)
Nankivell, A.; Andre, N.; Thomas-Keprta, K.; Allen, C.; McKay, D.
2000-01-01
Life in extreme environments exhibiting conditions similar to early Earth and Mars, such as Sulphur Spring, may harbor microbiota serving as both relics from the past as well as present day Martian analogues.
Aging of microplastics promotes their ingestion by marine zooplankton.
Vroom, Renske J E; Koelmans, Albert A; Besseling, Ellen; Halsband, Claudia
2017-12-01
Microplastics (<5 mm) are ubiquitous in the marine environment and are ingested by zooplankton with possible negative effects on survival, feeding, and fecundity. The majority of laboratory studies has used new and pristine microplastics to test their impacts, while aging processes such as weathering and biofouling alter the characteristics of plastic particles in the marine environment. We investigated zooplankton ingestion of polystyrene beads (15 and 30 μm) and fragments (≤30 μm), and tested the hypothesis that microplastics previously exposed to marine conditions (aged) are ingested at higher rates than pristine microplastics. Polystyrene beads were aged by soaking in natural local seawater for three weeks. Three zooplankton taxa ingested microplastics, excluding the copepod Pseudocalanus spp., but the proportions of individuals ingesting plastic and the number of particles ingested were taxon and life stage specific and dependent on plastic size. All stages of Calanus finmarchicus ingested polystyrene fragments. Aged microbeads were preferred over pristine ones by females of Acartia longiremis as well as juvenile copepodites CV and adults of Calanus finmarchicus. The preference for aged microplastics may be attributed to the formation of a biofilm. Such a coating, made up of natural microbes, may contain similar prey as the copepods feed on in the water column and secrete chemical exudates that aid chemodetection and thus increase the attractiveness of the particles as food items. Much of the ingested plastic was, however, egested within a short time period (2-4 h) and the survival of adult Calanus females was not affected in an 11-day exposure. Negative effects of microplastics ingestion were thus limited. Our findings emphasize, however, that aging plays an important role in the transformation of microplastics at sea and ingestion by grazers, and should thus be considered in future microplastics ingestion studies and estimates of microplastics transfer into the marine food web. Copyright © 2017 Elsevier Ltd. All rights reserved.
Vezzulli, Luigi; Pezzati, Elisabetta; Huete-Stauffer, Carla; Pruzzo, Carla; Cerrano, Carlo
2013-01-01
Mass mortality events of benthic invertebrates in the Mediterranean Sea are becoming an increasing concern with catastrophic effects on the coastal marine environment. Sea surface temperature anomalies leading to physiological stress, starvation and microbial infections were identified as major factors triggering animal mortality. However the highest occurrence of mortality episodes in particular geographic areas and occasionally in low temperature deep environments suggest that other factors play a role as well. We conducted a comparative analysis of bacterial communities associated with the purple gorgonian Paramuricea clavata, one of the most affected species, collected at different geographic locations and depth, showing contrasting levels of anthropogenic disturbance and health status. Using massive parallel 16SrDNA gene pyrosequencing we showed that the bacterial community associated with healthy P. clavata in pristine locations was dominated by a single genus Endozoicomonas within the order Oceanospirillales which represented ∼90% of the overall bacterial community. P. clavata samples collected in human impacted areas and during disease events had higher bacterial diversity and abundance of disease-related bacteria, such as vibrios, than samples collected in pristine locations whilst showed a reduced dominance of Endozoicomonas spp. In contrast, bacterial symbionts exhibited remarkable stability in P. clavata collected both at euphotic and mesophotic depths in pristine locations suggesting that fluctuations in environmental parameters such as temperature have limited effect in structuring the bacterial holobiont. Interestingly the coral pathogen Vibrio coralliilyticus was not found on diseased corals collected during a deep mortality episode suggesting that neither temperature anomalies nor recognized microbial pathogens are solely sufficient to explain for the events. Overall our data suggest that anthropogenic influence may play a significant role in determining the coral health status by affecting the composition of the associated microbial community. Environmental stressful events and microbial infections may thus be superimposed to compromise immunity and trigger mortality outbreaks. PMID:23840768
NASA Astrophysics Data System (ADS)
Carbone, S.; Ferreira De Brito, J.; Cirino, G. G.; Rizzo, L. V.; Holanda, B. A.; Barbosa, H. M.; Ditas, F.; Pöhlker, C.; Chi, X.; Krüger, M. L.; Moran, D.; Saturno, J.; Andreae, M. O.; de Sá, S. S.; Liu, Y.; Martin, S. T.; Souza, R. A. F. D.; Wang, J.; Palm, B. B.; Jimenez, J. L.; Artaxo, P.
2015-12-01
The Amazon Basin during the wet season has one of the lowest aerosol concentrations worldwide, with air masses with negligible human impact covering thousands of kilometers of pristine forest. The natural environment is strongly modified near urbanized areas, in particular Manaus, a city of nearly two million people. This unique location provides the ideal laboratory to study isolated urban emissions as well the pristine environment by perturbing it in a relatively known fashion. The GoAmazon2014/5 experiment was designed with these questions in mind, combining remote sensing, in situ, and airborne measurements. This manuscript describes the measurements taken at the T0 site, upwind of Manaus, (the Amazonian Tall Tower Observatory, ATTO site), at the T2 site, near Manaus, frequently impacted by relatively fresh emissions from the city and at T3, 60 km downwind of Manaus. This work relates the aerosol dynamics of the mixture of anthropogenic emissions from Manaus and the biogenic air masses, and how it evolves from T2 to T3 under different atmospheric conditions. Focus is on the aerosol size distribution, supported by aerosol mass spectrometry and gas-phase composition, in particular at the T2 site. At T0, the aerosol number concentration has been observed to increase from an average of 380 cm-3 to 1750 cm-3 from the wet to the dry season. The mean geometric diameter increased as well, from 95 nm to 145 nm. Interestingly, at the T2 site no significant difference was observed in number concentration between wet and dry seasons (approximately 4300 cm-3) with an average diameter of 60 nm during the former and 97 nm in the latter. Such measurements provide a unique dataset to understand the aerosol life cycle and the impact of urban emissions in the heart of the Amazon Forest.
NASA Astrophysics Data System (ADS)
Dai, Si-Min; Tian, Han-Rui; Zhang, Mei-Lin; Xing, Zhou; Wang, Lu-Yao; Wang, Xin; Wang, Tan; Deng, Lin-Long; Xie, Su-Yuan; Huang, Rong-Bin; Zheng, Lan-Sun
2017-01-01
Discovery of organic-inorganic hybrid perovskites ignites the dream of next-generation solar cells fabricated by low-cost solution processing. To date, fullerene derivative [6,6]-phenyl-C61- butyric acid methyl ester (PC61BM), is the most prevalently used electron transport layer for high efficiency p-i-n planar heterojunction perovskite solar cells. Compared with PC61BM, pristine fullerenes, such as C60 and C70, have shown superiority of higher electron mobility and much lower costs. Due to the poor solubility and strong tendency to crystallize for pristine fullerenes in solution process, it is still a challenge to deposit compact and continuous film of pristine fullerenes for p-i-n type perovskite solar cells by solution processing. Herein, solution processed pristine fullerenes (C60 and C70) were used as electron transport layers to replace PC61BM in perovskite solar cells with high performance and enhanced stability. Power conversion efficiency of 14.04% was obtained by using mixture of C60 and C70 as electron transport layer, which is comparable to that of PC61BM based device (13.74%). We demonstrated that the strong tendency of pristine fullerenes to crystallize during solvent removal can be largely mitigated by mixing different kinds of pristine fullerenes. These findings implicate pristine fullerenes as promising electron transport layers for high performance perovskite solar cells.
Urban microbial ecology of a freshwater estuary of Lake Michigan.
Fisher, Jenny C; Newton, Ryan J; Dila, Deborah K; McLellan, Sandra L
Freshwater estuaries throughout the Great Lakes region receive stormwater runoff and riverine inputs from heavily urbanized population centers. While human and animal feces contained in this runoff are often the focus of source tracking investigations, non-fecal bacterial loads from soil, aerosols, urban infrastructure, and other sources are also transported to estuaries and lakes. We quantified and characterized this non-fecal urban microbial component using bacterial 16S rRNA gene sequences from sewage, stormwater, rivers, harbor/estuary, and the lake surrounding Milwaukee, WI, USA. Bacterial communities from each of these environments had a distinctive composition, but some community members were shared among environments. We used a statistical biomarker discovery tool to identify the components of the microbial community that were most strongly associated with stormwater and sewage to describe an "urban microbial signature," and measured the presence and relative abundance of these organisms in the rivers, estuary, and lake. This urban signature increased in magnitude in the estuary and harbor with increasing rainfall levels, and was more apparent in lake samples with closest proximity to the Milwaukee estuary. The dominant bacterial taxa in the urban signature were Acinetobacter, Aeromonas , and Pseudomonas , which are organisms associated with pipe infrastructure and soil and not typically found in pelagic freshwater environments. These taxa were highly abundant in stormwater and sewage, but sewage also contained a high abundance of Arcobacter and Trichococcus that appeared in lower abundance in stormwater outfalls and in trace amounts in aquatic environments. Urban signature organisms comprised 1.7% of estuary and harbor communities under baseflow conditions, 3.5% after rain, and >10% after a combined sewer overflow. With predicted increases in urbanization across the Great Lakes, further alteration of freshwater communities is likely to occur with potential long term impacts on the function of estuarine and nearshore ecosystems.
Potential scenarios for nanomaterial release and subsequent alteration in the environment.
Nowack, Bernd; Ranville, James F; Diamond, Stephen; Gallego-Urrea, Julian A; Metcalfe, Chris; Rose, Jerome; Horne, Nina; Koelmans, Albert A; Klaine, Stephen J
2012-01-01
The risks associated with exposure to engineered nanomaterials (ENM) will be determined in part by the processes that control their environmental fate and transformation. These processes act not only on ENM that might be released directly into the environment, but more importantly also on ENM in consumer products and those that have been released from the product. The environmental fate and transformation are likely to differ significantly for each of these cases. The ENM released from actual direct use or from nanomaterial-containing products are much more relevant for ecotoxicological studies and risk assessment than pristine ENM. Released ENM may have a greater or lesser environmental impact than the starting materials, depending on the transformation reactions and the material. Almost nothing is known about the environmental behavior and the effects of released and transformed ENM, although these are the materials that are actually present in the environment. Further research is needed to determine whether the release and transformation processes result in a similar or more diverse set of ENM and ultimately how this affects environmental behavior. This article addresses these questions, using four hypothetical case studies that cover a wide range of ENM, their direct use or product applications, and their likely fate in the environment. Furthermore, a more definitive classification scheme for ENM should be adopted that reflects their surface condition, which is a result of both industrial and environmental processes acting on the ENM. The authors conclude that it is not possible to assess the risks associated with the use of ENM by investigating only the pristine form of the ENM, without considering alterations and transformation processes. Copyright © 2011 SETAC.
NASA Astrophysics Data System (ADS)
Mason, O. U.; di Meo-Savoie, C. A.; Nakagawa, T.; van Nostrand, J. D.; Rosner, M.; Maruyama, A.; Zhou, J.; Fisk, M. R.; Giovannoni, S. J.
2008-12-01
Oceanic crust covers nearly 70% of the Earth's surface, of which, the upper, sediment layer is estimated to harbor substantial microbial biomass. Marine crust, however, extends several kilometers beyond this surficial layer, and includes the basalt and gabbro layers. The microbial diversity in basalts is well characterized, yet metabolic diversity is unknown. To date, the microflora associated with gabbros, including microbial and metabolic diversity has not been reported. In our analyses basaltic and gabbroic endoliths were analyzed using terminal restriction fragment length polymorphism, cloning and sequencing, and microarray analysis of functional genes. Our results suggest that despite nearly identical chemical compositions of basalt and gabbro the associated microflora did not overlap. Basalt samples harbor a surprising diversity of seemingly cosmopolitan microorganisms, some of which appear to be basalt specialists. Conversely, gabbros have a low diversity of endoliths, none of which appear to be specifically adapted to the gabbroic environment. Microarray analysis (GeoChip) was used to assay for functional gene diversity in basalts and gabbros. In basalt genes coding for previously unreported processes such as carbon fixation, methane-oxidation, methanogenesis, and nitrogen fixation were present, suggesting that basalts harbor previously unrecognized metabolic diversity. Similar processes were observed in gabbroic samples, yet metabolic inference from phylogenetic relationships of gabbroic endoliths with other microorganisms, suggests that hydrocarbon oxidation is the prevailing metabolism in this environment. Our analyses revealed that the basalt and gabbro layers harbor microorganisms with the genetic potential to significantly impact biogeochemical cycling in the lithosphere and overlying hydrosphere.
Wallisch, Stefanie; Gril, Tjasa; Dong, Xia; Welzl, Gerd; Bruns, Christian; Heath, Ester; Engel, Marion; Suhadolc, Marjetka; Schloter, Michael
2014-01-01
Alkane degrading microorganisms play an important role for the bioremediation of petrogenic contaminated environments. In this study, we investigated the effects of compost addition on the abundance and diversity of bacteria harboring the alkane monooxygenase gene (alkB) in an oil-contaminated soil originated from an industrial zone in Celje, Slovenia (Technosol). Soil without any amendments (control soil) and soil amended with two composts differing in their maturation stage and nutrient availability, were incubated under controlled conditions in a microcosm experiment and sampled after 0, 6, 12, and 36 weeks of incubation. As expected the addition of compost stimulated the degradation of alkanes in the investigated soil shortly after the addition. By using quantitative real-time PCR higher number of alkB genes were detected in soil samples amended with compost compared to the control soils. To get an insight into the composition of alkB harboring microbial communities, we performed next generation sequencing of amplicons of alkB gene fragment. Richness and diversity of alkB gene harboring prokaryotes was higher in soil mixed with compost compared to control soils with stronger effects of the less maturated, nutrient poor compost. The phylogenetic analysis of communities suggested that the addition of compost stimulated the abundance of alkB harboring Actinobacteria during the experiment independent from the maturation stage of the compost. AlkB harboring γ-proteobacteria like Shewanella or Hydrocarboniphaga as well as α-proteobacteria of the genus Agrobacterium responded also positively to the addition of compost to soil. The amendment of the less maturated, nutrient poor compost resulted in addition in a large increase of alkB harboring bacteria of the Cytophaga group (Microscilla) mainly at the early sampling time points. Our data indicates that compost amendments significantly change abundance and diversity pattern of alkB harboring microbes in Technosol and might be a useful agent to stimulate bioremediation of hydrocarbons in contaminated soils. PMID:24659987
Wallisch, Stefanie; Gril, Tjasa; Dong, Xia; Welzl, Gerd; Bruns, Christian; Heath, Ester; Engel, Marion; Suhadolc, Marjetka; Schloter, Michael
2014-01-01
Alkane degrading microorganisms play an important role for the bioremediation of petrogenic contaminated environments. In this study, we investigated the effects of compost addition on the abundance and diversity of bacteria harboring the alkane monooxygenase gene (alkB) in an oil-contaminated soil originated from an industrial zone in Celje, Slovenia (Technosol). Soil without any amendments (control soil) and soil amended with two composts differing in their maturation stage and nutrient availability, were incubated under controlled conditions in a microcosm experiment and sampled after 0, 6, 12, and 36 weeks of incubation. As expected the addition of compost stimulated the degradation of alkanes in the investigated soil shortly after the addition. By using quantitative real-time PCR higher number of alkB genes were detected in soil samples amended with compost compared to the control soils. To get an insight into the composition of alkB harboring microbial communities, we performed next generation sequencing of amplicons of alkB gene fragment. Richness and diversity of alkB gene harboring prokaryotes was higher in soil mixed with compost compared to control soils with stronger effects of the less maturated, nutrient poor compost. The phylogenetic analysis of communities suggested that the addition of compost stimulated the abundance of alkB harboring Actinobacteria during the experiment independent from the maturation stage of the compost. AlkB harboring γ-proteobacteria like Shewanella or Hydrocarboniphaga as well as α-proteobacteria of the genus Agrobacterium responded also positively to the addition of compost to soil. The amendment of the less maturated, nutrient poor compost resulted in addition in a large increase of alkB harboring bacteria of the Cytophaga group (Microscilla) mainly at the early sampling time points. Our data indicates that compost amendments significantly change abundance and diversity pattern of alkB harboring microbes in Technosol and might be a useful agent to stimulate bioremediation of hydrocarbons in contaminated soils.
Liang, Zhicong; Fan, Xiaofeng; Zheng, Weitao; Singh, David J
2017-05-24
Layered carbon is a likely anode material for Na-ion batteries (NIBs). Graphitic carbon has a low capacity of approximately 35 (mA h)/g due to the formation of NaC 64 . Using first-principles methods including van der Waals interactions, we analyze the adsorption of Na ions and clusters on graphene in the context of anodes. The interaction between Na ions and graphene is found to be weak. Small Na clusters are not stable on the surface of pristine graphene in the electrochemical environment of NIBs. However, we find that Na ions and clusters can be stored effectively on defected graphene that has double vacancies. In addition, the adsorption energy of small Na clusters near a double vacancy is found to decrease with increasing cluster size. With high concentrations of vacancies the capacity of Na on defective graphene is found to be as much as 10-30 times higher than that of graphitic carbon.
Modeling of Different Fiber Type and Content SiC/SiC Minicomposites Creep Behavior
NASA Technical Reports Server (NTRS)
Almansour, Amjad S.; Morscher, Gregory N.
2017-01-01
Silicon Carbide based Ceramic Matrix Composites (CMCs) are attractive materials for use in high-temperature applications in the aerospace and nuclear industries. However, creep damage mechanism in CMCs is the most dominant mechanism at elevated temperatures. Consequently, the tensile creep behavior of Hi-Nicalon, Hi-Nicalon Type S SiC fibers and Chemical vapor infiltrated Silicon Carbide matrix (CVI-SiC) were characterized and creep parameters were extracted from creep experiments. Some fiber creep tests were performed in inert environment at 1200 C on individual fibers. Creep behavior of different fiber content pristine and precracked Hi-Nicalon and Hi-Nicalon Type S reinforced minicomposites with BN interphases and CVI-SiC matrix were then modelled using the creep data found in this study and the literature and compared with creep experiments results for the pristine and precracked Hi-Nicalon and Hi-Nicalon Type S minicomposites. Finally, the effects of load-sharing and matrix cracking on CMC creep behavior will be discussed.
NASA Astrophysics Data System (ADS)
Los, J. H.; Kroes, J. M. H.; Albe, K.; Gordillo, R. M.; Katsnelson, M. I.; Fasolino, A.
2017-11-01
We present an extended Tersoff potential for boron nitride (BN-ExTeP) for application in large scale atomistic simulations. BN-ExTeP accurately describes the main low energy B, N, and BN structures and yields quantitatively correct trends in the bonding as a function of coordination. The proposed extension of the bond order, added to improve the dependence of bonding on the chemical environment, leads to an accurate description of point defects in hexagonal BN (h -BN) and cubic BN (c -BN). We have implemented this potential in the molecular dynamics LAMMPS code and used it to determine some basic properties of pristine 2D h -BN and the elastic properties of defective h -BN as a function of defect density at zero temperature. Our results show that there is a strong correlation between the size of the static corrugation induced by the defects and the weakening of the in-plane elastic moduli.
Bergknut, Magnus; Laudon, Hjalmar; Jansson, Stina; Larsson, Anna; Gocht, Tilman; Wiberg, Karin
2011-06-01
The mass-balance between diffuse atmospheric deposition of organic pollutants, amount of pollutants retained by the terrestrial environment, and levels of pollutants released to surface stream waters was studied in a pristine northern boreal catchment. This was done by comparing the input of atmospheric deposition of polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs) and PCBs with the amounts exported to surface waters. Two types of deposition samplers were used, equipped with a glass fibre thimble and an Amberlite sampler respectively. The measured fluxes showed clear seasonality, with most of the input and export occurring during winter and spring flood, respectively. The mass balance calculations indicates that the boreal landscape is an effective sink for PCDD/Fs and PCBs, as 96.0-99.9 % of received bulk deposition was retained, suggesting that organic pollutants will continue to impact stream water in the region for an extended period of time. Copyright © 2011 Elsevier Ltd. All rights reserved.
Further foraging for pristine nonmare rocks - Correlations between geochemistry and longitude
NASA Technical Reports Server (NTRS)
Warren, P. H.; Wasson, J. T.
1980-01-01
The most recent results from a project to find and describe pristine (that is, compositionally endogenous) nonmare rocks are reported. Sixteen nonmare samples are characterized petrographically and by composition, among them numerous key trace elements (siderophiles, incompatibles). Current knowledge about nonmare lunar rocks is surveyed, with emphasis placed on correlations between geochemistry and longitude. Several systematic differences between western ANT (that is, nonKREEPy, nonmare) rocks and the much more thoroughly studied eastern ANT rocks are noted. It is noted that western ANT rocks, whether pristine or nonpristine, tend to have higher Eu/Sm than their eastern counterparts. Pristine western ANT rocks, however, tend to have lower Sc/Sm and Ti/Sm than pristine eastern ANT rocks.
ERIC Educational Resources Information Center
Hsu, T. Ella; And Others
This study was designed to investigate the effects of the presence or absence of metacognitive skill tools available in hyperspace environments on field independent and field dependent learners. Learners were engaged in problem solving in an information-rich hyperspace based on a lesson on the attack on Pearl Harbor. Forty undergraduates were…
Gonzalez Carter, Daniel A.; Motskin, Michael; Pienaar, Ilse S.; Chen, Shu; Hu, Sheng; Ruenraroengsak, Pakatip; Ryan, Mary P.; Shaffer, Milo S. P.; Dexter, David T.
2016-01-01
Multi-walled carbon nanotubes (MWNTs) are increasingly being developed both as neuro-therapeutic drug delivery systems to the brain and as neural scaffolds to drive tissue regeneration across lesion sites. MWNTs with different degrees of acid oxidation may have different bioreactivities and propensities to aggregate in the extracellular environment, and both individualised and aggregated MWNTs may be expected to be found in the brain. Before practical application, it is vital to understand how both aggregates and individual MWNTs will interact with local phagocytic immune cells, the microglia, and ultimately to determine their biopersistence in the brain. The processing of extra- and intracellular MWNTs (both pristine and when acid oxidised) by microglia was characterised across multiple length scales by correlating a range of dynamic, quantitative and multi-scale techniques, including: UV-vis spectroscopy, light microscopy, focussed ion beam scanning electron microscopy and transmission electron microscopy. Dynamic, live cell imaging revealed the ability of microglia to break apart and internalise micron-sized extracellular agglomerates of acid oxidised MWNT, but not pristine MWNTs. The total amount of MWNTs internalised by, or strongly bound to, microglia was quantified as a function of time. Neither the significant uptake of oxidised MWNTs, nor the incomplete uptake of pristine MWNTs affected microglial viability, pro-inflammatory cytokine release or nitric oxide production. However, after 24 hrs exposure to pristine MWNTs, a significant increase in the production of reactive oxygen species was observed. Small aggregates and individualised oxidised MWNTs were present in the cytoplasm and vesicles, including within multilaminar bodies, after 72 hours. Some evidence of morphological damage to oxidised MWNT structure was observed including highly disordered graphitic structures, suggesting possible biodegradation. This work demonstrates the utility of dynamic, quantitative and multi-scale techniques in understanding the different cellular processing routes of functionalised nanomaterials. This correlative approach has wide implications for assessing the biopersistence of MWNT aggregates elsewhere in the body, in particular their interaction with macrophages in the lung. PMID:26298523
Pristine Inner Experience and Descriptive Experience Sampling: Implications for Psychology
Lapping-Carr, Leiszle R.; Heavey, Christopher L.
2017-01-01
Pristine inner experience is that which is directly present in awareness before it is distorted by attempts at observation or interpretation. Many psychological methods, including most introspective methods, attempt to measure some aspect of pristine inner experience (thoughts, feelings, mental imagery, sensations, etc.). We believe, however, that these methods produce unspecifiable combinations of pristine inner experience, beliefs about the self, beliefs about what inner experience should be like, inaccurate recollections, miscommunications, and other confounding influences. We argue that descriptive experience sampling (DES) can produce high fidelity descriptions of pristine inner experience. These descriptions are used to create idiographic profiles, carefully crafted, in-depth characterizations of the pristine inner experience of individuals. We believe these profiles, because they are built from moments apprehended via a method that confronts the challenges inherent in examining inner experience, are uniquely valuable in advancing the science of inner experience and psychology broadly. For example, DES observations raise important questions about the veracity of results gathered via questionnaires and other introspective methods, like casual introspection. DES findings also provide high fidelity phenomenological data that can be useful for those developing psychological theories, such as theories of emotional processing. Additionally, DES procedures may allow clinicians and clients to practice valuable skills, like bracketing presuppositions and attending to internal experiences. This paper will describe difficulties inherent in the study of pristine inner experience and discuss implications of high fidelity descriptions of pristine inner experience for psychological research, theory development, and clinical practice. PMID:29312047
A Survey of Terrestrial Approaches to the Challenge of Lunar Dust Containment
NASA Technical Reports Server (NTRS)
Aguilera, Tatiana; Perry, Jay L.
2009-01-01
Numerous technical challenges exist to successfully extend lunar surface exploration beyond the tantalizing first steps of Apollo. Among these is the challenge of lunar dust intrusion into the cabin environment. Addressing this challenge includes the design of barriers to intrusion as well as techniques for removing the dust from the cabin atmosphere. Opportunities exist for adapting approaches employed in dusty industrial operations and pristine manufacturing environments to cabin environmental quality maintenance applications. A survey of process technologies employed by the semiconductor, pharmaceutical, food processing, and mining industries offers insight into basic approaches that may be suitable for adaptation to lunar surface exploration applications.
Raman study of the Hg0.7Cr0.3Sr2CuO4+δ superconductors
NASA Astrophysics Data System (ADS)
Lee, S.-Y.; Chang, B.-Y.; Yang, I.-S.; Gwak, J.-H.; Kim, S.-J.; Choi, J.-H.; Lee, S.-I.; Yakhmi, J. V.; Mandal, J. B.; Bandyopadhyay, B.; Ghosh, B.
1997-08-01
The local environment of the apical oxygens (OA) in the Sr-substituted mercury-based superconductor Hg0.7Cr0.3Sr2CuO4+δ is investigated using Raman spectroscopy. Raman spectra from the Sr-substituted Hg-1201 samples show broad OA A1g double peaks at 553 and 583 cm-l, which are 10 - 20 cm-1 lower than the pristine Hg-1201. The existence of, and lower shift of, the double peaks in the Raman spectra of the Sr-substituted Hg-1201 superconductors indicate changes in the environment of OA in the Sr-substituted mercury-based superconductors.
Assessment of the U. S. Marine Transportation System : a report to congress
DOT National Transportation Integrated Search
1999-09-01
Discusses the collaborative effort to assess the adequacy of the Nation's marine : transportation system (including ports, waterways, harbor approach channels, and : their intermodal connections) to operate in a safe, efficient, secure, and : environ...
Re-construction layer effect of LiNi0.8Co0.15Mn0.05O2 with solvent evaporation process
NASA Astrophysics Data System (ADS)
Park, Kwangjin; Park, Jun-Ho; Hong, Suk-Gi; Choi, Byungjin; Heo, Sung; Seo, Seung-Woo; Min, Kyoungmin; Park, Jin-Hwan
2017-03-01
The solvent evaporation method on the structural changes and surface chemistry of the cathode and the effect of electrochemical performance of Li1.0Ni0.8Co0.15Mn0.05O2 (NCM) has been investigated. After dissolving of Li residuals using minimum content of solvent in order to minimize the damage of pristine material and the evaporation time, the solvent was evaporated without filtering and remaining powder was re-heated at 700 °C in oxygen environment. Two kinds of solvent, de-ionized water and diluted nitric acid, were used as a solvent. The almost 40% of Li residuals were removed using solvent evaporation method. The NCM sample after solvent evaporation process exhibited an increase in the initial capacity (214.3 mAh/g) compared to the pristine sample (207.4 mAh/g) at 0.1C because of enhancement of electric conductivity caused by decline of Li residuals. The capacity retention of NCM sample after solvent evaporation process (96.0% at the 50th cycle) was also improved compared to that of the pristine NCM sample (90.6% at the 50th cycle). The uniform Li residual layer after solvent treated and heat treatment acted like a coating layer, leading to enhance the cycle performance. The NCM sample using diluted nitric acid showed better performance than that using de-ionized water.
Honey bee gut microbial communities are robust to the fungicide Pristine® consumed in pollen
USDA-ARS?s Scientific Manuscript database
Honeybees that consume pollen with sublethal levels of the fungicide Pristine® can have reduced pollen digestion, lower ATP synthesis and in many ways resemble malnourished bees. Reduced nutrient acquisition in bees exposed to Pristine® might be because this fungicide affects the composition of gut ...
NASA Astrophysics Data System (ADS)
Cusnir, Ruslan; Christl, Marcus; Steinmann, Philipp; Bochud, François; Froidevaux, Pascal
2017-06-01
The interaction of trace environmental plutonium with dissolved natural organic matter (NOM) plays an important role on its mobility and bioavailability in freshwater environments. Here we explore the speciation and biogeochemical behavior of Pu in freshwaters of the karst system in the Swiss Jura Mountains. Chemical extraction and ultrafiltration methods were complemented by diffusive gradients in thin films technique (DGT) to measure the dissolved and bioavailable Pu fraction in water. Accelerator mass spectrometry (AMS) was used to accurately determine Pu in this pristine environment. Selective adsorption of Pu (III, IV) on silica gel showed that 88% of Pu in the mineral water is found in +V oxidation state, possibly in a highly soluble [PuO2+(CO3)n]m- form. Ultrafiltration experiments at 10 kDa yielded a similar fraction of colloid-bound Pu in the organic-rich and in mineral water (18-25%). We also found that the concentrations of Pu measured by DGT in mineral water are similar to the bulk concentration, suggesting that dissolved Pu is readily available for biouptake. Sequential elution (SE) of Pu from aquatic plants revealed important co-precipitation of potentially labile Pu (60-75%) with calcite fraction within outer compartment of the plants. Hence, we suggest that plutonium is fully available for biological uptake in both mineral and organic-rich karstic freshwaters.
Challenges in Liquid-Phase Exfoliation, Processing, and Assembly of Pristine Graphene.
Parviz, Dorsa; Irin, Fahmida; Shah, Smit A; Das, Sriya; Sweeney, Charles B; Green, Micah J
2016-10-01
Recent developments in the exfoliation, dispersion, and processing of pristine graphene (i.e., non-oxidized graphene) are described. General metrics are outlined that can be used to assess the quality and processability of various "graphene" products, as well as metrics that determine the potential for industrial scale-up. The pristine graphene production process is categorized from a chemical engineering point of view with three key steps: i) pretreatment, ii) exfoliation, and iii) separation. How pristine graphene colloidal stability is distinct from the exfoliation step and is dependent upon graphene interactions with solvents and dispersants are extensively reviewed. Finally, the challenges and opportunities of using pristine graphene as nanofillers in polymer composites, as well as as building blocks for macrostructure assemblies are summarized in the context of large-scale production. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Degraded visual environment image/video quality metrics
NASA Astrophysics Data System (ADS)
Baumgartner, Dustin D.; Brown, Jeremy B.; Jacobs, Eddie L.; Schachter, Bruce J.
2014-06-01
A number of image quality metrics (IQMs) and video quality metrics (VQMs) have been proposed in the literature for evaluating techniques and systems for mitigating degraded visual environments. Some require both pristine and corrupted imagery. Others require patterned target boards in the scene. None of these metrics relates well to the task of landing a helicopter in conditions such as a brownout dust cloud. We have developed and used a variety of IQMs and VQMs related to the pilot's ability to detect hazards in the scene and to maintain situational awareness. Some of these metrics can be made agnostic to sensor type. Not only are the metrics suitable for evaluating algorithm and sensor variation, they are also suitable for choosing the most cost effective solution to improve operating conditions in degraded visual environments.
Warren, Lesley A.; Kendra, Kathryn E.
2015-01-01
Microbial communities in engineered terrestrial haloalkaline environments have been poorly characterized relative to their natural counterparts and are geologically recent in formation, offering opportunities to explore microbial diversity and assembly in dynamic, geochemically comparable contexts. In this study, the microbial community structure and geochemical characteristics of three geographically dispersed bauxite residue environments along a remediation gradient were assessed and subsequently compared with other engineered and natural haloalkaline systems. In bauxite residues, bacterial communities were similar at the phylum level (dominated by Proteobacteria and Firmicutes) to those found in soda lakes, oil sands tailings, and nuclear wastes; however, they differed at lower taxonomic levels, with only 23% of operational taxonomic units (OTUs) shared with other haloalkaline environments. Although being less diverse than natural analogues, bauxite residue harbored substantial novel bacterial taxa, with 90% of OTUs nonmatchable to cultured representative sequences. Fungal communities were dominated by Ascomycota and Basidiomycota, consistent with previous studies of hypersaline environments, and also harbored substantial novel (73% of OTUs) taxa. In bauxite residues, community structure was clearly linked to geochemical and physical environmental parameters, with 84% of variation in bacterial and 73% of variation in fungal community structures explained by environmental parameters. The major driver of bacterial community structure (salinity) was consistent across natural and engineered environments; however, drivers differed for fungal community structure between natural (pH) and engineered (total alkalinity) environments. This study demonstrates that both engineered and natural terrestrial haloalkaline environments host substantial repositories of microbial diversity, which are strongly shaped by geochemical drivers. PMID:25979895
The Prevalence of the 22 deg Halo in Cirrus Clouds
NASA Technical Reports Server (NTRS)
Diedenhoven, vanBastiaan
2014-01-01
Halos at 22 deg from the sun attributed to randomly-orientated, pristine hexagonal crystals are frequently observed through ice clouds. These frequent sightings of halos formed by pristine crystals pose an apparent inconsistency with the dominance of distorted, nonpristine ice crystals indicated by in situ and remote sensing data. Furthermore, the 46 deg halo, which is associated with pristine hexagonal crystals as well, is observed far less frequently than the 22 deg halo. Considering that plausible mechanisms that could cause crystal distortion such as aggregation, sublimation, riming and collisions are stochastic processes that likely lead to distributions of crystals with varying distortion levels, here the presence of the 22 deg and 46 deg halo features in phase functions of mixtures of pristine and distorted hexagonal ice crystals is examined. We conclude that the 22 deg halo feature is generally present if the contribution by pristine crystals to the total scattering cross section is greater than only about 10% in the case of compact particles or columns, and greater than about 40% for plates. The 46 deg halo feature is present only if the mean distortion level is low and the contribution of pristine crystals to the total scattering cross section is above about 20%, 50% and 70%, in the case of compact crystals, plates and columns, respectively. These results indicate that frequent sightings of 22 deg halos are not inconsistent with the observed dominance of distorted, non-pristine ice crystals. Furthermore, the low mean distortion levels and large contributions by pristine crystals needed to produce the 461 halo features provide a potential explanation of the common sighting of the 22 deg halo without any detectable 46 deg halo.
Ruiz, J M; Romero, J
2003-12-01
The light-limitation hypothesis was tested to assess whether water turbidity had caused the decline of a Mediterranean Posidonia oceanica (L.) Delile meadow in an area affected by a harbor. The annual growth, photosynthesis and rhizome starch concentrations of seagrass were measured and related to changes in light availability and dissolved nutrient concentration along a gradient of meadow degradation from areas close to the harbor outwards. Environmental and plant variables were measured in three stations placed along this gradient and compared with a reference station at an undisturbed meadow. The light attenuation coefficient (k) increased toward the inner harbor area, mainly due to sediment resuspension. The shoot density and leaf productivity of P. oceanica shoots were much lower in disturbed stations of the inner harbor area than in the outer, less disturbed station and the reference meadow. However, daily leaf carbon gains, calculated from the photosynthetic rates at saturating irradiance (P(max)) and the daily period in which seagrass receives light higher than its saturating irradiance (H(sat)), suggested positive C-balance in all stations. This was partly explained by photo-acclimatization of seagrass to the reduced light availability at the disturbed harbor stations (inner and intermediate), as indicated by the lengthening of H(sat) and the decrease in saturating irradiance (I(sat)) and respiratory demands. Despite photo-acclimatization, disturbed harbor stations showed less positive C-balance, seen not only in their lower leaf growth and biomass but also in a decrease in rhizome carbohydrate reserves (starch). Our results suggest that light reduction account for the reduced seagrass productivity and abundance. However, meadow decline (in terms of shoot mortality) in the harbor area is well above that predicted from similar light environments of nearby meadows or simulated in shading experiments. Thus, there are other factors than light limitation involved in seagrass mortality, most probably through more complex interactions (e.g. nutrient-epiphytes-grazers, water quality--siltation).
NASA Astrophysics Data System (ADS)
Pucci, Stefano; Pantosti, Daniela; de Martini, Paolo Marco; Smedile, Alessandra; Munzi, Massimiliano; Cirelli, Enrico; Pentiricci, Massimo; Musso, Luisa
2010-05-01
Since ancient times, socio-economic strategies of some civilizations have led to undertake severe environmental modifications, so drastic as to require natural risk management. Societies responded to extreme natural disasters according to their socio-economic state: in some cases a society was resilient to perturbations and in others a society was so vulnerable to perturbations that it was unable to cope. Historical natural disasters left permanent marks on the cultural development of entire regions. These are recognized not only in the study of civilizations, urbanization, migrations etc., but also in the geology and geomorphology of an area. The sensitivity or vulnerability of landscapes and ecosystems to human activities were critical issues even during the Roman Empire. We analyze the relationships between human modification of the environment and natural events in the Roman city of Leptis Magna (UNESCO world heritage site), western Libya, located at the outlet of a major dry-land stream that served as a natural harbor. This magnificent town reached its maximum expansion during the Empire of Septimius Severus (193-211 A.D.) and started to decline during the late IV century. Historical and archaeological sources suggest that the harbor basin was abandoned due to its complete infill, possibly related to: i) violent flooding following the collapse of the local dam along the Wadi Lebda because of the large 365 A.D. earthquake (Crete, Greece); ii) lack of dam maintenance due to the decline of the settlement induced by severe damage after the 365 A.D. earthquake, or other local seismic sources; iii) immediate deposition caused by the tsunami wave of the 365 A.D. earthquake; iv) bad orientation and geometry of the harbor with respect to the local marine currents that were bringing debris inside. We present geological data, supported by geomorphological analysis and radiocarbon dating, with the aim to: 1) verify the hypotheses concerning the harbor abandonment; 2) reconstruct the main events of the close human-environment interaction; 3) check the cause-effect relationship between natural disasters and the settlement decline; 4) integrate the archaeological knowledge at Leptis Magna by independent chronological constraints.
NASA Astrophysics Data System (ADS)
Rivera, I.; Chadwick, B.; Rosen, G.; Wang, P. F.; Paquin, P.; Santore, R.; Ryan, A.
2015-12-01
Understanding the bioavailability of metals in the aquatic environment is important for defining appropriate regulatory constraints. A failure to recognize the importance of bioavailability factors on metal toxicity can result in criteria that are over- or under-protective. USEPA addresses the tendency of the national Water Quality Criterion (WQC) for regulation of copper in marine waters to underestimate the natural attenuation of copper toxicity in harbors by the application of site-specific Water Quality Standards (WQS). Which provides the level of protection intended by the WQC, and establishes realistic regulatory objectives. However, development of site-specific WQS involves a long-term effort, and does not account for temporal variation. The toxicity model seawater-Biotic Ligand Model (BLM) was developed and integrated with the existing Curvilinear Hydrodynamics in 3 Dimensions (CH3D) transport & fate model to create an efficient tool for development of site-specific WQS in harbors. The integrated model was demonstrated at a harbor-wide scale in San Diego Bay and Pearl Harbor, and accounted for the natural physical, chemical, biological and toxicological characteristics of the harbor to achieve more scientifically based compliance. In both harbors the spatial and temporal distributions of copper species, toxic effects, and Water Effect Ratio predicted by the integrated model are comparable to previous data. The model was further demonstrated in Shelter Island Yacht Basin (SIYB) marina in San Diego Bay. The integrated model agreed with toxicological and chemical approaches by indicating negligible bioavailability as well as no toxicity; but for a single event, even though an increasing gradient in Cu was observed both horizontally and vertically, with concentrations that reached levels well above current regulatory thresholds. These results support the incorporation by USEPA of the seawater-BLM in a full-strength seawater criterion.
Greig, Denise J.; Ip, Hon S.; Gulland, Frances M. D.; Miller, Woutrina A.; Conrad, Patricia A.; Field, Cara L.; Fleetwood, Michelle; Harvey, James T.; Jang, Spencer; Packham, Andrea; Wheeler, Elizabeth; Hall, Ailsa J.
2014-01-01
The infection status of harbor seals Phoca vitulina in central California, USA, was evaluated through broad surveillance for pathogens in stranded and wild-caught animals from 2001 to 2008, with most samples collected in 2007 and 2008. Stranded animals from Mendocino County to San Luis Obispo County were sampled at a rehabilitation facility: The Marine Mammal Center (TMMC, n = 175); wild-caught animals were sampled at 2 locations: San Francisco Bay (SF, n = 78) and Tomales Bay (TB, n = 97), that differed in degree of urbanization. Low prevalences of Salmonella, Campylobacter, Giardia, and Cryptosporidium were detected in the feces of stranded and wild-caught seals. Clostridium perfringens and Escherichia coli were more prevalent in the feces of stranded (58% [78 out of 135] and 76% [102 out of 135]) than wild-caught (42% [45 out of 106] and 66% [68 out of 106]) seals, whereas Vibrio spp. were 16 times more likely to be cultured from the feces of seals from SF than TB or TMMC (p < 0.005). Brucella DNA was detected in 3.4% of dead stranded harbor seals (2 out of 58). Type A influenza was isolated from feces of 1 out of 96 wild-caught seals. Exposure to Toxoplasma gondii, Sarcocystis neurona, and type A influenza was only detected in the wild-caught harbor seals (post-weaning age classes), whereas antibody titers to Leptospira spp. were detected in stranded and wild-caught seals. No stranded (n = 109) or wild-caught (n = 217) harbor seals had antibodies to phocine distemper virus, although a single low titer to canine distemper virus was detected. These results highlight the role of harbor seals as sentinel species for zoonotic and terrestrial pathogens in the marine environment.
Fox, Robert L; Fares, Ali; Wan, Y; Evensen, Carl I
2006-01-01
The influence of soil phosphorus (P) sources on P sorption characteristics of marine sediments was investigated for Pearl Harbor and off shore Molokai in Hawaii. Estuary sediments were sampled in seven locations; these represented different soils and on-shore activities. The soil samples included nine major soils that contributed sediment to the Harbor and coastal sediments near the island of Molokai. Sediment and soil samples were equilibrated for 6 days in 0.01 M CaCl(2) solution and synthetic seawater containing differing amounts of P. Phosphorus sorption curves were constructed. The equilibrated solution P, with no P added, ranged from 0.01 to 0.2 mg L(-1); P sorption by sediments at standard solution concentration 0.2 mg L(-1), ranged from 0 to 230 mg kg(-1). Sediment P sorption corresponded closely with soil sorption characteristics. Soils contributing sediments to the west reach of Pearl Harbor are highly weathered Oxisols with high standard P sorption values while those in the southeast of the Harbor were Vertisols and Mollisols which sorb little P. The influence of source materials on sediment P sorption was also observed for off-shore sediments near Molokai. Sediments serve as both source and sink for P in Pearl Harbor and in this role can be a stabilizing influence on P concentration in the water column. Phosphorus sorption curves in conjunction with water quality data can help to understand P dynamics between sediments and the water column and help evaluate concerns about P loading to a water body. For Pearl Harbor, solution P in equilibrium with sediments from the Lochs was 0.021 mg L(-1); a value unlikely to produce an algal bloom. (Measured total P in the water columns (mean) was 0.060.).
Kaplan, Ella; Sela, Noa; Doron-Faigenboim, Adi; Navon-Venezia, Shiri; Jurkevitch, Edouard; Cytryn, Eddie
2015-01-01
Municipal wastewater treatment facilities are considered to be “hotspots” for antibiotic resistance, since they conjoin high densities of environmental and fecal bacteria with selective pressure in the form of sub-therapeutic concentrations of antibiotics. Discharged effluents and biosolids from these facilities can disseminate antibiotic resistant genes to terrestrial and aquatic environments, potentially contributing to the increasing global trend in antibiotic resistance. This phenomenon is especially pertinent when resistance genes are associated with mobile genetic elements such as conjugative plasmids, which can be transferred between bacterial phyla. Fluoroquinolones are among the most abundant antibiotic compounds detected in wastewater treatment facilities, especially in biosolids, where due to their hydrophobic properties they accumulate to concentrations that may exceed 40 mg/L. Although fluoroquinolone resistance is traditionally associated with mutations in the gyrA/topoisomerase IV genes, there is increasing evidence of plasmid-mediated quinolone resistance, which is primarily encoded on qnr genes. In this study, we sequenced seven qnr-harboring plasmids from a diverse collection of Klebsiella strains, isolated from dewatered biosolids from a large wastewater treatment facility in Israel. One of the plasmids, termed pKPSH-11XL was a large (185.4 kbp), multi-drug resistance, IncF-type plasmid that harbored qnrB and 10 additional antibiotic resistance genes that conferred resistance to five different antibiotic families. It was highly similar to the pKPN3-like plasmid family that has been detected in multidrug resistant clinical Klebsiella isolates. In contrast, the six additional plasmids were much smaller (7–9 Kbp) and harbored a qnrS -type gene. These plasmids were highly similar to each other and closely resembled pGNB2, a plasmid isolated from a German wastewater treatment facility. Comparative genome analyses of pKPSH-11XL and other pKPN3-like plasmids concomitant to phylogenetic analysis of housekeeping genes from host Klebsiella strains, revealed that these plasmids are limited to a predominantly human-associated sub-clade of Klebsiella, suggesting that their host range is very narrow. Conversely, the pGNB2-like plasmids had a much broader host range and appeared to be associated with Klebsiella residing in natural environments. This study suggests that: (A) qnrB-harboring multidrug-resistant pKPN3-like plasmids can endure the rigorous wastewater treatment process and may therefore be disseminated to downstream environments; and (B) that small qnrS-harboring pGNB2-like plasmids are ubiquitous in wastewater treatment facilities and are most likely environmental in origin. PMID:26696974
Kaplan, Ella; Sela, Noa; Doron-Faigenboim, Adi; Navon-Venezia, Shiri; Jurkevitch, Edouard; Cytryn, Eddie
2015-01-01
Municipal wastewater treatment facilities are considered to be "hotspots" for antibiotic resistance, since they conjoin high densities of environmental and fecal bacteria with selective pressure in the form of sub-therapeutic concentrations of antibiotics. Discharged effluents and biosolids from these facilities can disseminate antibiotic resistant genes to terrestrial and aquatic environments, potentially contributing to the increasing global trend in antibiotic resistance. This phenomenon is especially pertinent when resistance genes are associated with mobile genetic elements such as conjugative plasmids, which can be transferred between bacterial phyla. Fluoroquinolones are among the most abundant antibiotic compounds detected in wastewater treatment facilities, especially in biosolids, where due to their hydrophobic properties they accumulate to concentrations that may exceed 40 mg/L. Although fluoroquinolone resistance is traditionally associated with mutations in the gyrA/topoisomerase IV genes, there is increasing evidence of plasmid-mediated quinolone resistance, which is primarily encoded on qnr genes. In this study, we sequenced seven qnr-harboring plasmids from a diverse collection of Klebsiella strains, isolated from dewatered biosolids from a large wastewater treatment facility in Israel. One of the plasmids, termed pKPSH-11XL was a large (185.4 kbp), multi-drug resistance, IncF-type plasmid that harbored qnrB and 10 additional antibiotic resistance genes that conferred resistance to five different antibiotic families. It was highly similar to the pKPN3-like plasmid family that has been detected in multidrug resistant clinical Klebsiella isolates. In contrast, the six additional plasmids were much smaller (7-9 Kbp) and harbored a qnrS -type gene. These plasmids were highly similar to each other and closely resembled pGNB2, a plasmid isolated from a German wastewater treatment facility. Comparative genome analyses of pKPSH-11XL and other pKPN3-like plasmids concomitant to phylogenetic analysis of housekeeping genes from host Klebsiella strains, revealed that these plasmids are limited to a predominantly human-associated sub-clade of Klebsiella, suggesting that their host range is very narrow. Conversely, the pGNB2-like plasmids had a much broader host range and appeared to be associated with Klebsiella residing in natural environments. This study suggests that: (A) qnrB-harboring multidrug-resistant pKPN3-like plasmids can endure the rigorous wastewater treatment process and may therefore be disseminated to downstream environments; and (B) that small qnrS-harboring pGNB2-like plasmids are ubiquitous in wastewater treatment facilities and are most likely environmental in origin.
NASA Astrophysics Data System (ADS)
Womble, J. N.; McNabb, R. W.; Gens, R.; Prakash, A.
2015-12-01
Some of the largest aggregations of harbor seals (Phoca vitulina richardii) in Alaska occur in tidewater glacier fjords where seals rest upon icebergs that are calved from tidewater glaciers into the marine environment. The distribution, amount, and size of floating ice in fjords are likely important factors influencing the spatial distribution and abundance of harbor seals; however, fine-scale characteristics of ice habitat that are used by seals have not been quantified using automated methods. We quantified the seasonal changes in ice habitat for harbor seals in Johns Hopkins Inlet, a tidewater glacier fjord in Glacier Bay National Park, Alaska, using aerial photography, object-based image analysis, and spatial models. Aerial photographic surveys (n = 53) were conducted of seals and ice during the whelping (June) and molting (August) seasons from 2007-2014. Surveys were flown along a grid of 12 transects and high-resolution digital photos were taken directly under the plane using a vertically aimed camera. Seal abundance and spatial distribution was consistently higher during June (range: 1,672-4,340) than August (range: 1,075-2,582) and corresponded to the spatial distribution and amount of ice. Preliminary analyses from 2007 suggest that the average percent of icebergs (ice ≥ than 1.6m2) and brash ice (ice < 1.6m2) per scene were greater in June (icebergs: 1.8% ± 1.6%; brash ice: 43.8% ± 38.9%) than August (icebergs: 0.2% ± 0.7%; brash ice; 15.8% ± 26.4%). Iceberg angularity (an index of iceberg shape) was also greater in June (1.7 ± 0.9) than August (0.9 ± 0.9). Potential factors that may influence the spatio-temporal variation in ice habitat for harbor seals in tidewater glacier fjords include frontal ablation rates of glaciers, fjord circulation, and local winds. Harbor seals exhibit high seasonal fidelity to tidewater glacier fjords, thus understanding the relationships between glacier dynamics and harbor seal distribution will be critical for understanding how future changes in tidewater glaciers may impact harbor seals.
Lightweight Exoatmospheric Projectile (LEAP) Test Program. Environment Assessment
1991-07-01
and Man-Made Environment Kwajalein Atoll is a coral reef containing approximately 100 islands surrounding the largest lagoon in the Nlorld. The Atoll is...entirely from the remains of marine organisms such as reef corals , coralline algae, foramnifera, and others. Soils are coarse, grain size, alkaline...Kwajalein Atoll include ocean reefs , lagoon reefs , lagoon floor and sand flats, harbors, piers, quarries, and sea grass beds. Several reef species are
Physics-Aware Informative Coverage Planning for Autonomous Vehicles
2014-06-01
environment and find the optimal path connecting fixed nodes, which is equivalent to solving the Traveling Salesman Problem (TSP). While TSP is an NP...intended for application to USV harbor patrolling, it is applicable to many different domains. The problem of traveling over an area and gathering...environment. I. INTRODUCTION There are many applications that need persistent monitor- ing of a given area, requiring repeated travel over the area to
Li, Huan; Qu, Jiapeng; Li, Tongtong; Wirth, Stephan; Zhang, Yanming; Zhao, Xinquan; Li, Xiangzhen
2018-06-03
The gut microbiota in mammals plays a key role in host metabolism and adaptation. However, relatively little is known regarding to how the animals adapts to extreme environments through regulating gut microbial diversity and function. Here, we investigated the diet, gut microbiota, short-chain fatty acid (SCFA) profiles, and cellulolytic activity from two common pika (Ochotona spp.) species in China, including Plateau pika (Ochotona curzoniae) from the Qinghai-Tibet Plateau and Daurian pika (Ochotona daurica) from the Inner Mongolia Grassland. Despite a partial diet overlap, Plateau pikas harbored lower diet diversity than Daurian pikas. Some bacteria (e.g., Prevotella and Ruminococcus) associated with fiber degradation were enriched in Plateau pikas. They harbored higher gut microbial diversity, total SCFA concentration, and cellulolytic activity than Daurian pikas. Interestingly, cellulolytic activity was positively correlated with the gut microbial diversity and SCFAs. Gut microbial communities and SCFA profiles were segregated structurally between host species. PICRUSt metagenome predictions demonstrated that microbial genes involved in carbohydrate metabolism and energy metabolism were overrepresented in the gut microbiota of Plateau pikas. Our results demonstrate that Plateau pikas harbor a stronger fermenting ability for the plant-based diet than Daurian pikas via gut microbial fermentation. The enhanced ability for utilization of plant-based diets in Plateau pikas may be partly a kind of microbiota adaptation for more energy requirements in cold and hypoxic high-altitude environments.
Comparative metagenomics reveals impact of contaminants on groundwater microbiomes
Hemme, Christopher L.; Tu, Qichao; Shi, Zhou; ...
2015-10-31
To understand patterns of geochemical cycling in pristine versus contaminated groundwater ecosystems, pristine shallow groundwater (FW301) and contaminated groundwater (FW106) samples from the Oak Ridge Integrated Field Research Center (OR-IFRC) were sequenced and compared to each other to determine phylogenetic and metabolic difference between the communities. Proteobacteria (e.g., Burkholderia, Pseudomonas) are the most abundant lineages in the pristine community, though a significant proportion ( >55%) of the community is composed of poorly characterized low abundance (individually <1%) lineages. The phylogenetic diversity of the pristine community contributed to a broader diversity of metabolic networks than the contaminated community. In addition, themore » pristine community encodes redundant and mostly complete geochemical cycles distributed over multiple lineages and appears capable of a wide range of metabolic activities. In contrast, many geochemical cycles in the contaminated community appear truncated or minimized due to decreased biodiversity and dominance by Rhodanobacter populations capable of surviving the combination of stresses at the site. In conclusion, these results indicate that the pristine site contains more robust and encodes more functional redundancy than the stressed community, which contributes to more efficient nutrient cycling and adaptability than the stressed community.« less
Investigation of novel material for effective photodegradation of bezafibrate in aqueous samples.
Regulska, Elżbieta; Karpińska, Joanna
2014-04-01
A novel composite with an enhanced photocatalytic activity was prepared and applied to study the removal of bezafibrate (BZF), a hypolypemic pharmaceutical, from an aqueous environment. For the enhancement of titanium dioxide photoactivity a fullerene derivative, 2-(ferrocenyl) fulleropyrrolidine (FcC60), was synthesized and applied. Obtained composite was found to show a higher catalytic activity than pristine TiO2. Therefore, high hopes are set in composites that are based on carbonaceous nanomaterials and TiO2 as a new efficient photocatalysts.
Young Forests and Farming Practices Can Benefit Wildlife.
Katie Greenberg; Kendrick Weeks; Gordon Warburton
2015-01-01
Thereâs a tendency to think of the hardwood forests of the South as pristine, undisturbed, and unchanging places that provide habitat for diverse animal and plant species. Indeed, having large blocks of mature forest is important for many wildlife species. The leafy tree canopy, tall trunks, hard mast, dead trees with holes, cool and shady micro-environment, and thick...
Igea, Javier; Bogarín, Diego; Papadopulos, Alexander S T; Savolainen, Vincent
2015-02-01
Speciation on islands, and particularly the divergence of species in situ, has long been debated. Here, we present one of the first, complete assessments of the geographic modes of speciation for the flora of a small oceanic island. Cocos Island (Costa Rica) is pristine; it is located 550 km off the Pacific coast of Central America. It harbors 189 native plant species, 33 of which are endemic. Using phylogenetic data from insular and mainland congeneric species, we show that all of the endemic species are derived from independent colonization events rather than in situ speciation. This is in sharp contrast to the results of a study carried out in a comparable system, Lord Howe Island (Australia), where as much as 8.2% of the plant species were the product of sympatric speciation. Differences in physiography and age between the islands may be responsible for the contrasting patterns of speciation observed. Importantly, comparing phylogenetic assessments of the modes of speciation with taxonomy-based measures shows that widely used island biogeography approaches overestimate rates of in situ speciation. © 2014 The Author(s). Evolution © 2014 The Society for the Study of Evolution.
Kepler, A.K.; Kepler, C.B.
1994-01-01
conclusion: Lushly wooded Caroline Atoll, with the majority of its 39 islets (399 ha of land) either in near-pristine condition or having recovered remarkably from past disturbance, is one of the least spoiled atolls in the Pacific. Uninhabited, it harbors plant ecosystems and breeding seabirds (Pt. II) of national and international importance. Its marine and terrestrial ecosystems are prime outdoor ecological laboratories for research on geological processes including ground water, sea level changes, the dynamics of motu formation, fish poisoning, and numerous facets of ecology including plant succession and Pisonia growth rates. Caroline boasts prime coral reefs thickly studded with Tridacna clams, substantial numbers of coconut crabs, breeding sites for green turtles, wintering grounds for shorebirds including the rare Bristle-thighed Curlew, ancient Tuamotuan marae, and a crystalline, unpolluted lagoon. The variety, abundance, and quality of its flora and fauna qualify it for status as an officially recognized international preserve (Pt. II, Sect. G). Efforts toward its conservation have thus far been unsuccessful: in 1992 it was leased to a private French businessman who is currently fishing the reefs for commercial profit, as well as disturbing seabird, turtle and coconut crab populations.
Kepler, C.B.; Kepler, A.K.; Ellis, D.H.
1994-01-01
conclusion: Lushly wooded Caroline Atoll, with the majority of its 39 islets (399 ha of land) either in near-pristine condition or having recovered remarkably from past disturbance, is one of the least spoiled atolls in the Pacific. Uninhabited, it harbors plant ecosystems and breeding seabirds (Pt. II) of national and international importance. Its marine and terrestrial ecosystems are prime outdoor ecological laboratories for research on geological processes including ground water, sea level changes, the dynamics of motu formation, fish poisoning, and numerous facets of ecology including plant succession and Pisonia growth rates. Caroline boasts prime coral reefs thickly studded with Tridacna clams, substantial numbers of coconut crabs, breeding sites for green turtles, wintering grounds for shorebirds including the rare Bristle-thighed Curlew, ancient Tuamotuan marae, and a crystalline, unpolluted lagoon. The variety, abundance, and quality of its flora and fauna qualify it for status as an officially recognized international preserve (Pt. II, Sect. G). Efforts toward its conservation have thus far been unsuccessful: in 1992 it was leased to a private French businessman who is currently fishing the reefs for commercial profit, as well as disturbing seabird, turtle and coconut crab populations.
Urban microbial ecology of a freshwater estuary of Lake Michigan
Fisher, Jenny C.; Newton, Ryan J.; Dila, Deborah K.
2015-01-01
Freshwater estuaries throughout the Great Lakes region receive stormwater runoff and riverine inputs from heavily urbanized population centers. While human and animal feces contained in this runoff are often the focus of source tracking investigations, non-fecal bacterial loads from soil, aerosols, urban infrastructure, and other sources are also transported to estuaries and lakes. We quantified and characterized this non-fecal urban microbial component using bacterial 16S rRNA gene sequences from sewage, stormwater, rivers, harbor/estuary, and the lake surrounding Milwaukee, WI, USA. Bacterial communities from each of these environments had a distinctive composition, but some community members were shared among environments. We used a statistical biomarker discovery tool to identify the components of the microbial community that were most strongly associated with stormwater and sewage to describe an “urban microbial signature,” and measured the presence and relative abundance of these organisms in the rivers, estuary, and lake. This urban signature increased in magnitude in the estuary and harbor with increasing rainfall levels, and was more apparent in lake samples with closest proximity to the Milwaukee estuary. The dominant bacterial taxa in the urban signature were Acinetobacter, Aeromonas, and Pseudomonas, which are organisms associated with pipe infrastructure and soil and not typically found in pelagic freshwater environments. These taxa were highly abundant in stormwater and sewage, but sewage also contained a high abundance of Arcobacter and Trichococcus that appeared in lower abundance in stormwater outfalls and in trace amounts in aquatic environments. Urban signature organisms comprised 1.7% of estuary and harbor communities under baseflow conditions, 3.5% after rain, and >10% after a combined sewer overflow. With predicted increases in urbanization across the Great Lakes, further alteration of freshwater communities is likely to occur with potential long term impacts on the function of estuarine and nearshore ecosystems. PMID:26866046
Li, Qiang; Zhao, Yinghe; Guo, Jiyuan; Zhou, Qionghua; Chen, Qian; Wang, Jinlan
2018-02-22
2D black phosphorus (BP) and transition metal chalcogenides (TMCs) have beneficial electronic, optical, and physical properties at the few-layer limit. However, irreversible degradation of exfoliated or chemical vapor deposition-grown ultrathin BP and TMCs like GaSe via oxidation under ambient conditions limits their applications. Herein, the on-surface growth of an oxidation-resistant 2D thin film of a metal coordination polymer is demonstrated by multiscale simulations. We show that the preparation of such heterostructures can be conducted in solution, in which pristine BP and GaSe present better stability than in an air environment. Our calculations reveal that the interaction between the polymer layer and 2D materials is dominated by van der Waals forces; thus, the electronic properties of pristine BP and GaSe are well preserved. Meanwhile, the isolation from oxygen and water can be achieved by monolayer polymers, due to the nature of their close-packed layers. Our facile strategy for enhancing the environmental stability of ultrathin materials is expected to accelerate efforts to implement 2D materials in electronic and optoelectronic applications.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wang, Jian; Krejci, Radovan; Giangrande, Scott
The nucleation of atmospheric vapours is an important source of new aerosol particles that can subsequently grow to form cloud condensation nuclei in the atmosphere. Most field studies of atmospheric aerosols over continents are influenced by atmospheric vapours of anthropogenic origin and, in consequence, aerosol processes in pristine, terrestrial environments remain poorly understood. The Amazon rainforest is one of the few continental regions where aerosol particles and their precursors can be studied under near-natural conditions, but the origin of small aerosol particles that grow into cloud condensation nuclei in the Amazon boundary layer remains unclear. Here we present aircraft- andmore » ground-based measurements under clean conditions during the wet season in the central Amazon basin. We find that high concentrations of small aerosol particles (with diameters of less than 50 nanometres) in the lower free troposphere are transported from the free troposphere into the boundary layer during precipitation events by strong convective downdrafts and weaker downward motions in the trailing stratiform region. Lastly, this rapid vertical transport can help to maintain the population of particles in the pristine Amazon boundary layer, and may therefore influence cloud properties and climate under natural conditions.« less
High-quality graphene flakes exfoliated on a flat hydrophobic polymer
NASA Astrophysics Data System (ADS)
Pedrinazzi, Paolo; Caridad, José M.; Mackenzie, David M. A.; Pizzocchero, Filippo; Gammelgaard, Lene; Jessen, Bjarke S.; Sordan, Roman; Booth, Timothy J.; Bøggild, Peter
2018-01-01
We show that graphene supported on a hydrophobic and flat polymer surface results in flakes with extremely low doping and strain as assessed by their Raman spectroscopic characteristics. We exemplify this technique by micromechanical exfoliation of graphene on flat poly(methylmethacrylate) layers and demonstrate Raman peak intensity ratios I(2D)/I(G) approaching 10, similar to pristine freestanding graphene. We verify that these features are not an artifact of optical interference effects occurring at the substrate: they are similarly observed when varying the substrate thickness and are maintained when the environment of the graphene flake is completely changed, by encapsulating preselected flakes between hexagonal boron nitride layers. The exfoliation of clean, pristine graphene layers directly on flat polymer substrates enables high performance, supported, and non-encapsulated graphene devices for flexible and transparent optoelectronic studies. We additionally show that the access to a clean and supported graphene source leads to high-quality van der Waals heterostructures and devices with reproducible carrier mobilities exceeding 50 000 cm2 V-1 s-1 at room temperature.
Wolansky, R.M.; Haeni, F.P.; Sylvester, R.E.
1983-01-01
A continuous marine seismic-reflection survey system was used to define the configuration of shallow sedimentary layers underlying the Charlotte Harbor and Venice areas, southwest Florida. Seismic profiling was conducted over a distance of about 57 miles of Charlotte Harbor, the Peace and Myakka Rivers, and the Intracoastal Waterway near Venice using a high resolution energy source capable of penetrating 200 feet of sediments with a resolution of 1 to 3 feet. Five stratigraphic units defined from the seismic records includes sediments to Holocene to early Miocene age. All seismic-profile records are presented, along with geologic sections constructed from the records. Seismic reflection amplitude, frequency, continuity, configuration, external form, and areal association were utilized to interpret facies and depositional environments of the stratigraphic units. The despositional framework of the units ranges from shallow shelf to prograded slope. The stratigraphic units are correlated with the surficial aquifer and intermediate artesian aquifers, and permeable zones of the aquifers are related to the seismic records. (USGS)
Reefs as cradles of evolution and sources of biodiversity in the Phanerozoic.
Kiessling, Wolfgang; Simpson, Carl; Foote, Michael
2010-01-08
Large-scale biodiversity gradients among environments and habitats are usually attributed to a complex array of ecological and evolutionary factors. We tested the evolutionary component of such gradients by compiling the environments of the geologically oldest occurrences of marine genera and using sampling standardization to assess if originations tended to be clustered in particular environments. Shallow, tropical environments and carbonate substrates all tend to have harbored high origination rates. Diversity within these environments tended to be preferentially generated in reefs, probably because of their habitat complexity. Reefs were also prolific at exporting diversity to other environments, which might be a consequence of low-diversity habitats being more susceptible to invasions.
75 FR 66309 - Vessel Traffic Service Lower Mississippi River
Federal Register 2010, 2011, 2012, 2013, 2014
2010-10-28
.... Indian Tribal Governments K. Energy Effects L. Technical Standards M. Environment I. Abbreviations AIS..., particularly in high water conditions. In one of the busiest industrial harbors in the world, vessels must... communications capability to interact with marine traffic and respond to developing situations. Through...
The Safe Harbor Mouse Retreat(™) is an innovative enrichment shelter that saves mice and money.
Froberg-Fejko, Karen M; Lecker, Jaime L
2013-10-01
Environmental enrichment can be defined as altering the living environment of captive animals in order to provide them with opportunities to express their natural behavioral repertoire. As important as offering an enriched environment is assuring lab animals are housed in the safest conditions possible. Cage flooding events are an unfortunate reality; however, technology is advancing to minimize these events. Bio-Serv, in collaboration with Allentown, Inc., has developed an innovative and economical shelter called the Safe Harbor Mouse Retreat (Fig. 1). This shelter offers a life-saving refuge for mice during these occasional, but devastating cage-flooding accidents. Mice will not be lost due to chilling or drowning caused by water exposure. Breeding mice can save their litters by moving their pups to the second level, and all mice can escape to the higher level where they can remain warm and dry until they are rescued. This clever shelter is not only life-saving for mice but offers several other significant benefits as well.
Chemical Sensing of Unexploded Ordnance with the Mobile Underwater Survey System (MUDSS)
NASA Technical Reports Server (NTRS)
Darrach, M. R.; Chutjian, A.
1995-01-01
The ability to sense explosives residues in the marine environment is a critical tool for identification and classification of underwater unexploded ordnance (UXO). Trace explosives signatures of TNT and DNT have been extracted from multiple sediment samples adjacent to unexploded undersea ordnance at Halifax Harbor, Canada. The ordnance was hurled into the harbor during a massive explosion fifty years earlier, in 1945 after World War II had ended. Laboratory sediment extractions were made using the solid-phase microextraction (SPME) method in seawater, and detection using the Reversal Electron Attachment Detection (READ) technique and, in the case of DNT, a commercial gas-chromatography/mass spectrometer (GC/MS). Results show that, after more than 50 years in the environment, ordnance which appeared to be physically intact gave good explosives signatures at the parts-per-billion level, whereas ordnance which had been cracked open during the explosion gave no signatures at the 10 parts-per-trillion sensitivity level. These measurements appear to provide the first reported data of explosives signatures from undersea UXOs.
Workshop on Pristine Highlands Rocks and the early History of the Moon
NASA Technical Reports Server (NTRS)
Longhi, J. (Editor); Ryder, G. (Editor)
1983-01-01
Oxide composition of the Moon, evidence for an initially totally molten Moon, geophysical contraints on lunar composition, random sampling of a layered intrusion, lunar highland rocks, early evolution of the Moon, mineralogy and petrology of the pristine rocks, relationship of the pristine nonmore rocks to the highlands soils and breccias, ferroan anorthositic norite, early lunar igneous history, compositional variation in ferroan anosthosites, a lunar magma ocean, deposits of lunar pristine rocks, lunar and planetary compositions and early fractionation in the solar nebula, Moon composition models, petrogenesis in a Moon with a chondritic refractory lithophile pattern, a terrestrial analog of lunar ilmenite bearing camulates, and the lunar magma ocean are summarized.
Temporal Dynamics of Bacterial and Fungal Colonization on Plastic Debris in the North Sea.
De Tender, Caroline; Devriese, Lisa I; Haegeman, Annelies; Maes, Sara; Vangeyte, Jürgen; Cattrijsse, André; Dawyndt, Peter; Ruttink, Tom
2017-07-05
Despite growing evidence that biofilm formation on plastic debris in the marine environment may be essential for its biodegradation, the underlying processes have yet to be fully understood. Thus, far, bacterial biofilm formation had only been studied after short-term exposure or on floating plastic, yet a prominent share of plastic litter accumulates on the seafloor. In this study, we explored the taxonomic composition of bacterial and fungal communities on polyethylene plastic sheets and dolly ropes during long-term exposure on the seafloor, both at a harbor and an offshore location in the Belgian part of the North Sea. We reconstructed the sequence of events during biofilm formation on plastic in the harbor environment and identified a core bacteriome and subsets of bacterial indicator species for early, intermediate, and late stages of biofilm formation. Additionally, by implementing ITS2 metabarcoding on plastic debris, we identified and characterized for the first time fungal genera on plastic debris. Surprisingly, none of the plastics exposed to offshore conditions displayed the typical signature of a late stage biofilm, suggesting that biofilm formation is severely hampered in the natural environment where most plastic debris accumulates.
Lönn, Mikael; Lind, Emma E.; Świeżak, Justyna; Smolarz, Katarzyna; Grahn, Mats
2016-01-01
Human-derived environmental pollutants and nutrients that reach the aquatic environment through sewage effluents, agricultural and industrial processes are constantly contributing to environmental changes that serve as drivers for adaptive responses and evolutionary changes in many taxa. In this study, we examined how two types of point sources of aquatic environmental pollution, harbors and sewage treatment plants, affect gene diversity and genetic differentiation in the blue mussel in the Baltic Sea area and off the Swedish west coast (Skagerrak). Reference sites (REF) were geographically paired with sites from sewage treatments plant (STP) and harbors (HAR) with a nested sampling scheme, and genetic differentiation was evaluated using a high-resolution marker amplified fragment length polymorphism (AFLP). This study showed that genetic composition in the Baltic Sea blue mussel was associated with exposure to sewage treatment plant effluents. In addition, mussel populations from harbors were genetically divergent, in contrast to the sewage treatment plant populations, suggesting that there is an effect of pollution from harbors but that the direction is divergent and site specific, while the pollution effect from sewage treatment plants on the genetic composition of blue mussel populations acts in the same direction in the investigated sites. PMID:27812424
Environmental Transmission of the Gut Symbiont Burkholderia to Phloem-Feeding Blissus insularis.
Xu, Yao; Buss, Eileen A; Boucias, Drion G
2016-01-01
The plant-phloem-feeding Blissus insularis possesses specialized midgut crypts, which harbor a dense population of the exocellular bacterial symbiont Burkholderia. Most individual B. insularis harbor a single Burkholderia ribotype in their midgut crypts; however, a diverse Burkholderia community exists within a host population. To understand the mechanism underlying the consistent occurrence of various Burkholderia in B. insularis and their specific association, we investigated potential gut symbiont transmission routes. PCR amplification detected a low titer of Burkholderia in adult reproductive tracts; however, fluorescence in situ hybridization assays failed to produce detectable signals in these tracts. Furthermore, no Burkholderia-specific PCR signals were detected in eggs and neonates, suggesting that it is unlikely that B. insularis prenatally transmits gut symbionts via ovarioles. In rearing experiments, most nymphs reared on St. Augustinegrass treated with cultured Burkholderia harbored the cultured Burkholderia strains. Burkholderia was detected in the untreated host grass of B. insularis, and most nymphs reared on untreated grass harbored a Burkholderia ribotype that was closely related to a plant-associated Burkholderia strain. These findings revealed that B. insularis neonates acquired Burkholderia primarily from the environment (i.e., plants and soils), even though the possibility of acquisition via egg surface cannot be excluded. In addition, our study explains how the diverse Burkholderia symbiont community in B. insularis populations can be maintained.
Barbers Point Harbor, Hawaii, Jetty Modification Study
2008-11-01
jetty lengths do not adversely impact the wave environment in the vicinity of the jetty. Production phase Figure 18 shows the normalized incident...objective of these current measurements is to show that the proposed jetty will not have any adverse impacts on the existing current patterns with no...with minimal construction costs and impact on the environment. ERDC/CHL TR-08-16 83 References Briggs, M. J., L. S. Lillycrop, G. S. Harkins
Insight into the Interaction between DNA Bases and Defective Graphenes: Covalent or Non-covalent
Xu, Zhenfeng; Meher, Biswa Ranjan; Eustache, Darnashley; Wang, Yixuan
2013-01-01
Although some metal clusters and molecules were found to more significantly bind to defective graphenes than to pristine graphenes, exhibiting chemisorptions on defective graphenes, the present investigation shows that the adsorption of DNA bases on mono- and di-vacant defective graphenes does not show much difference from that on pristine graphene, and is still dominantly driven by noncovalent interactions. In the present study the adsorptions of the nucleobases, adenine (A), cytosine (C), guanine, (G), and thymine (T) on pristine and defective graphenes, are fully optimized using a hybrid-meta GGA density functional theory (DFT), M06-2X/6-31G*, and the adsorption energies are then refined with both M06-2X and B97-D/6-311++G**. Graphene is modeled as nano-clusters of C72H24, C71H24, and C70H24 for pristine, mono- and divacant defective graphenes, respectively, supplemented by a few larger ones. The result shows that guanine has the maximum adsorption energy in all of the three adsorption systems; and the sequence of the adsorption strength is G>A>T>C on the pristine and di-vacant graphene and G>T>A>C on the mono-vacant graphene. In addition, the binding energies of the DNA bases with the pristine graphene are less than the corresponding ones with di-vacant defective graphene; however, they are greater than those of mono-vacant graphene with guanine and adenine, while it is dramatic that the binding energies of mono-vacant graphene with thymine and cytosine appear larger than those of pristine graphene. PMID:24215998
CCN and IN concentration measurements during the Antarctic Circumnavigation Expedition
NASA Astrophysics Data System (ADS)
Stratmann, F.; Henning, S.; Löffler, M.; Welti, A.; Hartmann, M.; Wernli, H.; Baccarini, A.; Schmale, J.
2017-12-01
Cloud condensation nuclei (CCN) and ice nuclei (IN) concentrations measured during the Antarctic Circumnavigation Expedition (ACE) within the Study of Preindustrial-like Aerosol-Climate Effects (SPACE) are presented. The measurements give a circumpolar transect through the Sub Antarctic Ocean, where existing measurements are scarce. ACE took place during the austral summer 2016/17 and included exploration of different environments from pristine open Ocean to Antarctic islands and the southernmost ports of the 3 surrounding continents. CCN concentrations are measured over the entire range of expected in-cloud supersaturations from 0.1 to 1% using a CCNc instrument from DMT. IN concentrations are determined from filter samples at water saturated conditions from -5°C to -25°C, covering common temperatures of mixed-phase cloud glaciation. The sensitivity of measured IN and CCN concentrations to meteorological parameters, activity of marine biology and location is assessed to gain insight into potential sources of CCN and IN. Back trajectory modelling is used to allocate regional variations to aerosol sources originating in the marine boundary layer or long-range transport. The gained datasets constrain CCN and IN concentrations in the marine boundary layer along the cruise track. The comprehensive set of parallel measured parameters during ACE allow to evaluate contributions of local ocean-surface sources versus long-range transport to Sub-Antarctic CCN and IN. The measurements can be used as input to climate models, e.g. pristine Sub Antarctic conditions can provide an approximation for a pre-industrial environment.
Imprint of the Past: Ecological History of New Bedford Harbor(AED)
Recently, the U.S. Environmenttal Protection Agency (EPA) adopted a new approach to study and manage environmental problems. In the past, the agency's emphasis was on particular pollutants and their effects on individual species in air, land, and water. But the environment is not...
Pristine nonmare rocks and the nature of the lunar crust
NASA Technical Reports Server (NTRS)
Warren, P. H.; Wasson, J. T.
1977-01-01
It is shown that the interdisciplinary study of the nonmare lunar rocks based on trace element, major element, and isotopic data plus petrographic evidence can succeed in amassing a large suite of demonstrably pristine rocks, and that the relative numbers of these rocks are not in accord with statistics amassed on soil fragments and glasses. The term 'pristine' is taken to mean rocks with primary compositions (albeit not necessarily textures) produced by lunar endogenous igneous processes. Melt rocks and crystalline matrix breccias produced by impact processes are excluded. A petrographic synonym for pristine would be 'unremelted, monomict'. It is found that anorthositic norites and noritic anorthosites were rare as primary nonmare rocks. Mechanical mixing appears to have been the dominant petrogenetic process on the highlands.
Combi, Tatiane; Martins, César C; Taniguchi, Satie; Leonel, Juliana; Lourenço, Rafael André; Montone, Rosalinda Carmela
2017-05-15
Temporal patterns, fluxes and inventories of polychlorinated biphenyls (PCBs) were assessed in nine sediment cores collected from selected areas of Admiralty Bay off the Antarctic Peninsula. Concentrations of total PCBs were low, but slightly higher in comparison to low-impacted, remote environments in the world, ranging from below the detection limit to 11.9ngg -1 in dry weight. PCB concentrations and inventories suggest a possible minor influence related to the nearby logistic activities, especially in the sediment core collected close to the Ferraz Station. Despite being the most remote and protected area on the planet, the Antarctic continent is no longer a pristine environment. Copyright © 2017 Elsevier Ltd. All rights reserved.
Coordinated Autonomy for Persistent Presence in Harbor and Riverine Environments
2007-09-30
estimators, and methods designed to deal with real-world problems such as video transmission noise; • OpenCV for basic computer vision functionality as...awareness and forward surveillance of Rocky’s intended path. Aerial video was transmitted to the UAV ground station, where an operator using GIS
Chemical Sensing of Unexploded Ordnance with the Mobile Underwater Survey System (MUDSS)
NASA Technical Reports Server (NTRS)
Chutjian, A.; Darrach, M.
1999-01-01
The ability to sense explosives residues in the marine environment is a critical tool for identification and classification of underwater unexploded ordnance (UXO). Trace explosives signatures of TNT and DNT have been extracted from mulitple sediment samples adjacent to unexploded undersea ordnance at Halifax Harbor, Canada.
USDA-ARS?s Scientific Manuscript database
The body of an animal encompasses a multitude of compositionally and functionally unique microbial environments, from the skin to the gastrointestinal system. Each of these systems harbor microbial communities that have adapted in order to cohabitate with their specific host resulting in a distinct...
USDA-ARS?s Scientific Manuscript database
Companion animals are a source of zoonotic infections and especially important considering the potential of companion animals to harbor antibiotic resistant pathogens. In this study, blaNDM positive Escherichia coli from companion animals, humans, and the environment from Mansoura, Egypt were charac...
There is a major effort to characterize the potential adverse effects of effluents released from sewage treatment plants in North America. At many locations pharmaceuticals, endocrine disruptors, and other chemicals of emerging concerns are present in the environment at concentra...
Insight into the interaction between DNA bases and defective graphenes: covalent or non-covalent.
Xu, Zhenfeng; Meher, Biswa Ranjan; Eustache, Darnashley; Wang, Yixuan
2014-02-01
Although some metal clusters and molecules were found to more significantly bind to defective graphenes than to pristine graphenes, exhibiting chemisorptions on defective graphenes, the present investigation shows that the adsorption of DNA bases on mono- and di-vacant defective graphenes does not show much difference from that on pristine graphene, and is still dominantly driven by noncovalent interactions. In the present study the adsorptions of the nucleobases, adenine (A), cytosine (C), guanine, (G), and thymine (T) on pristine and defective graphenes, are fully optimized using a hybrid-meta GGA density functional theory (DFT), M06-2X/6-31G*, and the adsorption energies are then refined with both M06-2X and B97-D/6-311++G**. Graphene is modeled as nano-clusters of C₇₂H₂₄, C₇₁H₂₄, and C₇₀H₂₄ for pristine, mono- and di-vacant defective graphenes, respectively, supplemented by a few larger ones. The result shows that guanine has the maximum adsorption energy in all of the three adsorption systems; and the sequence of the adsorption strength is G>A>T>C on the pristine and di-vacant graphene and G>T>A>C on the mono-vacant graphene. In addition, the binding energies of the DNA bases with the pristine graphene are less than the corresponding ones with di-vacant defective graphene; however, they are greater than those of mono-vacant graphene with guanine and adenine, while it is dramatic that the binding energies of mono-vacant graphene with thymine and cytosine appear larger than those of pristine graphene. Copyright © 2013 Elsevier Inc. All rights reserved.
Douglas, Thomas A; Walsh, Marianne E; McGrath, Christian J; Weiss, Charles A
2009-01-01
Explosives compounds, known toxins, are loaded to soils on military training ranges predominantly during explosives detonation events that likely fracture soil particles. This study was conducted to investigate the fate of explosives compounds in aqueous slurries containing fractured and pristine soil particles. Three soils were crushed with a piston to emulate detonation-induced fracturing. X-ray diffraction, energy-dispersive X-ray spectrometry, gas adsorption surface area measurements, and scanning electron microscopy were used to quantify and image pristine and fractured soil particles. Aqueous batches were prepared by spiking soils with solutions containing 2,4,6-trinitrotoluene (TNT), hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), octahydro 1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX), and 2,4-dinitrotoluene (2,4-DNT). Samples were collected over 92 d and the concentrations of the spiked explosives compounds and TNT transformation products 2-amino-4,6-dinitrotoluene (2ADNT) and 4-amino-2,6-dinitrotoluene (4ADNT) were measured. Our results suggest soil mineralogical and geochemical compositions were not changed during piston-induced fracturing but morphological differences were evident with fractured soils exhibiting more angular surfaces, more fine grained particles, and some microfracturing that is not visible in the pristine samples. TNT, 2,4-DNT, RDX, and HMX exhibited greater analyte loss over time in batch solutions containing fractured soil particles compared to their pristine counterparts. 2ADNT and 4ADNT exhibited greater concentrations in slurries containing pristine soils than in slurries containing fractured soils. Explosives compound transformation is greater in the presence of fractured soil particles than in the presence of pristine soil particles. Our results imply fractured soil particles promote explosive compound transformation and/or explosives compounds have a greater affinity for adsorption to fractured soil particle surfaces.
NASA Astrophysics Data System (ADS)
Rathore, Mahendra Singh; Vinod, Arun; Angalakurthi, Rambabu; Pathak, A. P.; Singh, Fouran; Thatikonda, Santhosh Kumar; Nelamarri, Srinivasa Rao
2017-11-01
High energy heavy ion irradiation-induced modification of high quality crystalline GeO2 thin films grown at different substrate temperatures ranging from 100 to 500 °C using pulsed laser deposition has been investigated. The pristine films were irradiated with 100 MeV Ag7+ ions at fixed fluence of 1 × 1013 ions/cm2. These pristine and irradiated films have been characterized using X-ray diffraction, atomic force microscopy, Raman spectroscopy, Fourier transform infrared and photoluminescence spectroscopy. The XRD and Raman results of pristine films confirm the formation of hexagonal structure of GeO2 films, whereas the irradiation eliminates all the peaks except major GeO2 peak of (101) plane. It is evident from the XRD results that crystallite size changes with substrate temperature and SHI irradiation. The surface morphology of films was studied by AFM. The functional group of pristine and irradiated films was investigated by IR transmission spectra. Pristine films exhibited strong photoluminescence around 342 and 470 nm due to oxygen defects and a red shift in the PL bands is observed after irradiation. Possible mechanism of tuning structural and optical properties of pristine as well as irradiated GeO2 films with substrate temperature and ion beam irradiation has been reported in detail.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Liu, Shuaishuai; Fifield, Leonard S.; Bowler, Nicola
Cross-linked polyethylene (XLPE) cable insulation material undergoes simultaneous, accelerated thermal and gamma-radiation aging to simulate the long-term aging environment within nuclear power plants (NPPs). A variety of materials characterization tests, including scanning electron microscopy, thermo-gravimetric analysis, differential scanning calorimetry, oxidation induction time, gel-fraction and dielectric properties measurement, are conducted on pristine and differently aged XLPE samples. A preliminary model of one possible aging mechanism of XLPE cable insulation material under gamma radiation at elevated temperature of 115 °C is suggested.
Esteban, N; Unsworth, R K F; Gourlay, J B Q; Hays, G C
2018-03-21
Our understanding of global seagrass ecosystems comes largely from regions characterized by human impacts with limited data from habitats defined as notionally pristine. Seagrass assessments also largely focus on shallow-water coastal habitats with comparatively few studies on offshore deep-water seagrasses. We satellite tracked green turtles (Chelonia mydas), which are known to forage on seagrasses, to a remote, pristine deep-water environment in the Western Indian Ocean, the Great Chagos Bank, which lies in the heart of one of the world's largest marine protected areas (MPAs). Subsequently we used in-situ SCUBA and baited video surveys to survey the day-time sites occupied by turtles and discovered extensive monospecific seagrass meadows of Thalassodendron ciliatum. At three sites that extended over 128 km, mean seagrass cover was 74% (mean range 67-88% across the 3 sites at depths to 29 m. The mean species richness of fish in seagrass meadows was 11 species per site (mean range 8-14 across the 3 sites). High fish abundance (e.g. Siganus sutor: mean MaxN.site -1 = 38.0, SD = 53.7, n = 5) and large predatory shark (Carcharhinus amblyrhynchos) (mean MaxN.site -1 = 1.5, SD = 0.4, n = 5) were recorded at all sites. Such observations of seagrass meadows with large top predators, are limited in the literature. Given that the Great Chagos Bank extends over approximately 12,500 km 2 and many other large deep submerged banks exist across the world's oceans, our results suggest that deep-water seagrass may be far more abundant than previously suspected. Copyright © 2018 The Author(s). Published by Elsevier Ltd.. All rights reserved.
Hadzi, George Yaw; Essumang, David Kofi; Ayoko, Godwin A
2018-06-16
Heavy metal contamination of selected rivers in Ghana was studied as part of a bigger project aimed at setting background standard for heavy metals in the Ghanaian environment. Water samples were collected from major mining and eight pristine areas. The samples were acid digested with aqua-regia and analyzed with ICP-MS for As, Cd, Hg, Zn, Cu, Mn, Fe, Cr, Al, V, Co, Ni, and Pb. The average concentrations (mg/L) from the pristine sites ranged from 0.002 ± 0.00(As) to 0.929 ± 0.06 (Fe) and 0.002 ± 0.00 (Pb) to 20.355 ± 5.60 (Fe) from the mining sites. With the exception of Al, Fe, and Mn, the metals level were found to be within the WHO and USEPA guideline limits. Hazard quotients (HQ) for ingestion and dermal contact for pristine and mining samples ranged from 3.00E-04 (Cu) to 0.84 (Cr) and 2.40E-06 (Cu) to 7.44 (As), respectively. The carcinogenic risk (CR) for ingestion and dermal contact ranged from 5.03E-06 to 1.71E-07 (Cr) and 4.22E-08 to 1.44E-09 (Cr), respectively. Arsenic showed a CR value higher than the acceptable limit (1.8E-02) from the mining sites which poses carcinogenic health threat. Multicriteria ranking suggests Birim river (EAM) as the most contaminated. The pattern recognition and multicriteria approach in characterizing the heavy metal contamination (for the first time in the case of Ghana) from the various sites will provide fresh insights into the risk assessment of heavy metals in contaminated surface waters.
Influence of paints formulations on nanoparticles release during their life cycle
NASA Astrophysics Data System (ADS)
Fiorentino, Brice; Golanski, Luana; Guiot, Arnaud; Damlencourt, Jean-François; Boutry, Delphine
2015-03-01
Pristine nanoparticles (NPs) may present a hazard to humans and the environment, and hence it is important to know to what extent NPs can be freely released from commercialized products in which they are added. The purpose of this study was to identify the parameters of the paint formulation containing SiO2 NPs of 19-nm diameter that could have an impact on the release induced by aging and abrasion. In order to simulate outdoor aging during the life cycle of the product, painted panels were exposed to accelerated weathering experiments in accordance with the norm EN ISO 16474-3:2013. The surface modification of these paints was characterized by scanning electron microscope coupled with energy dispersive spectrometry (SEM-EDS). These analyses showed that the acrylic copolymer binder has undergone a more significant chemical degradation compared with the styrene-acrylic copolymer. To simulate a mechanical aging, abrasion tests were conducted using a Taber Abraser, simulating critical scenarios of the abrasion standard. The particle size distributions and particle concentrations of the abraded particles were measured using an electric low-pressure impactor. After accelerated aging and abrasion tests, we observed a link between the paint degradations occurring with the release of pristine NPs and the embedded pristine NPs. Surface degradation of acrylic copolymer paints was more significant than that of the styrene-acrylic copolymer paints, and this induced a release of NPs 2.7 times higher. Other parameters like TiO2 addition as pigments induced a strong stability of paint against light and water, decreasing the total number of NPs released from paints from 30,000 to 1200 particles/cm3. These results revealed that formulations can be tuned to decrease the number of free NPs released and get a "safe-by-design" product.
NASA Astrophysics Data System (ADS)
Podzikowski, L. Y.; Capps, K. A.; Calhoun, A.
2014-12-01
Vernal pools are ephemeral wetlands in forested landscapes that fill with snowmelt, precipitation, and/or groundwater in the spring, and characteristically dry down through the summer months. Typically, vernal pool research has focused on the population and community ecology of pool-breeding organisms (amphibians and macroinvertebrates) conducted during their relatively short breeding season. Yet, little is known about the temporal variability of biogeochemical processes within and among vernal pools in urbanizing landscapes. In this study, we monitored physicochemical characteristics and nutrient dynamics in 22 vernal pools in central Maine post thaw in 2014. Four pristine pools were sampled weekly in five locations within the pool for ambient nutrient concentrations (SRP, NH4, NOx) and at three locations for physicochemical characteristics (DO, pH, temperature, conductivity). In the remaining 18 pools, we sampled one location for nutrients and three locations for physicochemical characteristics at least monthly to estimate the influence of increasing urbanization on the physical and chemical environment. Our data suggest most pools found in urbanizing areas have higher conductivity (developed sites ranging 18.52 - 1238 μS cm-1 compared to pristine between 14.08 - 58.4 μS cm-1). Previous work suggests forested pools exhibit dystrophic conditions with high coloration from DOC limiting primary production due to increased light attenuation in pools. However, both pristine and urban pools experienced spikes in DO (>100% saturation) throughout the day, suggesting that high productivity is not a reliable indicator of the effects of urbanization on vernal pools. We argue that continued monitoring of vernal pools along a gradient of urbanization could give insight into the role of ephemeral wetlands as potential biogeochemical hotspots and may also indicate how human development may alter biogeochemical cycling in ephemeral wetlands.
Pristine moon rocks - Apollo 17 anorthosites
NASA Technical Reports Server (NTRS)
Warren, P. H.; Jerde, E. A.; Kallemeyn, G. W.
1991-01-01
New chemical analyses and petrographic descriptions for 10 previously unanalyzed Apollo 17 rock samples are provided. Attention is focused on several that appear to be pristine. All samples were analyzed in INAA using a procedure based on that of Kallemeyn et al. (1989). One sample was found to be unambiguously pristine, and is the first pristine ferroan-anorthositic suite (FAS) sample from Apollo 17. It exhibits extremely low-mg(asterisk) mafic silicates, coupled with relatively sodic plagioclase. It has an unusually high augite/low-Ca pyroxene ratio and contains incompatible trace elements at levels unprecedentedly high compared to FAS anorthosites from the Apollo 14, 15, 16 sites. It is inferred that 74114.5, and Apollo 17 anorthosites in general, formed at a relatively late stage in the evolution of the primordial magmasphere.
Effects of LEO Environment on Tensile Properties of PEEK Films
NASA Astrophysics Data System (ADS)
Nakamura, Takashi; Nakamura, Hiroshi; Shimamura, Hiroyuki
2009-01-01
To clarify the effects of space environment on mechanical properties of polymer, exposure experiments were conducted utilizing the International Space Station Russian Service Module. Poly-ether-ether-ketone (PEEK) films under tensile stress were exposed to low Earth orbit (LEO) environment, and reference samples were irradiated with atomic oxygen (AO), electron beam (EB), and ultraviolet light (UV) in ground facilities. By comparing the results of flight and ground tests, the degradation behavior and the influential factors in LEO were investigated. The following results were obtained. (1) UV was found to be the harshest factor in LEO on tensile properties, since it decreased elongation to 15% of pristine sample after 46-months exposure. (2) AO in LEO eroded the specimen surface with a cone-like morphology and reduced the thickness; however, it had no significant effect on tensile properties. (3) EB irradiation in LEO had no measurable effects on the material properties.
Chen, Baowei; Yuan, Ke; Chen, Xin; Yang, Ying; Zhang, Tong; Wang, Yawei; Luan, Tiangang; Zou, Shichun; Li, Xiangdong
2016-07-05
Comprehensive profiles of antibiotic resistance genes (ARGs) and mobile genetic elements (MGEs) in a minimally impacted environment are essential to understanding the evolution and dissemination of modern antibiotic resistance. Chemical analyses of the samples collected from Tibet demonstrated that the region under investigation was almost devoid of anthropogenic antibiotics. The soils, animal wastes, and sediments were different from each other in terms of bacterial community structures, and in the typical profiles of ARGs and MGEs. Diverse ARGs that encoded resistance to common antibiotics (e.g., beta-lactams, fluoroquinolones, etc.) were found mainly via an efflux mechanism completely distinct from modern antibiotic resistome. In addition, a very small fraction of ARGs in the Tibetan environment were carried by MGEs, indicating the low potential of these ARGs to be transferred among bacteria. In comparison to the ARG profiles in relatively pristine Tibet, contemporary ARGs and MGEs in human-impacted environments have evolved substantially since the broad use of anthropogenic antibiotics.
CFD Modelling of Local Hemodynamics in Intracranial Aneurysms Harboring Arterial Branches.
Krylov, Vladimir; Grigoryeva, Elena; Dolotova, Daria; Blagosklonova, Evgenia; Gavrilov, Andrey
2017-01-01
The main cause of non-traumatic subarachnoid haemorrhage is an intracranial aneurysm's rupture. The choice of treatment approach is exceptionally difficult in cases of aneurysms with additional branches on the aneurysm's dome or neck. The impact of the arterial branches on local hemodynamics is still unclear and controversial question. At the same time, up-to-date methods of image processing and mathematical modeling provide a way to investigate the hemodynamic environment of aneurysms. The paper discusses hemodynamic aspects of aneurysms harboring arterial branch through the use of patient-specific 3D models and computational fluid dynamics (CFD) methods. The analysis showed that the presence of the arterial branches has a great influence on flow streamlines and wall shear stress, particularly for side wall aneurysm.
Environmental Transmission of the Gut Symbiont Burkholderia to Phloem-Feeding Blissus insularis
Xu, Yao; Buss, Eileen A.; Boucias, Drion G.
2016-01-01
The plant-phloem-feeding Blissus insularis possesses specialized midgut crypts, which harbor a dense population of the exocellular bacterial symbiont Burkholderia. Most individual B. insularis harbor a single Burkholderia ribotype in their midgut crypts; however, a diverse Burkholderia community exists within a host population. To understand the mechanism underlying the consistent occurrence of various Burkholderia in B. insularis and their specific association, we investigated potential gut symbiont transmission routes. PCR amplification detected a low titer of Burkholderia in adult reproductive tracts; however, fluorescence in situ hybridization assays failed to produce detectable signals in these tracts. Furthermore, no Burkholderia-specific PCR signals were detected in eggs and neonates, suggesting that it is unlikely that B. insularis prenatally transmits gut symbionts via ovarioles. In rearing experiments, most nymphs reared on St. Augustinegrass treated with cultured Burkholderia harbored the cultured Burkholderia strains. Burkholderia was detected in the untreated host grass of B. insularis, and most nymphs reared on untreated grass harbored a Burkholderia ribotype that was closely related to a plant-associated Burkholderia strain. These findings revealed that B. insularis neonates acquired Burkholderia primarily from the environment (i.e., plants and soils), even though the possibility of acquisition via egg surface cannot be excluded. In addition, our study explains how the diverse Burkholderia symbiont community in B. insularis populations can be maintained. PMID:27548682
Azimuth selection for sea level measurements using geodetic GPS receivers
NASA Astrophysics Data System (ADS)
Wang, Xiaolei; Zhang, Qin; Zhang, Shuangcheng
2018-03-01
Based on analysis of Global Positioning System (GPS) multipath signals recorded by a geodetic GPS receiver, GPS Reflectometry (GPS-R) has demonstrated unique advantages in relation to sea level monitoring. Founded on multipath reflectometry theory, sea level changes can be measured by GPS-R through spectral analysis of recorded signal-to-noise ratio data. However, prior to estimating multipath parameters, it is necessary to define azimuth and elevation angle mask to ensure the reflecting zones are on water. Here, a method is presented to address azimuth selection, a topic currently under active development in the field of GPS-R. Data from three test sites: the Kachemak Bay GPS site PBAY in Alaska (USA), Friday Harbor GPS site SC02 in the San Juan Islands (USA), and Brest Harbor GPS site BRST in Brest (France) are analyzed. These sites are located in different multipath environments, from a rural coastal area to a busy harbor, and they experience different tidal ranges. Estimates by the GPS tide gauges at azimuths selected by the presented method are compared with measurements from physical tide gauges and acceptable correspondence found for all three sites.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kennicutt, M.C. II; Sweet, S.T.; Fraser, W.R.
1991-03-01
In January to March 1989 water, organisms, and sediments within a 2-mile radius of Arthur Harbor were contaminated with an estimated 600,000 L of petroleum spilled by the Bahia Paraiso. All components of the ecosystem were contaminated to varying degrees during the spill, including birds, limpets, macroalgae, clams, bottom-feeding fish, and sediments. The high-energy environment, the relatively small volume of material released, and the volatility of the released product all contributed to limiting toxic effects in time and space. The most effective removal processes were evaporation, dilution, winds, and currents. Sedimentation, biological uptake, microbial oxidation, and photooxidation accounted for removalmore » of only a minor portion of the spill. One year after the spill several areas still exhibited contamination. Subtidal sediments and the more distant intertidal locations were devoid of detectable PAH contaminants whereas sediments near the docking facility at Palmer Station continued to reflect localized nonspill-related activities in the area. Arthur Harbor and adjacent areas continue to be chronically exposed to low-level petroleum contamination emanating from the Bahia Paraiso.« less
The Portland Harbor Superfund Site Sustainability Project: Introduction.
Fitzpatrick, Anne G; Apitz, Sabine E; Harrison, David; Ruffle, Betsy; Edwards, Deborah A
2018-01-01
This article introduces the Portland Harbor Superfund Site Sustainability Project (PHSP) special series in this issue. The Portland Harbor Superfund Site is one of the "mega-sediment sites" in the United States, comprising about 10 miles of the Lower Willamette River, running through the heart of Portland, Oregon. The primary aim of the PHSP was to conduct a comprehensive sustainability assessment, integrating environmental, economic, and social considerations of a selection of the remedial alternatives laid out by the US Environmental Protection Agency. A range of tools were developed for this project to quantitatively address environmental, economic, and social costs and benefits based upon diverse stakeholder values. In parallel, a probabilistic risk assessment was carried out to evaluate the risk assumptions at the core of the remedial investigation and feasibility study process. Integr Environ Assess Manag 2018;14:17-21. © 2017 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals, Inc. on behalf of Society of Environmental Toxicology & Chemistry (SETAC). © 2017 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals, Inc. on behalf of Society of Environmental Toxicology & Chemistry (SETAC).
Wang, Xiaoyan; Xu, Huanzhi; Zhou, Yongdong; Wu, Changwen; Kanchanopas-Barnette, Praparsiri
2015-12-30
Zhoushan Archipelago and the adjacent Xiangshan Harbor are important commercial, tourism, fishing, and mariculture areas. Considering the concern on the effects of anthropogenic activities on the environment, the level and source apportionment of polycyclic aromatic hydrocarbons (PAHs) in surface sediments were investigated. The sum of 16 PAH (∑16 PAH) concentrations in the Zhoushan Archipelago ranged from 3.67 to 31.30 ng g(-1) d.w., with a mean of 15.01 ± 1.21 ng g(-1) d.w., and that in Xiangshan Harbor varied from 11.58 to 481.44 ng g(-1) d.w., with a mean of 62.52 ± 32.85 ng g(-1) d.w. Diagnostic ratios and factor analysis were performed to identify PAH sources. Results show that PAHs have mixed origins (i.e., traffic-related sources, coal combustion, petrogenic sources, and biomass burning), with pyrolytic-related pollution as the dominant source. This study provided a baseline to promote environmental protection and pollution episode monitoring in the East China Sea. Copyright © 2015 Elsevier Ltd. All rights reserved.
Korine, Carmi; Pilosof, Shai; Gross, Amit; Morales-Malacara, Juan B; Krasnov, Boris R
2017-09-01
We examined the effects of sex, age, and reproductive state of the insectivorous bat Pipistrellus kuhlii on the abundance and prevalence of arthropod ectoparasites (Macronyssidae and Cimicidae) in habitats with either sewage-polluted or natural bodies of water, in the Negev Desert, Israel. We chose water pollution as an environmental factor because of the importance of water availability in desert environments, particularly for P. kuhlii, which needs to drink on a daily basis. We predicted that parasite infestation rates would be affected by both environment and demographic cohort of the host. We found that female bats in the polluted site harbored significantly more mites than female bats in the natural site and that juveniles in the polluted site harbored significantly more cimicid individuals than juveniles in the natural site. We further found that age and sex (host-related factors) affected ectoparasite prevalence and intensity (i.e., the abundance of parasites) in the polluted site. Our results may suggest that the interaction between host-related and environment-related factors affected parasite infestations, with females and young bats being more susceptible to ectoparasites when foraging over polluted water. This effect may be particularly important for bats that must drink or forage above water for other wildlife that depend on drinking water for survival.
Amazon boundary layer aerosol concentration sustained by vertical transport during rainfall
Wang, Jian; Krejci, Radovan; Giangrande, Scott; ...
2016-10-24
The nucleation of atmospheric vapours is an important source of new aerosol particles that can subsequently grow to form cloud condensation nuclei in the atmosphere. Most field studies of atmospheric aerosols over continents are influenced by atmospheric vapours of anthropogenic origin and, in consequence, aerosol processes in pristine, terrestrial environments remain poorly understood. The Amazon rainforest is one of the few continental regions where aerosol particles and their precursors can be studied under near-natural conditions, but the origin of small aerosol particles that grow into cloud condensation nuclei in the Amazon boundary layer remains unclear. Here we present aircraft- andmore » ground-based measurements under clean conditions during the wet season in the central Amazon basin. We find that high concentrations of small aerosol particles (with diameters of less than 50 nanometres) in the lower free troposphere are transported from the free troposphere into the boundary layer during precipitation events by strong convective downdrafts and weaker downward motions in the trailing stratiform region. Lastly, this rapid vertical transport can help to maintain the population of particles in the pristine Amazon boundary layer, and may therefore influence cloud properties and climate under natural conditions.« less
Amazon boundary layer aerosol concentration sustained by vertical transport during rainfall
NASA Astrophysics Data System (ADS)
Wang, Jian; Krejci, Radovan; Giangrande, Scott; Kuang, Chongai; Barbosa, Henrique M. J.; Brito, Joel; Carbone, Samara; Chi, Xuguang; Comstock, Jennifer; Ditas, Florian; Lavric, Jost; Manninen, Hanna E.; Mei, Fan; Moran-Zuloaga, Daniel; Pöhlker, Christopher; Pöhlker, Mira L.; Saturno, Jorge; Schmid, Beat; Souza, Rodrigo A. F.; Springston, Stephen R.; Tomlinson, Jason M.; Toto, Tami; Walter, David; Wimmer, Daniela; Smith, James N.; Kulmala, Markku; Machado, Luiz A. T.; Artaxo, Paulo; Andreae, Meinrat O.; Petäjä, Tuukka; Martin, Scot T.
2016-11-01
The nucleation of atmospheric vapours is an important source of new aerosol particles that can subsequently grow to form cloud condensation nuclei in the atmosphere. Most field studies of atmospheric aerosols over continents are influenced by atmospheric vapours of anthropogenic origin (for example, ref. 2) and, in consequence, aerosol processes in pristine, terrestrial environments remain poorly understood. The Amazon rainforest is one of the few continental regions where aerosol particles and their precursors can be studied under near-natural conditions, but the origin of small aerosol particles that grow into cloud condensation nuclei in the Amazon boundary layer remains unclear. Here we present aircraft- and ground-based measurements under clean conditions during the wet season in the central Amazon basin. We find that high concentrations of small aerosol particles (with diameters of less than 50 nanometres) in the lower free troposphere are transported from the free troposphere into the boundary layer during precipitation events by strong convective downdrafts and weaker downward motions in the trailing stratiform region. This rapid vertical transport can help to maintain the population of particles in the pristine Amazon boundary layer, and may therefore influence cloud properties and climate under natural conditions.
Amazon boundary layer aerosol concentration sustained by vertical transport during rainfall.
Wang, Jian; Krejci, Radovan; Giangrande, Scott; Kuang, Chongai; Barbosa, Henrique M J; Brito, Joel; Carbone, Samara; Chi, Xuguang; Comstock, Jennifer; Ditas, Florian; Lavric, Jost; Manninen, Hanna E; Mei, Fan; Moran-Zuloaga, Daniel; Pöhlker, Christopher; Pöhlker, Mira L; Saturno, Jorge; Schmid, Beat; Souza, Rodrigo A F; Springston, Stephen R; Tomlinson, Jason M; Toto, Tami; Walter, David; Wimmer, Daniela; Smith, James N; Kulmala, Markku; Machado, Luiz A T; Artaxo, Paulo; Andreae, Meinrat O; Petäjä, Tuukka; Martin, Scot T
2016-11-17
The nucleation of atmospheric vapours is an important source of new aerosol particles that can subsequently grow to form cloud condensation nuclei in the atmosphere. Most field studies of atmospheric aerosols over continents are influenced by atmospheric vapours of anthropogenic origin (for example, ref. 2) and, in consequence, aerosol processes in pristine, terrestrial environments remain poorly understood. The Amazon rainforest is one of the few continental regions where aerosol particles and their precursors can be studied under near-natural conditions, but the origin of small aerosol particles that grow into cloud condensation nuclei in the Amazon boundary layer remains unclear. Here we present aircraft- and ground-based measurements under clean conditions during the wet season in the central Amazon basin. We find that high concentrations of small aerosol particles (with diameters of less than 50 nanometres) in the lower free troposphere are transported from the free troposphere into the boundary layer during precipitation events by strong convective downdrafts and weaker downward motions in the trailing stratiform region. This rapid vertical transport can help to maintain the population of particles in the pristine Amazon boundary layer, and may therefore influence cloud properties and climate under natural conditions.
Santiago-Rodriguez, Tasha M; Toranzos, Gary A; Arce-Nazario, Javier A
2016-10-01
Urbanization affects the microbial loading into tropical streams, but its impact on water quality varies across watersheds. Rainfall in tropical environments also complicates microbial dynamics due to high seasonal and annual variations. Understanding the dynamics of fecal contamination in tropical surface waters may be further hindered by limitations from the utilization of traditional microbial indicators. We measured traditional (Enterococcus spp. and Escherichia coli), as well as alternate (enterophages and coliphages) indicators of fecal contamination in a tropical watershed in Puerto Rico during a 1-year period, and examined their relationship with rainfall events across an urbanization gradient. Enterococcus spp. and E. coli concentrations were 4 to 5 logs higher in non-urbanized or pristine sites when compared to enterophages and coliphages, suggesting that traditional fecal indicator bacteria may be natural inhabitants of pristine tropical waters. All of the tested indicators were positively correlated with rainfall and urbanization, except in the most urbanized sites, where rainfall may have had a dilution effect. The present study indicates that utilizing novel indicators of microbial water quality may improve the assessment of fecal contamination and pathogen risk for tropical watersheds.
Bubach, D F; Macchi, P J; Pérez Catán, S
2015-11-01
The elemental contents in salmonid muscle and liver tissues from different lakes around the world were investigated. Fish from pristine areas were compared with those fishes from impacted environments, both by volcanic and anthropogenic activities. Within the data, special attention was given to fishes from the Andean Patagonian lakes in two contexts: local and global. The local evaluation includes geological and limnological parameters and diet composition which were obtained through a data search from published works. The volcanic influence in Andean Patagonian lakes was mainly observed by an increase of cesium (Cs) and rubidium (Rb) concentrations in fishes, influenced by calcium (Ca) and potassium (K) water contents. Zinc (Zn), selenium (Se), iron (Fe), silver (Ag), and mercury (Hg) contents in fishes showed the effect of the geological substratum, and some limnological parameters. The diet composition was another factor which affects the elemental concentration in fishes. The analyzed data showed that the fishes from Andean Patagonian lakes had elemental content patterns corresponding to those of pristine regions with volcanic influence. Selenium and Ag contents from Andean Patagonian fishes were the highest reported.
NASA Astrophysics Data System (ADS)
Zeng, Huadong; Cheng, Xinlu; Wang, Wei
2018-03-01
The adsorption behaviors and properties of hydrazine (N2H4) molecules on pristine and Li-decorated graphene sheets were investigated by means of first-principles based on density functional theory. We systematically analyzed the optimal geometry, average binding energy, charge transfer, charge density difference and density of states of N2H4 molecules adsorbed on pristine and Li-decorated graphene sheets. It is found that the interaction between single N2H4 molecule and pristine graphene is weak physisorption with the low binding energy of -0.026 eV, suggesting that the pristine graphene sheet is insensitive to the presence of N2H4 molecule. However, it is markedly enhanced after lithium decoration with the high binding energy of -1.004 eV, verifying that the Li-decorated graphene sheet is significantly sensitive to detect N2H4 molecule. Meanwhile, the effects of the concentrations of N2H4 molecules on two different substrates were studied detailedly. For pristine graphene substrate, the average binding energy augments apparently with increasing the number of N2H4 molecules, which is mainly attributed to the van der Waals interactions and hydrogen bonds among N2H4 clusters. Li-decorated graphene sheet has still a strong affinity to N2H4 molecules despite the corresponding average binding energy emerges a contrary tendency. Overall, Li-decorated graphene sheet could be considered as a potential gas sensor in field of hydrazine molecules.
Simões, G A R; Xavier, M A S; Oliveira, D A; Menezes, E V; Magalhães, S S G; Gandra, J A C D; Xavier, A R E O
2016-06-17
Biotechnology industries that use recombinant DNA technology are potential sources for release of genetically modified organisms to the environment. Antibiotic-resistance marker genes are commonly used for recombinant bacteria selection. One example is the marker gene coding for β-lactamase (bla) in plasmids found in Escherichia coli K-12. The aim of this study was to provide an approach to develop a molecular method for genetic marker detection in E. coli K-12 harboring bla genes from an industrial wastewater treatment effluent pond (IWTEP). For the detection of bla and Achromobacter lyticus protease I (api) genes in samples from IWTEP, we employed multiplex polymerase chain reaction (PCR) using E. coli K-12 genetic marker detection primers, previously described in the literature, and primers designed in our laboratory. The microbiological screening method resulted in 22 bacterial colony-forming units isolated from three different IWTEP harvesting points. The multiplex PCR amplicons showed that five isolates were positive for the bla gene marker and negative for the E. coli K-12 and api genes. The 16S rRNA regions of positive microorganisms carrying the bla gene were genotyped by the MicroSeq®500 system. The bacteria found were Escherichia spp (3/5), Chromobacterium spp (1/5), and Aeromonas spp (1/5). None of the 22 isolated microorganisms presented the molecular pattern of E. coli K-12 harboring the bla gene. The presence of microorganisms positive for the bla gene and negative for E. coli K-12 harboring bla genes at IWTEP suggests that the ampicillin resistance found in the isolated bacteria could be from microorganisms other than the E. coli K-12 strain harboring plasmid.
Benitez, Kathleen; Masys, Daniel
2010-01-01
Objective Healthcare organizations must de-identify patient records before sharing data. Many organizations rely on the Safe Harbor Standard of the HIPAA Privacy Rule, which enumerates 18 identifiers that must be suppressed (eg, ages over 89). An alternative model in the Privacy Rule, known as the Statistical Standard, can facilitate the sharing of more detailed data, but is rarely applied because of a lack of published methodologies. The authors propose an intuitive approach to de-identifying patient demographics in accordance with the Statistical Standard. Design The authors conduct an analysis of the demographics of patient cohorts in five medical centers developed for the NIH-sponsored Electronic Medical Records and Genomics network, with respect to the US census. They report the re-identification risk of patient demographics disclosed according to the Safe Harbor policy and the relative risk rate for sharing such information via alternative policies. Measurements The re-identification risk of Safe Harbor demographics ranged from 0.01% to 0.19%. The findings show alternative de-identification models can be created with risks no greater than Safe Harbor. The authors illustrate that the disclosure of patient ages over the age of 89 is possible when other features are reduced in granularity. Limitations The de-identification approach described in this paper was evaluated with demographic data only and should be evaluated with other potential identifiers. Conclusion Alternative de-identification policies to the Safe Harbor model can be derived for patient demographics to enable the disclosure of values that were previously suppressed. The method is generalizable to any environment in which population statistics are available. PMID:21169618
Manheim, F.T.; Buchholtz ten Brink, Marilyn R.; Mecray, E.L.
1998-01-01
A comprehensive database of sediment chemistry and environmental parameters has been compiled for Boston Harbor and Massachusetts Bay. This work illustrates methodologies for rescuing and validating sediment data from heterogeneous historical sources. It greatly expands spatial and temporal data coverage of estuarine and coastal sediments. The database contains about 3500 samples containing inorganic chemical, organic, texture and other environmental data dating from 1955 to 1994. Cooperation with local and federal agencies as well as universities was essential in locating and screening documents for the database. More than 80% of references utilized came from sources with limited distribution (gray literature). Task sharing was facilitated by a comprehensive and clearly defined data dictionary for sediments. It also served as a data entry template and flat file format for data processing and as a basis for interpretation and graphical illustration. Standard QA/QC protocols are usually inapplicable to historical sediment data. In this work outliers and data quality problems were identified by batch screening techniques that also provide visualizations of data relationships and geochemical affinities. No data were excluded, but qualifying comments warn users of problem data. For Boston Harbor, the proportion of irreparable or seriously questioned data was remarkably small (<5%), although concentration values for metals and organic contaminants spanned 3 orders of magnitude for many elements or compounds. Data from the historical database provide alternatives to dated cores for measuring changes in surficial sediment contamination level with time. The data indicate that spatial inhomogeneity in harbor environments can be large with respect to sediment-hosted contaminants. Boston Inner Harbor surficial sediments showed decreases in concentrations of Cu, Hg, and Zn of 40 to 60% over a 17-year period.A comprehensive database of sediment chemistry and environmental parameters has been compiled for Boston Harbor and Massachusetts Bay. This work illustrates methodologies for rescuing and validating sediment data from heterogeneous historical sources. It greatly expands spatial and temporal data coverage of estuarine and coastal sediments. The database contains about 3500 samples containing inorganic chemical, organic, texture and other environmental data dating from 1995 to 1994. Cooperation with local and federal agencies as well as universities was essential in locating and screening documents for the database. More than 80% of references utilized came from sources with limited distribution (gray Task sharing was facilitated by a comprehensive and clearly defined data dictionary for sediments. It also served as a data entry template and flat file format for data processing and as a basis for interpretation and graphical illustration. Standard QA/QC protocols are usually inapplicable to historical sediment data. In this work outliers and data quality problems were identified by batch screening techniques that also provide visualizations of data relationships and geochemical affinities. No data were excluded, but qualifying comments warn users of problem data. For Boston Harbor, the proportion of irreparable or seriously questioned data was remarkably small (<5%), although concentration values for metals and organic contaminants spanned 3 orders of magnitude for many elements or compounds. Data from the historical database provide alternatives to dated cores for measuring changes in surficial sediment contamination level with time. The data indicate that spatial inhomogeneity in harbor environments can be large with respect to sediment-hosted contaminants. Boston Inner Harbor surficial sediments showed decreases in concentrations Cu, Hg, and Zn of 40 to 60% over a 17-year period.
2014-09-30
mammals face potentially dramatic changes in the environment, as well as continued disturbances of their ocean habitat from shipping, sonar, fisheries... Cheetahs of the deep sea: deep foraging sprints in short-finned pilot whales off Tenerife (Canary Islands). Journal of Animal Ecology 77:936-947.
75 FR 14493 - Safety Zone; Dive Platform, Pago Pago Harbor, American Samoa
Federal Register 2010, 2011, 2012, 2013, 2014
2010-03-26
... vessels for the planned diving operations in and around the CHEHALIS wreck. Background and Purpose On... performing operations in and around the CHEHALIS wreck. The safety zone is necessary to protect other vessels... CHEHALIS wreck to determine the wreck's potential pollution threat to the environment. In December 2009...
1981-03-01
Oncorhynchus nerka ) Smolts Subjected to Entrainment During Hydraulic Dredging in the Fräser River Estuary. Environment Canada, Fisheries and Marine...Technical Report Series No. PAC/T-76-16. 35 pages. Tutty, B.D. and J. McBride. 1976. Histopathology of Chum ( Oncorhynchus keta) and Sockeye
The Cabo Rojo Solar Salterns located on the southwest coast of Puerto Rico are composed of two main ecosystems (i.e., salt ponds and microbial mats). Even though these locations are characterized by high solar radiation (mean light intensity of 39 mol photons m-2d-1) they harbor ...
Perceived crowding at Boston Harbor Islands National Park Area
Megha Budruk; Robert E. Manning; William A. Valliere; Benjamin Wang
2002-01-01
The increasing popularity of outdoor recreation has led to concerns about the level and types of visitor use that can be accommodated in parks and related areas without causing unacceptable impacts to the recreation experience. Such impacts represent the social component of carrying capacity, and include perceived crowding. Crowding within recreation environments has...
USDA-ARS?s Scientific Manuscript database
: Conventional commercial broiler production involves the rearing of more than 20,000 broilers in a single confined space, atop bedding material such as pine shavings or rice hulls, for approximately 6.5 weeks. This environment is known for harboring pathogens and antibiotic resistant bacteria, but ...
Federal Register 2010, 2011, 2012, 2013, 2014
2010-04-23
... permit application included a proposed Programmatic Safe Harbor Agreement between ODFW and the Service... foster greater understanding of the Oregon chub and its place in the natural environment of the... Conservation Measures The Oregon Chub Working Group (Working Group) was formed in 1991. This group of Federal...
Metagenomic studies of the Red Sea.
Behzad, Hayedeh; Ibarra, Martin Augusto; Mineta, Katsuhiko; Gojobori, Takashi
2016-02-01
Metagenomics has significantly advanced the field of marine microbial ecology, revealing the vast diversity of previously unknown microbial life forms in different marine niches. The tremendous amount of data generated has enabled identification of a large number of microbial genes (metagenomes), their community interactions, adaptation mechanisms, and their potential applications in pharmaceutical and biotechnology-based industries. Comparative metagenomics reveals that microbial diversity is a function of the local environment, meaning that unique or unusual environments typically harbor novel microbial species with unique genes and metabolic pathways. The Red Sea has an abundance of unique characteristics; however, its microbiota is one of the least studied among marine environments. The Red Sea harbors approximately 25 hot anoxic brine pools, plus a vibrant coral reef ecosystem. Physiochemical studies describe the Red Sea as an oligotrophic environment that contains one of the warmest and saltiest waters in the world with year-round high UV radiations. These characteristics are believed to have shaped the evolution of microbial communities in the Red Sea. Over-representation of genes involved in DNA repair, high-intensity light responses, and osmoregulation were found in the Red Sea metagenomic databases suggesting acquisition of specific environmental adaptation by the Red Sea microbiota. The Red Sea brine pools harbor a diverse range of halophilic and thermophilic bacterial and archaeal communities, which are potential sources of enzymes for pharmaceutical and biotechnology-based application. Understanding the mechanisms of these adaptations and their function within the larger ecosystem could also prove useful in light of predicted global warming scenarios where global ocean temperatures are expected to rise by 1-3°C in the next few decades. In this review, we provide an overview of the published metagenomic studies that were conducted in the Red Sea, and the bio-prospecting potential of the Red Sea microbiota. Furthermore, we discuss the limitations of the previous studies and the need for generating a large and representative metagenomic database of the Red Sea to help establish a dynamic model of the Red Sea microbiota. Copyright © 2015 Elsevier B.V. All rights reserved.
Rathlavath, Srinu; Kohli, Vandita; Singh, Asem Sanjit; Lekshmi, Manjusha; Tripathi, Gayatri; Kumar, Sanath; Nayak, Binaya Bhusan
2017-12-18
Arcobacter butzleri is an emerging pathogen isolated from animals, food and the environment. In this study, 147 A. butzleri isolated from seafood and the coastal environment were tested for the presence of ten putative virulence genes (cadF, cj1349, ciaB, mviN, pldA, tlyA, hecA, hecB, irgA, iroE) and antimicrobial susceptibilities. Majority of the isolates harbored mviN (100%), cj1349 (97.2%), ciaB (95.9%), tlyA (91.8%), pldA (91.1%) and cadF (89.7%). Lower detection rates were observed for hecA (10.8%), hecB (19%), iroE (12.9%) and irgA (17.6%). Three A. butzleri isolates harbored all ten virulence genes. The occurrence of cj1349, ciaB, pldA, tlyA and hecA genes was significantly different (P≤0.05) among the isolates from different sources. All (100%) A. butzleri isolates were resistant to vancomycin, cephalothin, cefoxitin and sulphamethizole and susceptible to polymyxin-B, kanamycin, streptomycin, gentamicin, tetracycline and imipenem. Resistance to clinically important antibiotics such as cefotaxime (99.3%), ceftazidime (87.7%), nalidixic acid (70.7%), ampicillin (72.1%), ertapenem and amoxicillin-clavulanic acid (41.9%) was observed in A. butzleri from the environment. The isolates were highly susceptible to norfloxacin (97.9%) and colistin (97.2%), followed by ciprofloxacin (88.4%), meropenem (74.8%), chloramphenicol (72.7%) and erythromycin (69.3%). A. butzleri from different sources were not significantly different with respect to their antimicrobial susceptibility patterns. Multidrug resistance was observed in 66 (81.4%) isolates from fish, 29 (72.5%) isolates from shellfish and 17 (65.3%) isolates from coastal water. A. butzleri harboring virulence genes and resistance to multiple antibiotics found in seafood could be a potential health risk to seafood handlers and consumers. Continuous monitoring of seafood for potentially pathogenic A. butzleri is important to understand the evolution of antibiotic resistance in this emerging food pathogen and to determine the antimicrobial therapy regimen in the event of food-borne A. butzleri infections. Copyright © 2017 Elsevier B.V. All rights reserved.
Raihan, Mohammad Sharif; Liu, Jie; Huang, Juan; Guo, Huan; Pan, Qingchun; Yan, Jianbing
2016-08-01
Sixteen major QTLs regulating maize kernel traits were mapped in multiple environments and one of them, qKW - 9.2 , was restricted to 630 Kb, harboring 28 putative gene models. To elucidate the genetic basis of kernel traits, a quantitative trait locus (QTL) analysis was conducted in a maize recombinant inbred line population derived from a cross between two diverse parents Zheng58 and SK, evaluated across eight environments. Construction of a high-density linkage map was based on 13,703 single-nucleotide polymorphism markers, covering 1860.9 cM of the whole genome. In total, 18, 26, 23, and 19 QTLs for kernel length, width, thickness, and 100-kernel weight, respectively, were detected on the basis of a single-environment analysis, and each QTL explained 3.2-23.7 % of the phenotypic variance. Sixteen major QTLs, which could explain greater than 10 % of the phenotypic variation, were mapped in multiple environments, implying that kernel traits might be controlled by many minor and multiple major QTLs. The major QTL qKW-9.2 with physical confidence interval of 1.68 Mbp, affecting kernel width, was then selected for fine mapping using heterogeneous inbred families. At final, the location of the underlying gene was narrowed down to 630 Kb, harboring 28 putative candidate-gene models. This information will enhance molecular breeding for kernel traits and simultaneously assist the gene cloning underlying this QTL, helping to reveal the genetic basis of kernel development in maize.
Gelsleichter, James; Szabo, Nancy J
2013-07-01
The presence of human pharmaceuticals in sewage-impacted ecosystems is a growing concern that poses health risks to aquatic wildlife. Despite this, few studies have investigated the uptake of active pharmaceutical ingredients (APIs) in aquatic organisms. In this study, the uptake of 9 APIs from human drugs was examined and compared in neonate bull sharks (Carcharhinus leucas) residing in pristine (Myakka River) and wastewater-impacted (Caloosahatchee River) tributaries of Florida's Charlotte Harbor estuary. The synthetic estrogen used in human contraceptives (17α-ethynylestradiol) and 6 of the selective serotonin/norepinephrine reuptake inhibitors (citalopram, fluoxetine, fluvoxamine, paroxetine, sertraline, venlafaxine) used in human antidepressants were observed at detectable and, in some cases, quantifiable levels in plasma of Caloosahatchee River sharks. Comparatively, only venlafaxine was detected in the plasma of a single Myakka River shark at a level below the limit of quantitation. These results suggest that sharks residing in wastewater-impacted habitats accumulate APIs, a factor that may pose special risks to C. leucas since it is one of few shark species to regularly occupy freshwater systems. Further research is needed to determine if the low levels of API uptake observed in Caloosahatchee River bull sharks pose health risks to these animals. Copyright © 2013 Elsevier B.V. All rights reserved.
Willcox, Jon A L; Kim, Hyung J
2017-02-28
A molecular dynamics graphene oxide model is used to shed light on commonly overlooked features of graphene oxide membranes. The model features both perpendicular and parallel water flow across multiple sheets of pristine and/or oxidized graphene to simulate "brick-and-mortar" microstructures. Additionally, regions of pristine/oxidized graphene overlap that have thus far been overlooked in the literature are explored. Differences in orientational and hydrogen-bonding features between adjacent layers of water in this mixed region are found to be even more prominent than differences between pristine and oxidized channels. This region also shows lateral water flow in equilibrium simulations and orthogonal flow in non-equilibrium simulations significantly greater than those in the oxidized region, suggesting it may play a non-negligible role in the mechanism of water flow across graphene oxide membranes.
Weichselian Aeolian Geoheritage Top 20 of the Netherlands
NASA Astrophysics Data System (ADS)
van den Ancker, Hanneke; Jungerius, Pieter Dirk; Platform Aardkundige Waarden, members
2016-04-01
The Netherlands are known world-wide for its engineered landscapes, its deep polders and bulb fields. The deep polders, up to more than 5 meters below sea level, originated by reclaiming peat lakes and peat quarries made for fuel. Its bulb fields are situated on levelled permeable dunes on which the precise water management is possible that growing bulbs requires. The Waddensea and -islands are less widely known (except by German bathers), although they are a World Heritage. The Waddensea is a highly pristine tidal landscape that already occurs along the Dutch coast for over 10,000 years and an important Natura 2000 area. The Wadden islands have an interesting history of erosion and re-growth and old cultural landscapes that show the interaction of land use and small-scale differences in geology and geomorphology during different cultural periods. Therefore, it is time to change the international perception of foreign visitors to The Netherlands and add the high variety of its historical landscapes, partly pristine and partly old cultural landscapes, to its tourism qualities. The poster presents a Top 20 of a less spectacular but another internationally important Dutch landscape: the coversand sites of the Netherlands. The Top 20 is selected by Geoheritage NL's Platform Aardkundige Waarden. The coversands evolved during the Late Weichselian, when the Netherlands was not covered by land ice and for a long period of time was part of a polar desert. The coversand landscape with dunes of 0,5 m up to 15 metres is not spectacular, but very characteristic. The coversands comprise of more than half a kilometre broad and 40 kilometre long dunes, series of river dunes as well as isolated dunes. The coversands and related Holocene drift sands make up about a quarter of the Dutch landscape. Over a century ago more than half of this landscape still had its pristine topography. Now less than a few percent is remaining. Especially the few remaining heathlands on coversand are an important geoheritage because they have the most pristine geomorphology and soils. Other important coversand sites occur in neighbouring Germany and Belgium, which were part of the same Weichselian polar desert environment, but all countries in land ice covered Northern Europe have coversand occurrences. We propose to organize an international IAG - ProGEO- INQUA - meeting in spring 2017 to discuss the European coversand heritage and its management problems.
Contaminant transport in Massachusetts Bay
Butman, Bradford
Construction of a new treatment plant and outfall to clean up Boston Harbor is currently one of the world's largest public works projects, costing about $4 billion. There is concern about the long-term impact of contaminants on Massachusetts Bay and adjacent Gulf of Maine because these areas are used extensively for transportation, recreation, fishing, and tourism, as well as waste disposal. Public concern also focuses on Stellwagen Bank, located on the eastern side of Massachusetts Bay, which is an important habitat for endangered whales. Contaminants reach Massachusetts Bay not only from Boston Harbor, but from other coastal communities on the Gulf of Maine, as well as from the atmosphere. Knowledge of the pathways, mechanisms, and rates at which pollutants are transported throughout these coastal environments is needed to address a wide range of management questions.
Monitoring underwater explosions in the habitat of resident bottlenose dolphins.
dos Santos, Manuel E; Couchinho, Miguel N; Rita Luís, Ana; Gonçalves, Emanuel J
2010-12-01
Maintenance work on the harbor of Setúbal, in Portugal, required the removal of a 14-m deep rocky outcrop at the ship maneuver area, using about 35 kg of Gelamonite, a nitroglycerin-based high-explosive. This important harbor is located in the Sado estuary, a biologically rich environment and an important feeding area for a resident community of bottlenose dolphins. Using different safe range calculation models, a mitigation and monitoring plan was developed that minimized the risks of these underwater explosions for the dolphins. At our monitoring station, at 2 km from the demolition site, acoustic pressure levels in excess of 170 dB re 1 μPa (root-mean-square) were measured. Samples of dead fish collected at the site were indicative of shock trauma from the blasts.
Characterization of Legionella Species from Watersheds in British Columbia, Canada
Peabody, Michael A.; Caravas, Jason A.; Morrison, Shatavia S.; Mercante, Jeffrey W.; Prystajecky, Natalie A.; Raphael, Brian H.
2017-01-01
ABSTRACT Legionella spp. present in some human-made water systems can cause Legionnaires’ disease in susceptible individuals. Although legionellae have been isolated from the natural environment, variations in the organism’s abundance over time and its relationship to aquatic microbiota are poorly understood. Here, we investigated the presence and diversity of legionellae through 16S rRNA gene amplicon and metagenomic sequencing of DNA from isolates collected from seven sites in three watersheds with varied land uses over a period of 1 year. Legionella spp. were found in all watersheds and sampling sites, comprising up to 2.1% of the bacterial community composition. The relative abundance of Legionella tended to be higher in pristine sites than in sites affected by agricultural activity. The relative abundance levels of Amoebozoa, some of which are natural hosts of legionellae, were similarly higher in pristine sites. Compared to other bacterial genera detected, Legionella had both the highest richness and highest alpha diversity. Our findings indicate that a highly diverse population of legionellae may be found in a variety of natural aquatic sources. Further characterization of these diverse natural populations of Legionella will help inform prevention and control efforts aimed at reducing the risk of Legionella colonization of built environments, which could ultimately decrease the risk of human disease. IMPORTANCE Many species of Legionella can cause Legionnaires’ disease, a significant cause of bacterial pneumonia. Legionella in human-made water systems such as cooling towers and building plumbing systems are the primary sources of Legionnaires’ disease outbreaks. In this temporal study of natural aquatic environments, Legionella relative abundance was shown to vary in watersheds associated with different land uses. Analysis of the Legionella sequences detected at these sites revealed highly diverse populations that included potentially novel Legionella species. These findings have important implications for understanding the ecology of Legionella and control measures for this pathogen that are aimed at reducing human disease. PMID:28776042
Vukosav, Petra; Mlakar, Marina; Cukrov, Neven; Kwokal, Zeljko; Pižeta, Ivanka; Pavlus, Natalija; Spoljarić, Ivanka; Vurnek, Maja; Brozinčević, Andrijana; Omanović, Dario
2014-03-01
An evaluation of the quality status of the pristine karst, tufa depositing aquatic environment of the Plitvice Lakes National Park based on the analysis of heavy (ecotoxic) metals was examined for the first time. Analyses of trace metals in water, sediment and fish (Salmo trutta, Oncorhynchus mykiss, Squalius cephalus) samples were conducted either by stripping voltammetry (Zn, Cd, Pb and Cu) or cold vapour atomic absorption spectrometry (Hg). The concentration of dissolved trace metals in water was very low revealing a pristine aquatic environment (averages were, in ng/L: 258 (Zn), 10.9 (Cd), 11.7 (Pb), 115 (Cu) and 1.22 (Hg)). Slightly enhanced concentrations of Cd (up to 50 ng/L) and Zn (up to 900 ng/L) were found in two main water springs and are considered as of natural origin. Observed downstream decrease in concentration of Cd, Zn and Cu in both water and sediments is a consequence of the self-purification process governed by the formation and settling of authigenic calcite. Anthropogenic pressure was spotted only in the Kozjak Lake: Hg concentrations in sediments were found to be up to four times higher than the baseline value, while at two locations, Pb concentrations exceeded even a probable effect concentration. The increase of Hg and Pb was not reflected on their levels in the fish tissues; however, significant correlations were found between Cd level in fish tissues (liver and muscle) and in the water/sediment compartments, while only partial correlations were estimated for Zn and Cu. A high discrepancy between values of potentially bioavailable metal fraction estimated by different modelling programs/models raised the question about the usefulness of these data as a parameter in understanding/relating the metal uptake and their levels in aquatic organism. The aquatic environment of the Plitvice Lakes National Park is characterized, in general, as a clean ecosystem.
2004-06-01
Rectified Infrared Aerial Photos Image112-4 flown on 9/9/01. F22 Appendix F Shoreline and Bathymetry Data Map registration and digitizing...Division 108( WW2 ), 163-179. Soulsby, R. L., and Whitehouse, R. J. S. W. (1997). “Threshold of sediment motion in coastal environments,” Proceeings
Federal Register 2010, 2011, 2012, 2013, 2014
2013-05-20
... vicinity of Nome is not adequate to accommodate the need for an efficient and safe harbor appropriate to... Transportation is working with the U. S. Army Corps of Engineers in investigating the need for expanding the... encounter the haphazard navigation scenario that presently exists in a challenging maritime environment...
The role of porosity in thermal inertia variations on basaltic lavas
NASA Technical Reports Server (NTRS)
Zimbelman, James R.
1986-01-01
Thermal inertia, defined as the square root of the product of thermal conductivity, density, and specific heat, has been noted to vary in inverse proportion to porosity in Hawaiian basalts. It is presently suggested that porosities of the order of more than 80 percent are required if the low thermal inertias observed in Martian shield volcanoes are the result of pristine lava flow surface properties. An aeolian origin is held to be most likely in view of thermal measurements on Mars; the volcanic surfaces in question are anticipated to have a short lifetime in their environment.
NASA Astrophysics Data System (ADS)
Elmaleh, A.; Galy, A.; Allard, T.; Dairon, R.; Day, J. A.; Michel, F.; Marriner, N.; Morhange, C.; Couffignal, F.
2012-04-01
The Antique and Byzantine sediments of the northern harbor of Tyre (Lebanon) store high amounts of metals and metalloids as the result of a millennial anthropogenic contamination as well as of efficient trapping and immobilization processes. Geochemical and mineralogical analyses reveal the contrasted patterns for the accumulation of trace metal(loid)s in the sedimentary sequence recovered by coring the inner part, now emerged, of the ancient harbor. Lead, Sn, Cu and Ag concentrations can be as high as 3000, 150, 1000, and 1.2 μg/g, respectively. Enrichment factors were calculated with respect to (1) Th and (2) the chemistry of the substratum and appear to be driven by anthropogenic inputs. Indeed, a drastic change in both excess concentrations and concentration ratios is observed through Roman and Byzantine times, pointing to major intensification of the trade and use of metals in Tyre, coherent with historical data. Good preservation of the archeological signal, despite (1) sediment disturbances that have caused age depth inversions, and (2) the large time lapse since the time of deposition of anthropogenic trace metal(loid)s is probably due to the reducing character of the sediments. Tyre's sedimentary sequence provides an interesting analog for modern carbonate-rich harbor environments, in which a millenary accumulation of trace metal(loid)s has been overall well preserved and suggests a restricted mobility of anthropogenic contamination for a period of time in excess of 1500 years.
Code of Federal Regulations, 2010 CFR
2010-07-01
..., and port and harbor areas, including vessels and harbor craft therein. 125.15 Section 125.15....15 Access to waterfront facilities, and port and harbor areas, including vessels and harbor craft....09 to those waterfront facilities, and port and harbor areas, including vessels and harbor craft...
Macroscopic crack formation and extension in pristine and artificially aged PBX 9501
DOE Office of Scientific and Technical Information (OSTI.GOV)
Liu, Cheng; Thompson, Darla G
2010-01-01
A technique has been developed to quantitatively describe macroscopic cracks, both their location and extent, in heterogeneous high explosive and mock materials. By combining such a technique with the deformation field measurement using digital image correlation (DIC), we conduct observation and measurement of the initiation, extension, and coalescence of internal cracks in the compression of Brazilian disk made of pristine and artificially aged PBX 9501 hjgh explosives. Our results conclude quantitatively that aged PBX 9501 is not only weaker but also much more brittle than the pristine one, thus is more susceptible to macroscopic cracking.
NASA Astrophysics Data System (ADS)
Sharma, R.; Raghuvanshi, S.; Satalkar, M.; Kane, S. N.; Tatarchuk, T. R.; Mazaleyrat, F.
2018-05-01
NiFe2O4, Ni0.5Zn0.5Fe2O4 samples were synthesized using sol-gel auto combustion method, and irradiated by using 120 MeV 28Si9+ ion with ion fluence of 1×1012 ions/cm2. Characterization of pristine, irradiated samples were done using X-Ray Diffraction (XRD), Field Emission Scanning Microscopy (FE-SEM), Energy Dispersive X-ray Analysis (EDAX) and Vibrating Sample Magnetometer (VSM). XRD validates the single phase nature of pristine, irradiated Ni- Zn nano ferrite except for Ni ferrite (pristine, irradiated) where secondary phases of α-Fe2O3 and Ni is observed. FE- SEM images of pristine Ni, Ni-Zn ferrite show inhomogeneous nano-range particle size distribution. Presence of diamagnetic ion (Zn2+) in NiFe2O4 increases oxygen positional parameter (u 4¯3m ), experimental, theoretical saturation magnetization (Msexp., Msth.), while decreases the grain size (Ds) and coercivity (Hc). With irradiation Msexp., Msth. increases but not much change are observed in Hc. New antistructure modeling for the pristine, irradiated Ni and Ni-Zn ferrite samples was used for describing the surface active centers.
Chen, Jianxiang; Wu, Defeng; Tam, Kam C; Pan, Keren; Zheng, Zhigong
2017-02-10
Ring-opening polymerization of l-lactide from cellulose nanocrystal (CNC) surface yielded polylactide-grafted CNC (CNC-g-PLA). The structure and chemical composition of the CNC-g-PLA were characterized by FT-IR, 1 H NMR, XPS and XRD. The crystallization behavior and lamellar structure of poly(β-hydroxybutyrate) (PHB) in the presence of pristine CNC and CNC-g-PLA were elucidated via DSC and SAXS, and Babinet's reciprocity theory was applied. Crystallization kinetics were further analyzed using Ozawa, Mo and Kissinger models. In the presence of pristine CNC, nucleation of PHB crystals led to an increase in the crystallization temperature (T c ) of PHB; while CNC-g-PLA acted as antinucleation agent, resulting in a remarkable reduction in T c of PHB. Accordingly, the composite with pristine CNC possessed a higher crystallization rate than neat PHB, while CNC-g-PLA displayed the lowest crystallization rate. However, the lamellar structure of PHB was not affected by the presence of pristine and modified CNCs, and almost identical crystallization activation energies as the neat PHB were observed, indicating that nucleation is dominant during PHB crystallization, instead of crystal growth. This study offers a promising approach of using pristine and modified CNCs to control the crystallization of biodegradable aliphatic polyesters. Copyright © 2016 Elsevier Ltd. All rights reserved.
Madin, Elizabeth M. P.; Gaines, Steven D.; Madin, Joshua S.; Link, Anne-Katrin; Lubchenco, Peggy J.; Selden, Rebecca L.; Warner, Robert R.
2012-01-01
Efforts to restore top predators in human-altered systems raise the question of whether rebounds in predator populations are sufficient to restore pristine foodweb dynamics. Ocean ecosystems provide an ideal system to test this question. Removal of fishing in marine reserves often reverses declines in predator densities and size. However, whether this leads to restoration of key functional characteristics of foodwebs, especially prey foraging behavior, is unclear. The question of whether restored and pristine foodwebs function similarly is nonetheless critically important for management and restoration efforts. We explored this question in light of one important determinant of ecosystem function and structure – herbivorous prey foraging behavior. We compared these responses for two functionally distinct herbivorous prey fishes (the damselfish Plectroglyphidodon dickii and the parrotfish Chlorurus sordidus) within pairs of coral reefs in pristine and restored ecosystems in two regions of these species' biogeographic ranges, allowing us to quantify the magnitude and temporal scale of this key ecosystem variable's recovery. We demonstrate that restoration of top predator abundances also restored prey foraging excursion behaviors to a condition closely resembling those of a pristine ecosystem. Increased understanding of behavioral aspects of ecosystem change will greatly improve our ability to predict the cascading consequences of conservation tools aimed at ecological restoration, such as marine reserves. PMID:22403650
An overview of dredging operations in the Chesapeake Bay. [environment effects and coastal ecology
NASA Technical Reports Server (NTRS)
Silver, R. H.
1978-01-01
Maintenance of the Baltimore and the Newport News/Norfolk harbors as well as of the Chesapeake and Delaware Canal is accomplished by different dredging operations which depend on the amount and type of material to be moved, water depth, and location of disposal sites. Methods for determining the physical or chemical-biological interactive effects of these activities on the environment and on the shellfish and finfish industries on the Bay are discussed. The types of dredges used are classed according to their mode of operation.
Simonini, R; Ansaloni, I; Cavallini, F; Graziosi, F; Iotti, M; Massamba N'siala, G; Mauri, M; Montanari, G; Preti, M; Prevedelli, D
2005-12-01
Sediment from harbors of the Emilia-Romagna (Northern Adriatic Sea) were dredged and dumped in four disposal areas characterized by muddy bottoms. The long-term effects of the dumping on macrozoobenthic communities were investigated before and after 6 month, 8 month, 2 years and 4 years. The disposal of dredged material did not influence the granulometry and %TOC in the sediment, and no alterations in the structure of the macrobenthic communities were observed in the four areas. The lack of impact could be ascribed to the environmental characteristics and precautionary measures taken to minimize the effects of the dumping. It appears that: (1) the communities of the dumping areas are well adapted to unstable environments; (2) the sediments were disposed gradually and homogeneously over relatively large areas; Other factors that help to reduce the impact of sediment disposal are the low concentrations of contaminants in dredged materials and the similarity of sediment in the dredged and disposal areas. Off-shore discharge appears a sustainable strategy for the management of uncontaminated dredged sediments from the Northern Adriatic Sea harbors.
Surface and Internal Structure of Pristine Presolar Silicon Carbide
NASA Astrophysics Data System (ADS)
Stroud, R. M.; Bernatowicz, T. J.
2005-03-01
We report results from transmission electron microcopy studies of the surface and internal structure of two pristine presolar SiC grains, including definitive evidence of an oxide rim on one grain, and the presence of internal TiC and AlN grains.
Cochran, Susan A.; Gibbs, Ann E.; Logan, Joshua B.
2006-01-01
In cooperation with the U.S. National Park Service (NPS), the U.S. Geological Survey (USGS) has mapped the underwater environment in and adjacent to three parks along the Kona coast on the island of Hawai‘i. This report is the second of two produced for the NPS on the geologic resource evaluation of Pu‘ukoholā Heiau National Historic Site (PUHE) and presents benthic habitat mapping of the waters of Kawaihae Bay offshore of PUHE. See Part I (Richmond and others, 2006) for an overview of the regional geology, local volcanics, and a detailed description of coastal landforms in the park. PUHE boundaries do not officially extend into the marine environment; however, impacts downslope of any activity in the park are of concern to management. The area of Kawaihae Bay mapped for this report extends from the north edge of the U.S. Coast Guard Reservation north of Kawaihae Harbor approximately 3.5 km south to the north edge of the Mauna Kea Golf Course and Beach Resort at Waikoloa and from the shoreline to depths of approximately 40 m (130 ft), where the fore reef drops off to the sandy shelf. The waters of smaller Pelekane Bay directly offshore of the park, while not formally under NPS jurisdiction, are managed by the park under an agreement with the State. This embayment is described in greater detail because of its special resource status. PUHE lies within the Kawaihae watershed, which contributes ~75 percent of the drainage in the northern portion of the study area; the Waikoloa/Waiulaula watershed contributes ~25 percent in the southern portion of the study area. Drainages from these watersheds into the study area include Makahuna, Makeāhua, Pohaukole, Kukui, and Waikoloa/Waiulaula Gulches. The Waikoloa/Waiulaula Gulch is the only perennial stream with a year-round water flow. Only during periods of extreme rainfall will water flow in the Makeāhua and Pohaukole gulches, merge together in the park, and empty directly into Pelekane Bay. In the late 1950s the reef off of PUHE was dredged to construct Kawaihae Harbor. Coral rubble was used in the construction of causeways and a revetment wall surrounding the commercial harbor. In the late 1960s the reef near Pelekane was blasted to create a small-boat harbor adjacent to the larger commercial harbor. Damage from these activities, in addition to a change in circulation patterns, has led to problems of high turbidity in Pelekane Bay.
Atomistic Modeling of Thermal Conductivity of Epoxy Nanotube Composites
NASA Astrophysics Data System (ADS)
Fasanella, Nicholas A.; Sundararaghavan, Veera
2016-05-01
The Green-Kubo method was used to investigate the thermal conductivity as a function of temperature for epoxy/single wall carbon nanotube (SWNT) nanocomposites. An epoxy network of DGEBA-DDS was built using the `dendrimer' growth approach, and conductivity was computed by taking into account long-range Coulombic forces via a k-space approach. Thermal conductivity was calculated in the direction perpendicular to, and along the SWNT axis for functionalized and pristine SWNT/epoxy nanocomposites. Inefficient phonon transport at the ends of nanotubes is an important factor in the thermal conductivity of the nanocomposites, and for this reason discontinuous nanotubes were modeled in addition to long nanotubes. The thermal conductivity of the long, pristine SWNT/epoxy system is equivalent to that of an isolated SWNT along its axis, but there was a 27% reduction perpendicular to the nanotube axis. The functionalized, long SWNT/epoxy system had a very large increase in thermal conductivity along the nanotube axis (~700%), as well as the directions perpendicular to the nanotube (64%). The discontinuous nanotubes displayed an increased thermal conductivity along the SWNT axis compared to neat epoxy (103-115% for the pristine SWNT/epoxy, and 91-103% for functionalized SWNT/epoxy system). The functionalized system also showed a 42% improvement perpendicular to the nanotube, while the pristine SWNT/epoxy system had no improvement over epoxy. The thermal conductivity tensor is averaged over all possible orientations to see the effects of randomly orientated nanotubes, and allow for experimental comparison. Excellent agreement is seen for the discontinuous, pristine SWNT/epoxy nanocomposite. These simulations demonstrate there exists a threshold of the SWNT length where the best improvement for a composite system with randomly oriented nanotubes would transition from pristine SWNTs to functionalized SWNTs.
Gurgel, Bruno César de Vasconcelos; Gonçalves, Patrícia Furtado; Pimentel, Suzana Peres; Nociti, Francisco Humberto; Sallum, Enilson Antonio; Sallum, Antonio Wilson; Casati, Marcio Zaffalon
2008-07-01
The aim of the present study was to histometrically evaluate bone healing in the absence of bone defects and in the presence of surgically created bone defects treated by guided bone regeneration at oxidized and turned implant surfaces. Three months after dental extractions, standardized buccal dehiscence defects (height: 5 mm; width: 4 mm) were surgically created following implant site preparation in the mandible of 10 dogs. Oxidized-surface implants (OSI) and turned-surface implants (TSI) were inserted bilaterally, and the bone defects were treated by guided bone regeneration. After 3 months of healing, the animals were sacrificed, blocks were dissected, and undecalcified sections were obtained and processed for histometric analysis. The percentage of bone-to-implant contact (BIC) and bone density (BD) was evaluated inside the threads on the buccal (regenerated bone) and lingual sides (pristine bone) of the implants. Data were evaluated using two-way analysis of variance (P <0.05). New bone formation could be observed in OSI and TSI in the region of the defect creation. The BIC values observed in OSI for pristine and regenerated bone were 57.03% +/- 21.86% and 40.86% +/- 22.73%, respectively. TSI showed lower values of BIC in pristine bone (37.39% +/- 23.33%) and regenerated bone (3.52% +/- 4.87%). The differences between OSI and TSI were statistically significant. BD evaluation showed no statistically significant differences between OSI and TSI in pristine and regenerated bone. The oxidized implant surface promoted a higher level of BIC than the turned implant surface at pristine and regenerated bone.
A ceramic matrix composite thermal protection system for hypersonic vehicles
NASA Technical Reports Server (NTRS)
Riccitiello, Salvatore R.; Love, Wendell L.; Pitts, William C.
1993-01-01
The next generation of hypersonic vehicles (NASP, SSTO) that require reusable thermal protection systems will experience acreage surface temperatures in excess of 1100 C. More important, they will experience a more severe physical environment than the Space Shuttle due to non-pristine launching and landing conditions. As a result, maintenance, inspection, and replacement factors must be more thoroughly incorporated into the design of the TPS. To meet these requirements, an advanced thermal protection system was conceived, designated 'TOPHAT'. This system consists of a toughened outer ceramic matrix composite (CMC) attached to a rigid reusable surface insulator (RSI) which is directly bonded to the surface. The objective of this effort was to evaluate this concept in an aeroconvective environment, to determine the effect of impacts to the CMC material, and to compare the results with existing thermal protection systems.
Jha, Dilip Kumar; Vinithkumar, Nambali Valsalan; Sahu, Biraja Kumar; Dheenan, Palaiya Sukumaran; Das, Apurba Kumar; Begum, Mehmuna; Devi, Marimuthu Prashanthi; Kirubagaran, Ramalingam
2015-07-15
Chidiyatappu Bay is one of the least disturbed marine environments of Andaman & Nicobar Islands, the union territory of India. Oceanic flushing from southeast and northwest direction is prevalent in this bay. Further, anthropogenic activity is minimal in the adjoining environment. Considering the pristine nature of this bay, seawater samples collected from 12 sampling stations covering three seasons were analyzed. Principal Component Analysis (PCA) revealed 69.9% of total variance and exhibited strong factor loading for nitrite, chlorophyll a and phaeophytin. In addition, analysis of variance (ANOVA-one way), regression analysis, box-whisker plots and Geographical Information System based hot spot analysis further simplified and supported multivariate results. The results obtained are important to establish reference conditions for comparative study with other similar ecosystems in the region. Copyright © 2015 Elsevier Ltd. All rights reserved.
NASA Technical Reports Server (NTRS)
Gudimenko, Y.; Ng, R.; Iskanderova, Z.; Kleiman, J.; Grigorevsky, A.; Kiseleva, L.; Finckenor, M.; Edwards, D.
2005-01-01
Research has been continued to further improve the space durability of conductive and non-conductive polymer-based paints and of conductive thermal control paints for space applications. Efforts have been made to enhance the space durability and stability of functional Characteristics in ground-based space environment imitating conditions, using specially developed surface modification treatment. The results of surface modification of new conductive paints, including the ground-based testing in aggressive oxidative environments, such as atomic oxygen/UV and oxygen plasma, and performance evaluation are presented. Functional properties and performance characteristics, such as thermal optical properties (differential solar absorptance and thermal emittance representing the thermal optical performance of thermal control paints) and surface resistivity characteristics of pristine, surface modified, and tested materials were verified. Extensive surface analysis studies have been performed using complementary surface analyses including SEM/EDS and XPS. Test results revealed that the successfully treated materials exhibit reduced mass loss and no surface morphology change, thus indicating good protection from the severe oxidative environment. It was demonstrated that the developed surface modification treatment could be applied successfully to charge dissipative and conductive paints.
NASA Astrophysics Data System (ADS)
Netsou, Asteriona-Maria; Thupakula, Umamahesh; Debehets, Jolien; Chen, Taishi; Hirsch, Brandon; Volodin, Alexander; Li, Zhe; Song, Fengqi; Seo, Jin Won; De Feyter, Steven; Schouteden, Koen; Van Haesendonck, Chris
2017-08-01
We investigated the topological insulator (TI) Bi2Te3 in four different environments (ambient, ultra-high vacuum (UHV), nitrogen gas and organic solvent environment) using scanning probe microscopy (SPM) techniques. Upon prolonged exposure to ambient conditions and organic solvent environments the cleaved surface of the pristine Bi2Te3 is observed to be strongly modified during SPM measurements, while imaging of freshly cleaved Bi2Te3 in UHV and nitrogen gas shows considerably less changes of the Bi2Te3 surface. We conclude that the reduced surface stability upon exposure to ambient conditions is triggered by adsorption of molecular species from ambient, including H2O, CO2, etc which is verified by Auger electron spectroscopy. Our findings of the drastic impact of exposure to ambient on the Bi2Te3 surface are crucial for further in-depth studies of the intrinsic properties of the TI Bi2Te3 and for potential applications that include room temperature TI based devices operated under ambient conditions.
The Active Bacterial Community in a Pristine Confined Aquifer
This study of the active bacteria residing in a pristine confined aquifer provides unexpected insights into the ecology of iron-reducing and sulfate-reducing bacteria in the subsurface. At 18 wells in east-central Illinois, we trapped the microbes that attached to aquifer sedimen...
NASA Astrophysics Data System (ADS)
Branfireun, Brian A.; Roulet, Nigel T.; Kelly, Carol. A.; Rudd, John W. M.
1999-09-01
Recent studies have found that "pristine" peatlands have high peat and pore water methylmercury (MeHg) concentrations and that peatlands may act as large sources of MeHg to the downstream aquatic system, depending upon the degree of hydrologie connectivity and catchment physiography. Sulphate-reducing bacteria have been implicated as principal methylators of inorganic mercury in many environments with previous research focused primarily on mercury methylation in aquatic sediments. Experiments in a poor fen in the Experimental Lakes Area, northwestern Ontario, Canada, demonstrated that the in situ addition of sulphate to peat and peat pore water resulted in a significant increase in pore water MeHg concentrations. As peatlands cover a large area of the Northern Hemisphere, this finding has potentially far ranging implications for the global mercury cycle, particularly in areas impacted by anthropogenically derived sulphate where the methylmercury fraction of total mercury species may be much larger than in nonimpacted environments.
NASA Astrophysics Data System (ADS)
Song, Ningning; Wang, Wucong; Wu, Yue; Xiao, Ding; Zhao, Yaping
2018-04-01
The hybrids of pristine graphene with polyaniline were synthesized by in situ polymerizations for making a high-performance supercapacitor. The formed high-ordered PANI nanocones were vertically aligned on the graphene sheets. The length of the PANI nanocones increased with the concentration of aniline monomer. The specific capacitance of the hybrids electrode in the three-electrode system was measured as high as 481 F/g at a current density of 0.1 A/g, and its stability remained 87% after constant charge-discharge 10000 cycles at a current density of 1 A/g. This outstanding performance is attributed to the coupling effects of the pristine graphene and the hierarchical structure of the PANI possessing high specific surface area. The unique structure of the PANI provided more charge transmission pathways and fast charge-transfer speed of electrons to the pristine graphene because of its large specific area exposed to the electrolyte. The hybrid is expected to have potential applications in supercapacitor electrodes.
Early lunar petrogenesis, oceanic and extraoceanic
NASA Technical Reports Server (NTRS)
Warren, P. H.; Wasson, J. T.
1980-01-01
An attempt is made to ascertain which (if any) pristine nonmare rocks, other than KREEPy ones, are not cumulates from the magma ocean. It is noted that the only pristine rocks having bulk densities low enough to have formed by floating above the magma ocean are the ferroan anorthosites, which are easily recognizable as a discrete subset of pristine rocks in general, on the basis of mineral composition relationships. The other class of pristine nonmare rocks, the Mg-rich rocks, did not form from the same magma that produced the ferroan anorthosites. It is suggested that they were formed in layered noritic-troctolitic plutons. These plutons, it is noted, were apparently intruded at, or slightly above, the boundary between the floated ferroan anorthosite crust and the underlying complementary mafic cumulates. It is thought that the parental magmas of the plutons may have arisen by partial melting of either deep mafic cumulates from the magma ocean or a still deeper, undifferentiated primordial layer that was not molten during the magma ocean period.
NASA Technical Reports Server (NTRS)
Anders, E.
1979-01-01
An attempt is made to show that Delano and Ringwood (1978) reached the conclusion that the siderophiles in the lunar highlands are mainly of indigenous rather than meteoric origin by stretching and chopping the evidence to fit a preconceived mold. In determining the abundance of siderophiles and volatiles in the lunar highlands, Delano and Ringwood rejected evidence supplied by pristine rocks uncontaminated by meteoric debris, on the basis that these rocks are impact melts. It is argued that there is no evidence that complete melting and slow freezing needed for settling of metal is ever attained in lunar impacts. Moreover, some of the meteorite-free rocks are clasts within, and hence older than the siderophile-rich breccias that Delano and Ringwood consider more pristine. If one uses the pristine highland rocks to determine an indigenous component, no problems with enrichment of Zn, Ge, As, Ag, Sb, and Au in the indigenous component relative to mare basalts are encountered, since the pristine rocks show no significant enrichment in these elements.
Sea-Floor Character and Sedimentary Processes in the Vicinity of Woods Hole, Massachusetts
Poppe, Lawrence J.; McMullen, Katherine Y.; Foster, David S.; Blackwood, Dann S.; Williams, S. Jeffress; Ackerman, Seth D.; Barnum, Steven R.; Brennan, Rick T.
2008-01-01
Continuous-coverage multibeam bathymetric models and sidescan-sonar imagery have been verified with high-resolution seismic-reflection profiles, sediment sampling, and bottom photography. Together these data layers provide detailed base maps that yield topographic, compositional, and environmental perspectives of the sea floor in the vicinity of Woods Hole, an important harbor and major passage between the Elizabeth Islands and Cape Cod, Massachusetts. Tidally dominated high-energy environments within Woods Hole have prevented deposition of Holocene marine sediments, exposed underlying glacial drift of the Buzzards Bay moraine, and winnowed finer grained sediments, leaving lag deposits of boulders and gravel. These conditions have also enlarged and preserved depressions in the moraine surface that were originally kettle holes and formed ebb-tidal deltas at the entrances to passages. Fields of transverse and barchanoid sand waves dominate across the southern part of the study area in Vineyard Sound, where benthic environments are characterized by processes associated with coarse-bedload transport. Transverse sand waves dominate near shoals where sediment supply is greater and have asymmetries that indicate that the shoals are shaped and maintained by clockwise gyres of net sediment transport. Barchanoid sand waves, which are most common where Holocene sediments are thinner, commonly align into elongate fields that have smaller isolated waves concentrated at the eastern ends and that progressively widen and have waveforms that increase in amplitude, wavelength, and complexity westward. The northern, protected parts of the Little and Inner Harbors are characterized by muddy sediment and processes associated with deposition. A pockmark field in Little Harbor and the muddy, organic-rich sediments that form a scarp along the edge of Parker Flat are evidence for the presence of submerged marsh deposits formed during the Holocene rise in sea level.
Benthic foraminifera as indicators of pollution in high latitude marine environments
NASA Astrophysics Data System (ADS)
Dijkstra, N.; Junttila, J.; Husum, K.; Carroll, J.; Klitgaard-Kristensen, D.; Hald, M.
2012-04-01
An increasing number of studies demonstrate the potential of benthic foraminifera to characterize ecological status. However, the use of benthic foraminifera as bio-indicators has previously not been tested in high latitudes. This research contributes to the development of foraminifera as a bio-monitoring technique for the Arctic region, as industrial activities in this region will increase in the coming years. Surface sediments (0-1 cm) from sites close to gas fields in the SW Barents Sea were studied. In addition, to elucidate the range from less to very affected, surface sediments from the harbor of the town of Hammerfest (70° N) were studied. At least 300 living benthic foraminifera from the size fraction 100 µm-1 mm were counted and identified at species level. Pollution levels (heavy metals and persistent organic pollutants) and sediment properties (grainsize and TOC) were also analyzed. Pollution levels at the sea floor in the SW Barents Sea are of background to good level (level I-II) according to the definitions by the Water Framework Directorate (WFD). Benthic foraminiferal assemblages are influenced by natural environmental parameters such as water mass properties, water depth, nutrient availability, bottom current strength, and grain size. Surface sediments from the Hammerfest harbor are of moderate environmental status (WFD level II-III) based on heavy metal concentrations and of bad environmental status (WFD IV-V) based on persistent organic pollutant concentrations. Opportunistic benthic foraminifera are dominating the assemblages. The most polluted areas in the harbor are barren for foraminifera or have high amounts of deformed shells. In both environments the foraminiferal diversity of the samples, does not correspond to expected environmental status based on the pollution levels of the sediments. Environmental status classes, based on benthic foraminifera instead of macrofauna, would allow rapid analyses of the environmental impact of pollution.
Young, Suzanne; Nayak, Bina; Sun, Shan; Badgley, Brian D; Rohr, Jason R; Harwood, Valerie J
2016-09-15
Sewage spills can release antibiotic-resistant bacteria into surface waters, contributing to environmental reservoirs and potentially impacting human health. Vancomycin-resistant enterococci (VRE) are nosocomial pathogens that have been detected in environmental habitats, including soil, water, and beach sands, as well as wildlife feces. However, VRE harboring vanA genes that confer high-level resistance have infrequently been found outside clinical settings in the United States. This study found culturable Enterococcus faecium harboring the vanA gene in water and sediment for up to 3 days after a sewage spill, and the quantitative PCR (qPCR) signal for vanA persisted for an additional week. Culturable levels of enterococci in water exceeded recreational water guidelines for 2 weeks following the spill, declining about five orders of magnitude in sediments and two orders of magnitude in the water column over 6 weeks. Analysis of bacterial taxa via 16S rRNA gene sequencing showed changes in community structure through time following the sewage spill in sediment and water. The spread of opportunistic pathogens harboring high-level vancomycin resistance genes beyond hospitals and into the broader community and associated habitats is a potential threat to public health, requiring further studies that examine the persistence, occurrence, and survival of VRE in different environmental matrices. Vancomycin-resistant enterococci (VRE) are harmful bacteria that are resistant to the powerful antibiotic vancomycin, which is used as a last resort against many infections. This study followed the release of VRE in a major sewage spill and their persistence over time. Such events can act as a means of spreading vancomycin-resistant bacteria in the environment, which can eventually impact human health. Copyright © 2016, American Society for Microbiology. All Rights Reserved.
Young, Suzanne; Nayak, Bina; Sun, Shan; Badgley, Brian D.; Rohr, Jason R.
2016-01-01
ABSTRACT Sewage spills can release antibiotic-resistant bacteria into surface waters, contributing to environmental reservoirs and potentially impacting human health. Vancomycin-resistant enterococci (VRE) are nosocomial pathogens that have been detected in environmental habitats, including soil, water, and beach sands, as well as wildlife feces. However, VRE harboring vanA genes that confer high-level resistance have infrequently been found outside clinical settings in the United States. This study found culturable Enterococcus faecium harboring the vanA gene in water and sediment for up to 3 days after a sewage spill, and the quantitative PCR (qPCR) signal for vanA persisted for an additional week. Culturable levels of enterococci in water exceeded recreational water guidelines for 2 weeks following the spill, declining about five orders of magnitude in sediments and two orders of magnitude in the water column over 6 weeks. Analysis of bacterial taxa via 16S rRNA gene sequencing showed changes in community structure through time following the sewage spill in sediment and water. The spread of opportunistic pathogens harboring high-level vancomycin resistance genes beyond hospitals and into the broader community and associated habitats is a potential threat to public health, requiring further studies that examine the persistence, occurrence, and survival of VRE in different environmental matrices. IMPORTANCE Vancomycin-resistant enterococci (VRE) are harmful bacteria that are resistant to the powerful antibiotic vancomycin, which is used as a last resort against many infections. This study followed the release of VRE in a major sewage spill and their persistence over time. Such events can act as a means of spreading vancomycin-resistant bacteria in the environment, which can eventually impact human health. PMID:27422829
Evaluation method for the potential functionome harbored in the genome and metagenome.
Takami, Hideto; Taniguchi, Takeaki; Moriya, Yuki; Kuwahara, Tomomi; Kanehisa, Minoru; Goto, Susumu
2012-12-12
One of the main goals of genomic analysis is to elucidate the comprehensive functions (functionome) in individual organisms or a whole community in various environments. However, a standard evaluation method for discerning the functional potentials harbored within the genome or metagenome has not yet been established. We have developed a new evaluation method for the potential functionome, based on the completion ratio of Kyoto Encyclopedia of Genes and Genomes (KEGG) functional modules. Distribution of the completion ratio of the KEGG functional modules in 768 prokaryotic species varied greatly with the kind of module, and all modules primarily fell into 4 patterns (universal, restricted, diversified and non-prokaryotic modules), indicating the universal and unique nature of each module, and also the versatility of the KEGG Orthology (KO) identifiers mapped to each one. The module completion ratio in 8 phenotypically different bacilli revealed that some modules were shared only in phenotypically similar species. Metagenomes of human gut microbiomes from 13 healthy individuals previously determined by the Sanger method were analyzed based on the module completion ratio. Results led to new discoveries in the nutritional preferences of gut microbes, believed to be one of the mutualistic representations of gut microbiomes to avoid nutritional competition with the host. The method developed in this study could characterize the functionome harbored in genomes and metagenomes. As this method also provided taxonomical information from KEGG modules as well as the gene hosts constructing the modules, interpretation of completion profiles was simplified and we could identify the complementarity between biochemical functions in human hosts and the nutritional preferences in human gut microbiomes. Thus, our method has the potential to be a powerful tool for comparative functional analysis in genomics and metagenomics, able to target unknown environments containing various uncultivable microbes within unidentified phyla.
Coliphage and indigenous phage in Mamala Bay, Oahu, Hawaii.
Paul, J H; Rose, J B; Jiang, S C; London, P; Xhou, X; Kellogg, C
1997-01-01
Public concern over the discharge of primarily treated sewage by two offshore outfalls in Mamala Bay, Oahu, prompted a multidisciplinary study to determine the impact of such activities on the water quality in the bay and at adjacent recreational beaches. As part of this study, we determined the abundance of coliphage as an indicator of fecal pollution along with total viral direct counts and phages infective for Vibrio parahaemoltyicus 16 at stations in Mamala Bay in four quarterly samplings over 13 months. Coliphage (< 1 to 1.2 x 10(3)/liter) were found during each quarterly sampling along an offshore transect to the Sand Island waste treatment facility outfall. The nonpoint coastal stations (Pearl Harbor, Ala Wai Canal, and Ke'ehi Lagoon) had high levels of coliphage during the storm event sampling in February 1994 but much lower levels or none when sampled during dry weather. Coliphage were absent at all samplings at Waikiki Beach and at the control station off Diamond Head. Viral direct counts in eutrophic coastal stations (Pearl Harbor, Ke'ehi Lagoon, Ala Moana Beach, and Ala Wai canal) averaged 10(9)/liter, while counts at offshore stations ranged from 9 x 10(7) to 1 x 10(9) viruses/liter, values similar to those for other marine environments. Vibriophage were found mainly in eutrophic coastal environments (Ala Wai Canal, Pearl Harbor, and Ke'ehi Lagoon) and at the Sand Island Transect stations D1 and D2. The greatest abundance was found during the storm event (February 1994) sampling. These results suggest that the Sand Island outfall influenced the water quality of the immediate surrounding waters but had little effect on the quality of the recreational beaches. Nonpoint discharge sources appeared to be more important in the distribution of fecal indicators in the coastal zone.
NASA Astrophysics Data System (ADS)
Orzechowski, E. A.; Strauss, J. V.; Knoll, A. H.; Fischer, W. W.; Cantine, M.; Metcalfe, K.; Quinn, D. P.; Stein, N.; Gomes, M. L.; Grotzinger, H. M.; Lingappa, U.; O'Reilly, S. S.; Riedman, L. A.; Trower, L.; Grotzinger, J. P.
2016-12-01
The Caicos Platform's interior-platform ooid shoals and patch reef environments are unique modern examples of grain-rich carbonate settings. In July 2016, the Agouron Institute's Advanced Geobiology field course conducted a detailed study of Little Ambergris Cay, in the southeastern sector of the platform. The cay is fringed by a topographically high rim formed of amalgamated ridges of partially lithified fossiliferous grainstone and rudstone (i.e. beachrock conglomerate), that protects an interior basin dominated by microbial mats and mangroves. Tidal channels exchanging open platform waters with the interior basin breach the rim locally. We sampled and mapped the rim (using differential GPS) in order to examine its age, sedimentological characteristics, and faunal composition. Strata up to 2 meters above the present-day high tide mark form the rim, characterized by several carbonate lithofacies, including oolites with keystone vugs, high-angle trough cross bedding, seaward-dipping low angle stratification, bioturbation and fossiliferous lags, and rudstones composed of imbricated beachrock boulders. We interpret these facies as an upper shoreface to foreshore depositional setting dominated by local storm and eolian deposits. A distinct fossiliferous rudstone facies is dominated by mytilid bivalves, as well as Eustrombus, Conus, Oliva, and vermetid gastropods. X-ray powder diffraction analyses on fossil shells reveal both shells with pristine aragonite and shells with evidence of secondary calcite. Radiometric analyses of pristine aragonite material provide additional age constraints on these deposits. Understanding the formation of Little Ambergris Cay's bedrock deposits will provide important context for the island's geological history and geomorphology, aiding in our understanding of modern analogues for ancient interior platform depositional environments.
NASA Technical Reports Server (NTRS)
deGroh, Kim; Gaier, James R.; Hall, Rachelle L.; Norris, Mary Jo; Espe, Matthew P.; Cato, Daveen R.
1999-01-01
Metallized Teflon(Registered Trademark) FEP (fluorinated ethylene propylene) thermal control material on the Hubble Space Telescope (HST) is degrading in the space environment. Teflon(Registered Trademark) FEP thermal control blankets (space-facing FEP) retrieved during the first servicing mission (SM1) were found to be embrittled on solar facing surfaces and contained microscopic cracks. During the second servicing mission (SM2) astronauts noticed that the FEP outer layer of the multi-layer insulation (MLI) covering the telescope was cracked in many locations around the telescope. Large cracks were observed on the light shield, forward shell and equipment bays. A tightly curled piece of cracked FEP from the light shield was retrieved during SM2 and was severely embrittled, as witnessed by ground testing. A Failure Review Board (FRB) was organized to determine the mechanism causing the MLI degradation. Density, x-ray crystallinity and solid state nuclear magnetic resonance (NMR) analyses of FEP retrieved during SM1 were inconsistent with results of FEP retrieved during SM2. Because the retrieved SM2 material curled while in space, it experienced a higher temperature extreme during thermal cycling, estimated at 200 C, than the SM1 material, estimated at 50 C. An investigation on the effects of heating pristine and FEP exposed on HST was therefore conducted. Samples of pristine. SM1, and SM2 FEP were heated to 200 C and evaluated for changes in density and morphology. Elevated temperature exposure was found to have a major impact on the density of the retrieved materials. Characterization of polymer morphology of as-received and heated FEP samples by NMR provided results that were consistent with the density results. These findings have provided insight to the damage mechanisms of FEP in the space environment.
Federal Register 2010, 2011, 2012, 2013, 2014
2013-04-03
... document so that we can contact you if we have questions regarding your submission. To submit your comment... do not now plan to hold a public meeting. But you may submit a request for one, using one of the... that do not individually or cumulatively have a significant effect on the human environment. This...
Enric Batllori; Marc-Andre Parisien; Sean A. Parks; Max A. Moritz; Carol Miller
2017-01-01
Ongoing climate change may undermine the effectiveness of protected area networks in preserving the set of biotic components and ecological processes they harbor, thereby jeopardizing their conservation capacity into the future. Metrics of climate change, particularly rates and spatial patterns of climatic alteration, can help assess potential threats. Here, we perform...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Waldron, P.J.; Wu, L.; Van Nostrand, J.D.
2009-06-15
To understand how contaminants affect microbial community diversity, heterogeneity, and functional structure, six groundwater monitoring wells from the Field Research Center of the U.S. Department of Energy Environmental Remediation Science Program (ERSP; Oak Ridge, TN), with a wide range of pH, nitrate, and heavy metal contamination were investigated. DNA from the groundwater community was analyzed with a functional gene array containing 2006 probes to detect genes involved in metal resistance, sulfate reduction, organic contaminant degradation, and carbon and nitrogen cycling. Microbial diversity decreased in relation to the contamination levels of the wells. Highly contaminated wells had lower gene diversity butmore » greater signal intensity than the pristine well. The microbial composition was heterogeneous, with 17-70% overlap between different wells. Metal-resistant and metal-reducing microorganisms were detected in both contaminated and pristine wells, suggesting the potential for successful bioremediation of metal-contaminated groundwaters. In addition, results of Mantel tests and canonical correspondence analysis indicate that nitrate, sulfate, pH, uranium, and technetium have a significant (p < 0.05) effect on microbial community structure. This study provides an overall picture of microbial community structure in contaminated environments with functional gene arrays by showing that diversity and heterogeneity can vary greatly in relation to contamination.« less
Denitrification associated with stream periphyton: Chamber estimates from undisrupted communities
Duff, J.H.; Triska, F.J.; Oremland, R.S.
1984-01-01
Undisrupted periphyton communities from a N-rich (NO3- = 63 ??mol L-1) and pristine (NO3- = 2.9 ??mol L-1) stream were assayed for denitrifying activity (acetylene-blockage technique) in 40-L chambers incubated at in situ temperature and nutrient concentrations. Nitrous oxide formation associated with periphyton from the N-rich stream was immediate and linear (52.1 ??mol N2O m-2 h-1) in the dark, anaerobic chamber (50 kPa C2H2). In the corresponding light, aerobic chamber (50 kPa C2H2), N2O production was inhibited by 82% (9.3 ??mol N2O m-2 h-1). Nitrous oxide formation was not associated with periphyton from the pristine stream incubated in situ, either with or without NO3- amendment. Denitrification estimates made with undisrupted periphyton communities at in situ temperature and nutrient concentrations (40-L chambers) were less variable than estimates made with periphyton 'scrapings' in small flasks (room temperature). The calculated diel periphyton-associated denitrification rate based on a 14-h light-10-h dark day was 651 ??mol N2O m-2 d-1. The data suggest denitrification within periphyton mats may contribute toward removal of NO3- from N-rich fluvial environments.
NASA Astrophysics Data System (ADS)
Ollivia, S. L.; Juwono, A. L.; Roseno, Seto
2017-05-01
The use of synthetic fibers as reinforcement in composites has disadvantage which are unsustainable and an adverse impact on the environment. An alternative reinforcement for composites is natural fiber. Polypropylene and Sumberejo kenaf fibers were used respectively as the matrix and reinforcement. The aim of this research was to obtain the optimum tensile properties and deflection temperature with the variation of kenaf fiber fractions. Polypropylene/kenaf fiber composites were fabricated by hot press method. The kenaf fiber was soaked in NaOH solution before being used as the reinforcement and polypropylene was extruded before being used as the matrix. The weight fractions were varied to produce composites and pristine polypropylene samples were also prepared for comparison. The optimum tensile strength, modulus and deflection temperature were found in the composites with the 40 wt% kenaf fiber fraction with an increase up to 80% and 170% compared to the pristine polypropylene with the values of (60.3 ± 4,3) MPa and (159.1 ± 1,8) °C respectively. The Scanning Electron Microscope observation results in the fracture surface of the composites with the 40 wt% fiber fraction showed a relatively good bonding interface between fibers and the matrix and the failure modes were fiber breakage and matrix failures.
NASA Technical Reports Server (NTRS)
Mckay, D. S.; Rietmeijer, F. J. M.; Schramm, L. S.; Barrett, R. A.; Zook, H. A.; Blanford, G. E.
1986-01-01
The physical properties of impact features observed in the Solar Max main electronics box (MEB) thermal blanket generally suggest an origin by hypervelocity impact. The chemistry of micrometeorite material suggests that a wide variety of projectile materials have survived impact with retention of varying degrees of pristinity. Impact features that contain only spacecraft paint particles are on average smaller than impact features caused by micrometeorite impacts. In case both types of materials co-occur, it is belevied that the impact feature, generally a penetration hole, was caused by a micrometeorite projectile. The typically smaller paint particles were able to penetrate though the hole in the first layer and deposit in the spray pattern on the second layer. It is suggested that paint particles have arrived with a wide range of velocities relative to the Solar Max satellite. Orbiting paint particles are an important fraction of materials in the near-Earth environment. In general, the data from the Solar Max studies are a good calibration for the design of capture cells to be flown in space and on board Space Station. The data also suggest that development of multiple layer capture cells in which the projectile may retain a large degree of pristinity is a feasible goal.
NASA Astrophysics Data System (ADS)
Jeffries, Thomas C.; Ostrowski, Martin; Williams, Rohan B.; Xie, Chao; Jensen, Rachelle M.; Grzymski, Joseph J.; Senstius, Svend Jacob; Givskov, Michael; Hoeke, Ron; Philip, Gayle K.; Neches, Russell Y.; Drautz-Moses, Daniela I.; Chénard, Caroline; Paulsen, Ian T.; Lauro, Federico M.
2015-10-01
Microorganisms act both as drivers and indicators of perturbations in the marine environment. In an effort to establish baselines to predict the response of marine habitats to environmental change, here we report a broad survey of microbial diversity across the Indian Ocean, including the first microbial samples collected in the pristine lagoon of Salomon Islands, Chagos Archipelago. This was the first large-scale ecogenomic survey aboard a private yacht employing a ‘citizen oceanography’ approach and tools and protocols easily adapted to ocean going sailboats. Our data highlighted biogeographic patterns in microbial community composition across the Indian Ocean. Samples from within the Salomon Islands lagoon contained a community which was different even from adjacent samples despite constant water exchange, driven by the dominance of the photosynthetic cyanobacterium Synechococcus. In the lagoon, Synechococcus was also responsible for driving shifts in the metatranscriptional profiles. Enrichment of transcripts related to photosynthesis and nutrient cycling indicated bottom-up controls of community structure. However a five-fold increase in viral transcripts within the lagoon during the day, suggested a concomitant top-down control by bacteriophages. Indeed, genome recruitment against Synechococcus reference genomes suggested a role of viruses in providing the ecological filter for determining the β-diversity patterns in this system.
Jeffries, Thomas C; Ostrowski, Martin; Williams, Rohan B; Xie, Chao; Jensen, Rachelle M; Grzymski, Joseph J; Senstius, Svend Jacob; Givskov, Michael; Hoeke, Ron; Philip, Gayle K; Neches, Russell Y; Drautz-Moses, Daniela I; Chénard, Caroline; Paulsen, Ian T; Lauro, Federico M
2015-10-20
Microorganisms act both as drivers and indicators of perturbations in the marine environment. In an effort to establish baselines to predict the response of marine habitats to environmental change, here we report a broad survey of microbial diversity across the Indian Ocean, including the first microbial samples collected in the pristine lagoon of Salomon Islands, Chagos Archipelago. This was the first large-scale ecogenomic survey aboard a private yacht employing a 'citizen oceanography' approach and tools and protocols easily adapted to ocean going sailboats. Our data highlighted biogeographic patterns in microbial community composition across the Indian Ocean. Samples from within the Salomon Islands lagoon contained a community which was different even from adjacent samples despite constant water exchange, driven by the dominance of the photosynthetic cyanobacterium Synechococcus. In the lagoon, Synechococcus was also responsible for driving shifts in the metatranscriptional profiles. Enrichment of transcripts related to photosynthesis and nutrient cycling indicated bottom-up controls of community structure. However a five-fold increase in viral transcripts within the lagoon during the day, suggested a concomitant top-down control by bacteriophages. Indeed, genome recruitment against Synechococcus reference genomes suggested a role of viruses in providing the ecological filter for determining the β-diversity patterns in this system.
Jeffries, Thomas C.; Ostrowski, Martin; Williams, Rohan B.; Xie, Chao; Jensen, Rachelle M.; Grzymski, Joseph J.; Senstius, Svend Jacob; Givskov, Michael; Hoeke, Ron; Philip, Gayle K.; Neches, Russell Y.; Drautz-Moses, Daniela I.; Chénard, Caroline; Paulsen, Ian T.; Lauro, Federico M.
2015-01-01
Microorganisms act both as drivers and indicators of perturbations in the marine environment. In an effort to establish baselines to predict the response of marine habitats to environmental change, here we report a broad survey of microbial diversity across the Indian Ocean, including the first microbial samples collected in the pristine lagoon of Salomon Islands, Chagos Archipelago. This was the first large-scale ecogenomic survey aboard a private yacht employing a ‘citizen oceanography’ approach and tools and protocols easily adapted to ocean going sailboats. Our data highlighted biogeographic patterns in microbial community composition across the Indian Ocean. Samples from within the Salomon Islands lagoon contained a community which was different even from adjacent samples despite constant water exchange, driven by the dominance of the photosynthetic cyanobacterium Synechococcus. In the lagoon, Synechococcus was also responsible for driving shifts in the metatranscriptional profiles. Enrichment of transcripts related to photosynthesis and nutrient cycling indicated bottom-up controls of community structure. However a five-fold increase in viral transcripts within the lagoon during the day, suggested a concomitant top-down control by bacteriophages. Indeed, genome recruitment against Synechococcus reference genomes suggested a role of viruses in providing the ecological filter for determining the β-diversity patterns in this system. PMID:26481089
Role of Defects on Regioselectivity of Nano Pristine Graphene.
Kudur Jayaprakash, Gururaj; Casillas, Norberto; Astudillo-Sánchez, Pablo D; Flores-Moreno, Roberto
2016-11-17
Here analytical Fukui functions based on density functional theory are applied to investigate the redox reactivity of pristine and defected graphene lattices. A carbon H-terminated graphene structure (with 96 carbon atoms) and a graphene defected surface with Stone-Wales rearrangement and double vacancy defects are used as models. Pristine sp 2 -hybridized, hexagonal arranged carbon atoms exhibit a symmetric reactivity. In contrast, common carbon atoms at reconstructed polygons in Stone-Wales and double vacancy graphene display large reactivity variations. The improved reactivity and the regioselectivity at defected graphene is correlated to structural changes that caused carbon-carbon bond length variations at defected zones.
Transient electroluminescence on pristine and degraded phosphorescent blue OLEDs
NASA Astrophysics Data System (ADS)
Niu, Quan; Blom, Paul W. M.; May, Falk; Heimel, Paul; Zhang, Minlu; Eickhoff, Christian; Heinemeyer, Ute; Lennartz, Christian; Crǎciun, N. Irina
2017-11-01
In state-of-the-art blue phosphorescent organic light-emitting diode (PHOLED) device architectures, electrons and holes are injected into the emissive layer, where they are carried by the emitting and hole transporting units, respectively. Using transient electroluminescence measurements, we disentangle the contribution of the electrons and holes on the transport and efficiency of both pristine and degraded PHOLEDs. By varying the concentration of hole transporting units, we show that for pristine PHOLEDs, the transport is electron dominated. Furthermore, degradation of the PHOLEDs upon electrical aging is not related to the hole transport but is governed by a decrease in the electron transport due to the formation of electron traps.
Environmental assessment of creosote-treated pilings in the marine environment
DOE Office of Scientific and Technical Information (OSTI.GOV)
Butala, J.H.; Webb, D.A.; Jop, K.M.
1995-12-31
A comprehensive ecological risk assessment was conducted to evaluate the environmental impact of creosote-treated pilings in the marine environment at Moss Landing Harbor, Moss Landing, California. Four areas of investigation comprising the risk assessment were (1) evaluation of environmental conditions around existing creosote-treated pilings (2) investigating effects related to restoration of pilings (3) assessing creosote migration into surrounding environment, one year after pile-driving and (4) confirmation of creosote toxicity in laboratory studies. Biological and chemical evaluation of the impact of creosote-treated pilings was conducted on surface sheen, water column and sediment samples collected at Moss Landing Harbor. Water samples (surfacemore » sheen, water column and sediment pore water) were evaluated using short-term chronic exposures with Mysidopsis bahia, while bulk sediment samples were evaluated with 10-day sediment toxicity tests with Ampelisca abdita. Samples of surface, column water and sediment were analyzed for the constituents of creosote by GC mass spectrometry. In addition, a sample of neat material used to preserve treated pilings represented a reference for the polyaromatic hydrocarbons. Verification of organism response and analyses of field collected samples was performed by conducting 10-day A. abdita sediment and 7-day M. bahia elutriate exposures with creosote applied to clean sediment collected at Moss Landing, Evaluations were also performed to determine the effects of photoinduced toxicity on test organisms exposed to PAHs. The biological and analytical results of the field and laboratory exposures are being used to evaluate and determine risk of creosote-treated pilings on the marine environment.« less
Blanco, Guillermo; Lemus, Jesús A; Grande, Javier
2009-05-01
The spread of pathogens in the environment due to human activities (pathogen pollution) may be involved in the emergence of many diseases in humans, livestock and wildlife. When manure from medicated livestock and urban effluents is spread onto agricultural land, both residues of antibiotics and bacteria carrying antibiotic resistance may be introduced into the environment. The transmission of bacterial resistance from livestock and humans to wildlife remains poorly understood even while wild animals may act as reservoirs of resistance that may be amplified and spread in the environment. We determined bacterial resistance to antibiotics in wildlife using the red-billed chough Pyrrhocorax pyrrhocorax as a potential bioindicator of soil health, and evaluated the role of agricultural manuring with waste of different origins in the acquisition and characteristics of such resistance. Agricultural manure was found to harbor high levels of bacterial resistance to multiple antibiotics. Choughs from areas where manure landspreading is a common agricultural practice harbor a high bacterial resistance to multiple antibiotics, resembling the resistance profile found in the waste (pig slurry and sewage sludge) used in each area. The transfer of bacterial resistance to wildlife should be considered as an important risk for environmental health when agricultural manuring involves fecal material containing multiresistant enteric bacteria including pathogens from livestock operations and urban areas. The assessment of bacterial resistance in wild animals may be valuable for the monitoring of environmental health and for the management of emergent infectious diseases influenced by the impact of different human activities in the environment.
NASA Astrophysics Data System (ADS)
Chowdhury, Sugata; Simpson, Jeffrey; Einstein, T. L.; Walker, Angela R. Hight
2D-materials with controllable optical, electronic and magnetic properties are desirable for novel nanodevices. Here we studied these properties for both pristine and hydrogenated TaSe2 (TaSe2-H) monolayer (ML) in the framework of DFT using the PAW method. We considered uniaxial and biaxial tensile strain, as well as shear strain along the basal planes in the range between 1% and 16%. Previous theoretical works (e.g.) considered only symmetrical biaxial tensile. Pristine ML is ferromagnetic for uniaxial tensile strain along ◯ or ŷ. For tensile strain in ŷ, the calculated magnetic moments of the Ta atoms are twice those for the same strain in ◯. Under pure shear strain (expansion along ŷ and compression along ◯), a pristine ML is ferromagnetic, but becomes non-magnetic when the strain directions are interchanged. Due to carrier-mediated double-exchange, the pristine ML is ferromagnetic when the Se-Ta-Se bond angle is < 82° and the ML thickness is < 3.25Å. We find that all Raman-active phonon modes show obvious red-shifting due to bond elongation and the E2 modes degeneracy is lifted as strain increases. For a TaSe2-H ML, the same trends were observed. Results show the ability to tune the properties of 2D-materials.
Lessons from the Environmental Antibiotic Resistome.
Surette, Matthew D; Wright, Gerard D
2017-09-08
Antibiotic resistance is a global public health issue of growing proportions. All antibiotics are susceptible to resistance. The evidence is now clear that the environment is the single largest source and reservoir of resistance. Soil, aquatic, atmospheric, animal-associated, and built ecosystems are home to microbes that harbor antibiotic resistance elements and the means to mobilize them. The diversity and abundance of resistance in the environment is consistent with the ancient origins of antibiotics and a variety of studies support a long natural history of associated resistance. The implications are clear: Understanding the evolution of resistance in the environment, its diversity, and mechanisms is essential to the management of our existing and future antibiotic resources.
USDA-ARS?s Scientific Manuscript database
Honey bees and other pollinators are exposed to fungicides that act by inhibiting mitochondrial function. Here we test whether a common fungicide (Pristine®) inhibits the function of mitochondria of honeybees, and whether consumption of ecologically-realistic concentrations can cause negative eff...
Method for forming hermetic coatings for optical fibers
Michalske, Terry A.; Rye, Robert R.; Smith, William L.
1993-01-01
A method for forming hermetic coatings on optical fibers by hot filament assisted chemical vapor deposition advantageously produces a desirable coating while maintaining the pristine strength of the pristine fiber. The hermetic coatings may be formed from a variety of substances, such as, for example, boron nitride and carbon.
Bi, Fukun; Chen, Jing; Zhuang, Yin; Bian, Mingming; Zhang, Qingjun
2017-01-01
With the rapid development of optical remote sensing satellites, ship detection and identification based on large-scale remote sensing images has become a significant maritime research topic. Compared with traditional ocean-going vessel detection, inshore ship detection has received increasing attention in harbor dynamic surveillance and maritime management. However, because the harbor environment is complex, gray information and texture features between docked ships and their connected dock regions are indistinguishable, most of the popular detection methods are limited by their calculation efficiency and detection accuracy. In this paper, a novel hierarchical method that combines an efficient candidate scanning strategy and an accurate candidate identification mixture model is presented for inshore ship detection in complex harbor areas. First, in the candidate region extraction phase, an omnidirectional intersected two-dimension scanning (OITDS) strategy is designed to rapidly extract candidate regions from the land-water segmented images. In the candidate region identification phase, a decision mixture model (DMM) is proposed to identify real ships from candidate objects. Specifically, to improve the robustness regarding the diversity of ships, a deformable part model (DPM) was employed to train a key part sub-model and a whole ship sub-model. Furthermore, to improve the identification accuracy, a surrounding correlation context sub-model is built. Finally, to increase the accuracy of candidate region identification, these three sub-models are integrated into the proposed DMM. Experiments were performed on numerous large-scale harbor remote sensing images, and the results showed that the proposed method has high detection accuracy and rapid computational efficiency. PMID:28640236
Reed, J.A.; Flint, Paul L.
2007-01-01
We studied the movements and foraging effort of radio-marked Steller's Eiders (Polysticta stelleri) and Harlequin Ducks (Histrionicus histrionicus) to evaluate habitat quality in an area impacted by industrial activity near Dutch Harbor, Alaska. Foraging effort was relatively low, with Steller's Eiders foraging only 2.7 ± 0.6 (SE) hours per day and Harlequin Ducks 4.1 ± 0.5 hours per day. Low-foraging effort during periods of high-energetic demand generally suggests high food availability, and high food availability frequently corresponds with reductions in home range size. However, the winter ranges of Harlequin Ducks did not appear to be smaller than usual, with the mean range size in our study (5.5 ± 1.1 km2) similar to that reported by previous investigators. The mean size of the winter ranges of Steller's Eiders was similar (5.1 ± 1.3 km2), but no comparable estimates are available. Eutrophication of the waters near Dutch Harbor caused by seafood processing and municipal sewage effluent may have increased populations of the invertebrate prey of these sea ducks and contributed to their low-foraging effort. The threat of predation by Bald Eagles (Haliaeetus leucocephalus) that winter near Dutch Harbor may cause Steller's Eiders and Harlequin Ducks to move further offshore when not foraging, contributing to an increase in range sizes. Thus, the movement patterns and foraging behavior of these ducks likely represent a balance between the cost and benefits of wintering in a human-influenced environment.
Bi, Fukun; Chen, Jing; Zhuang, Yin; Bian, Mingming; Zhang, Qingjun
2017-06-22
With the rapid development of optical remote sensing satellites, ship detection and identification based on large-scale remote sensing images has become a significant maritime research topic. Compared with traditional ocean-going vessel detection, inshore ship detection has received increasing attention in harbor dynamic surveillance and maritime management. However, because the harbor environment is complex, gray information and texture features between docked ships and their connected dock regions are indistinguishable, most of the popular detection methods are limited by their calculation efficiency and detection accuracy. In this paper, a novel hierarchical method that combines an efficient candidate scanning strategy and an accurate candidate identification mixture model is presented for inshore ship detection in complex harbor areas. First, in the candidate region extraction phase, an omnidirectional intersected two-dimension scanning (OITDS) strategy is designed to rapidly extract candidate regions from the land-water segmented images. In the candidate region identification phase, a decision mixture model (DMM) is proposed to identify real ships from candidate objects. Specifically, to improve the robustness regarding the diversity of ships, a deformable part model (DPM) was employed to train a key part sub-model and a whole ship sub-model. Furthermore, to improve the identification accuracy, a surrounding correlation context sub-model is built. Finally, to increase the accuracy of candidate region identification, these three sub-models are integrated into the proposed DMM. Experiments were performed on numerous large-scale harbor remote sensing images, and the results showed that the proposed method has high detection accuracy and rapid computational efficiency.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gagne, F.; Burgeot, T.; Hellou, J.
2008-06-15
Economic and social developments have taken place at the expense of the health of the environment, both locally and on a global scale. In an attempt to better understand the large-scale effects of pollution and other stressors like climate change on the health status of Mytilus edulis, mussels were collected during the first two weeks of June 2005 at three sites (one pristine and two affected by pollution) located in each of the regions of the Canadian West Coast, the St. Lawrence estuary, the Atlantic East Coast and the northwestern coast of France, covering a total distance of some 11more » 000 km. The mussels were analyzed for morphologic integrity (condition factor), gametogenic activity (gonado-somatic and gonad maturation index, vitellogenin(Vtg)-like proteins), energy status (temperature-dependent mitochondrial electron transport activity and gonad lipid stores), defense mechanisms (glutathione S-transferase, metallothioneins, cytochrome P4503A activity and xanthine oxidoreductase-XOR), and tissue damage (lipid peroxidation-LPO and DNA strand breaks). The results showed that data from the reference sites in each region were usually not normally distributed, with discriminant factors reaching the number of regions (i.e. four), except for the biomarkers gonadal lipids, XOR and LPO in digestive gland. The integrated responses of the biomarkers revealed that biomarkers of stress were significantly more pronounced in mussels from the Seine estuary, suggesting that the impacts of pollution are more generalized in this area. Mussels from the Seine estuary and the Atlantic East Coast (Halifax Harbor) responded more strongly for Vtg-like proteins, but was not related to gonad maturation and gonado-somatic indexes, suggesting the presence of environmental estrogens. Moreover, these mussels displayed reduced DNA repair activity and increased LPO. Factorial analyses revealed that energy status, cytochrome P4503A activity and Vtg-like proteins were the most important biomarkers. Adaptation to warmer temperatures was reflected at the energy status levels, mussels from both the polluted and warmer sites displaying increased ratios of mitochondrial activity to lipid stores. Regional observations of biomarkers of energy status, gametogenesis and pollutant-related effects were influenced by nutrition, oxygen availability (eutrophication), and thermal history.« less
An Examination of the Impact of Drizzle Drops on Satellite-Retrieved Effective Particle Sizes
NASA Technical Reports Server (NTRS)
Minnis, Patrick; Arduini, Robert F.; Young, David F.; Ayers, J, Kirk; Albrecht, Bruce A.; Sharon, Tarah; Stevens, Bjorn
2004-01-01
In general, cloud effective droplet radii are remotely sensed in the near-infrared using the assumption of a monomodal droplet size distribution. It has been observed in many instances, especially in relatively pristine marine environments, that cloud effective droplet radii derived from satellite data often exceed 15 m or more. Comparisons of remotely sensed and in situ retrievals indicate that the former often overestimates the latter in clouds with drizzle-size droplets. To gain a better understanding of this discrepancy, this paper performs a theoretical and empirical evaluation of the impact of drizzle drops on the derived effective radius.
Thermal properties of black phosphorene and doped phosphorene (C, N & O): A DFT study
NASA Astrophysics Data System (ADS)
Devi, Anjna; Singh, Amarjeet
2018-04-01
In this work, we present the results from a DFT based computational study of pristine phosphorene and doped (C, N & O) phosphorene. We systematically investigated the lattice thermal properties of black phosphorene and the effect of doping on its thermal properties. We first determined the vibrational properties of pristine and doped phosphorene and from these results we calculated their thermal properties. We doped the phosphorene with C, N and O and observed that the structural stability of doped phosphorene decreases, while the thermal stability is increased as compared to pristine phosphorene. The presence of finite temperature effects in the doped system can contribute to acceleration of progress in future nano-scale technology.
Co-doped phosphorene: Enhanced sensitivity of CO gas sensing
NASA Astrophysics Data System (ADS)
Lei, S. Y.; Luan, S.; Yu, H.
2018-03-01
First-principle calculation was carried out to systematically investigate carbon monoxide (CO) adsorption on pristine and cobalt (Co)-doped phosphorenes (Co-bP). Whether or not CO is adsorped, pristine phosphorene is a direct-band-gap semiconductor. However, the bandgap of Co-bP experiences direct-to-indirect transition after CO molecule adsorption, which will affect optical absorption considerably, implying that Co doping can enhance the sensitivity of phosphorene as a CO gas sensor. Moreover, Co doping can improve an adsorption energy of CO to 1.31 eV, as compared with pristine phosphorene (0.12 eV), also indicating that Co-bP is energetically favorable for CO gas sensing.
77 FR 41441 - Federal Property Suitable as Facilities To Assist the Homeless
Federal Register 2010, 2011, 2012, 2013, 2014
2012-07-13
...; need repairs Land Hawaii 3.15 Acres Joint Base Pearl Harbor Hickam Pearl Harbor HI 96818 Landholding... Harbor Hickam Pearl Harbor HI 96818 Landholding Agency: Navy Property Number: 77201220013 Status... is still in use by the Navy 2.77 Acres Joint Base Pearl Harbor Hickam Pearl Harbor HI 96818...
1974-12-01
34 - . .. .. . . . . . . -.. 2.523 In rocky crevices along the shore walls there are a variety of sedges, rushes, grasses, mosses, lichens ...our dre~tinn anid d!’aonal planu ~ for 1rand ’N r~ls Hxariors ihe a1tcrrat.v.e deacrit’,ed In’ tti..i; le.tter ealicatn. dipoa plans for ltii pollato-4
USDA-ARS?s Scientific Manuscript database
Biofilm forming bacteria resident to food processing facilities are a food safety concern due to the potential of biofilms to harbor foodborne bacterial pathogens. When cultured together, Ralstonia insidiosa, a strong biofilm former frequently isolated from produce processing environments, has been ...
Federal Register 2010, 2011, 2012, 2013, 2014
2011-03-25
... of the public, our workers, and the environment at all of our facilities. We share your conviction that a clear set of requirements and standards is vital for safe operations. In 2008, we began a... of DOE Standard 3009-94 into the text as a requirement, instead of as a safe harbor cited in Table 2...
Enhanced Photocatalytic Activity of Vacuum-activated TiO2 Induced by Oxygen Vacancies.
Dong, Guoyan; Wang, Xin; Chen, Zhiwu; Lu, Zhenya
2018-05-01
TiO 2 (Degussa P25) photocatalysts harboring abundant oxygen vacancies (Vacuum P25) were manufactured using a simple and economic Vacuum deoxidation process. Control experiments showed that temperature and time of vacuum deoxidation had a significant effect on Vacuum P25 photocatalytic activity. After 240 min of visible light illumination, the optimal Vacuum P25 photocatalysts (vacuum deoxidation treated at 330 °C for 3 h) reach as high as 94% and 88% of photodegradation efficiency for rhodamine B (RhB) and tetracycline, respectively, which are around 4.5 and 4.9 times as that of pristine P25. The XPS, PL and EPR analyses indicated that the oxygen vacancies were produced in the Vacuum P25 during the vacuum deoxidation process. The oxygen vacancy states can produce vacancy energy level located below the conduction band minimum, which resulting in the bandgap narrowing, thus extending the photoresponse wavelength range of Vacuum P25. The positron annihilation analysis indicated that the concentrations ratio of bulk and surface oxygen vacancies could be adjusted by changing the vacuum deoxidation temperature and time. Decreasing the ratio of bulk and surface oxygen vacancies was shown to improve photogenerated electron-hole pair separation efficiency, which leads to an obvious enhancement of the visible photocatalytic activities of Vacuum P25. © 2017 The American Society of Photobiology.
A ceramic matrix composite thermal protection system for hypersonic vehicles
DOE Office of Scientific and Technical Information (OSTI.GOV)
Riccitiello, S.R.; Love, W.L.; Pitts, W.C.
1993-07-01
The next generation of hypersonic vehicles (NASP, SSTO) that require reusable thermal protection systems will experience acreage surface temperatures in excess of 1100 C. More important, they will experience a more severe physical environment than the Space Shuttle due to non-pristine launching and landing conditions. As a result, maintenance, inspection, and replacement factors must be more thoroughly incorporated into the design of the TPS. To meet these requirements, an advanced thermal protection system was conceived, designated 'TOPHAT'. This system consists of a toughened outer ceramic matrix composite (CMC) attached to a rigid reusable surface insulator (RSI) which is directly bondedmore » to the surface. The objective of this effort was to evaluate this concept in an aeroconvective environment, to determine the effect of impacts to the CMC material, and to compare the results with existing thermal protection systems. 10 refs.« less
Contamination of the Arctic reflected in microbial metagenomes from the Greenland ice sheet
NASA Astrophysics Data System (ADS)
Hauptmann, Aviaja L.; Sicheritz-Pontén, Thomas; Cameron, Karen A.; Bælum, Jacob; Plichta, Damian R.; Dalgaard, Marlene; Stibal, Marek
2017-07-01
Globally emitted contaminants accumulate in the Arctic and are stored in the frozen environments of the cryosphere. Climate change influences the release of these contaminants through elevated melt rates, resulting in increased contamination locally. Our understanding of how biological processes interact with contamination in the Arctic is limited. Through shotgun metagenomic data and binned genomes from metagenomes we show that microbial communities, sampled from multiple surface ice locations on the Greenland ice sheet, have the potential for resistance to and degradation of contaminants. The microbial potential to degrade anthropogenic contaminants, such as toxic and persistent polychlorinated biphenyls, was found to be spatially variable and not limited to regions close to human activities. Binned genomes showed close resemblance to microorganisms isolated from contaminated habitats. These results indicate that, from a microbiological perspective, the Greenland ice sheet cannot be seen as a pristine environment.
Degradation of Spacesuit Fabrics in Low Earth Orbit
NASA Technical Reports Server (NTRS)
Gaier, James R.; Baldwin, Sammantha M.; Folz, Angela D.; Waters, Deborah L.; McCue, Terry R.; Jaworske, Donald A.; Clark, Gregory W.; Rogers, Kerry J.; Batman, Brittany; Bruce, John;
2012-01-01
Six samples of pristine and dust-abraded outer layer spacesuit fabrics were included in the Materials International Space Station Experiment-7, in which they were exposed to the wake-side low Earth orbit environment on the International Space Station (ISS) for 18 months in order to determine whether abrasion by lunar dust increases radiation degradation. The fabric samples were characterized using optical microscopy, optical spectroscopy, field emission scanning electron microscopy, atomic force microscopy, and tensile testing before and after exposure on the ISS. Comparison of pre- and post-flight characterizations showed that the environment darkened and reddened all six fabrics, increasing their integrated solar absorptance by 7 to 38 percent. There was a decrease in the ultimate tensile strength and elongation to failure of lunar dust abraded Apollo spacesuit fibers by a factor of four and an increase in the elastic modulus by a factor of two.
Pristine Igneous Rocks and the Early Differentiation of Planetary Materials
NASA Technical Reports Server (NTRS)
Warren, Paul H.
2005-01-01
Our studies are highly interdisciplinary, but are focused on the processes and products of early planetary and asteroidal differentiation, especially the genesis of the ancient lunar crust. The compositional diversity that we explore is the residue of process diversity, which has strong relevance for comparative planetology. Most of the accessible lunar crust consists of materials hybridized by impact-mixing. Our lunar research concentrates on the rare pristine (unmixed) samples that reflect the original genetic diversity of the early crust. Among HED basalts (eucrites and clasts in howardites), we distinguish as pristine the small minority that escaped the pervasive thermal metamorphism of the parent asteroid's crust. We have found a correlation between metamorphically pristine HED basalts and the similarly small minority of compositionally evolved "Stannern trend" samples, which are enriched in incompatible elements and titanium compared to main group eucrites, and yet have relatively high mg ratios. Other topics under investigation included: lunar and SNC (martian?) meteorites; igneous meteorites in general; impact breccias, especially metal-rich Apollo samples and polymict eucrites; siderophile compositions of the lunar and martian mantles; and planetary bulk compositions and origins.
NASA Astrophysics Data System (ADS)
Kumar, Astakala Anil; Kumar, Ashok; Quamara, J. K.
2018-02-01
In present study, we report dielectric, ferroelectric and pyroelectric behavior of pristine and La3+ containing barium stannate nanoparticles synthesized via wet chemical route involving cetyltriammonium bromide assisted thermal decomposition of binary precursors. The X-ray diffraction patterns of pristine and La3+ (2, 4 and 6 at%) doped BaSnO3 nanoparticles showed the formation of cubic perovskite phase. On substitution of Ba2+ lattice sites by La3+ at the La content of 6 at%, the sample exhibited fourfold increase in conductivity in comparison to pristine BaSnO3. Polarization hysteresis (P-E) curves of La containing barium stannate nanoparticles showed anti-ferroelectric behavior. The pyroelectric coefficient of pristine and La (2, 4 and 6 at%) containing BaSnO3 nanoparticles at 473 K were found to be 7.8, 11.6, 14.1 and 17.2 μCm-2K-1, respectively. Further, the responsivity and detectivity values were higher in comparison to the materials, such as AlN, GaN, CdS and ZnO.
Strain-mediated electronic properties of pristine and Mn-doped GaN monolayers
NASA Astrophysics Data System (ADS)
Sharma, Venus; Srivastava, Sunita
2018-04-01
Graphene-like two-dimensional (2D) monolayer structures GaN has gained enormous amount of interest due to high thermal stability and inherent energy band gap for practical applications. First principles calculations are performed to investigate the electronic structure and strain-mediated electronic properties of pristine and Mn-doped GaN monolayer. Binding energy of Mn dopant at various adsorption site is found to be nearly same indicating these sites to be equally favorable for adsorption of foreign atom. Depending on the adsorption site, GaN monolayer can act as p-type or n-type magnetic semiconductor. The tensile strength of both pristine and doped GaN monolayer (∼24 GPa) at ultimate tensile strain of 34% is comparable with the tensile strength of graphene. The in-plane biaxial strain modulate the energy band gap of both pristine and doped-monolayer from direct to indirect gap semiconductor and finally retendered theme into metal at critical value of applied strain. These characteristics make GaN monolayer to be potential candidate for the future applications in tunable optoelectronics.
Adsorbing H₂S onto a single graphene sheet: A possible gas sensor
DOE Office of Scientific and Technical Information (OSTI.GOV)
Reshak, A. H., E-mail: maalidph@yahoo.co.uk; Center of Excellence Geopolymer and Green Technology, School of Material Engineering, University Malaysia Perlis, 01007 Kangar, Perlis; Auluck, S.
2014-09-14
The electronic structure of pristine graphene sheet and the resulting structure of adsorbing a single molecule of H₂S on pristine graphene in three different sites (bridge, top, and hollow) are studied using the full potential linearized augmented plane wave method. Our calculations show that the adsorption of H₂S molecule on the bridge site opens up a small direct energy gap of about 0.1 eV at symmetry point M, while adsorption of H₂S on top site opens a gap of 0.3 eV around the symmetry point K. We find that adsorbed H₂S onto the hollow site of pristine graphene sheet causesmore » to push the conduction band minimum and the valence band maximum towards Fermi level resulting in a metallic behavior. Comparing the angular momentum decomposition of the atoms projected electronic density of states of pristine graphene sheet with that of H₂S–graphene for three different cases, we find a significant influence of the location of the H₂S molecule on the electronic properties especially the strong hybridization between H₂S molecule and graphene sheet.« less
Corrosion behavior of pristine and added MgB2 in Phosphate Buffered Saline Solution
NASA Astrophysics Data System (ADS)
Batalu, D.; Bojin, D.; Ghiban, B.; Aldica, G.; Badica, P.
2012-09-01
We have obtained by Spark Plasma Sintering (SPS), dense samples of MgB2 added with Ho2O3. Starting composition was (MgB2)0.975(HoO1.5)0.025 and we used addition powders with an average particle size below and above 100 nm. For Mg, pristine and added MgB2 samples we measured potentiodynamic polarization curves in Phosphate Buffered Saline (PBS) solution media at room temperature. MgB2 based composites show corrosion/ degradation effects. This behavior is in principle similar to Mg based alloys in the same media. Our work suggests that the different morphologies and phase compositions of the SPS-ed samples influence the interaction with corrosion medium; hence additions can play an important role in controlling the corrosion rate. Pristine MgB2 show a significant improvement of the corrosion resistance, if compared with Mg. The best corrosion resistance is obtained for pristine MgB2, followed by MgB2 with nano-Ho2O3 and μ-Ho2O3 additions.
77 FR 50916 - Safety Zone; Boston Harbor's Rock Removal Project, Boston Inner Harbor, Boston, MA
Federal Register 2010, 2011, 2012, 2013, 2014
2012-08-23
... DEPARTMENT OF HOMELAND SECURITY Coast Guard 33 CFR Part 165 [Docket No. USCG-2012-0767] RIN 1625-AA00 Safety Zone; Boston Harbor's Rock Removal Project, Boston Inner Harbor, Boston, MA AGENCY: Coast.... 165.T01-0767 Safety Zone; Boston Harbor's Rock Removal Project, Boston Inner Harbor, Boston, MA. (a...
A Brief Review of the Lithology and Petrology of the Tagish Lake Meteorite Type Specimen
NASA Astrophysics Data System (ADS)
Herd, R. K.
2009-05-01
The mineralogical and textural characteristics of the type specimen of the Tagish Lake meteorite were described previously [1,2]. These initial descriptions recognized two lithologies, one relatively carbonate-poor, and the other relatively carbonate-rich. In addition numerous lithic fragments within the main lithologies were noted, essentially brecciated fragments within brecciated fragments [2,3]. Most research on the meteorite has generally assumed that only two lithologies were present. Many preliminary mineral and organic analyses done on pristine and non-pristine samples cannot be related to a particular matrix -- neither to the two supposed to be present, nor to any others. Distinction has sometimes been made between chondrule-bearing lithologies or fragments, and non-chondrule-bearing, or so-called dark dusty, lithologies preserved in the pristine specimen suite. To aid in a systematic approach to understanding this unique meteorite, the main petrographic features of the type specimen polished section are reviewed, based on back-scattered electron (BSE) images and electron- microprobe (EM) analyses. What is still needed is a consortium study of the pristine and non-pristine samples, that would define all the lithologies present and their inter-relationships, within the complete specimen suite, as the context and framework for ongoing research. [1] Brown, P.G. et al. (2000) Science, 290, 320-325. [2] Herd, R.K. et al. (2001) LPS XXXII, Abstract 1928. [3] Herd, R.K. and Herd, C.D.K. (2007) LPS XXXVIII, Abstract 2347.
Kusano, Masahiro; Takizawa, Shota; Sakai, Tetsuya; Arao, Yoshihiko; Kubouchi, Masatoshi
2018-01-01
Since thermosetting resins have excellent resistance to chemicals, fiber reinforced plastics composed of such resins and reinforcement fibers are widely used as construction materials for equipment in chemical plants. Such equipment is usually used for several decades under severe corrosive conditions so that failure due to degradation may result. One of the degradation behaviors in thermosetting resins under chemical solutions is "corrosion-layer-forming" degradation. In this type of degradation, surface resins in contact with a solution corrode, and some of them remain asa corrosion layer on the pristine part. It is difficult to precisely measure the thickness of the pristine part of such degradation type materials by conventional pulse-echo ultrasonic testing, because the sound velocity depends on the degree of corrosion of the polymeric material. In addition, the ultrasonic reflection interface between the pristine part and the corrosion layer is obscure. Thus, we propose a pitch-catch method using a pair of normal and angle probes to measure four parameters: the thicknesses of the pristine part and the corrosion layer, and their respective sound velocities. The validity of the proposed method was confirmed by measuring a two-layer sample and a sample including corroded parts. The results demonstrate that the pitch-catch method can successfully measure the four parameters and evaluate the residual thickness of the pristine part in the corrosion-layer-forming sample. Copyright © 2017 Elsevier B.V. All rights reserved.
An autonomous vehicle approach for quantifying bioluminescence in ports and harbors
NASA Astrophysics Data System (ADS)
Moline, Mark; Bissett, Paul; Blackwell, Shelley; Mueller, James; Sevadjian, Jeff; Trees, Charles; Zaneveld, Ron
2005-05-01
Bioluminescence emitted from marine organisms upon mechanical stimulation is an obvious military interest, as it provides a low-tech method of identifying surface and subsurface vehicles and swimmer tracks. Clearly, the development of a passive method of identifying hostile ships, submarines, and swimmers, as well as the development of strategies to reduce the risk of detection by hostile forces is relevant to Naval operations and homeland security. The measurement of bioluminescence in coastal waters has only recently received attention as the platforms and sensors were not scaled for the inherent small-scale nature of nearshore environments. In addition to marine forcing, many ports and harbors are influenced by freshwater inputs, differential density layering and higher turbidity. The spatial and temporal fluctuations of these optical water types overlaid on changes in the bioluminescence potential make these areas uniquely complex. The development of an autonomous underwater vehicle with a bioluminescence capability allows measurements on sub-centimeter horizontal and vertical scales in shallow waters and provides the means to map the potential for detection of moving surface or subsurface objects. A deployment in San Diego Bay shows the influence of tides on the distribution of optical water types and the distribution of bioluminescent organisms. Here, these data are combined to comment on the potential for threat reduction in ports and harbors.
NASA Astrophysics Data System (ADS)
Kalligeris, Nikos; Lynett, Patrick
2017-11-01
Numerous historical accounts describe the formation of ``whirpools'' inside ports and harbors during tsunami events, causing port operation disruptions. Videos from the Japan 2011 tsunami revealed complex nearshore flow patters, resulting from the interaction of tsunami-induced currents with the man-made coastline, and the generation of large eddies (or turbulent coherent structures) in numerous ports and harbors near the earthquake epicenter. The aim of this work is to study the generation and evolution of tsunami-induced turbulent coherent structures (TCS) in a well-controlled environment using realistic scaling. A physical configuration is created in the image of a port entrance at a scale of 1:27 and a small-amplitude, long period wave creates a transient flow through the asymmetric harbor channel. A separated region forms, which coupled with the transient flow, leads to the formation of a stable monopolar TCS. The surface flow is examined through mono- and stereo-PTV techniques to extract surface velocity vectors. Surface velocity maps and vortex flow profiles are used to study the experimental TCS generation and evolution, and characterize the TCS structure. Analytical tools are used to describe the TCS growth rate and kinetic energy decay. This work was funded by the National Science Foundation NEES Research program, with Award Number 1135026.
Diversity in gut bacterial community of school-age children in Asia.
Nakayama, Jiro; Watanabe, Koichi; Jiang, Jiahui; Matsuda, Kazunori; Chao, Shiou-Huei; Haryono, Pri; La-Ongkham, Orawan; Sarwoko, Martinus-Agus; Sujaya, I Nengah; Zhao, Liang; Chen, Kang-Ting; Chen, Yen-Po; Chiu, Hsueh-Hui; Hidaka, Tomoko; Huang, Ning-Xin; Kiyohara, Chikako; Kurakawa, Takashi; Sakamoto, Naoshige; Sonomoto, Kenji; Tashiro, Kousuke; Tsuji, Hirokazu; Chen, Ming-Ju; Leelavatcharamas, Vichai; Liao, Chii-Cherng; Nitisinprasert, Sunee; Rahayu, Endang S; Ren, Fa-Zheng; Tsai, Ying-Chieh; Lee, Yuan-Kun
2015-02-23
Asia differs substantially among and within its regions populated by diverse ethnic groups, which maintain their own respective cultures and dietary habits. To address the diversity in their gut microbiota, we characterized the bacterial community in fecal samples obtained from 303 school-age children living in urban or rural regions in five countries spanning temperate and tropical areas of Asia. The microbiota profiled for the 303 subjects were classified into two enterotype-like clusters, each driven by Prevotella (P-type) or Bifidobacterium/Bacteroides (BB-type), respectively. Majority in China, Japan and Taiwan harbored BB-type, whereas those from Indonesia and Khon Kaen in Thailand mainly harbored P-type. The P-type microbiota was characterized by a more conserved bacterial community sharing a greater number of type-specific phylotypes. Predictive metagenomics suggests higher and lower activity of carbohydrate digestion and bile acid biosynthesis, respectively, in P-type subjects, reflecting their high intake of diets rich in resistant starch. Random-forest analysis classified their fecal species community as mirroring location of resident country, suggesting eco-geographical factors shaping gut microbiota. In particular, children living in Japan harbored a less diversified microbiota with high abundance of Bifidobacterium and less number of potentially pathogenic bacteria, which may reflect their living environment and unique diet.
NASA Astrophysics Data System (ADS)
Bowen, Lizabeth; Miles, A. Keith; Ballachey, Brenda; Waters, Shannon; Bodkin, James; Lindeberg, Mandy; Esler, Daniel
2018-01-01
The 1989 Exxon Valdez oil spill damaged a wide range of natural resources, including intertidal communities, and post-spill studies demonstrated acute and chronic exposure and injury to an array of species. Standard toxicological methods to evaluate petroleum contaminants have assessed tissue burdens, with fewer assays providing indicators of health or physiology, particularly when contaminant levels are low and chronic. Marine mussels are a ubiquitous and crucial component of the nearshore environment, and new genomic technologies exist to quantify molecular responses of individual mussels to stimuli, including exposure to polycyclic aromatic hydrocarbons (PAHs). We used gene-based assays of exposure and physiological function to assess chronic oil contamination using the Pacific blue mussel, Mytilus trossulus. We developed a diagnostic gene transcription panel to investigate exposure to PAHs and other contaminants and its effects on mussel physiology and health. During 2012-2015, we analyzed mussels from five field sites in western Prince William Sound, Alaska, with varying oil histories from the 1989 Exxon Valdez oil spill, and from three boat harbors in the area. Gene transcription patterns of mussels from harbors were consistent with elevated exposure to PAHs or other contaminants, whereas transcription patterns of mussels sampled from shorelines in areas affected by the oil spill indicated no PAH exposure.
Cronin, Katherine; van Ormondt, Maarten; Storlazzi, Curt D.; Presto, Katherine; Tonnon, Pieter K.; Rosati, Julie D.; Wang, Ping; Roberts, Tiffany M.
2011-01-01
Current regulations in California prohibit the disposal of more than 20% fine-grained sediment in the coastal zone; this threshold is currently being investigated to determine if this environmental regulation can be improved upon. A field monitoring and numerical modeling experiment took place late 2 009 to determine the fate of fine-grained dredge disposal material from Santa Cruz Harbor, California, U.S.A. A multi-nested, hydrodynamic-sediment transport modeling approach was used to simulate the direction and dispersal of the dredge plume. Result s show that the direction and dispersal of the plume was influenced by the wave climate, a large proportion of which moved in a easterly direction during wave events. Therefore it is vitally important to accurately simulate the tides, waves, currents, temperature and salinity when modeling the dispersal of the fine-grained dredge plume.
Trace Explosives Signatures from World War II Unexploded Undersea Ordnance
NASA Technical Reports Server (NTRS)
Darrach, M. R.; Chutjian, A.; Plett, G. A.
1998-01-01
Trace explosives signatures of TNT and DNT have been extracted from multiple sediment samples adjacent to unexploded undersea ordnance at Halifax Harbor, Canada. The ordnance was hurled into the harbor during a massive explosion some 50 years earlier, in 1945 after World War II had ended. Laboratory sediment extractions were made using the solid-phase microextraction (SPME) method in seawater and detection using the Reversal Electron Attachment Detection (READ) technique and, in the case of DNT, a commercial gas chromatograph/mass spectrometer (GC/MS). Results show that, after more than 50 years in the environment, ordnance that appeared to be physically intact gave good explosives signatures at the parts per billion level, whereas ordnance that had been cracked open during the explosion gave no signatures at the 10 parts per trillion sensitivity level. These measurements appear to provide the first reported data of explosives signatures from undersea unexploded ordnance.
Echolocation by the harbour porpoise: life in coastal waters.
Miller, Lee A; Wahlberg, Magnus
2013-01-01
The harbor porpoise is one of the smallest and most widely spread of all toothed whales. They are found abundantly in coastal waters all around the northern hemisphere. They are among the 11 species known to use high frequency sonar of relative narrow bandwidth. Their narrow biosonar beam helps isolate echoes from prey among those from unwanted items and noise. Obtaining echoes from small objects like net mesh, net floats, and small prey is facilitated by the very high peak frequency around 130 kHz with a wavelength of about 12 mm. We argue that such echolocation signals and narrow band auditory filters give the harbor porpoise a selective advantage in a coastal environment. Predation by killer whales and a minimum noise region in the ocean around 130 kHz may have provided selection pressures for using narrow bandwidth high frequency biosonar signals.
Echolocation by the harbour porpoise: life in coastal waters
Miller, Lee A.; Wahlberg, Magnus
2013-01-01
The harbor porpoise is one of the smallest and most widely spread of all toothed whales. They are found abundantly in coastal waters all around the northern hemisphere. They are among the 11 species known to use high frequency sonar of relative narrow bandwidth. Their narrow biosonar beam helps isolate echoes from prey among those from unwanted items and noise. Obtaining echoes from small objects like net mesh, net floats, and small prey is facilitated by the very high peak frequency around 130 kHz with a wavelength of about 12 mm. We argue that such echolocation signals and narrow band auditory filters give the harbor porpoise a selective advantage in a coastal environment. Predation by killer whales and a minimum noise region in the ocean around 130 kHz may have provided selection pressures for using narrow bandwidth high frequency biosonar signals. PMID:23596420
The Pristine survey - I. Mining the Galaxy for the most metal-poor stars
NASA Astrophysics Data System (ADS)
Starkenburg, Else; Martin, Nicolas; Youakim, Kris; Aguado, David S.; Allende Prieto, Carlos; Arentsen, Anke; Bernard, Edouard J.; Bonifacio, Piercarlo; Caffau, Elisabetta; Carlberg, Raymond G.; Côté, Patrick; Fouesneau, Morgan; François, Patrick; Franke, Oliver; González Hernández, Jonay I.; Gwyn, Stephen D. J.; Hill, Vanessa; Ibata, Rodrigo A.; Jablonka, Pascale; Longeard, Nicolas; McConnachie, Alan W.; Navarro, Julio F.; Sánchez-Janssen, Rubén; Tolstoy, Eline; Venn, Kim A.
2017-11-01
We present the Pristine survey, a new narrow-band photometric survey focused on the metallicity-sensitive Ca H&K lines and conducted in the Northern hemisphere with the wide-field imager MegaCam on the Canada-France-Hawaii Telescope. This paper reviews our overall survey strategy and discusses the data processing and metallicity calibration. Additionally we review the application of these data to the main aims of the survey, which are to gather a large sample of the most metal-poor stars in the Galaxy, to further characterize the faintest Milky Way satellites, and to map the (metal-poor) substructure in the Galactic halo. The current Pristine footprint comprises over 1000 deg2 in the Galactic halo ranging from b ˜ 30° to ˜78° and covers many known stellar substructures. We demonstrate that, for Sloan Digital Sky Survey (SDSS) stellar objects, we can calibrate the photometry at the 0.02-mag level. The comparison with existing spectroscopic metallicities from SDSS/Sloan Extension for Galactic Understanding and Exploration (SEGUE) and Large Sky Area Multi-Object Fiber Spectroscopic Telescope shows that, when combined with SDSS broad-band g and I photometry, we can use the CaHK photometry to infer photometric metallicities with an accuracy of ˜0.2 dex from [Fe/H] = -0.5 down to the extremely metal-poor regime ([Fe/H] < -3.0). After the removal of various contaminants, we can efficiently select metal-poor stars and build a very complete sample with high purity. The success rate of uncovering [Fe/H]SEGUE < -3.0 stars among [Fe/H]Pristine < -3.0 selected stars is 24 per cent, and 85 per cent of the remaining candidates are still very metal poor ([Fe/H]<-2.0). We further demonstrate that Pristine is well suited to identify the very rare and pristine Galactic stars with [Fe/H] < -4.0, which can teach us valuable lessons about the early Universe.
SU-FF-T-668: A Simple Algorithm for Range Modulation Wheel Design in Proton Therapy
DOE Office of Scientific and Technical Information (OSTI.GOV)
Nie, X; Nazaryan, Vahagn; Gueye, Paul
2009-06-01
Purpose: To develop a simple algorithm in designing the range modulation wheel to generate a very smooth Spread-Out Bragg peak (SOBP) for proton therapy.Method and Materials: A simple algorithm has been developed to generate the weight factors in corresponding pristine Bragg peaks which composed a smooth SOBP in proton therapy. We used a modified analytical Bragg peak function based on Monte Carol simulation tool-kits of Geant4 as pristine Bragg peaks input in our algorithm. A simple METLAB(R) Quad Program was introduced to optimize the cost function in our algorithm. Results: We found out that the existed analytical function of Braggmore » peak can't directly use as pristine Bragg peak dose-depth profile input file in optimization of the weight factors since this model didn't take into account of the scattering factors introducing from the range shifts in modifying the proton beam energies. We have done Geant4 simulations for proton energy of 63.4 MeV with a 1.08 cm SOBP for variation of pristine Bragg peaks which composed this SOBP and modified the existed analytical Bragg peak functions for their peak heights, ranges of R{sub 0}, and Gaussian energies {sigma}{sub E}. We found out that 19 pristine Bragg peaks are enough to achieve a flatness of 1.5% of SOBP which is the best flatness in the publications. Conclusion: This work develops a simple algorithm to generate the weight factors which is used to design a range modulation wheel to generate a smooth SOBP in protonradiation therapy. We have found out that a medium number of pristine Bragg peaks are enough to generate a SOBP with flatness less than 2%. It is potential to generate data base to store in the treatment plan to produce a clinic acceptable SOBP by using our simple algorithm.« less
Effects of the exposure of TiO2 nanoparticles on basil (Ocimum basilicum) for two generations.
Tan, Wenjuan; Du, Wenchao; Darrouzet-Nardi, Anthony J; Hernandez-Viezcas, Jose A; Ye, Yuqing; Peralta-Videa, Jose R; Gardea-Torresdey, Jorge L
2018-09-15
There is a lack of information about the transgenerational effects of titanium dioxide nanoparticles (nano-TiO 2 ) in plants. This study aimed to evaluate the impacts of successive exposure of nano-TiO 2 with different surface properties to basil (Ocimum basilicum). Seeds from plants exposed or re-exposed to pristine, hydrophobic, or hydrophilic nano-TiO 2 were cultivated for 65 days in soil unamended or amended with 750 mg·kg -1 of the respective particles. Plant growth, concentration of titanium and essential elements, as well as content of carbohydrates and chlorophyll were evaluated. There were no differences on Ti concentration in roots of plants sequentially exposed to pristine or hydrophobic nano-TiO 2 , or in roots of plants exposed to the corresponding particle, only in the second cycle. However, sequential exposure to hydrophilic particles resulted in 65.2% less Ti in roots, compared to roots of plants exposed the same particles, only in the second cycle. The Ti concentrations in shoots were similar in all treatments. On the other hand, pristine and hydrophilic particles reduced Mg in root by 115% and 81%, respectively, while pristine and hydrophobic particles reduced Ni in shoot by 84% and 75%, respectively, compared to unexposed plants in both cycles. Sequential exposure to pristine nano-TiO 2 increased stomatal conductance (214%, p ≤ 0.10), compared to plants that were never exposed. Hydrophobic and hydrophilic nano-TiO 2 reduced chlorophyll b (52%) and total chlorophyll (30%) but increased total sugar (186%) and reducing sugar (145%), compared to unexposed plants in both cycles. Sequential exposure to hydrophobic or hydrophilic nano-TiO 2 resulted in more adverse effects on photosynthesis but in positive effects on plant growth, compared to pristine nano-TiO 2 . Copyright © 2018 Elsevier B.V. All rights reserved.
Flaherty, Nicole L; Chandrasekaran, Akshaya; del Pilar Sosa Peña, Maria; Roth, Gary A; Brenner, Sara A; Begley, Thomas J; Melendez, J Andrés
2015-12-15
Continued expansion of the nanotechnology industry has necessitated the self-assessment of manufacturing processes, specifically in regards to understanding the health related aspects following exposure to nanomaterials. There exists a growing concern over potential occupational exposure in the semiconductor industry where Al2O3, CeO2 and SiO2 nanoparticles are commonly featured as part of the chemical mechanical planarization (CMP) process. Chronic exposure to toxicants can result not only in acute cytotoxicity but also initiation of a chronic inflammatory state associated with diverse pathologies. In the current investigation, pristine nanoparticles and CMP slurry formulations of Al2O3, SiO2 and CeO2 were employed to assess their ability to induce cytotoxicity, inflammatory responses and reactive oxygen species in a mouse alveolar macrophage cell model. The pristine nanoparticles and slurries were not intrinsically cytotoxic and did not generate free radicals but were found to act as scavengers in the presence of an oxidant stimulant. Al2O3 and SiO2 nanoparticles increased levels of pro-inflammatory cytokines while pristine SiO2 nanoparticles induced generation of F2-Isoprostanes. In co-treatment studies, the pristine nanomaterials modulated the response to the inflammatory stimulant lipopolysaccharide. The studies have established that pristine nanoparticles and slurries do not impact the cells in a similar way indicating that they should not be used as slurry substitutes in toxicity evaluations. Further, we have defined how an alveolar cell line, which would likely be the first challenged upon nanomaterial aerosolization, responds to diverse mixtures of nanomaterials. Moreover, our findings reinforce the importance of using multiple analytic methods to define the redox state of the cell following exposure to commonly used industrial nanomaterials and toxicants. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
Garrison, Virginia H.; Kroeger, Kevin D.; Fenner, Douglas; Craig, Peter
2007-01-01
Degradation of nearshore habitats is a serious problem in some areas of American Samoa, such as in Pago Pago Harbor on Tutuila Island, and is a smaller but chronic problem in other areas. Sedimentation, pollution, nutrient enrichment from surface runoff or groundwater, and trampling are the major factors causing the changes (Peshut and Brooks, 2005). On the outer islands of Ofu and Olosega (Manu’a Islands; Fig. 1), there is an interesting contrast between relatively pristine lagoon habitats not far from comparatively degraded lagoon habitats. To’aga lagoon on the southeast side of Ofu Island (Fig. 1) has clear waters, a high diversity of corals and fishes, no human habitations, and an undeveloped watershed with no streams. To’aga lagoon is within the boundaries of the National Park of American Samoa and is the site of long-term research on coral reef resilience and global climate change. Only 3 km to the east of To’aga is a degraded lagoon that fronts Olosega Village. The Olosega lagoon is similar in size but has significantly less live coral than To’aga, and blooms of filamentous algae have been reported to cover the Olosega lagoon/reef flat bottom (unpublished data, PC; Fig. 2). The islands are influenced by the same regional-scale and biogeochemical regimes, and both islands are remnants of a volcanic caldera (Craig, 2005). Thus, local factors operating on the scale of a kilometer or less are thought to be driving the differences observed between lagoons. Land disturbance is limited to a road linking the villages, the clearing of vegetation for buildings, and two village dump sites located on the narrow strip of land between the steep slopes of the islands and the shoreline; there is no industry or associated pollution on either island. Cesspools are used for sewage disposal. Nutrient enrichment (from cesspools) of groundwater and the lagoon, as well as trampling during gleaning of reef organisms, are possible factors affecting the spatial relief and benthic composition of the lagoons. A pristine lagoon site (To’aga) and two that may be influenced by adjacent human populations (Ofu and Olosega Villages) were selected for study.
Longo, G O; Morais, R A; Martins, C D L; Mendes, T C; Aued, A W; Cândido, D V; de Oliveira, J C; Nunes, L T; Fontoura, L; Sissini, M N; Teschima, M M; Silva, M B; Ramlov, F; Gouvea, L P; Ferreira, C E L; Segal, B; Horta, P A; Floeter, S R
2015-01-01
The Southwestern Atlantic harbors unique and relatively understudied reef systems, including the only atoll in South Atlantic: Rocas atoll. Located 230 km off the NE Brazilian coast, Rocas is formed by coralline red algae and vermetid mollusks, and is potentially one of the most "pristine" areas in Southwestern Atlantic. We provide the first comprehensive and integrative description of the fish and benthic communities inhabiting different shallow reef habitats of Rocas. We studied two contrasting tide pool habitats: open pools, which communicate with the open ocean even during low tides, thus more exposed to wave action; and closed pools, which remain isolated during low tide and are comparatively less exposed. Reef fish assemblages, benthic cover, algal turfs and fish feeding pressure on the benthos remarkably varied between open and closed pools. The planktivore Thalassoma noronhanum was the most abundant fish species in both habitats. In terms of biomass, the lemon shark Negaprion brevirostris and the omnivore Melichtys niger were dominant in open pools, while herbivorous fishes (mainly Acanthurus spp.) prevailed in closed pools. Overall benthic cover was dominated by algal turfs, composed of articulated calcareous algae in open pools and non-calcified algae in closed pools. Feeding pressure was dominated by acanthurids and was 10-fold lower in open pools than in closed pools. Besides different wave exposure conditions, such pattern could also be related to the presence of sharks in open pools, prompting herbivorous fish to feed more in closed pools. This might indirectly affect the structure of reef fish assemblages and benthic communities. The macroalgae Digenea simplex, which is uncommon in closed pools and abundant in the reef flat, was highly preferred in herbivory assays, indicating that herbivory by fishes might be shaping this distribution pattern. The variations in benthic and reef fish communities, and feeding pressure on the benthos between open and closed pools suggest that the dynamics in open pools is mostly driven by physical factors and the tolerance of organisms to harsh conditions, while in closed pools direct and indirect effects of species interactions also play an important role. Understanding the mechanisms shaping biological communities and how they scale-up to ecosystem functioning is particularly important on isolated near-pristine systems where natural processes can still be studied under limited human impact.
2003-06-04
KENNEDY SPACE CENTER, FLA. - At Port Canaveral, the Pressurized Module of the Japanese Experiment Module (JEM) is lifted out of the ship’s cargo hold. The container transport ship carrying JEM departed May 2 from Yokohama Harbor in Japan for the voyage to the United States. The National Space Development Agency of Japan (NASDA) developed the laboratory at the Tsukuba Space Center near Tokyo. The Pressurized Module is the first element of the JEM, named "Kibo" (Hope), to be delivered to KSC. The JEM is Japan's primary contribution to the Station. It will enhance the unique research capabilities of the orbiting complex by providing an additional environment for astronauts to conduct science experiments. The JEM also includes an exposed facility (platform) for space environment experiments, a robotic manipulator system, and two logistics modules. The various JEM components will be assembled in space over the course of three Shuttle missions.
One-step direct transfer of pristine single-walled carbon nanotubes for functional nanoelectronics.
Wu, Chung Chiang; Liu, Chang Hua; Zhong, Zhaohui
2010-03-10
We report a one-step direct transfer technique for the fabrication of functional nanoelectronic devices using pristine single-walled carbon nanotubes (SWNTs). Suspended SWNTs grown by the chemical vapor deposition (CVD) method are aligned and directly transferred onto prepatterned device electrodes at ambient temperature. Using this technique, we successfully fabricated SWNT electromechanical resonators with gate-tunable resonance frequencies. A fully suspended SWNT p-n diode has also been demonstrated with the diode ideality factor equal to 1. Our method eliminates the organic residues on SWNTs resulting from conventional lithography and solution processing. The results open up opportunities for the fundamental study of electron transport physics in ultraclean SWNTs and for room temperature fabrication of novel functional devices based on pristine SWNTs.
Comparison of Shallow Survey 2012 Multibeam Datasets
NASA Astrophysics Data System (ADS)
Ramirez, T. M.
2012-12-01
The purpose of the Shallow Survey common dataset is a comparison of the different technologies utilized for data acquisition in the shallow survey marine environment. The common dataset consists of a series of surveys conducted over a common area of seabed using a variety of systems. It provides equipment manufacturers the opportunity to showcase their latest systems while giving hydrographic researchers and scientists a chance to test their latest algorithms on the dataset so that rigorous comparisons can be made. Five companies collected data for the Common Dataset in the Wellington Harbor area in New Zealand between May 2010 and May 2011; including Kongsberg, Reson, R2Sonic, GeoAcoustics, and Applied Acoustics. The Wellington harbor and surrounding coastal area was selected since it has a number of well-defined features, including the HMNZS South Seas and HMNZS Wellington wrecks, an armored seawall constructed of Tetrapods and Akmons, aquifers, wharves and marinas. The seabed inside the harbor basin is largely fine-grained sediment, with gravel and reefs around the coast. The area outside the harbor on the southern coast is an active environment, with moving sand and exposed reefs. A marine reserve is also in this area. For consistency between datasets, the coastal research vessel R/V Ikatere and crew were used for all surveys conducted for the common dataset. Using Triton's Perspective processing software multibeam datasets collected for the Shallow Survey were processed for detail analysis. Datasets from each sonar manufacturer were processed using the CUBE algorithm developed by the Center for Coastal and Ocean Mapping/Joint Hydrographic Center (CCOM/JHC). Each dataset was gridded at 0.5 and 1.0 meter resolutions for cross comparison and compliance with International Hydrographic Organization (IHO) requirements. Detailed comparisons were made of equipment specifications (transmit frequency, number of beams, beam width), data density, total uncertainty, and IHO compliance. Results from an initial analysis indicate that more factors need to be considered to properly compare sonar quality from processed results than just utilizing the same vessel with the same vessel configuration. Survey techniques such as focusing the beams over a narrower beam width can greatly increase data quality. While each sonar manufacturer was required to meet Special Order IHO specifications, line spacing was not specified and allowed for a greater data density despite equipment specification.
Yang, Jinying; Li, Jing; Luan, Xiwu; Zhang, Yunbo; Gu, Guizhou; Xue, Rongrong; Zong, Mingyue; Klotz, Martin G.
2013-01-01
The South China Sea (SCS), the largest marginal sea in the Western Pacific Ocean, is a huge oligotrophic water body with very limited influx of nitrogenous nutrients. This suggests that sediment microbial N2 fixation plays an important role in the production of bioavailable nitrogen. To test the molecular underpinning of this hypothesis, the diversity, abundance, biogeographical distribution, and community structure of the sediment diazotrophic microbiota were investigated at 12 sampling sites, including estuarine, coastal, offshore, deep-sea, and methane hydrate reservoirs or their prospective areas by targeting nifH and some other functional biomarker genes. Diverse and novel nifH sequences were obtained, significantly extending the evolutionary complexity of extant nifH genes. Statistical analyses indicate that sediment in situ temperature is the most significant environmental factor influencing the abundance, community structure, and spatial distribution of the sediment nifH-harboring microbial assemblages in the northern SCS (nSCS). The significantly positive correlation of the sediment pore water NH4+ concentration with the nifH gene abundance suggests that the nSCS sediment nifH-harboring microbiota is active in N2 fixation and NH4+ production. Several other environmental factors, including sediment pore water PO43− concentration, sediment organic carbon, nitrogen and phosphorus levels, etc., are also important in influencing the community structure, spatial distribution, or abundance of the nifH-harboring microbial assemblages. We also confirmed that the nifH genes encoded by archaeal diazotrophs in the ANME-2c subgroup occur exclusively in the deep-sea methane seep areas, providing for the possibility to develop ANME-2c nifH genes as a diagnostic tool for deep-sea methane hydrate reservoir discovery. PMID:23064334
Paul, John H.; McLaughlin, Molly R.; Griffin, Dale W.; Lipp, Erin K.; Stokes, Rodger; Rose, Joan B.
2000-01-01
Viral tracer studies have been used previously to study the potential for wastewater contamination of surface marine waters in the Upper and Middle Florida Keys. Two bacteriophages, the marine bacteriophage φHSIC and the Salmonella phage PRD1, were used as tracers in injection well and septic tank studies in Saddlebunch Keys of the Lower Florida Keys and in septic tank studies in Boot Key Harbor, Marathon, of the Middle Keys. In Boot Key Harbor, both phages were detected in a canal adjacent to the seeded septic tank within 3 h 15 min of the end of the seed period. The tracer was then detected at all sampling sites in Boot Key Harbor, including one on the opposite side of U. S. Highway 1 in Florida Bay, and at an Atlantic Ocean beach outside Boot Key Harbor. Rates of migration based on first appearance of the phage ranged from 1.7 to 57.5 m h-1. In Saddlebunch Keys, φHSIC and PRD1 were used to seed a residential septic tank and a commercial injection well. The septic tank tracer was not found in any surface water samples. The injection well tracer was first detected at a site most distant from the seed site, a channel that connected Sugarloaf Sound with the Atlantic Ocean. The rate of tracer migration from the injection well to this channel ranged from 66.8 to 141 m h-1. Both tracer studies showed a rapid movement of wastewater from on-site sewage treatment and disposal systems in a southeasterly direction toward the reef tract and Atlantic Ocean, with preferential movement through tidal channels. These studies indicate that wastewater disposal systems currently in widespread use in the Florida Keys can rapidly contaminate the marine environment.
Norman, Paul J.; Parham, Peter
2012-01-01
Pinnipeds, marine carnivores, diverged from terrestrial carnivores ~45 million years ago, before their adaptation to marine environments. This lifestyle change exposed pinnipeds to different microbiota and pathogens, with probable impact on their MHC class I genes. Investigating this question, genomic sequences were determined for 71 MHC class I variants: 27 from harbor seal and 44 from gray seal. These variants form three MHC class I gene lineages, one comprising a pseudogene. The second, a candidate nonclassical MHC class I gene, comprises a nonpolymorphic transcribed gene related to dog DLA-79 and giant panda Aime-1906. The third is the diversity lineage, which includes 62 of the 71 seal MHC class I variants. All are transcribed, and they minimally represent six harbor and 12 gray seal MHC class I genes. Besides species-specific differences in gene number, seal MHC class I haplotypes exhibit gene content variation and allelic polymorphism. Patterns of sequence variation, and of positions for positively selected sites, indicate the diversity lineage genes are the seals’ classical MHC class I genes. Evidence that expansion of diversity lineage genes began before gray and harbor seals diverged is the presence in both species of two distinctive sublineages of diversity lineage genes. Pointing to further expansion following the divergence are the presence of species-specific genes and greater MHC class I diversity in gray seals than harbor seals. The elaboration of a complex variable family of classical MHC class I genes in pinnipeds contrasts with the single, highly polymorphic classical MHC class I gene of dog and giant panda, terrestrial carnivores. PMID:23001684
Nonuniform Deployment of Autonomous Agents in Harbor-Like Environments
2014-11-12
ith agent than to all other agents. Interested readers are referred to [55] for the comprehensive study on Voronoi partitioning and its applications...robots: An rfid approach, PhD dissertation, School of Electrical Engi- neering and Computer Science, University of Ottawa (October 2012). [55] A. Okabe, B...Gueaieb, A stochastic approach of mobile robot navigation using customized rfid sys- tems, International Conference on Signals, Circuits and Systems
Methicillin-resistant Staphylococcus aureus survival on hospital fomites.
Huang, Robert; Mehta, Sanjay; Weed, Diane; Price, Connie Savor
2006-11-01
We examined the duration of survival of 2 strains of methicillin-resistant Staphylococcus aureus (MRSA) on 3 types of hospital fomites. MRSA survived for 11 days on a plastic patient chart, more than 12 days on a laminated tabletop, and 9 days on a cloth curtain. Irregular surfaces may help harbor organisms in the environment. In addition to contact precautions, MRSA containment during an outbreak should include concurrent environmental decontamination.
The Genomic Evolution of Prostate Cancer
2014-10-01
Mutation characteristics. (a) Number of high-confidence somatic mutations across all foci. Non- silent , non- silent mutations; Unique, number of unique...genes harboring a non- silent mutation; Reported, gene reported to be mutated in references 9–12 and 14. (b) Spectrum of unique high confidence somatic...epigenetic and micr- oRNA-mediated inactivation of LRP1B, a modulator of the extracellular environment of thyroid cancer cells. Oncogene 2011; 30
The Biological Fate and Effects of Organotin Compounds in the Marine Environment.
1983-07-01
estuarine bacteria (Pseudomonas) isolated from sediments in Baltimore Harbor. The bacterial isolates were found to accumulate tributyltin from 3.7-7.7 mg tin...monobutyltin) suggesting that the issolates accumulated but did not metabolize tributyltin . 2.3 Chemical Degradation Zuckerman et al. (1978) generalized... tributyltin fluoride in seawater. The compound was found to hydrolyze very rapidly in low concentrations in seawater to yield the chloride and oxide
Resources of dark skies in German climatic health resorts.
Gabriel, Katharina M A; Kuechly, Helga U; Falchi, Fabio; Wosniok, Werner; Hölker, Franz
2017-01-01
Illumination of nocturnal environments is increasing steadily worldwide. While there are some benefits for mankind, light at night affects animals, plants, and human health by blurring the natural distinction between day and night. International regulations exist to protect the environment for the maintenance of human health but nocturnal darkness is not considered. In Germany, cities and communities labeled as Climatic Health Resorts provide for high standards in air quality. However, their degree of nocturnal darkness is unexplored so far. In our study, we examined the degree of nocturnal darkness in German Climatic Health Resorts by two datasets based on georeferenced remote sensing data. The majority of Climatic Health Resorts (93.1 %) are able to offer a relative respite (≥ 20 mag/arcsec 2 ) from a degraded nocturnal environment, while only 3.4 % are able to offer a dark, if by no means pristine, night environment (≥ 21 mag/arcsec 2 ). Climatic Health Resorts emit less light as well as are less affected by night sky brightness compared to the average of non-classified communities. In combination with daytime requirements, the resorts provide conditions for a more distinct day-and-night-cycle than non-classified communities.
Persistent Organic Pollutants in Biotic and Abiotic Components of Antarctic Pristine Environment
NASA Astrophysics Data System (ADS)
Bhardwaj, Laxmikant; Chauhan, Abhishek; Ranjan, Anuj; Jindal, Tanu
2018-05-01
Over the past decades, research in Antarctica has built a new understanding of Antarctica, its past, present and future. Human activities and long-range pollutants are increasing on the Antarctic continent. Research on persistent organic pollutants (POPs) has been carried out internationally by several countries having their permanent research stations to explain the impact of an ever increasing range of POPs in Antarctic ecosystem. POPs have been detected in Antarctica despite its geographical isolation and almost complete absence of human settlements. The presence of POPs in different abiotic (atmosphere, water bodies, sediments, soil, sea ice) and biotic components (mosses, lichens, krill, penguins, skua, etc.) in Antarctica has been studied and documented around for decades and has either been banned or strictly regulated but is still found in the environment. This review focuses on recent research pertaining to sources and occurrence of POPs in Antarctic lake water, soil, sediment, lichen, mosses and other Antarctic marine community. This review also proposes to summarize the current state of research on POPs in Antarctica environment and draw the earliest conclusions on possible significance of POPs in Antarctica based on presently available information from related Antarctic environment.
Persistent Organic Pollutants in Biotic and Abiotic Components of Antarctic Pristine Environment
NASA Astrophysics Data System (ADS)
Bhardwaj, Laxmikant; Chauhan, Abhishek; Ranjan, Anuj; Jindal, Tanu
2018-02-01
Over the past decades, research in Antarctica has built a new understanding of Antarctica, its past, present and future. Human activities and long-range pollutants are increasing on the Antarctic continent. Research on persistent organic pollutants (POPs) has been carried out internationally by several countries having their permanent research stations to explain the impact of an ever increasing range of POPs in Antarctic ecosystem. POPs have been detected in Antarctica despite its geographical isolation and almost complete absence of human settlements. The presence of POPs in different abiotic (atmosphere, water bodies, sediments, soil, sea ice) and biotic components (mosses, lichens, krill, penguins, skua, etc.) in Antarctica has been studied and documented around for decades and has either been banned or strictly regulated but is still found in the environment. This review focuses on recent research pertaining to sources and occurrence of POPs in Antarctic lake water, soil, sediment, lichen, mosses and other Antarctic marine community. This review also proposes to summarize the current state of research on POPs in Antarctica environment and draw the earliest conclusions on possible significance of POPs in Antarctica based on presently available information from related Antarctic environment.
Stalder, Claudio; Rüggeberg, Andres; Neururer, Christoph; Spangenberg, Jorge E.; Spezzaferri, Silvia
2018-01-01
The marine environment in the Gulf of Gabes (southern Tunisia) is severely impacted by phosphate industries. Nowadays, three localities, Sfax, Skhira and Gabes produce phosphoric acid along the coasts of this Gulf and generate a large amount of phosphogypsum as a waste product. The Gabes phosphate industry is the major cause of pollution in the Gulf because most of the waste is directly discharged into the sea without preliminary treatment. This study investigates the marine environment in the proximity of the phosphate industries of Gabes and the coastal marine environment on the eastern coast of Djerba, without phosphate industry. This site can be considered as "pristine" and enables a direct comparison between polluted and “clean” adjacent areas. Phosphorous, by sequential extractions (SEDEX), Rock-Eval, C, H, N elemental analysis, and stable carbon isotope composition of sedimentary organic matter, X-ray diffraction (qualitative and quantitative analysis) were measured on sediments. Temperature, pH and dissolved oxygen were measured on the water close to the sea floor of each station to estimate environmental conditions. These analyses are coupled with video surveys of the sea floor. This study reveals clear differentiations in pollution and eutrophication in the investigated areas. PMID:29771969
Bio-nano interface and environment: A critical review.
Pulido-Reyes, Gerardo; Leganes, Francisco; Fernández-Piñas, Francisca; Rosal, Roberto
2017-12-01
The bio-nano interface is the boundary where engineered nanomaterials (ENMs) meet the biological system, exerting the biological function for which they have been designed or inducing adverse effects on other cells or organisms when they reach nontarget scenarios (i.e., the natural environment). Research has been performed to determine the fate, transport, and toxic properties of ENMs, but much of it is focused on pristine or so-called as-manufactured ENMs, or else modifications of the materials were not assessed. We review the most recent progress regarding the bio-nano interface and the transformations that ENMs undergo in the environment, paying special attention to the adsorption of environmental biomolecules on the surface of ENMs. Whereas the protein corona has received considerable attention in the fields of biomedics and human toxicology, its environmental analogue (the eco-corona) has been much less studied. A section dedicated to the analytical methods for studying and characterizing the eco-corona is also presented. We conclude by presenting and discussing the key problems and knowledge gaps that need to be resolved in the near future regarding the bio-nano interface and the eco-corona. Environ Toxicol Chem 2017;36:3181-3193. © 2017 SETAC. © 2017 SETAC.
NASA Astrophysics Data System (ADS)
Bouvy, M.; Got, P.; Domaizon, I.; Pagano, M.; Leboulanger, C.; Bouvier, C.; Carré, C.; Roques, C.; Dupuy, C.
2016-04-01
Coral reef environments are generally recognized as being the most threatened of marine ecosystems. However, it is extremely difficult to distinguish the effects of climate change from other forcing factors, mainly because it is difficult to study ecosystems that are isolated from human pressure. The five Iles Eparses (Scattered Islands) are located in the Western Indian Ocean (WIO) and can be considered to be "pristine" ecosystems not subject to anthropogenic pressure. This study characterized their plankton assemblages for the first time, by determining the abundances of microbial (virus, bacteria, heterotrophic protists and phytoplankton) and metazooplankton communities in various lagoon and ocean sites around each island. The Europa lagoon has extensive, productive mangrove forests, which have the highest nutrient concentrations (nitrogen forms, dissolved organic carbon) and whose microbial communities present a peculiar structure and functioning. By means of bioassay experiments, we observed that bacterial production and growth rates are higher in Europa than those reported for the other islands. Tromelin, which lies outside the Mozambique Channel, had the lowest biological productivity, nutrient concentrations, and bacterial growth rates. Multivariate analysis indicated that distinct microbial assemblages occur in association to varying nutrient concentrations. Molecular fingerprinting showed clear discrimination of the structure of the archaea, bacteria and eukaryotes community between the sites. Our results suggest that the geographical distance can influence the diversity of dominant microbial taxa in the WIO.
Observing Imperfection in Atomic Interfaces for van der Waals Heterostructures.
Rooney, Aidan P; Kozikov, Aleksey; Rudenko, Alexander N; Prestat, Eric; Hamer, Matthew J; Withers, Freddie; Cao, Yang; Novoselov, Kostya S; Katsnelson, Mikhail I; Gorbachev, Roman; Haigh, Sarah J
2017-09-13
Vertically stacked van der Waals heterostructures are a lucrative platform for exploring the rich electronic and optoelectronic phenomena in two-dimensional materials. Their performance will be strongly affected by impurities and defects at the interfaces. Here we present the first systematic study of interfaces in van der Waals heterostructure using cross-sectional scanning transmission electron microscope (STEM) imaging. By measuring interlayer separations and comparing these to density functional theory (DFT) calculations we find that pristine interfaces exist between hBN and MoS 2 or WS 2 for stacks prepared by mechanical exfoliation in air. However, for two technologically important transition metal dichalcogenide (TMDC) systems, MoSe 2 and WSe 2 , our measurement of interlayer separations provide the first evidence for impurity species being trapped at buried interfaces with hBN interfaces that are flat at the nanometer length scale. While decreasing the thickness of encapsulated WSe 2 from bulk to monolayer we see a systematic increase in the interlayer separation. We attribute these differences to the thinnest TMDC flakes being flexible and hence able to deform mechanically around a sparse population of protruding interfacial impurities. We show that the air sensitive two-dimensional (2D) crystal NbSe 2 can be fabricated into heterostructures with pristine interfaces by processing in an inert-gas environment. Finally we find that adopting glovebox transfer significantly improves the quality of interfaces for WSe 2 compared to processing in air.
The Physical Properties of Near-Pristine Gas at High Redshift
NASA Astrophysics Data System (ADS)
Cooke, Ryan; Pettini, Max
2012-02-01
High redshift damped Lyman alpha systems (DLAs) with metallicities less than 1/100 of solar are near-ideal environments for probing the nucleosynthesis by some of the first structures to form in the Universe. As part of our on-going survey of metal-poor DLAs, we have recently discovered a handful of quiescent DLAs that exhibit enhanced C/Fe ratios, with abundance patterns that are consistent with models of Population III star nucleosynthesis. Aside from their value as probes of the earliest episodes of star formation, the quiescent kinematics of these DLAs (σ ~ 2 km s^-1) provide us with a rare opportunity to decouple the turbulent and thermal broadening within the clouds by performing a differential analysis of the line widths for atoms of widely differing mass (such as deuterium and silicon). This will allow us to measure the gas temperature of these cold, near- pristine clouds of gas - a task that cannot be accomplished with other DLAs. By also measuring the gas density from the ratio of successive ion stages for multiple ions, we can begin to understand their origin and evolution, as well as the processes that heat and cool these clouds. As an additional bonus, we will also obtain two new measures of the primordial abundance of deuterium, building on the still meagre sample of such data from which the density of baryons in the Universe can be determined independently of CMB fluctuations.
33 CFR 80.1122 - Channel Islands Harbor, CA.
Code of Federal Regulations, 2012 CFR
2012-07-01
... INTERNATIONAL NAVIGATION RULES COLREGS DEMARCATION LINES Pacific Coast § 80.1122 Channel Islands Harbor, CA. (a) A line drawn from Channel Islands Harbor South Jetty Light 2 to Channel Islands Harbor Breakwater... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Channel Islands Harbor, CA. 80...
33 CFR 80.1122 - Channel Islands Harbor, CA.
Code of Federal Regulations, 2010 CFR
2010-07-01
... INTERNATIONAL NAVIGATION RULES COLREGS DEMARCATION LINES Pacific Coast § 80.1122 Channel Islands Harbor, CA. (a) A line drawn from Channel Islands Harbor South Jetty Light 2 to Channel Islands Harbor Breakwater... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Channel Islands Harbor, CA. 80...
33 CFR 80.1122 - Channel Islands Harbor, CA.
Code of Federal Regulations, 2014 CFR
2014-07-01
... INTERNATIONAL NAVIGATION RULES COLREGS DEMARCATION LINES Pacific Coast § 80.1122 Channel Islands Harbor, CA. (a) A line drawn from Channel Islands Harbor South Jetty Light 2 to Channel Islands Harbor Breakwater... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Channel Islands Harbor, CA. 80...
33 CFR 80.1122 - Channel Islands Harbor, CA.
Code of Federal Regulations, 2013 CFR
2013-07-01
... INTERNATIONAL NAVIGATION RULES COLREGS DEMARCATION LINES Pacific Coast § 80.1122 Channel Islands Harbor, CA. (a) A line drawn from Channel Islands Harbor South Jetty Light 2 to Channel Islands Harbor Breakwater... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Channel Islands Harbor, CA. 80...
33 CFR 80.1122 - Channel Islands Harbor, CA.
Code of Federal Regulations, 2011 CFR
2011-07-01
... INTERNATIONAL NAVIGATION RULES COLREGS DEMARCATION LINES Pacific Coast § 80.1122 Channel Islands Harbor, CA. (a) A line drawn from Channel Islands Harbor South Jetty Light 2 to Channel Islands Harbor Breakwater... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Channel Islands Harbor, CA. 80...
33 CFR 110.250 - St. Thomas Harbor, Charlotte Amalie, V.I.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false St. Thomas Harbor, Charlotte... SECURITY ANCHORAGES ANCHORAGE REGULATIONS Anchorage Grounds § 110.250 St. Thomas Harbor, Charlotte Amalie... move promptly upon notification by the Harbor Master. (4) The harbor regulations for the Port of St...
Xu, Ming; Zhu, Jianqiang; Wang, Fanfan; Xiong, Yunjing; Wu, Yakun; Wang, Qiuquan; Weng, Jian; Zhang, Zhihong; Chen, Wei; Liu, Sijin
2016-03-22
The unique physicochemical properties of two-dimensional (2D) graphene oxide (GO) could greatly benefit the biomedical field; however, recent research demonstrated that GO could induce in vitro and in vivo toxicity. We determined the mechanism of GO induced toxicity, and our in vitro experiments revealed that pristine GO could impair cell membrane integrity and functions including regulation of membrane- and cytoskeleton-associated genes, membrane permeability, fluidity and ion channels. Furthermore, GO induced platelet depletion, pro-inflammatory response and pathological changes of lung and liver in mice. To improve the biocompatibility of pristine GO, we prepared a series of GO derivatives including aminated GO (GO-NH2), poly(acrylamide)-functionalized GO (GO-PAM), poly(acrylic acid)-functionalized GO (GO-PAA) and poly(ethylene glycol)-functionalized GO (GO-PEG), and compared their toxicity with pristine GO in vitro and in vivo. Among these GO derivatives, GO-PEG and GO-PAA induced less toxicity than pristine GO, and GO-PAA was the most biocompatible one in vitro and in vivo. The differences in biocompatibility were due to the differential compositions of protein corona, especially immunoglobulin G (IgG), formed on their surfaces that determine their cell membrane interaction and cellular uptake, the extent of platelet depletion in blood, thrombus formation under short-term exposure and the pro-inflammatory effects under long-term exposure. Overall, our combined data delineated the key molecular mechanisms underlying the in vivo and in vitro biological behaviors and toxicity of pristine GO, and identified a safer GO derivative that could be used for future applications.
Park, Sunghoon; Kim, Soohyun; Park, Suyoung; Lee, Wan In; Lee, Chongmu
2014-01-01
This study compared the responses of Pd-functionalized and pristine titanate (TiO2) nanotube arrays to ethanol with those to acetone to determine the effects of functionalization of TiO2 nanotubes with Pd nanoparticles on the sensitivity and selectivity. The responses of pristine and Pd-functionalized TiO2 nanotube arrays to ethanol gas at 200 °C were ∼2877% and ∼21,253%, respectively. On the other hand, the responses of pristine and Pd-functionalized TiO2 nanotube arrays to acetone gas at 250 °C were ∼1636% and 8746% respectively. In the case of ethanol sensing, the response and recovery times of Pd-functionalized TiO2 nanotubes (10.2 and 7.1 s) were obviously shorter than those of pristine TiO2 nanotubes (14.3 and 8.8 s), respectively. In contrast, in the case of acetone sensing the response and recovery times of Pd-functionalized TiO2 nanotubes (42.5 and 19.7 s) were almost the same as those of pristine TiO2 nanotubes (47.2 and 17.9 s). TiO2 nanotube arrays showed the strongest response to ethanol and Pd functionalization was the most effective in improving the response of TiO2 nanotubes to ethanol among six different types of gases: ethanol, acetone, CO, H2, NH3 and NO2. The origin of the superior sensing properties of Pd-functionalized TiO2 nanotubes toward ethanol to acetone is also discussed. PMID:25166499
Alonso-Hernandez, C M; Mesa-Albernas, M; Tolosa, I
2014-01-01
The spatial distribution of various organochlorinated compounds, e.g. PCBs, DDTs, HCB and HCHs, were investigated in sediments of the Gulf of Batabanó, Cuba. Among the target organochlorine compounds measured, ΣDDT isomers were the predominant contaminant with concentrations ranging from 0.019 to 1.27 ng g(-1)dry wt. Lindane was present at very low concentrations in the range n.d. to 0.05 ng g(-1), while PCBs and other organochlorine pesticide residues, such as HCB, Heptaclor, Aldrin and Mirex were lower than detection limits (∼0.010 ng g(-1)). According to established sediment quality guidelines, the OCPs concentrations encountered in the surface sediments are probably not having an adverse effect on sediment dwelling organisms. Compared to concentrations reported in coastal environments from other parts of the world, PCBs and OCs concentrations in surface sediments of Batabanó Gulf were low and similar to the reported for remote and pristine environments. These results contribute to the sparse regional database for organochlorinated compounds in the Caribbean marine environment. Copyright © 2013. Published by Elsevier Ltd.
Tapilatu, Yosmina H; Grossi, Vincent; Acquaviva, Monique; Militon, Cécile; Bertrand, Jean-Claude; Cuny, Philippe
2010-03-01
Little information exists about the ability of halophilic archaea present in hypersaline environments to degrade hydrocarbons. In order to identify the potential actors of hydrocarbon degradation in these environments, enrichment cultures were prepared using samples collected from a shallow crystallizer pond with no known contamination history in Camargue, France, with n-alkanes provided as source of carbon and energy. Five alkane-degrading halophilic archaeal strains were isolated: one (strain MSNC 2) was closely related to Haloarcula and three (strains MSNC 4, MSNC 14, and MSNC 16) to Haloferax. Biodegradation assays showed that depending on the strain, 32 to 95% (0.5 g/l) of heptadecane was degraded after 30 days of incubation at 40 degrees C in 225 g/l NaCl artificial medium. One of the strains (MSNC 14) was also able to degrade phenanthrene. This work clearly shows for the first time the potential role of halophilic archaea belonging to the genera Haloarcula and Haloferax in the degradation of hydrocarbons in both pristine and hydrocarbon-contaminated hypersaline environments.
NASA Astrophysics Data System (ADS)
Siegert, Martin J.; Clarke, Rachel J.; Mowlem, Matt; Ross, Neil; Hill, Christopher S.; Tait, Andrew; Hodgson, Dominic; Parnell, John; Tranter, Martyn; Pearce, David; Bentley, Michael J.; Cockell, Charles; Tsaloglou, Maria-Nefeli; Smith, Andy; Woodward, John; Brito, Mario P.; Waugh, Ed
2012-01-01
Antarctic subglacial lakes are thought to be extreme habitats for microbial life and may contain important records of ice sheet history and climate change within their lake floor sediments. To find whether or not this is true, and to answer the science questions that would follow, direct measurement and sampling of these environments are required. Ever since the water depth of Vostok Subglacial Lake was shown to be >500 m, attention has been given to how these unique, ancient, and pristine environments may be entered without contamination and adverse disturbance. Several organizations have offered guidelines on the desirable cleanliness and sterility requirements for direct sampling experiments, including the U.S. National Academy of Sciences and the Scientific Committee on Antarctic Research. Here we summarize the scientific protocols and methods being developed for the exploration of Ellsworth Subglacial Lake in West Antarctica, planned for 2012-2013, which we offer as a guide to future subglacial environment research missions. The proposed exploration involves accessing the lake using a hot-water drill and deploying a sampling probe and sediment corer to allow sample collection. We focus here on how this can be undertaken with minimal environmental impact while maximizing scientific return without compromising the environment for future experiments.
Flexible Graphene Composites for Human Space Flight Applications
NASA Technical Reports Server (NTRS)
Sosa, Edward D.
2013-01-01
Graphene oxide allows for better dispersion stability in aqueous and organic solvents. Stabilizers provide dispersion of pristine graphene. Roll coating provide the best coverage of polyurethane sheets. Graphene and GO coated polyurethane used to fabricate flexible laminate composite. Permeation testing indicates that pristine graphene acts as a better gas barrier material. Continuous graphene films are expected to provide even better gas barrier properties.
Rapid soil development after windthrow disturbance in pristine forests.
B.T. Bormann; H. Spaltenstein; M.H. McClellan; F.C. Ugolini; K. Cromack; S.M. Nay
1995-01-01
1. We examined how rapidly soils can change during secondary succession by observing soil development on 350-year chronosequences in three pristine forest ecosystems in south-east Alaska. 2. Soil surfaces, created by different windthrow events of known or estimated age, were examined within each of three forest stands (0.5-2.0 ha plots; i.e. a within-stand...
Modified Single-Wall Carbon Nanotubes for Reinforce Thermoplastic Polyimide
NASA Technical Reports Server (NTRS)
Lebron-COlon, Marisabel; Meador, Michael A.
2006-01-01
A significant improvement in the mechanical properties of the thermoplastic polyimide film was obtained by the addition of noncovalently functionalized single-wall carbon nanotubes (SWNTs). Polyimide films were reinforced using pristine SWNTs and functionalized SWNTs (F-SWNTs). The tensile strengths of the polyimide films containing F-SWNTs were found to be approximately 1.4 times higher than those prepared from pristine SWNTs.
Tang, Xiao-Yan; Huang, Wen-Da; Guo, Jing-Jing; Yang, Yang; Tao, Ran; Feng, Xu
2017-07-05
Fe-impregnated biochar was assessed as a method to remove the pesticide pollutant chlorpyrifos, utilizing biochar/FeO x composite synthesized via chemical coprecipitation of Fe 3+ /Fe 2+ onto Cyperus alternifolius biochar. Fe-impregnated biochar exhibited a higher sorption capacity than pristine biochar, resulting in more efficient removal of chlorpyrifos from water. Soil was dosed with pristine or Fe-impregnated biochar at 0.1 or 1.0% w/w, to evaluate chlorpyrifos uptake in Allium fistulosum L. (Welsh onion). The results showed that the average concentration of chlorpyrifos and its degradation product, 3,5,6-trichloro-2-pyridinol (TCP), decreased in A. fistulosum L. with increased levels of pristine biochar and Fe-biochar. Fe-biochar was found to be more effective in reducing the uptake of chlorpyrifos by improving the sorption ability and increasing plant root iron plaque. Bioavailability of chlorpyrifos is reduced with both biochar and Fe-biochar soil dosing; however, the greatest persistence of chlorpyrifos residues was observed with 1.0% pristine biochar. Microbial community analysis showed Fe-biochar to have a positive impact on the efficiency of chlorpyrifos degradation in soils, possibly by altering microbial communities.
Zhou, Lulu; Forman, Henry Jay; Ge, Yi; Lunec, Joseph
2017-08-01
Chemical functionalization broadens carbon nanotube (CNT) applications, conferring new functions, but at the same time potentially altering toxicity. Although considerable experimental data related to CNT toxicity, at the molecular and cellular levels, have been reported, there is very limited information available for the corresponding mechanism involved (e.g. cell apoptosis and genotoxicity). The threshold dose for safe medical application in relation to both pristine and functionalized carbon nanotubes remains ambiguous. In this study, we evaluated the in vitro cytotoxicity of pristine and functionalized (OH, COOH) multi-walled carbon nanotubes (MWCNTs) for cell viability, oxidant detection, apoptosis and DNA mutations, to determine the non-toxic dose and influence of functional group in a human lung-cancer cell line exposed to 1-1000μg/ml MWCNTs for 24, 48 and 72h. The findings suggest that pristine MWCNTs induced more cell death than functionalized MWCNTs while functionalized MWCNTs are more genotoxic compared to their pristine form. The level of both dose and dispersion in the matrix used should be taken into consideration before applying further clinical applications of MWCNTs. Copyright © 2017 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Singha, Somdutta; Ghosh, Swapankumar
2017-09-01
Carbon nanotubes in all forms are very much insoluble in both organic and inorganic solvents due to its high agglomeration and entangled morphology. General methods for dissolution of single-walled carbon nanotubes (SWNTs) are mostly associated with complexation or polymerization or addition of macromolecules which change the physical or chemical properties of SWNTs and the pristine nature of SWNTs is lost. Dissolution of SWNTs in a solvent like aniline is practiced here which is a very simple reaction method. Here aniline is capable to form a SWNT-aniline charge transfer complex without attachment of macromolecules or polymer which is also soluble in other organic solvents. Solvation of SWNTs by this method is also capable of maintaining the similarity between the structure of SWNTs before and after the dissolution, which means that the pristine nature of SWNTs is preserved. Formation of charge transfer complex in this reaction has been proven by UV-Vis/NIR absorption and photoluminescence spectroscopy. Raman spectroscopy and electron microscopy (FESEM and TEM) are the evidences for protection of the pristine nature of SWNTs even after high-temperature complexation reaction with aniline and also after solubilization in organic solvents.
Health impairments arising from drinking water resources contaminated with Vibrio cholerae.
Ramamurthy, T; Chakraborty, S; Nair, G B; Bhattacharya, S K
2000-01-01
The endemic and seasonal nature of cholera depends upon the survival of toxigenic Vibrio cholerae in various niches of the aquatic environment. To understand the transmission and ecology of V. cholerae, it is necessary to know which component in the aquatic ecosystem can harbor it and thus contribute to the endemic presence. Toxigenic V. cholerae is now recognized as an autochthonous member of the microflora in many aquatic environments based on its protracted survival and proliferation without losing the virulence determinants. This article summarizes knowledge about the ecology, survival strategies and elimination techniques of V. cholerae from natural waters with special reference to drinking water.
33 CFR 100.109 - Winter Harbor Lobster Boat Race, Winter Harbor, ME.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Winter Harbor Lobster Boat Race, Winter Harbor, ME. 100.109 Section 100.109 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF... Lobster Boat Race, Winter Harbor, ME. (a) Regulated area. The regulated area includes all waters of Winter...
NASA Technical Reports Server (NTRS)
Neal, Clive R.; Taylor, Lawrence A.
1991-01-01
The criteria and clues for identifying meteorite contamination are outlined to aid in the quest for more knowledge regarding the evolution of the Moon and the early Earth. The Warren and Wasson seven criteria for establishing the pristine nature of highland rocks are presented. Other topics covered include iron/nickel metals, monomict nature, and lunar glasses. The major conclusion is that pristinity should not be the primary consideration in the study of lunar rocks. The most important criterion to establish is whether or not the lunar sample contains more than one lunar rock type. Even if a sample is non-pristine, as long as only one lunar rock type is present, petrogenetic interpretation can still be carried out.
NASA Astrophysics Data System (ADS)
Page, Alister J.; Chandrakumar, K. R. S.; Irle, Stephan; Morokuma, Keiji
2011-05-01
Quantum chemical molecular dynamics (QM/MD) simulations of pristine and carbon-doped SiO 2 nanoparticles have been performed between 1000 and 3000 K. At temperatures above 1600 K, pristine nanoparticle SiO 2 decomposes rapidly, primarily forming SiO. Similarly, carbon-doped nanoparticle SiO 2 decomposes at temperatures above 2000 K, primarily forming SiO and CO. Analysis of the physical states of these pristine and carbon-doped SiO 2 nanoparticles indicate that they remain in the solid phase throughout decomposition. This process is therefore one of sublimation, as the liquid phase is never entered. Ramifications of these observations with respect to presently debated mechanisms of carbon nanotube growth on SiO 2 nanoparticles will be discussed.
The study of electronic structure and properties of silicene for gas sensor application
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wella, Sasfan A.; Syaputra, Marhamni; Wungu, Triati D. K., E-mail: triati@fi.itb.ac.id
2016-03-11
In this study, we investigated the adsorption of gas molecules (H{sub 2}S, CO) on pristine silicene using first principles calculation. The structure, electronic properties, and adsorption energy of H{sub 2}S,CO/silicene are discussed thoroughly. We found that the pristine silicenewith low buckling structure is the most stable as compared with planar and high buckling structures. Silicene was able to detect a gas molecule which can be observed according tothe density of states analysis. Though a gas molecule adsorbed weakly, the electronic properties of the low buckling pristine silicene changed from semi-metal (zero band gap) to semiconductor. The adsorption energy of H{submore » 2}S and CO on silicene is 0.075 eV and 0.06 eV, respectively.« less
Fe local structure in Pt-free nitrogen-modified carbon based electrocatalysts: XAFS study
NASA Astrophysics Data System (ADS)
Witkowska, Agnieszka; Giuli, Gabriele; Renzi, Marco; Marzorati, Stefania; Yiming, Wubulikasimu; Nobili, Francesco; Longhi, Mariangela
2016-05-01
The paper presents a new results on the bonding environment (coordination number and geometry) and on oxidation states of Fe in nitrogen-modified Fe/C composites used as Pt-free catalysts for oxygen reduction in Direct Hydrogen Fuel Cells. Starting from glucose or fructose, two catalysts displaying different electrochemical performance were prepared and studied in the form of pristine powder and thin catalytic layer of electrode by Fe K-edge XAFS spectroscopy. The results show how the Fe local structure varies as a function of different synthesis conditions and how changes in the structural properties of the catalysts are related to fuel cell electrochemical performance increase during a cell activation period.
Environmental exposures to agrochemicals in the Sierra Nevada mountain range
LeNoir, J.; Aston, L.; Data, S.; Fellers, G.; McConnell, L.; Sieber, J.
2000-01-01
The release of pesticides into the environment may impact human and environmental health. Despite the need for environmental exposure data, few studies quantify exposures in urban areas and even fewer determine exposures to wildlife in remote areas. Although it is expected that concentrations in remote regions will be low, recent studies suggest that even low concentrations may have deleterious effects on wildlife. Many pesticides are known to interfere with the endocrine systems of humans and wildlife, adversely affecting growth, development, and behavior. This chapter reviews the fate and transport of pesticides applied in the Central Valley of California and quantifies their subsequent deposition into the relatively pristine Sierra Nevada Mountain Range.
Weiss, Lawrence A.; Sears, Michael P.; Cervione, Michael A.
1994-01-01
Effects of urbanization have increased the frequency and size of floods along certain reaches of Harbor Brook and Crow Hollow Brook in Meriden, Conn. A floodprofile-modeling study was conducted to model the effects of selected channel and structural modifications on flood elevations and inundated areas. The study covered the reach of Harbor Brook downstream from Interstate 691 and the reach of Crow Hollow Brook downstream from Johnson Avenue. Proposed modifications, which include changes to bank heights, channel geometry, structural geometry, and streambed armoring on Harbor Brook and changes to bank heights on Crow Hollow Brook, significantly lower flood elevations. Results of the modeling indicate a significant reduction of flood elevations for the 10-year, 25-year, 35-year, 50-year, and 100-year flood frequencies using proposed modifications to (1 ) bank heights between Harbor Brook Towers and Interstate 691 on Harbor Brook, and between Centennial Avenue and Johnson Avenue on Crow Hollow Brook; (2) channel geometry between Coe Avenue and Interstate 69 1 on Harbor Brook; (3) bridge and culvert opening geometry between Harbor Brook Towers and Interstate 691 on Harbor Brook; and (4) channel streambed armoring between Harbor Brook Towers and Interstate 691 on Harbor Brook. The proposed modifications were developed without consideration of cost-benefit ratios.
33 CFR 165.904 - Lake Michigan at Chicago Harbor & Burnham Park Harbor-Safety and Security Zone.
Code of Federal Regulations, 2010 CFR
2010-07-01
... Harbor, to the northwest point. (b) Effective times and dates. This safety and security zone will be in... & Burnham Park Harbor-Safety and Security Zone. 165.904 Section 165.904 Navigation and Navigable Waters... Guard District § 165.904 Lake Michigan at Chicago Harbor & Burnham Park Harbor—Safety and Security Zone...
Tech Talk for Social Studies Teachers Lest We Forget: Remembering Pearl Harbor.
ERIC Educational Resources Information Center
Green, Tim
2001-01-01
Presents an annotated bibliography that provides Web sites about Pearl Harbor (Hawaii). Includes Web sites that cover Pearl Harbor history, a live view of Pearl Harbor, stories from people who remember where they were during the attack, information on the naval station at Pearl Harbor, and a virtual tour of the USS Arizona. (CMK)
Ballmann, Anne E; Torkelson, Miranda R; Bohuski, Elizabeth A; Russell, Robin E; Blehert, David S
2017-10-01
Bats occupying hibernacula during summer are exposed to Pseudogymnoascus destructans (Pd), the causative agent of white-nose syndrome (WNS), and may contribute to its dispersal. Furthermore, equipment and clothing exposed to cave environments are a potential source for human-assisted spread of Pd. To explore dispersal hazards for Pd during the nonhibernal season, we tested samples that were collected from bats, the environment, and equipment at hibernacula in the eastern US between 18 July-22 August 2012. Study sites included six hibernacula known to harbor bats with Pd with varying winter-count impacts from WNS and two hibernacula (control sites) without prior history of WNS. Nucleic acid from Pd was detected from wing-skin swabs or guano from 40 of 617 bats (7% prevalence), including males and females of five species at five sites where WNS had previously been confirmed as well as from one control site. Analysis of guano collected during summer demonstrated a higher apparent prevalence of Pd among bats (17%, 37/223) than did analysis of wing-skin swabs (1%, 4/617). Viable Pd cultured from wing skin (2%, 1/56) and low recapture rates at all sites suggested bats harboring Pd during summer could contribute to pathogen dispersal. Additionally, Pd DNA was detected on clothing and trapping equipment used inside and near hibernacula, and Pd was detected in sediment more readily than in swabs of hibernaculum walls. Statistically significant differences in environmental abundance of Pd were not detected among sites, but prevalence of Pd differed between sites and among bat species. Overall, bats using hibernacula in summer can harbor Pd on their skin and in their guano, and demonstration of Pd on clothing, traps, and other equipment used at hibernacula during summertime within the WNS-affected region indicates risk for pathogen dispersal during the nonhibernal season.
Curtis-Robles, Rachel; Snowden, Karen F; Dominguez, Brandon; Dinges, Lewis; Rodgers, Sandy; Mays, Glennon; Hamer, Sarah A
2017-01-01
Trypanosoma cruzi is the etiologic agent of Chagas disease throughout the Americas. Few population-level studies have examined the epidemiology of canine infection and strain types of T. cruzi that infect canines in the USA. We conducted a cross-sectional study of T. cruzi infection in working hound dogs in south central Texas, including analysis of triatomine vectors collected within kennel environments. Paired IFA and Chagas Stat-Pak serological testing showed an overall seroprevalence of 57.6% (n = 85), with significant variation across kennels. Dog age had a marginally significant effect on seropositivity, with one year of age increase associated with a 19.6% increase in odds of being seropositive (odds ratio 95% CI 0.996-1.435; p = 0.055). PCR analyses of blood revealed 17.4% of dogs harbored parasite DNA in their blood, including both seronegative and seropositive dogs. Molecular screening of organs from opportunistically sampled seropositive dogs revealed parasite DNA in heart, uterus, and mammary tissues. Strain-typing showed parasite discrete typing units (DTU) TcI and TcIV present in dog samples, including a co-occurrence of both DTUs in two individual dogs. Bloodmeal analysis of Triatoma gerstaeckeri and Triatoma sanguisuga insects collected from the kennels revealed exclusively dog DNA. Vector infection with T. cruzi was 80.6% (n = 36), in which T. gerstaeckeri disproportionately harbored TcI (p = 0.045) and T. sanguisuga disproportionately harbored TcIV (p = 0.029). Tracing infection status across dog litters showed some seropositive offspring of seronegative dams, suggesting infection of pups from local triatomine vectors rather than congenital transmission. Canine kennels are high-risk environments for T. cruzi transmission, in which dogs likely serve as the predominant parasite reservoir. Disease and death of working dogs from Chagas disease is associated with unmeasured yet undoubtedly significant financial consequences because working dogs are highly trained and highly valued.
Evaluation method for the potential functionome harbored in the genome and metagenome
2012-01-01
Background One of the main goals of genomic analysis is to elucidate the comprehensive functions (functionome) in individual organisms or a whole community in various environments. However, a standard evaluation method for discerning the functional potentials harbored within the genome or metagenome has not yet been established. We have developed a new evaluation method for the potential functionome, based on the completion ratio of Kyoto Encyclopedia of Genes and Genomes (KEGG) functional modules. Results Distribution of the completion ratio of the KEGG functional modules in 768 prokaryotic species varied greatly with the kind of module, and all modules primarily fell into 4 patterns (universal, restricted, diversified and non-prokaryotic modules), indicating the universal and unique nature of each module, and also the versatility of the KEGG Orthology (KO) identifiers mapped to each one. The module completion ratio in 8 phenotypically different bacilli revealed that some modules were shared only in phenotypically similar species. Metagenomes of human gut microbiomes from 13 healthy individuals previously determined by the Sanger method were analyzed based on the module completion ratio. Results led to new discoveries in the nutritional preferences of gut microbes, believed to be one of the mutualistic representations of gut microbiomes to avoid nutritional competition with the host. Conclusions The method developed in this study could characterize the functionome harbored in genomes and metagenomes. As this method also provided taxonomical information from KEGG modules as well as the gene hosts constructing the modules, interpretation of completion profiles was simplified and we could identify the complementarity between biochemical functions in human hosts and the nutritional preferences in human gut microbiomes. Thus, our method has the potential to be a powerful tool for comparative functional analysis in genomics and metagenomics, able to target unknown environments containing various uncultivable microbes within unidentified phyla. PMID:23234305
Curtis-Robles, Rachel; Snowden, Karen F.; Dominguez, Brandon; Dinges, Lewis; Rodgers, Sandy; Mays, Glennon
2017-01-01
Background Trypanosoma cruzi is the etiologic agent of Chagas disease throughout the Americas. Few population-level studies have examined the epidemiology of canine infection and strain types of T. cruzi that infect canines in the USA. We conducted a cross-sectional study of T. cruzi infection in working hound dogs in south central Texas, including analysis of triatomine vectors collected within kennel environments. Methodology/Principle Findings Paired IFA and Chagas Stat-Pak serological testing showed an overall seroprevalence of 57.6% (n = 85), with significant variation across kennels. Dog age had a marginally significant effect on seropositivity, with one year of age increase associated with a 19.6% increase in odds of being seropositive (odds ratio 95% CI 0.996–1.435; p = 0.055). PCR analyses of blood revealed 17.4% of dogs harbored parasite DNA in their blood, including both seronegative and seropositive dogs. Molecular screening of organs from opportunistically sampled seropositive dogs revealed parasite DNA in heart, uterus, and mammary tissues. Strain-typing showed parasite discrete typing units (DTU) TcI and TcIV present in dog samples, including a co-occurrence of both DTUs in two individual dogs. Bloodmeal analysis of Triatoma gerstaeckeri and Triatoma sanguisuga insects collected from the kennels revealed exclusively dog DNA. Vector infection with T. cruzi was 80.6% (n = 36), in which T. gerstaeckeri disproportionately harbored TcI (p = 0.045) and T. sanguisuga disproportionately harbored TcIV (p = 0.029). Tracing infection status across dog litters showed some seropositive offspring of seronegative dams, suggesting infection of pups from local triatomine vectors rather than congenital transmission. Conclusions/Significance Canine kennels are high-risk environments for T. cruzi transmission, in which dogs likely serve as the predominant parasite reservoir. Disease and death of working dogs from Chagas disease is associated with unmeasured yet undoubtedly significant financial consequences because working dogs are highly trained and highly valued. PMID:28095511
Ballmann, Anne; Torkelson, Miranda R.; Bohuski, Elizabeth A.; Russell, Robin E.; Blehert, David
2017-01-01
Bats occupying hibernacula during summer are exposed to Pseudogymnoascus destructans (Pd), the causative agent of white-nose syndrome (WNS), and may contribute to its dispersal. Furthermore, equipment and clothing exposed to cave environments are a potential source for human-assisted spread of Pd. To explore dispersal hazards for Pd during the nonhibernal season, we tested samples that were collected from bats, the environment, and equipment at hibernacula in the eastern US between 18 July–22 August 2012. Study sites included six hibernacula known to harbor bats with Pd with varying winter-count impacts from WNS and two hibernacula (control sites) without prior history of WNS. Nucleic acid from Pd was detected from wing-skin swabs or guano from 40 of 617 bats (7% prevalence), including males and females of five species at five sites where WNS had previously been confirmed as well as from one control site. Analysis of guano collected during summer demonstrated a higher apparent prevalence of Pd among bats (17%, 37/223) than did analysis of wing-skin swabs (1%, 4/617). Viable Pd cultured from wing skin (2%, 1/56) and low recapture rates at all sites suggested bats harboring Pd during summer could contribute to pathogen dispersal. Additionally, Pd DNA was detected on clothing and trapping equipment used inside and near hibernacula, and Pd was detected in sediment more readily than in swabs of hibernaculum walls. Statistically significant differences in environmental abundance of Pd were not detected among sites, but prevalence of Pd differed between sites and among bat species. Overall, bats using hibernacula in summer can harbor Pd on their skin and in their guano, and demonstration of Pd on clothing, traps, and other equipment used at hibernacula during summertime within the WNS-affected region indicates risk for pathogen dispersal during the nonhibernal season.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chou, C.L.; Uthe, J.F.
1995-01-01
Only a few studies have concentrated on elements such as thallium (TI). Uranium (U) has been studied as a radionuclide of concern in food and the environment. Foodstuffs contain 10-100 ng U{center_dot}{sup -1} with vegetables and cereals contributing most heavily to the daily intake of ca 1.5 ug U. Between 10-30% of ingested U is absorbed, with most being stored in bone. Rainbow trout (onchorynchus mykiss) and longnose sucker (Catostomus catostomus) from a lake with naturally high radioactivity contained < 5 ng U{center_dot}g{sup -1} in the flesh. Trout bone contained 40 ng U{center_dot}g{sup -1}. Higher tissue U concentrations occurred inmore » fish from areas receiving U mining wastes. Bioconcentration factors for bone and flesh were estimated to be low, 118 and 14.7, respectively. This paper describes the Inductively coupled plasma-mass spectrometry (ICP-MS) determination of Tl and U in digestive gland tissue from lobsters captured in the vicinity of Belledune Harbor, New Brunswick, Canada. The harbor is the site of a lead smelter, a fertilizer plant, and a coal-fired power station (the latter due to enter production in late 1993) and thus has the potential of adding significant amounts of Tl to the local marine environment. The accumulation of Tl from water by marine shellfish is low, at least for bivalves, and the accumulated Tl is eliminated in a number of days when the animals are transferred to clean water. Bioconcentration factors for U in finfish ranged from 0.4-17 for larger species. However, because of the high concentrations of various trace elements in lobster digestive gland, its desirability as a foodstuff, and its relatively large size (approximately 20% of the edible tissue yield), we have investigated Tl and U concentrations and {sup 235U}/{sup 238U} ratios in it. 15 refs., 1 fig., 3 tabs.« less
Shi, Liyu; Weng, Jianfeng; Liu, Changlin; Song, Xinyuan; Miao, Hongqin; Hao, Zhuanfang; Xie, Chuanxiao; Li, Mingshun; Zhang, Degui; Bai, Li; Pan, Guangtang; Li, Xinhai; Zhang, Shihuang
2013-04-01
Maize rough dwarf disease (MRDD, a viral disease) results in significant grain yield losses, while genetic basis of which is largely unknown. Based on comparative genomics, eukaryotic translation initiation factor 4E (eIF4E) was considered as a candidate gene for MRDD resistance, validation of which will help to understand the possible genetic mechanism of this disease. ZmeIF4E (orthologs of eIF4E gene in maize) encodes a protein of 218 amino acids, harboring five exons and no variation in the cDNA sequence is identified between the resistant inbred line, X178 and susceptible one, Ye478. ZmeIF4E expression was different in the two lines plants treated with three plant hormones, ethylene, salicylic acid, and jasmonates at V3 developmental stage, suggesting that ZmeIF4E is more likely to be involved in the regulation of defense gene expression and induction of local and systemic resistance. Moreover, four cis-acting elements related to plant defense responses, including DOFCOREZM, EECCRCAH1, GT1GAMSCAM4, and GT1CONSENSUS were detected in ZmeIF4E promoter for harboring sequence variation in the two lines. Association analysis with 163 inbred lines revealed that one SNP in EECCRCAH1 is significantly associated with CSI of MRDD in two environments, which explained 3.33 and 9.04 % of phenotypic variation, respectively. Meanwhile, one SNP in GT-1 motif was found to affect MRDD resistance only in one of the two environments, which explained 5.17 % of phenotypic variation. Collectively, regulatory motifs respectively harboring the two significant SNPs in ZmeIF4E promoter could be involved in the defense process of maize after viral infection. These results contribute to understand maize defense mechanisms against maize rough dwarf virus.
2010-06-01
173 Figure 68. MATLAB "inpolygon" function depiction....................................................174...Kollmorgen AN/BVS-1 photonic mast. The sensors mounted on this mast include LLTV (low-light TV), thermal imager and laser rangefinder. To facilitate...Robert Tillson, SeeCoast Port Surveillance, Proceedings of SPIE Vol. 6204: Photonics for Port and Harbor Security II Orlando, FL, April 18–19, 2006. 70
Environmental cleaning and disinfection of patient areas.
Doll, Michelle; Stevens, Michael; Bearman, Gonzalo
2018-02-01
The healthcare setting is predisposed to harbor potential pathogens, which in turn can pose a great risk to patients. Routine cleaning of the patient environment is critical to reduce the risk of hospital-acquired infections. While many approaches to environmental cleaning exist, manual cleaning supplemented with ongoing assessment and feedback may be the most feasible for healthcare facilities with limited resources. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.
2015-09-30
Landing Marine Laboratories 8272 Moss Landing Rd. Moss Landing, CA, 95039 USA phone: (831) 771-4417 email: gmcdonald@mlml.calstate.edu Award...Number: N000141410416 http://www.marinebioacoustics.com LONG-TERM GOALS Marine mammals face potentially dramatic changes in the environment...as well as continued disturbances of their ocean habitat from shipping, sonar, fisheries , oil exploration and other ocean activities. To predict
33 CFR 162.155 - Sandusky and Huron Harbors, Ohio.
Code of Federal Regulations, 2011 CFR
2011-07-01
... Harbors, Ohio. (a) In Sandusky Harbor, no vessel greater than 40 feet in length may exceed 10 miles per hour. (b) In Huron Harbor, no vessel greater than 40 feet in length may exceed 6 miles per hour, except in the outer harbor where no vessel greater than 40 feet in length may exceed 10 miles per hour. Note...
33 CFR 162.155 - Sandusky and Huron Harbors, Ohio.
Code of Federal Regulations, 2014 CFR
2014-07-01
... Harbors, Ohio. (a) In Sandusky Harbor, no vessel greater than 40 feet in length may exceed 10 miles per hour. (b) In Huron Harbor, no vessel greater than 40 feet in length may exceed 6 miles per hour, except in the outer harbor where no vessel greater than 40 feet in length may exceed 10 miles per hour. Note...
33 CFR 162.155 - Sandusky and Huron Harbors, Ohio.
Code of Federal Regulations, 2013 CFR
2013-07-01
... Harbors, Ohio. (a) In Sandusky Harbor, no vessel greater than 40 feet in length may exceed 10 miles per hour. (b) In Huron Harbor, no vessel greater than 40 feet in length may exceed 6 miles per hour, except in the outer harbor where no vessel greater than 40 feet in length may exceed 10 miles per hour. Note...
33 CFR 162.155 - Sandusky and Huron Harbors, Ohio.
Code of Federal Regulations, 2010 CFR
2010-07-01
... Harbors, Ohio. (a) In Sandusky Harbor, no vessel greater than 40 feet in length may exceed 10 miles per hour. (b) In Huron Harbor, no vessel greater than 40 feet in length may exceed 6 miles per hour, except in the outer harbor where no vessel greater than 40 feet in length may exceed 10 miles per hour. Note...
33 CFR 162.155 - Sandusky and Huron Harbors, Ohio.
Code of Federal Regulations, 2012 CFR
2012-07-01
... Harbors, Ohio. (a) In Sandusky Harbor, no vessel greater than 40 feet in length may exceed 10 miles per hour. (b) In Huron Harbor, no vessel greater than 40 feet in length may exceed 6 miles per hour, except in the outer harbor where no vessel greater than 40 feet in length may exceed 10 miles per hour. Note...
Code of Federal Regulations, 2010 CFR
2010-07-01
... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false St. Lawrence River, Cape Vincent Harbor, N.Y.; use, administration, and navigation of the harbor and U.S. breakwater. 207.610 Section 207... NAVIGATION REGULATIONS § 207.610 St. Lawrence River, Cape Vincent Harbor, N.Y.; use, administration, and...
Sites throughout Boston Harbor were analyzed for caffeine to assess its utility as a tracer in identifying sources of sanitary wastewater. Caffeine ranged from 15 ng/L in the outer harbor to a high of 185 ng/L in the inner harbor. Inner harbor concentrations were a result of comb...
Cebrian, Emma; Uriz, Maria Jesus; Garrabou, Joaquim; Ballesteros, Enric
2011-01-01
Mass mortality events are increasing dramatically in all coastal marine environments. Determining the underlying causes of mass mortality events has proven difficult in the past because of the lack of prior quantitative data on populations and environmental variables. Four-year surveys of two shallow-water sponge species, Ircinia fasciculata and Sarcotragus spinosulum, were carried out in the western Mediterranean Sea. These surveys provided evidence of two severe sponge die-offs (total mortality ranging from 80 to 95% of specimens) occurring in the summers of 2008 and 2009. These events primarily affected I. fasciculata, which hosts both phototrophic and heterotrophic microsymbionts, while they did not affect S. spinosulum, which harbors only heterotrophic bacteria. We observed a significant positive correlation between the percentage of injured I. fasciculata specimens and exposure time to elevated temperature conditions in all populations, suggesting a key role of temperature in triggering mortality events. A comparative ultrastructural study of injured and healthy I. fasciculata specimens showed that cyanobacteria disappeared from injured specimens, which suggests that cyanobacterial decay could be involved in I. fasciculata mortality. A laboratory experiment confirmed that the cyanobacteria harbored by I. fasciculata displayed a significant reduction in photosynthetic efficiency in the highest temperature treatment. The sponge disease reported here led to a severe decrease in the abundance of the surveyed populations. It represents one of the most dramatic mass mortality events to date in the Mediterranean Sea.
Gonzalez, Armando E; López-Urbina, Teresa; Tsang, Byron Y; Gavidia, César M; Garcia, Héctor H; Silva, María E; Ramos, Daphne D; Manzanedo, Rafael; Sánchez-Hidalgo, Lelia; Gilman, Robert H; Tsang, Victor C W
2005-09-01
Taenia solium taeniasis/cysticercosis is one of few potentially eradicable infectious diseases and is the target of control programs in several countries. The larval stage of this zoonotic cestode invades the human brain and is responsible for most cases of adult-onset epilepsy in the world. The pig is the natural intermediate host, harboring the larvae or cysticerci. Our current understanding of the life cycle implicates humans as the only definitive host and tapeworm carrier (developing taeniasis) and thus the sole source of infective eggs that are responsible for cysticercosis in both human and pigs through oral-fecal transmission. Here we show evidence of an alternative pig-to-pig route of transmission, previously not suspected to exist. In a series of four experiments, naive sentinel pigs were exposed to pigs that had been infected orally with tapeworm segments (containing infective eggs) and moved to a clean environment. Consistently in all four experiments, at least one of the sentinel pigs became seropositive or infected with parasite cysts with much lower cyst burdens than did primarily infected animals. Second-hand transmission of Taenia solium eggs could explain the overdispersed pattern of porcine cysticercosis, with few pigs harboring heavy parasite burdens and many more harboring small numbers of parasites. This route of transmission opens new avenues for consideration with respect to control strategies.
Grace Under Fire: The Army Nurses of Pearl Harbor, 1941.
Milbrath, Gwyneth R
2016-01-01
Much has been written about the military events of December 7, 1941; however, little has been documented about the nurses' work and experience at Pearl Harbor, Hawaii. The aerial assault on Pearl Harbor was the first time in US history that Army nurses had been on the front line of battle. Nurses quickly triaged and stabilized those who could be saved, and provided compassion and comfort to those who were dying, in an environment where the nurses were unsure of their own survival. Traditional historical methods and a social history framework were used in this investigation. Primary sources included oral histories from the US Army Medical Department Center of History and Heritage and the State of Hawaii's website, Hawaii Aviation. Secondary sources included published books, newspaper articles, military websites, and history texts. Due to the limited bed capacity, Hickam Field Hospital converted to an evacuation hospital. Nurses, physicians, and medical corpsman triaged, stabilized, and transported those likely to survive, while staging the dead behind the building. The emergency room at Tripler Hospital was quickly flooded with patients from the battlefield, but the staff was able to sort patients appropriately to the wards, to the operating room, or provide comfort care as they died. At Schofield Hospital, collaboration between tireless doctors, nurses, and corpsmen was key to providing life-saving surgery and care.
Bowen, Lizabeth; Miles, A. Keith; Ballachey, Brenda E.; Waters, Shannon C.; Bodkin, James L.; Lindeberg, Mandy; Esler, Daniel N.
2017-01-01
The 1989 Exxon Valdez oil spill damaged a wide range of natural resources, including intertidal communities, and post-spill studies demonstrated acute and chronic exposure and injury to an array of species. Standard toxicological methods to evaluate petroleum contaminants have assessed tissue burdens, with fewer assays providing indicators of health or physiology, particularly when contaminant levels are low and chronic. Marine mussels are a ubiquitous and crucial component of the nearshore environment, and new genomic technologies exist to quantify molecular responses of individual mussels to stimuli, including exposure to polycyclic aromatic hydrocarbons (PAHs). We used gene-based assays of exposure and physiological function to assess chronic oil contamination using the Pacific blue mussel, Mytilus trossulus. We developed a diagnostic gene transcription panel to investigate exposure to PAHs and other contaminants and its effects on mussel physiology and health. During 2012–2015, we analyzed mussels from five field sites in western Prince William Sound, Alaska, with varying oil histories from the 1989 Exxon Valdez oil spill, and from three boat harbors in the area. Gene transcription patterns of mussels from harbors were consistent with elevated exposure to PAHs or other contaminants, whereas transcription patterns of mussels sampled from shorelines in areas affected by the oil spill indicated no PAH exposure.
Castro, Hector; Reddy, K. R.; Ogram, Andrew
2002-01-01
As a result of agricultural activities in regions adjacent to the northern boundary of the Florida Everglades, a nutrient gradient developed that resulted in physicochemical and ecological changes from the original system. Sulfate input from agricultural runoff and groundwater is present in soils of the Northern Everglades, and sulfate-reducing prokaryotes (SRP) may play an important role in biogeochemical processes such as carbon cycling. The goal of this project was to utilize culture-based and non-culture-based approaches to study differences between the composition of assemblages of SRP in eutrophic and pristine areas of the Everglades. Sulfate reduction rates and most-probable-number enumerations revealed SRP populations and activities to be greater in eutrophic zones than in more pristine soils. In eutrophic regions, methanogenesis rates were higher, the addition of acetate stimulated methanogenesis, and SRP able to utilize acetate competed to a limited degree with acetoclastic methanogens. A surprising amount of diversity within clone libraries of PCR-amplified dissimilatory sulfite reductase (DSR) genes was observed, and the majority of DSR sequences were associated with gram-positive spore-forming Desulfotomaculum and uncultured microorganisms. Sequences associated with Desulfotomaculum fall into two categories: in the eutrophic regions, 94.7% of the sequences related to Desulfotomaculum were associated with those able to completely oxidize substrates, and in samples from pristine regions, all Desulfotomaculum-like sequences were related to incomplete oxidizers. This metabolic selection may be linked to the types of substrates that Desulfotomaculum spp. utilize; it may be that complete oxidizers are more versatile and likelier to proliferate in nutrient-rich zones of the Everglades. Desulfotomaculum incomplete oxidizers may outcompete complete oxidizers for substrates such as hydrogen in pristine zones where diverse carbon sources are less available. PMID:12450837
Zhang, Juan; Xu, Liao; Zhou, Bo; Zhu, Yinyan; Jiang, Xiaoqing
2018-03-01
The pristine graphene can be easily prepared in isopropanol-water mixture with salts as assistant via liquid-phase exfoliation method. The concentration of graphene dispersion reaches as high as 0.565 mg/mL. The graphene film prepared by drop-casting method shows an excellent electrical conductivity (7.095 × 10 4 S/m). Furthermore, an electrochemical biosensor based on the pristine graphene shows high selectivity and sensitivity for the determination of dopamine. The linear detection range for dopamine is 2.5-1500 μM with detection limit of 1.5 μM. This method provides a potential process for preparing high-quality graphene ready-to-use in low-boiling point solvent. Copyright © 2017 Elsevier Inc. All rights reserved.
Magnetic Dirac Fermions and Chern Insulator Supported on Pristine Silicon Surface
NASA Astrophysics Data System (ADS)
Fu, Huixia; Liu, Zheng; Sun, Jia-Tao; Meng, Sheng
Emergence of ferromagnetism in non-magnetic semiconductors is strongly desirable, especially in topological materials thanks to the possibility to achieve quantum anomalous Hall effect. Based on first principles calculations, we propose that for Si thin film grown on metal substrate, the pristine Si(111)-r3xr3 surface with a spontaneous weak reconstruction has a strong tendency of ferromagnetism and nontrivial topological properties, characterized by spin polarized Dirac-fermion surface states. In contrast to conventional routes relying on introduction of alien charge carriers or specially patterned substrates, the spontaneous magnetic order and spin-orbit coupling on the pristine silicon surface together gives rise to quantized anomalous Hall effect with a finite Chern number C = -1. This work suggests exciting opportunities in silicon-based spintronics and quantum computing free from alien dopants or proximity effects.
A pristine eucrite-like gabbro from Descartes and its exotic kindred
NASA Technical Reports Server (NTRS)
Marvin, U. B.; Warren, P. H.
1980-01-01
A coarse-grained plagioclase-pyroxene gabbro (61224,6) with a cumulate texture suggestive of a slowly cooled plutonic rock was recovered from the 4-10 mm fraction of an Apollo 16 soil. The rock is uncommonly poor in feldspar and rich in Na for a lunar highlands lithology. Trace element analyses show extremely low siderophile element concentrations which confirm the pristine character indicated by the texture. The composition of 61224,6 is compared with those of 3 other pristine, exceptionally mafic, nonmare gabbros and of certain eucrites. 61224,6 and the three other gabbros have notable chemical differences but share relatively high ratios of Ti/Sm and Sc/Sm which suggest a possible genetic relationship. We conclude that 61224,6 represents a Na-rich cumulate from a layered intrusion within the highlands crust.
Ab-initio study of electronic and magnetic properties of Co-doped Mo2C monolayer
NASA Astrophysics Data System (ADS)
Mehta, Veenu; Tankeshwar, K.; Saini, Hardev S.
2018-05-01
The spin polarized density functional theory (DFT) based calculations has been performed to investigate the electronic and magnetic properties of pristine and Co-doped Mo2C using VASP code. The calculated results show that the pristine Mo2C is found to be non-magnetic whereas the Co dopant at Mo-site in the Mo2C monolayer generates the ferromagnetism in the resultant compound. The total magnetic moment of the system has been found to be 1.2µB which increases to 2.03µB as the concentration of Co increase from 3% to 8%, respectively. The electronic structure calculations of the pristine and Co-doped Mo2C show its metallic behavior which may found its application in magnetic energy storage devices, magnetic tape etc.
Gin, Stephane; Ryan, Joseph V.; Schreiber, Daniel K.; ...
2013-04-08
Here, we report and discuss results of atom probe tomography (APT) and energy-filtered transmission electron microscopy (EFTEM) applied to a borosilicate glass sample of nuclear interest altered for nearly 26 years at 90°C in a confined granitic medium in order to better understand the rate-limiting mechanisms under conditions representative of a deep geological repository for vitrified radioactive waste. The APT technique allows the 3D reconstruction of the elemental distribution at the reactive interphase with sub-nanometer precision. Profiles of the B distribution at pristine glass/hydrated glass interface obtained by different techniques are compared to show the challenge of accurate measurements ofmore » diffusion profiles at this buried interface on the nanometer length scale. Our results show that 1) Alkali from the glass and hydrogen from the solution exhibit anti-correlated 15 ± 3 nm wide gradients located between the pristine glass and the hydrated glass layer, 2) boron exhibits an unexpectedly sharp profile located just at the outside of the alkali/H interdiffusion layer; this sharp profile is more consistent with a dissolution front than a diffusion-controlled release of boron. The resulting apparent diffusion coefficients derived from the Li and H profiles are D Li = 1.5 × 10 -22 m 2.s -1 and D H = 6.8 × 10 -23 m 2.s -1. These values are around two orders of magnitude lower than those observed at the very beginning of the alteration process, which suggests that interdiffusion is slowed at high reaction progress by local conditions that could be related to the porous structure of the interphase. As a result, the accessibility of water to the pristine glass could be the rate-limiting step in these conditions. More generally, these findings strongly support the importance of interdiffusion coupled with hydrolysis reactions of the silicate network on the long-term dissolution rate, contrary to what has been suggested by recent interfacial dissolution-precipitation models for silicate minerals.« less
Noble Gas signatures of Enhanced Oil Recovery
NASA Astrophysics Data System (ADS)
Barry, P. H.; Kulongoski, J. T.; Tyne, R. L.; Hillegonds, D.; Byrne, D. J.; Landon, M. K.; Ballentine, C. J.
2017-12-01
Noble gases are powerful tracers of fluids from various oil and gas production activities in hydrocarbon reservoirs and nearby groundwater. Non-radiogenic noble gases are introduced into undisturbed oil and natural gas reservoirs through exchange with formation waters [1-3]. Reservoirs with extensive hydraulic fracturing, injection for enhanced oil recovery (EOR), and/or waste disposal also show evidence for a component of noble gases introduced from air [4]. Isotopic and elemental ratios of noble gases can be used to 1) assess the migration history of the injected and formation fluids, and 2) determine the extent of exchange between multiphase fluids in different reservoirs. We present noble gas isotope and abundance data from casing, separator and injectate gases of the Lost Hills and Fruitvale oil fields in the San Joaquin basin, California. Samples were collected as part of the California State Water Resource Control Board's Oil and Gas Regional Groundwater Monitoring Program. Lost Hills (n=7) and Fruitvale (n=2) gases are geochemically distinct and duplicate samples are highly reproducible. Lost Hills casing gas samples were collected from areas where EOR and hydraulic fracturing has occurred in the past several years, and from areas where EOR is absent. The Fruitvale samples were collected from a re-injection port. All samples are radiogenic in their He isotopes, typical of a crustal environment, and show enrichments in heavy noble gases, resulting from preferential adsorption on sediments. Fruitvale samples reflect air-like surface conditions, with higher air-derived noble gas concentrations. Lost Hills gases show a gradation from pristine crustal signatures - indicative of closed-system exchange with formation fluids - to strongly air-contaminated signatures in the EOR region. Pristine samples can be used to determine the extent of hydrocarbon exchange with fluids, whereas samples with excess air can be used to quantify the extent of EOR. Determining noble gas baseline values for pristine vs. recently modified (EOR, hydraulic fracturing) zones will be critical for interpreting the origin of any fugitive gases identified in nearby aquifers. [1] Ballentine et al., (1996) GCA, 60, 831-849 [2] Barry et al., (2016) GCA, 194, 291-309. [3] Barry et al., (2017) Geology, 45, 9. Darrah et al., (2014) PNAS 111, 39.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fan, Jiwen; Leung, Lai-Yung R.; DeMott, Paul J.
2014-01-03
Mineral dust aerosols often observed over California in winter and spring, associated with long-range transport from Asia and Sahara, have been linked to enhanced precipitation based on observations. Local anthropogenic pollution, on the other hand, was shown in previous observational and modeling studies to reduce precipitation. Here we incorporate recent developments in ice nucleation parameterizations to link aerosols with ice crystal formation in a spectral-bin cloud microphysical model coupled with the Weather Research and Forecasting (WRF) model, to examine the relative and combined impacts of dust and local pollution particles on cloud properties and precipitation type and intensity. Simulations aremore » carried out for two cloud cases with contrasting meteorology and cloud dynamics that occurred on February 16 (FEB16) and March 02 (MAR02) from the CalWater 2011 field campaign. In both cases, observations show the presence of dust and biological particles in a relative pristine environment. The simulated cloud microphysical properties and precipitation show reasonable agreement with aircraft and surface measurements. Model sensitivity experiments indicate that in the pristine environment, the dust and biological aerosol layers increase the accumulated precipitation by 10-20% from the Central Valley to the Sierra Nevada Mountains for both FEB16 and MAR02 due to a ~40% increase in snow formation, validating the observational hypothesis. Model results show that local pollution increases precipitation over the windward slope of the mountains by few percent due to increased snow formation when dust is present but reduces precipitation by 5-8% if dust is removed on FEB16. The effects of local pollution on cloud microphysics and precipitation strongly depend on meteorology including the strength of the Sierra Barrier Jet, and cloud dynamics. This study further underscores the importance of the interactions between local pollution, dust, and environmental conditions for assessing aerosol effects on cold season precipitation in California.« less
Jessica S. Lucas; Susan C. Loeb; Patrick G. R. Jodice
2015-01-01
Although several studies have described roost use by Rafinesqueâs big-eared bats (Corynorhinus rafinesquii), few studies have examined roost selection. We examined roost use and selection by Rafinesqueâs big-eared bat at the tree, stand, and landscape scales during the maternity season in pristine old-growth habitat in the Coastal Plain of South...
Pieces of the ancient lunar crust - Ages and composition of clasts in consortium breccia 67915
NASA Technical Reports Server (NTRS)
Marti, K.; Jost, D. T.; Aeschlimann, U.; Eberhardt, P.; Geiss, J.; Groegler, N.; Laul, J. C.; Ma, M.-S.; Schmitt, R. A.; Taylor, G. J.
1983-01-01
The composition and chronology of clasts representing three minor lithologies in consortium breccia 67915 are discussed. The lithologies studied are: sodic ferrogabbro, pristine troctolitic anorthosite (67915,26), and granulitic troctolitic anorthosite (67915,67). These lithologies were presumed to represent samples of the ancient lunar crust. The pristine troctolitic anorthosite, a typical member of the pristine anorthosite suite, contains little or no trapped liquid consistent with its two-phase mineralogy. The plagioclase separates have Ar-39-Ar-40 plateau ages of 4.10 + or - 0.06 b.y., and a final rise in the age pattern may represent a 'memory' of the earlier evolution. The granulitic troctolitic anorthosite, which has 13 times larger REE abundances, displays a continuous rise of the Ar-40/Ar-39 ratio. The last 25 percent of the Ar-39 release data establish a minimum age of over 3.5 b.y., but the Pu-244/Nd chronology suggests an age of about 4.3 b.y. The sodic ferrogabbro samples, which appear to be members of the Mg-gabbronorite group of pristine rocks, show large Ar losses but indicate plateaus in the low-temperature data, suggesting a metamorphic event more recently than 260 m.y. ago, a time that is consistent with the North Ray impact event 50 m.y. ago.
NASA Astrophysics Data System (ADS)
Wei, Ying; Yao, Kai; Wang, Xiaofeng; Jiang, Yihua; Liu, Xueyuan; Zhou, Naigen; Li, Fan
2018-01-01
In this paper, we demonstrate the high-performance inverted planar heterojunction perovskite solar cells (PeSCs) based on the novel inorganic hole-transporting layer (HTL) of silver (Ag)-doped NiOx (Ag:NiOx). Density-functional theory (DFT) calculation reveals that Ag prefers to occupy the substitutional Ni site (AgNi) and behaves as an acceptor in NiO lattice. Compared with the pristine NiOx films, appropriate Ag doping can increase the optical transparency, work function, electrical conductivity and hole mobility of NiOx films. Moreover, the CH3NH3PbI3 perovskite films grown on Ag:NiOx exhibit better crystallinity, higher coverage and smoother surface with densely packed larger grains than those grown on the pristine NiOx film. Consequently, the Ag:NiOx HTL boosts the efficiency of the inverted planar heterojunction PeSCs from 13.46% (for the pristine NiOx-based device) to 16.86% (for the 2 at.% Ag:NiOx-based device). Furthermore, the environmental stability of PeSCs based on Ag:NiOx HTL is dramatically improved compared to devices based on organic HTLs and pristine NiOx HTLs. This work provides a simple and effective HTL material system for high-efficient and stable PeSCs.
NASA Astrophysics Data System (ADS)
Moradi, Morteza; Nouraliei, Milad; Moradi, Reza
2017-03-01
Phenylpropanolamine (PPA) is a popular drug of abuse and its detection is of great importance for police and drug communities. Herein, we investigated the electronic sensitivity and reactivity of pristine, Al and Si doped C60 fullerenes to the PPA drug, using density functional theory calculations. Two adsorption mechanisms were predicted for PPA on the pristine C60 including cycloaddition and adsorption via -NH2 group. It was found that the pristine C60 has a good sensitivity to this drug but suffers from a weak interaction (adsorption energy -0.1 kcal/mol) because of structural deformation and aromaticity break. The PPA is adsorbed on the Al or Si doped C60 from its -OH or -NH2 groups. The Al-doping significantly improves the reactivity of C60 but decreases its electronic sensitivity. Unlike the Al-doping, the Si-doping increases both the reactivity and electronic sensitivity to the PPA drug. At the presence of PPA drug, the conductivity of the Si-doped C60 considerably increases due to the HOMO-LUMO gap reduction by about 30.3%. Different analyses were used to obtain the results including nucleus independent chemical shift (NICS), density of states (DOS), molecular electrostatic potential (MEP), frontier molecular orbitals (FMO), etc.
Overcoming complexities: Damage detection using dictionary learning framework
NASA Astrophysics Data System (ADS)
Alguri, K. Supreet; Melville, Joseph; Deemer, Chris; Harley, Joel B.
2018-04-01
For in situ damage detection, guided wave structural health monitoring systems have been widely researched due to their ability to evaluate large areas and their ability detect many types of damage. These systems often evaluate structural health by recording initial baseline measurements from a pristine (i.e., undamaged) test structure and then comparing later measurements with that baseline. Yet, it is not always feasible to have a pristine baseline. As an alternative, substituting the baseline with data from a surrogate (nearly identical and pristine) structure is a logical option. While effective in some circumstance, surrogate data is often still a poor substitute for pristine baseline measurements due to minor differences between the structures. To overcome this challenge, we present a dictionary learning framework to adapt surrogate baseline data to better represent an undamaged test structure. We compare the performance of our framework with two other surrogate-based damage detection strategies: (1) using raw surrogate data for comparison and (2) using sparse wavenumber analysis, a precursor to our framework for improving the surrogate data. We apply our framework to guided wave data from two 108 mm by 108 mm aluminum plates. With 20 measurements, we show that our dictionary learning framework achieves a 98% accuracy, raw surrogate data achieves a 92% accuracy, and sparse wavenumber analysis achieves a 57% accuracy.
NASA Astrophysics Data System (ADS)
Vats, T.; Dutt, S.; Kumar, R.; Siril, P. F.
2016-09-01
Amazing conductivity, perfect honeycomb sp2 arrangement and the high theoretical surface area make pristine graphene as one of the best materials suited for application as catalyst supports. Unfortunately, the low reactivity of the material makes the formation of nanocomposite with inorganic materials difficult. Here we report an easy approach to synthesize nanocomposites of pristine graphene with palladium (Pd-G) using swollen liquid crystals (SLCs) as a soft template. The SLC template gives the control to deposit very small Pd particles of uniform size on G as well as RGO. The synthesized nanocomposite (Pd-G) exhibited exceptionally better catalytic activity compared with Pd-RGO nanocomposite in the hydrogenation of nitrophenols and microwave assisted C-C coupling reactions. The catalytic activity of Pd-G nanocomposite during nitrophenol reduction reaction was sixteen times higher than Pd nanoparticles and more than double than Pd-RGO nanocomposite. The exceptionally high activity of pristine graphene supported catalysts in the organic reactions is explained on the basis of its better pi interacting property compared to partially reduced RGO. The Pd-G nanocomposite showed exceptional stability under the reaction conditions as it could be recycled upto a minimum of 15 cycles for the C-C coupling reactions without any loss in activity.
1980-10-01
looked all the way from the west to all the way down to Erie , Pennsylvania . We made some initial cuts and got it down to five different ports...Harbor, MN Presque Isle :Two Harbors, MN :Gary, IN 1,721,920 25 (Litton Great Lakes):Two Harbors, MN :Calumet Harbor, IN 178,080 3 :Two Harbors, MN...WI : 2 :11 : 0: 0 : 0: 2: 3 Silver Bay, MN : 82 :67 : 96 :87 : 85 : 88: 89 Taconite, MN : 0 : 0 : 0: 0 : 0: 4: 0 Presque Isle , MI : 6 2 : 1 0.5: 2 1
Zhang, Rui; Yang, Peilong; Huang, Huoqing; Shi, Pengjun; Yuan, Tiezheng; Yao, Bin
2011-11-01
Microbial phytases play a major role in the mineralization of organic phosphorous, especially in symbiotic plants and animals. In this study, we identified two types of phytases in Serratia sp. TN49 that was harbored in the gut of Batocera horsfieldi (Coleoptera) larvae. The two phytases, an acidic histidine acid phosphatase (PhyH49) and an alkaline β-propeller phytase (PhyB49), shared low identities with known phytases (61% at most). PhyH49 and PhyB49 produced in Escherichia coli exhibited maximal activities at pH 5.0 (60°C) and pH 7.5-8.0 (45°C), respectively, and are complementary in phytate degradation over the pH range 2.0-9.0. Serratia sp. TN49 harboring both PhyH49 and PhyB49 might make it more adaptive to environment change, corresponding to the evolution trend of microorganism.
Microplastic pollution in the marine waters and sediments of Hong Kong.
Tsang, Y Y; Mak, C W; Liebich, C; Lam, S W; Sze, E T-P; Chan, K M
2017-02-15
The presence of plastic waste with a diameter of less than 5mm ("microplastics") in marine environments has prompted increasing concern in recent years, both locally and globally. We conducted seasonal surveys of microplastic pollution in the surface waters and sediments from Deep Bay, Tolo Harbor, Tsing Yi, and Victoria Harbor in Hong Kong between June 2015 and March 2016. The average concentrations of microplastics in local coastal waters and sediments respectively ranged from 51 to 27,909particles per 100m 3 and 49 to 279particles per kilogram. Microplastics of different shapes (mainly fragments, lines, fibers, and pellets) were identified as polypropylene, low-density polyethylene, high-density polyethylene, a blend of polypropylene and ethylene propylene, and styrene acrylonitrile by means of Attenuated Total Reflectance - Fourier Transform Infrared Spectroscopy. This is the first comprehensive study to assess the spatial and temporal variations of microplastic pollution in Hong Kong coastal regions. Copyright © 2016 Elsevier Ltd. All rights reserved.
Tracking Three-Dimensional Fish Behavior with a New Marine Acoustic Telemetry System
NASA Technical Reports Server (NTRS)
Brosnan, Ian G.; McGarry, Louise P.; Greene, Charles H.; Steig, Tracey W.; Johnston, Samuel V.; Ehrenberg, John E.
2015-01-01
The persistent monitoring capability provided by acoustic telemetry systems allows us to study behavior, movement, and resource selection of mobile marine animals. Current marine acoustic telemetry systems are challenged by localization errors and limits in the number of animals that can be tracked simultaneously. We designed a new system to provide detection ranges of up to 1 km, to reduce localization errors to less than 1 m, and to increase to 500 the number of unique tags simultaneously tracked. The design builds on HTIs experience of more than a decade developing acoustic telemetry systems for freshwater environments. A field trial of the prototype system was conducted at the University of Washingtons Friday Harbor Marine Laboratory (Friday Harbor, WA). Copper rockfish (Sebastes caurinus) were selected for field trials of this new system because their high site-fidelity and small home ranges provide ample opportunity to track individual fish behavior while testing our ability to characterize the movements of a species of interest to management authorities.
Hexabromocyclododecanes (HBCDs) in fish: Evidence of recent HBCD input into the coastal environment.
Sun, Runxia; Luo, Xiaojun; Zheng, Xiaobo; Cao, Kun; Peng, Pingan; Li, Qing X; Mai, Bixian
2018-01-01
Hexabromocyclododecanes (HBCDs) are flame retardants and emerging persistent organic pollutants. In the present study, α-, β-, and γ-HBCDs were measured in several fish species from rivers and an electronic waste (e-waste) recycling site in Pearl River Delta, South China. The concentrations of HBCDs were 12.8 to 640, 5.90 to 115, and 34.3 to 518ng/g lipid weight (lw) in mud carp (Cirrhinus molitorella), tilapia (Tilapia nilotica), and plecostomus (Hypostomus plecostomus), respectively. Plecostomus showed the highest HBCD concentrations among three fish species. The contributions of α-HBCD to total HBCDs were 78% to 97%, 93% to 99%, and 87% to 98% in carp, tilapia, and plecostomus, respectively. Fish samples from a harbor and the e-waste site exhibited the highest HBCD concentrations among all samples. The HBCD concentrations were not significantly correlated with the gross domestic product or population data. e-Waste recycling activities, harbor construction, and shipment might be recent HBCD sources. Copyright © 2017 Elsevier Ltd. All rights reserved.
FEEDBACK FROM MASSIVE STARS AND GAS EXPULSION FROM PROTO-GLOBULAR CLUSTERS
DOE Office of Scientific and Technical Information (OSTI.GOV)
Calura, F.; Romano, D.; D’Ercole, A.
2015-11-20
Globular clusters (GCs) are considerably more complex structures than previously thought, harboring at least two stellar generations that present clearly distinct chemical abundances. Scenarios explaining the abundance patterns in GCs mostly assume that originally the clusters had to be much more massive than today, and that the second generation of stars originates from the gas shed by stars of the first generation (FG). The lack of metallicity spread in most GCs further requires that the supernova-enriched gas ejected by the FG is completely lost within ∼30 Myr, a hypothesis never tested by means of three-dimensional hydrodynamic simulations. In this paper,more » we use 3D hydrodynamic simulations including stellar feedback from winds and supernovae, radiative cooling and self-gravity to study whether a realistic distribution of OB associations in a massive proto-GC of initial mass M{sub tot} ∼ 10{sup 7} M{sub ⊙} is sufficient to expel its entire gas content. Our numerical experiment shows that the coherence of different associations plays a fundamental role: as the bubbles interact, distort, and merge, they carve narrow tunnels that reach deeper and deeper toward the innermost cluster regions, and through which the gas is able to escape. Our results indicate that after 3 Myr, the feedback from stellar winds is responsible for the removal of ∼40% of the pristine gas, and that after 14 Myr, 99% of the initial gas mass has been removed.« less
DOT National Transportation Integrated Search
2004-07-31
This case study tells the story of a successful and collaborative transportation planning process at Boston Harbor Islands National Park Area (Boston Harbor Islands). By using an innovative approach to planning, Boston Harbor Islands has been able to...
Disposal of Vessel Wastes: Shipboard and Shoreside Facilities. Phase 2. Graywater
1979-07-01
Increase in Concentration Resulting from Daily Loadings and Vessel-Induced Mixing 45 3-7 Annual Loadings to Presque Isle - Marquette Harbor from...in port for 24 hours (Upper Lakes Reference Group, 1977a). Two harbors were considered for case studies. The first harbor, Presque Isle -Marquette...harbor. Presque Isle -Marquette The existing conditions of the harbor are considered to be of high quality with respect to coastal waters, the open waters
Multiple Smaller Missions as a Direct Pathway to Mars Sample Return
NASA Technical Reports Server (NTRS)
Niles, P. B.; Draper, D. S.; Evans, C. A.; Gibson, E. K.; Graham, L. D.; Jones, J. H.; Lederer, S. M.; Ming, D.; Seaman, C. H.; Archer, P. D.;
2012-01-01
Recent discoveries by the Mars Exploration Rovers, Mars Express, Mars Odyssey, and Mars Reconnaissance Orbiter spacecraft include multiple, tantalizing astrobiological targets representing both past and present environments on Mars. The most desirable path to Mars Sample Return (MSR) would be to collect and return samples from that site which provides the clearest examples of the variety of rock types considered a high priority for sample return (pristine igneous, sedimentary, and hydrothermal). Here we propose an MSR architecture in which the next steps (potentially launched in 2018) would entail a series of smaller missions, including caching, to multiple landing sites to verify the presence of high priority sample return targets through in situ analyses. This alternative architecture to one flagship-class sample caching mission to a single site would preserve a direct path to MSR as stipulated by the Planetary Decadal Survey, while permitting investigation of diverse deposit types and providing comparison of the site of returned samples to other aqueous environments on early Mars
Bioaccumulation of heavy metals in plant leaves from Yan׳an city of the Loess Plateau, China.
Hu, Youning; Wang, Dexiang; Wei, Lijing; Zhang, Xinping; Song, Bin
2014-12-01
Urban plants are capable of reducing environmental pollutions through bioaccumulation contaminants in their tissues. The accumulation of heavy metals (Pb, Cu, Cd, Cr, and Zn) in leaves of nine tree species and five shrub species from Yan׳an city of China were investigated, and total metal accumulation capacities of different plants were evaluated using the metal accumulation index (MAI). The results indicated that plants in polluted environments are enriched in heavy metals relative to those in pristine environments, this is mainly caused by traffic emissions and coal combustion. Species with the highest accumulation of a single metal did not have the highest total metal accumulation capacity, the MAI should be an important indicator for tree species selection in phytoextraction and urban greening. Considering total accumulation capacities, Sabina chinensis, Juniperus formosana, Ailanthus altissima and Salix matsudana var. matsudana could be widely used in the Loess Plateau. Copyright © 2014 Elsevier Inc. All rights reserved.
Amde, Meseret; Liu, Jing-Fu; Tan, Zhi-Qiang; Bekana, Deribachew
2017-11-01
Metal oxide nanoparticles (MeO-NPs) are among the most consumed NPs and also have wide applications in various areas which increased their release into the environmental system. Aquatic (water and sediments) and terrestrial compartments are predicted to be the destination of the released MeO-NPs. In these compartments, the particles are subjected to various dynamic processes such as physical, chemical and biological processes, and undergo transformations which drive them away from their pristine state. These transformation pathways can have strong implications for the fate, transport, persistence, bioavailability and toxic-effects of the NPs. In this critical review, we provide the state-of-the-knowledge on the transformation processes and bioavailability of MeO-NPs in the environment, which is the topic of interest to researchers. We also recommend future research directions in the area which will support future risk assessments by enhancing our knowledge of the transformation and bioavailability of MeO-NPs. Copyright © 2017 Elsevier Ltd. All rights reserved.
Modern inhalation anesthetics: Potent greenhouse gases in the global atmosphere
NASA Astrophysics Data System (ADS)
Vollmer, Martin K.; Rhee, Tae Siek; Rigby, Matt; Hofstetter, Doris; Hill, Matthias; Schoenenberger, Fabian; Reimann, Stefan
2015-03-01
Modern halogenated inhalation anesthetics undergo little metabolization during clinical application and evaporate almost completely to the atmosphere. Based on their first measurements in a range of environments, from urban areas to the pristine Antarctic environment, we detect a rapid accumulation and ubiquitous presence of isoflurane, desflurane, and sevoflurane in the global atmosphere. Over the past decade, their abundances in the atmosphere have increased to global mean mole fractions in 2014 of 0.097ppt, 0.30ppt, and 0.13ppt (parts per trillion, 10-12, in dry air), respectively. Emissions of these long-lived greenhouse gases inferred from the observations suggest a global combined release to the atmosphere of 3.1 ± 0.6 million t CO2 equivalent in 2014 of which ≈80% stems from desflurane. We also report on halothane, a previously widely used anesthetic. Its global mean mole fraction has declined to 9.2ppq (parts per quadrillion, 10-15) by 2014. However, the inferred present usage is still 280 ±120t yr-1.
Fourqurean, James W; Muth, Meredith F; Boyer, Joseph N
2010-07-01
Despite marked gradients in nutrient availability that control the abundance and species composition of seagrasses in south Florida, and the importance of nutrient availability in controlling abundance and composition of epiphytes on seagrasses in other locations, we did not find that epiphyte load on the dominant seagrass, Thalassia testudinum, or that the relative contribution of algal epiphytes to the epiphyte community, was positively correlated with nutrient availability in the water column or the sediment in oligotrophic seagrass beds. Further, the abundance of microphytobenthos, as indicated by Chlorophyll-a concentration in the sediments, was not directly correlated with concentrations of nutrients in the sediments. Our results suggest that epiphyte and microphytobenthos abundance are not unambiguous indicators of nutrient availability in relatively pristine seagrass environments, and therefore would make poor candidates for indicators of the status and trends of seagrass ecosystems in relatively low-nutrient environments like the Florida Keys. Copyright 2010 Elsevier Ltd. All rights reserved.
Correia, D M; Sencadas, V; Ribeiro, C; Martins, P M; Martins, P; Gama, F M; Botelho, G; Lanceros-Méndez, S
2016-08-15
Biodegradable poly(l-lactic acid) (PLLA) and PLLA/CoFe2O4 magnetic microspheres with average sizes ranging between 0.16-3.9μm and 0.8-2.2μm, respectively, were obtained by an oil-in-water emulsion method using poly(vinyl alcohol) (PVA) solution as the emulsifier agent. The separation of the microspheres in different size ranges was then performed by centrifugation and the colloidal stability assessed at different pH values. Neat PLLA spheres are more stable in alkaline environments when compared to magnetic microspheres, both types being stable for pHs higher than 4, resulting in a colloidal suspension. On the other hand, in acidic environments the microspheres tend to form aggregates. The neat PLLA microspheres show a degree of crystallinity of 40% whereas the composite ones are nearly amorphous (17%). Finally, the biocompatibility was assessed by cell viability studies with MC3T3-E1 pre-osteoblast cells. Copyright © 2016 Elsevier Inc. All rights reserved.
Rezzonico, Enea; Mestdagh, Renaud; Delley, Michèle; Combremont, Séverine; Dumas, Marc-Emmanuel; Holmes, Elaine; Nicholson, Jeremy; Bibiloni, Rodrigo
2011-01-01
Rodent models harboring a simple yet functional human intestinal microbiota provide a valuable tool to study the relationships between mammals and their bacterial inhabitants. In this study, we aimed to develop a simplified gnotobiotic mouse model containing 10 easy-to-grow bacteria, readily available from culture repositories, and of known genome sequence, that overall reflect the dominant commensal bacterial makeup found in adult human feces. We observed that merely inoculating a mix of fresh bacterial cultures into ex-germ free mice did not guarantee a successful intestinal colonization of the entire bacterial set, as mice inoculated simultaneously with all strains only harbored 3 after 21 d. Therefore, several inoculation procedures were tested and levels of individual strains were quantified using molecular tools. Best results were obtained by inoculating single bacterial strains into individual animals followed by an interval of two weeks before allowing the animals to socialize to exchange their commensal microbes. Through this procedure, animals were colonized with almost the complete bacterial set (9/10). Differences in the intestinal composition were also reflected in the urine and plasma metabolic profiles, where changes in lipids, SCFA, and amino acids were observed. We conclude that adaptation of bacterial strains to the host's gut environment (mono-colonization) may predict a successful establishment of a more complex microbiota in rodents.
Duncan, Danielle L; Carls, Mark G; Rice, Stanley D; Stekoll, Michael S
2017-05-01
Polycyclic aromatic hydrocarbons (PAHs) from creosote exposure in the laboratory resulted in deleterious effects in developing Pacific herring (Clupea pallasi) embryos, and potentially toxic concentrations of PAHs were measured using passive water samplers at 1 of 3 harbor field sites in Juneau, Alaska, USA. Aqueous total PAH concentrations of 4.6 μg/L and 8.4 μg/L from creosote exposure resulted in skeletal defects and ineffective swimming in hatched larvae in the laboratory (10% effective concentrations) and were the most sensitive parameters measured. Hatch rates also suffered from creosote exposure in a dose-dependent manner: at exposures between 5 μg/L and 50 μg/L total PAH, 50% of the population failed to hatch. Comparisons between laboratory and field deployed passive samplers suggested that for at least 1 harbor in Juneau, concentrations sufficient to induce teratogenic effects were found directly on creosoted pilings, within 10 cm of them, and sometimes at a distance of 10 m. Total PAH concentrations generally decreased with distance from creosoted pilings. Creosote pilings contribute to the PAH load within a marina and can rise to PAH concentrations that are harmful to fish embryos, but at a scale that is localized in the environment. Environ Toxicol Chem 2017;36:1261-1269. © 2016 SETAC. © 2016 SETAC.
Huber, R; Huber, H; Stetter, K O
2000-12-01
Ecological studies have shown that water-containing terrestrial, subterranean and submarine high-temperature environments harbor a great diversity of hyperthermophilic prokaryotes, growing fastest at temperatures of 80 degrees C or above. The investigations included cultivation, isolation and detailed analysis of these hyperthermophiles as well as in situ 16S rRNA gene sequence analysis and in situ hybridization studies. For a safe and fast isolation of novel hyperthermophiles from mixed cultures, a new, plating-independent isolation technique was developed, based on the use of a laser microscope ('optical tweezers'). This method, combined with 16S rRNA gene sequence analysis and whole-cell hybridization using fluorescently labelled oligonucleotide probes, even allows the recovery of pure cultures of phylogenetically predicted organisms harboring novel 16S rRNA gene sequences. In their natural habitats, hyperthermophiles form complex food webs, consisting of primary producers and consumers of organic material. Their metabolic potential includes various types of aerobic and anaerobic respiration and different modes of fermentation. In hydrothermal and geothermal environments, hyperthermophiles have important ecological functions in biogeochemical processes. Members of the Sulfolobales are able to mobilize heavy metals from sulfidic ores like pyrite or chalcopyrite. Biomineralization processes of hyperthermophiles include the formation of magnetite from iron or the precipitation of arsenate as realgar, a reaction performed by a novel hyperthermophile that was isolated from Pisciarelli Solfatara, Naples, Italy.
Sun, Runxia; Sun, Yue; Li, Qing X; Zheng, Xiaobo; Luo, Xiaojun; Mai, Bixian
2018-05-30
Intensive human activities aggravate environmental pollution, particularly in the coastal environment. Sixteen priority polycyclic aromatic hydrocarbons (PAHs) were determined in the sediments and marine species from Zhanjiang Harbor, a large harbor in China. The total PAH concentrations ranged from 151 to 453 ng/g dry weight (dw) in sediments and from 86.7 to 256 ng/g wet weight (ww) in organism tissues. High levels of PAHs occurred in the sample sites next to the estuary. A decrease in PAH levels was observed in comparison to the previous survey prior to 2012. Fish exhibited lower lipid weight normalized PAH concentrations than the other species, which may be related to their efficient metabolic transformation. Three ring PAHs dominated both in marine sediments and species, but low molecular weight PAHs exhibited higher proportions in biota than in sediments (p < 0.05). Petrogenic and pyrolytic sources both contributed to the occurrence of PAHs, and the latter became increasingly important in the study area. The ecological risk from PAHs in the sediments was relatively low (9% incidence of adverse biological effect) according to the effects-based sediment quality guideline values. Exposure to PAHs via consuming seafoods might pose a health risk to local residents. Overall, these results revealed anthropogenic activities in the coastal area have an impact on the local ecosystem. Copyright © 2018 Elsevier B.V. All rights reserved.
Foote, Andrew D; Thomsen, Philip Francis; Sveegaard, Signe; Wahlberg, Magnus; Kielgast, Jos; Kyhn, Line A; Salling, Andreas B; Galatius, Anders; Orlando, Ludovic; Gilbert, M Thomas P
2012-01-01
The exploitation of non-invasive samples has been widely used in genetic monitoring of terrestrial species. In aquatic ecosystems, non-invasive samples such as feces, shed hair or skin, are less accessible. However, the use of environmental DNA (eDNA) has recently been shown to be an effective tool for genetic monitoring of species presence in freshwater ecosystems. Detecting species in the marine environment using eDNA potentially offers a greater challenge due to the greater dilution, amount of mixing and salinity compared with most freshwater ecosystems. To determine the potential use of eDNA for genetic monitoring we used specific primers that amplify short mitochondrial DNA sequences to detect the presence of a marine mammal, the harbor porpoise, Phocoena phocoena, in a controlled environment and in natural marine locations. The reliability of the genetic detections was investigated by comparing with detections of harbor porpoise echolocation clicks by static acoustic monitoring devices. While we were able to consistently genetically detect the target species under controlled conditions, the results from natural locations were less consistent and detection by eDNA was less successful than acoustic detections. However, at one site we detected long-finned pilot whale, Globicephala melas, a species rarely sighted in the Baltic. Therefore, with optimization aimed towards processing larger volumes of seawater this method has the potential to compliment current visual and acoustic methods of species detection of marine mammals.
Wu, Shijin; Li, Yuan; Wang, Penghua; Zhong, Li; Qiu, Lequan; Chen, Jianmeng
2016-04-01
The environmental risk of fluoride and chloride pollution is pronounced in soils adjacent to solar photovoltaic sites. The elevated levels of fluoride and chloride in these soils have had significant impacts on the population size and overall biological activity of the soil microbial communities. The microbial community also plays an essential role in remediation of these soils. Questions remain as to how the fluoride and chloride contamination and subsequent remediation at these sites have impacted the population structure of the soil microbial communities. We analyzed the microbial communities in soils collected from close to a solar photovoltaic enterprise by pyrosequencing of the 16S rRNA tag. In addition, we used multivariate statistics to identity the relationships shared between sequence diversity and heterogeneity in the soil environment. The overall microbial communities were surprisingly diverse, harboring a wide variety of taxa and sharing significant correlations with different degrees of fluoride and chloride contamination. The contaminated soils harbored abundant bacteria that were probably resistant to the high acidity, high fluoride and chloride concentration, and high osmotic pressure environment. The dominant genera were Sphingomonas, Subgroup_6_norank, Clostridium sensu stricto, Nitrospira, Rhizomicrobium, and Acidithiobacillus. The results of this study provide new information regarding a previously uncharacterized ecosystem and show the value of high-throughput sequencing in the study of complex ecosystems.
X-ray Spectromicroscopy Studies of Nanoparticles in the Environment
NASA Astrophysics Data System (ADS)
Sedlmair, J.; Gleber, S.-C.; Schirz, A.; Zanker, H.; Thieme, J.
2009-04-01
Motivation: In recent time, carbon nanotubes (CNTs) have drawn a lot of attention due to their unique properties and due to that possible application, for instance in pharmacology, material sciences or as semiconductors. CNTs are tubes with diameters in the nanometer scale, but with lengths up to several millimeters. Their walls consist of carbon atoms, each bound to three other carbon atoms (sp2-hybridization), which results in a hexagonal honeycomb-like structure. They can also be functionalized, e.g. with carboxyl- or hydroxyl groups. Although the production and modification of CNTs in sizable quantities have been improved continuously, the characterization of these nano-particles still needs to be advanced. Additionally, the ecological aspect comes into account. Since most of these new materials consist of particles too small to be biodegraded, it is important to analyze the impact of CNTs on the environment (and biomolecular matter in general). Here we present the result of a study of pristine and functionalized carbon nanotubes (CNTs) using the x-ray scanning transmission microscope (STXM) at the storage ring BESSY II in Berlin for a NEXAFS (near edge x-ray absorption spectroscopy) analysis with spatial resolution. Experiment and results: We characterized three types of multi-walled CNTs (3-15 walls, outer diameter of 13-16 nm and length distribution 1-10 nm) by x-ray spectromicroscopy. To be more specific, we have investigated different CNT-samples with energies around the C1s K-shell edge (~284 eV) dry and in aqueous environment at ambient conditions. Using the STXM, the spatial information from the x-ray image with a pixel size of 50 nm can be combined with NEXAFS-spectra[5] of each pixel of the image area. The differences between the species are observable both in the microscopic images and the spectral data. The evaluation[1][2] of the NEXAFS-spectra yields information about the chemical bindings in the sample. Discussion The difference between the reference sample and its modifications, CNTs with carboxyl-groups, and CNTs with COOH-groups loaded with depleted uranium are clearly visible. The x-ray-microscopic images show that the expected curly-network structure expected for all samples is only observable in the case of the pristine CNTs (reference). With the additional binding of depleted uranium, the network structure has vanishes totally. Instead, the particulate character becomes the dominant form. In all three cases, the NEXAFS-spectra unambiguously revealed the binding forms C=C and, if present, C=O. The comparison of their spectra makes furthermore clear, how the changed environment of a bond influences its position on the energy scale. In addition to that, we recently studied the behavior of pristine and carboxylated CNTs in aqueous media and their interaction with soils. Comprising, the STXM is ideally suited for examinations like this, since it combines x-ray imaging techniques with NEXAFS-spectroscopy[3][4][6], and the samples can stay at ambient conditions throughout the whole experiment. Future experiments will concentrate on CNTs in combination with other materials to reveal further insights into the interaction of nano-particles with other substances, for instance soils and in building materials. Literature: [1] Gleber G, 2002, XRMX-Ray Microscopy: Proceedings of the Seventh International Conference (Berkeley, CA 1999) [2] Jacobsen C, Flynn G, Wirick S, and Zimba C, 2000, J Microscopy, 197 (2), p 173-184 [3] Mitrea G, Thieme J, Guttmann P, Heim S, Gleber S-C, 2008, J Synchrotron Radiat., 15 (Pt 1), p 26-35 [4] Nováková E, Mitrea G, Peth C, Thieme J, Mann K, Salditt T, 2008, Biointerphases, 3 (2) [5] Stöhr J, 1992, NEXAFS Spectroscopy (Berlin: Springer Verlag) [6] Thieme J, McNulty I, Vogt S and Paterson D, 2007, Environ Sci & Technol., 41 (20), p 6885-6889
Decadal Changes In Benthic Community Measures In New York Harbor
Monitoring in New York Harbor, NY, as part of the Regional Environmental Monitoring and Assessment Program has spanned a decade, and includes habitat and water quality measures and sediment contaminant levels from four sub-basins (Upper NY Harbor, Lower NY Harbor, Newark Bay, and...
2003-08-04
WI........................................21-2 2. Alpena Harbor, MI .........................................21-3 3. Arcadia Harbor, MI...DISTRICT $292,010 was for new work and $1,701,185 for maintenance. 2. ALPENA HARBOR, MI Location. At mouth of Thunder Bay River which empties into...Thunder Bay, Lake Huron. Harbor is 100 miles southeast of Cheboygan Harbor, MI. River has its source in Montmorency and Alpena Counties, MI. (See
33 CFR 165.904 - Lake Michigan at Chicago Harbor & Burnham Park Harbor-Safety and Security Zone.
Code of Federal Regulations, 2012 CFR
2012-07-01
... & Burnham Park Harbor-Safety and Security Zone. 165.904 Section 165.904 Navigation and Navigable Waters... Guard District § 165.904 Lake Michigan at Chicago Harbor & Burnham Park Harbor—Safety and Security Zone... entrance of the harbor connecting coordinates 41°51′09″ N, 087°36′36″W and 41°51′11″ N, 087°36′22″ W. (b...
33 CFR 165.904 - Lake Michigan at Chicago Harbor & Burnham Park Harbor-Safety and Security Zone.
Code of Federal Regulations, 2014 CFR
2014-07-01
... & Burnham Park Harbor-Safety and Security Zone. 165.904 Section 165.904 Navigation and Navigable Waters... Guard District § 165.904 Lake Michigan at Chicago Harbor & Burnham Park Harbor—Safety and Security Zone... entrance of the harbor connecting coordinates 41°51′09″ N, 087°36′36″ W and 41°51′11″ N, 087°36′22″ W. (b...
33 CFR 165.904 - Lake Michigan at Chicago Harbor & Burnham Park Harbor-Safety and Security Zone.
Code of Federal Regulations, 2013 CFR
2013-07-01
... & Burnham Park Harbor-Safety and Security Zone. 165.904 Section 165.904 Navigation and Navigable Waters... Guard District § 165.904 Lake Michigan at Chicago Harbor & Burnham Park Harbor—Safety and Security Zone... entrance of the harbor connecting coordinates 41°51′09″ N, 087°36′36″W and 41°51′11″ N, 087°36′22″ W. (b...
The milling of pristine and brominated P-100 graphite fibers
NASA Technical Reports Server (NTRS)
Dillehay, M. E.; Gaier, J. R.
1986-01-01
Techniques were developed for the ball milling of pristine and brominated P-100 graphite fibers. Because of the lubrication properties of graphite, large ball loads (50 percent by volume) were required. Use of 2-propanol as a milling medium enhanced the efficiency of the process. Milled brominated P-100 fibers had resistivities which were indistinguishable from milled pristine P-100 fibers. Apparent loss of bromine from the brominated fibers suggests that bromine would not be the intercalate of choice in applications where milled fibers of this type are required. Other intercalates which do not degas may be more appropriate for a milled fiber application. These same results, however, do provide evidence that bromine molecules leave the fiber surface when removed from overpressure of bromine. While exploring possible solvent media for milling purposes, it was found that brominated fibers are stable in a wide variety of organic solvents.
NASA Astrophysics Data System (ADS)
Christopher, Benedict; Rao, Ashok; Deka, Utpal; Prasad K, Shyam; Okram, G. S.; Sanjeev, Ganesh; Chandra Petwal, Vikash; Verma, Vijay Pal; Dwivedi, Jishnu
2018-07-01
The study of electronic and magnetic properties of electron beam (EB) irradiated PrCoO3 manganites is presented in this communication. The diffraction data confirms that pristine as well as electron beam irradiated samples are single phased and they crystalize at orthorhombic distorted structure with Pbnm space group. The electrical resistivity of all the samples reveals semiconducting behavior. Small polaron hopping model is appropriately employed to investigate the semiconducting nature of the pristine and EB irradiated samples. The Seebeck coefficient (S) data of the pristine sample exhibits colossally high positive value (about 300 mV/K) and substantial decrease in S value is noticed in the irradiated samples. The high temperature analysis of thermopower data validates the small polaron hopping model. The magnetic measurements display possible existence of super-paramagnetic characteristics in the samples.
Work function tunability of borophene via doping: A first principle study
NASA Astrophysics Data System (ADS)
Katoch, Neha; Sharma, Munish; Thakur, Rajesh; Ahluwalia, P. K.
2018-04-01
A first principle study of structural properties, work function and electronic properties of pristine and substitutional doped borophene atomic layer with X atoms (X = F, Cl, H, Li, Na) have been carried out within the framework of density functional theory (DFT). Studied adsorption energies are high for all dopants indicating adsorption to be chemisorption type. The reduction in work function of pristine borophene has been found with n-type (Li, Na) dopants is of the order of 0.42 eV which is higher than that of the reduction in work function of borophene with p-type (F, Cl) dopants. For H dopants there is no reduction in work function of borophene. Quantum ballistic conductance has been found to modulate with doping. The quantum ballistic conductance is decreasing for doped borophene in the order Li > Cl ˜ H ˜ Na > F as compared to pristine borophene.
Zhang, Meng-tao; Zhang, Qing; Kang, Xin-gang; Yang, Ying-jun; Xu, Guang; Zhang, Li-xin
2015-06-01
Based on the analysis of three forest communities (polar-birch secondary forest, spruce-fir mixed forest, spruce-fir near pristine forest) in Changbai Mountains, a total of 22 factors of 5 indices, including the population regeneration, soil fertility (soil moisture and soli nutrient), woodland productivity and species diversity that reflected community characteristics were used to evaluate the stability of forest community succession at different stages by calculating subordinate function values of a model based on fuzzy mathematics. The results that the indices of population regeneration, soli nutrient, woodland productivity and species diversity were the highest in the spruce-fir mixed forest, and the indices of soil moisture were the highest in the spruce-fir near-pristine forest. The stability of three forest communities was in order of natural spruce-fir mixed forest > spruce-fir near pristine forest > polar-birch secondary forest.
Dehydrogenation of methanol to formaldehyde catalyzed by pristine and defective ceria surfaces
DOE Office of Scientific and Technical Information (OSTI.GOV)
Beste, Ariana; Overbury, Steven H.
We have explored the dehydrogenation of methoxy on pristine and defective (111), (100), and (110) ceria surfaces with density functional methods. Methanol conversion is used as a probe reaction to understand structure sensitivity of the oxide catalysis. Differences in reaction selectivity have been observed experimentally as a function of crystallographically exposed faces and degree of reduction. We find that the barrier for carbon-hydrogen cleavage in methoxy is similar for the pristine and defective (111), (100), and (110) surfaces. However, there are large differences in the stability of the surface intermediates on the different surfaces. The variations in experimentally observed productmore » selectivities are a consequence of the interplay between barrier controlled bond cleavage and desorption processes. Ultimately, subtle differences in activation energies for carbon-hydrogen cleavage on the different crystallographic faces of ceria could not be correlated with structural or electronic descriptors.« less
Dehydrogenation of methanol to formaldehyde catalyzed by pristine and defective ceria surfaces
Beste, Ariana; Overbury, Steven H.
2016-03-09
We have explored the dehydrogenation of methoxy on pristine and defective (111), (100), and (110) ceria surfaces with density functional methods. Methanol conversion is used as a probe reaction to understand structure sensitivity of the oxide catalysis. Differences in reaction selectivity have been observed experimentally as a function of crystallographically exposed faces and degree of reduction. We find that the barrier for carbon-hydrogen cleavage in methoxy is similar for the pristine and defective (111), (100), and (110) surfaces. However, there are large differences in the stability of the surface intermediates on the different surfaces. The variations in experimentally observed productmore » selectivities are a consequence of the interplay between barrier controlled bond cleavage and desorption processes. Ultimately, subtle differences in activation energies for carbon-hydrogen cleavage on the different crystallographic faces of ceria could not be correlated with structural or electronic descriptors.« less
Dehydrogenation of methanol to formaldehyde catalyzed by pristine and defective ceria surfaces.
Beste, Ariana; Overbury, Steven H
2016-04-21
We have explored the dehydrogenation of methoxy on pristine and defective (111), (100), and (110) ceria surfaces with density functional methods. Methanol conversion is used as a probe reaction to understand structure sensitivity of the oxide catalysis. Differences in reaction selectivity have been observed experimentally as a function of crystallographically exposed faces and degree of reduction. We find that the barrier for carbon-hydrogen cleavage in methoxy is similar for the pristine and defective (111), (100), and (110) surfaces. However, there are large differences in the stability of the surface intermediates on the different surfaces. The variations in experimentally observed product selectivities are a consequence of the interplay between barrier controlled bond cleavage and desorption processes. Subtle differences in activation energies for carbon-hydrogen cleavage on the different crystallographic faces of ceria could not be correlated with structural or electronic descriptors.
Pristine extraterrestrial material with unprecedented nitrogen isotopic variation.
Briani, Giacomo; Gounelle, Matthieu; Marrocchi, Yves; Mostefaoui, Smail; Leroux, Hugues; Quirico, Eric; Meibom, Anders
2009-06-30
Pristine meteoritic materials carry light element isotopic fractionations that constrain physiochemical conditions during solar system formation. Here we report the discovery of a unique xenolith in the metal-rich chondrite Isheyevo. Its fine-grained, highly pristine mineralogy has similarity with interplanetary dust particles (IDPs), but the volume of the xenolith is more than 30,000 times that of a typical IDP. Furthermore, an extreme continuum of N isotopic variation is present in this xenolith: from very light N isotopic composition (delta(15)N(AIR) = -310 +/- 20 per thousand), similar to that inferred for the solar nebula, to the heaviest ratios measured in any solar system material (delta(15)N(AIR) = 4,900 +/- 300 per thousand). At the same time, its hydrogen and carbon isotopic compositions exhibit very little variation. This object poses serious challenges for existing models for the origin of light element isotopic anomalies.
Guan, Shane; Lin, Tzu-Hao; Chou, Lien-Siang; Vignola, Joseph; Judge, John; Turo, Diego
2015-05-01
The underwater acoustic field is an important ecological element for many aquatic animals. This research examines the soundscape of a critically endangered Indo-Pacific humpback dolphin population in the shallow water environment off the west coast of Taiwan. Underwater acoustic recordings were conducted between late spring and late fall in 2012 at Yunlin (YL), which is close to a shipping lane, and Waisanding (WS), which is relatively pristine. Site-specific analyses were performed on the dynamics of the temporal and spectral acoustic characteristics for both locations. The results highlight the dynamics of the soundscape in two major octave bands: 150-300 Hz and 1.2-2.4 kHz. The acoustic energy in the former frequency band is mainly associated with passing container vessels near YL, while the latter frequency band is from sonic fish chorus at nighttime in both recording sites. In addition, large variation of low frequency acoustic energy throughout the study period was noticed at WS, where the water depths ranged between 1.5 and 4.5 m depending on tidal cycle. This phenomenon suggests that besides certain sound sources in the environment, the coastal soundscape may also be influenced by its local bathymetry and the dynamics of the physical environment.
Firsthand Perspective on the Microgravity Environment
NASA Technical Reports Server (NTRS)
Thomas, Donald A.
1998-01-01
Extended periods of microgravity simply cannot be created on Earth and rely on orbiting spacecraft in low earth orbit. These low microgravity levels are one of the most critical resources for most experiments being conducted aboard the space shuttle and those proposed for the International Space Station. A second critical resource for successfully conducting many of these experiments in space is the presence of human beings. Trained mission specialists and payload specialists become the eyes and ears of the scientists on the ground. In their function as in-flight technicians and "observers" they are important for reporting first hand the progress of the experiments, as well as being on call to trouble shoot malfunctioning equipment and, make necessary repairs. Unfortunately, as important as astronauts are to the successful performance of many experiments, they can be in conflict with the first goal of achieving as pristine a microgravity environment as possible. A simple astronaut sneeze has been calculated to induce a perturbation of 10(exp -5) g which may adversely affect some of the more sensitive experiments. A first hand perspective of what it is like to work in this environment and ways crewmembers can work more effectively to minimize disturbances will be discussed as well as ways that the ground can assist crewmembers to protect the microgravity environment.
Grotti, Marco; Pizzini, Sarah; Abelmoschi, Maria Luisa; Cozzi, Giulio; Piazza, Rossano; Soggia, Francesco
2016-12-01
Antarctica offers a good opportunity to investigate planetary-scale pollution and climate change, and provides baseline values for contaminants such as Trace Elements (TEs) and Persistent Organic Pollutants (POPs). Literature data on contaminant levels in the Antarctic environment indicate that long-range atmospheric transport is the primary pathway by which pollutants from surrounding continents are carried to this pristine environment. However, local contamination sources represented by the scientific stations are also not negligible. Climate change and global warming are altering the global budget of anthropogenic contaminants and their monitoring in Antarctica ecosystems is very important to protect the global environment. In this work, eighty specimens of Adamussium colbecki (Smith, 1902), a benthic Antarctic scallop, collected from 1996 to 2009 and stored in the Antarctic Environmental Specimen Bank, were analyzed to quantify TEs and POPs, including polychlorinated biphenyls (PCBs), polychlorinated naphthalenes (PCNs) and polycyclic aromatic hydrocarbons (PAHs). Metals concentrations were not affected by anthropogenic contributions, highlighting a natural accumulation with the age of the organism. Similarly, no temporal trend was found for PCNs, PCBs and PAHs. However, specimens collected during the summer 1997-98 showed enhanced concentration levels of PCBs and PAHs that could refer to a local anthropogenic source of contamination. Copyright © 2016 Elsevier Ltd. All rights reserved.
Multiple-stage structure transformation of organic-inorganic hybrid perovskite CH 3 NH 3 PbI 3
Chen, Qiong; Liu, Henan; Kim, Hui -Seon; ...
2016-09-15
In this study, by performing spatially resolved Raman and photoluminescence spectroscopy with varying excitation wavelength, density, and data acquisition parameters, we achieve a unified understanding towards the spectroscopy signatures of the organic-inorganic hybrid perovskite, transforming from the pristine state (CH 3NH 3PbI 3) to the fully degraded state (i.e., PbI 2) for samples with varying crystalline domain size from mesoscopic scale (approximately 100 nm) to macroscopic size (centimeters), synthesized by three different techniques. We show that the hybrid perovskite exhibits multiple stages of structure transformation occurring either spontaneously or under light illumination, with exceptionally high sensitivity to the illumination conditionsmore » (e.g., power, illumination time, and interruption pattern). We highlight four transformation stages (stages I-IV, with stage I being the pristine state) along either the spontaneous or photoinduced degradation path exhibiting distinctly different Raman spectroscopy features at each stage, and point out that previously reported Raman spectra in the literature reflect highly degraded structures of either stage III or stage IV. Additional characteristic optical features of partially degraded materials under the joint action of spontaneous and photodegradation are also given. This study offers reliable benchmark results for understanding the intrinsic material properties and structure transformation of this unique category of hybrid materials, and the findings are pertinently important to a wide range of potential applications where the hybrid material is expected to function in greatly different environment and light-matter interaction conditions.« less
Rull, Valentí; Vegas-Vilarrúbia, Teresa
2017-01-01
The neotropical Guayana Highlands (GH) are one of the few remaining pristine environments on Earth, and they host amazing biodiversity with a high degree endemism, especially among vascular plants. Despite the lack of direct human disturbance, GH plants and their communities are threatened with extinction from habitat loss due to global warming (GW). Geographic information systems simulations involving the entire known vascular GH flora (>2430 species) predict potential GW-driven extinctions on the order of 80% by the end of this century, including nearly half of the endemic species. These estimates and the assessment of an environmental impact value for each species led to the hierarchization of plants by their risk of habitat loss and the definition of priority conservation categories. However, the predictions assume that all species will respond to GW by migrating upward and at equal rates, which is unlikely, so current estimates should be considered preliminary and incomplete (although they represent the best that can be done with the existing information). Other potential environmental forcings (i.e., precipitation shifts, an increase in the atmospheric CO2 concentration) and idiosyncratic plant responses (i.e., resistance, phenotypic acclimation, rapid evolution) should also be considered, so detailed eco-physiological studies of the more threatened species are urgently needed. The main obstacles to developing such studies are the remoteness and inaccessibility of the GH and, especially, the difficulty in obtaining official permits for fieldwork. PMID:28179913
Rull, Valentí; Vegas-Vilarrúbia, Teresa
2017-01-01
The neotropical Guayana Highlands (GH) are one of the few remaining pristine environments on Earth, and they host amazing biodiversity with a high degree endemism, especially among vascular plants. Despite the lack of direct human disturbance, GH plants and their communities are threatened with extinction from habitat loss due to global warming (GW). Geographic information systems simulations involving the entire known vascular GH flora (>2430 species) predict potential GW-driven extinctions on the order of 80% by the end of this century, including nearly half of the endemic species. These estimates and the assessment of an environmental impact value for each species led to the hierarchization of plants by their risk of habitat loss and the definition of priority conservation categories. However, the predictions assume that all species will respond to GW by migrating upward and at equal rates, which is unlikely, so current estimates should be considered preliminary and incomplete (although they represent the best that can be done with the existing information). Other potential environmental forcings (i.e., precipitation shifts, an increase in the atmospheric CO 2 concentration) and idiosyncratic plant responses (i.e., resistance, phenotypic acclimation, rapid evolution) should also be considered, so detailed eco-physiological studies of the more threatened species are urgently needed. The main obstacles to developing such studies are the remoteness and inaccessibility of the GH and, especially, the difficulty in obtaining official permits for fieldwork.
Multiple-Stage Structure Transformation of Organic-Inorganic Hybrid Perovskite CH3NH3PbI3
NASA Astrophysics Data System (ADS)
Chen, Qiong; Liu, Henan; Kim, Hui-Seon; Liu, Yucheng; Yang, Mengjin; Yue, Naili; Ren, Gang; Zhu, Kai; Liu, Shengzhong; Park, Nam-Gyu; Zhang, Yong
2016-07-01
By performing spatially resolved Raman and photoluminescence spectroscopy with varying excitation wavelength, density, and data acquisition parameters, we achieve a unified understanding towards the spectroscopy signatures of the organic-inorganic hybrid perovskite, transforming from the pristine state (CH3NH3PbI3 ) to the fully degraded state (i.e., PbI2 ) for samples with varying crystalline domain size from mesoscopic scale (approximately 100 nm) to macroscopic size (centimeters), synthesized by three different techniques. We show that the hybrid perovskite exhibits multiple stages of structure transformation occurring either spontaneously or under light illumination, with exceptionally high sensitivity to the illumination conditions (e.g., power, illumination time, and interruption pattern). We highlight four transformation stages (stages I-IV, with stage I being the pristine state) along either the spontaneous or photoinduced degradation path exhibiting distinctly different Raman spectroscopy features at each stage, and point out that previously reported Raman spectra in the literature reflect highly degraded structures of either stage III or stage IV. Additional characteristic optical features of partially degraded materials under the joint action of spontaneous and photodegradation are also given. This study offers reliable benchmark results for understanding the intrinsic material properties and structure transformation of this unique category of hybrid materials, and the findings are pertinently important to a wide range of potential applications where the hybrid material is expected to function in greatly different environment and light-matter interaction conditions.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zodtner, H. H.
There is an interest in discovering the various peace time uses of nuclear explosives. One of the proposals is the building of harbors. There are several ports along the west coast of South America where lighterage is necessary. This implies a need for expanded harbor facilities. The problem is to find a good location for creating a harbor, and the feasibility of accomplishing this with the use of nuclear force. Feasibility includes blast effects, radiation hazards, the number of weapons needed, and economic considerations. Economic considerations include the cost of treating a harbor of sufficient depth and area, the buildingmore » of harbor facilities, and the estimated savings and advantages of the new harbor. Several meetings were held with naval personnel of the Military Liaison group at UCRL to discuss the general problems of harbors. Thirty-three different ports were given a preliminary investigation.« less
Lefebvre, Kathi A; Quakenbush, Lori; Frame, Elizabeth; Huntington, Kathy Burek; Sheffield, Gay; Stimmelmayr, Raphaela; Bryan, Anna; Kendrick, Preston; Ziel, Heather; Goldstein, Tracey; Snyder, Jonathan A; Gelatt, Tom; Gulland, Frances; Dickerson, Bobette; Gill, Verena
2016-05-01
Current climate trends resulting in rapid declines in sea ice and increasing water temperatures are likely to expand the northern geographic range and duration of favorable conditions for harmful algal blooms (HABs), making algal toxins a growing concern in Alaskan marine food webs. Two of the most common HAB toxins along the west coast of North America are the neurotoxins domoic acid (DA) and saxitoxin (STX). Over the last 20 years, DA toxicosis has caused significant illness and mortality in marine mammals along the west coast of the USA, but has not been reported to impact marine mammals foraging in Alaskan waters. Saxitoxin, the most potent of the paralytic shellfish poisoning toxins, has been well-documented in shellfish in the Aleutians and Gulf of Alaska for decades and associated with human illnesses and deaths due to consumption of toxic clams. There is little information regarding exposure of Alaskan marine mammals. Here, the spatial patterns and prevalence of DA and STX exposure in Alaskan marine mammals are documented in order to assess health risks to northern populations including those species that are important to the nutritional, cultural, and economic well-being of Alaskan coastal communities. In this study, 905 marine mammals from 13 species were sampled including; humpback whales, bowhead whales, beluga whales, harbor porpoises, northern fur seals, Steller sea lions, harbor seals, ringed seals, bearded seals, spotted seals, ribbon seals, Pacific walruses, and northern sea otters. Domoic acid was detected in all 13 species examined and had the greatest prevalence in bowhead whales (68%) and harbor seals (67%). Saxitoxin was detected in 10 of the 13 species, with the highest prevalence in humpback whales (50%) and bowhead whales (32%). Pacific walruses contained the highest concentrations of both STX and DA, with DA concentrations similar to those detected in California sea lions exhibiting clinical signs of DA toxicosis (seizures) off the coast of Central California, USA. Forty-six individual marine mammals contained detectable concentrations of both toxins emphasizing the potential for combined exposure risks. Additionally, fetuses from a beluga whale, a harbor porpoise and a Steller sea lion contained detectable concentrations of DA documenting maternal toxin transfer in these species. These results provide evidence that HAB toxins are present throughout Alaska waters at levels high enough to be detected in marine mammals and have the potential to impact marine mammal health in the Arctic marine environment. Published by Elsevier B.V.
Estrogen regulation of gene expression in the teleost fish immune system.
Burgos-Aceves, Mario Alberto; Cohen, Amit; Smith, Yoav; Faggio, Caterina
2016-11-01
Elucidating the mechanisms of estrogens-induced immunomodulation in teleost fish is of great importance due to the observed worldwide continuing decrease in pristine environments. However, little is know about the immunotoxicological consequences of exposure to these chemicals in fish, or of the mechanisms through which these effects are mediated. In this review, we summarize the results showing estrogens (natural or synthetic) acting through estrogen receptors and regulating specific target genes, also through microRNAs (miRNAs), leading to modulation of the immune functioning. The identification and characterization of miRNAs will provide new opportunities for functional genome research on teleost immune system and can also be useful when screening for novel molecule biomarkers for environmental pollution. Copyright © 2016 Elsevier Ltd. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fan, Jiwen; Rosenfeld, Daniel; Zhang, Yuwei
Aerosol-cloud interactions remain the largest uncertainty in climate projections. Ultrafine aerosol particles smaller than 50 nanometers (UAP <50) can be abundant in the troposphere, but are conventionally considered too small to affect cloud formation. However, observational evidence and numerical simulations of deep convective clouds (DCCs) over the Amazon show that DCCs forming in a low aerosol environment can develop very large vapor supersaturation because fast droplet coalescence reduces integrated droplet surface area and subsequent condensation. UAP <50 from pollution plumes that are ingested into such clouds can be activated to form additional cloud droplets on which excess supersaturation condenses andmore » forms additional cloud water and latent heating, thus intensifying convective strength. This mechanism suggests a strong anthropogenic invigoration of DCCs in previously pristine regions of the world.« less
Boyle, D G; Boyle, D B; Olsen, V; Morgan, J A T; Hyatt, A D
2004-08-09
Batrachochytrium dendrobatidis is a major pathogen of frogs worldwide, associated with declines in amphibian populations. Diagnosis of chytridiomycosis to date has largely relied upon histological and immunohistochemical examination of toe clips. This technique is invasive and insensitive particularly at early stages of infection when treatment may be possible. We have developed a real-time PCR Taqman assay that can accurately detect and quantify one zoospore in a diagnostic sample. This assay will assist the early detection of B. dendrobatidis in both captive and wild populations, with a high degree of sensitivity and specificity, thus facilitating treatment and protection of endangered populations, monitoring of pristine environments and preventing further global spread via amphibian trade.
Detection of pristine gas two billion years after the Big Bang.
Fumagalli, Michele; O'Meara, John M; Prochaska, J Xavier
2011-12-02
In the current cosmological model, only the three lightest elements were created in the first few minutes after the Big Bang; all other elements were produced later in stars. To date, however, heavy elements have been observed in all astrophysical environments. We report the detection of two gas clouds with no discernible elements heavier than hydrogen. These systems exhibit the lowest heavy-element abundance in the early universe, and thus are potential fuel for the most metal-poor halo stars. The detection of deuterium in one system at the level predicted by primordial nucleosynthesis provides a direct confirmation of the standard cosmological model. The composition of these clouds further implies that the transport of heavy elements from galaxies to their surroundings is highly inhomogeneous.
Polycyclic aromatic hydrocarbon-DNA adducts in Beluga whales from the Arctic
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mathieu, A.; Payne, J.F.; Fancey, L.L.
1997-09-01
The Arctic is still relatively pristine in nature, but it is also vulnerable to pollution because contaminants originating from midlatitudes are transported to the Arctic by atmospheric processes, ocean currents, and river. Recognition of this fact of Arctic vulnerability has resulted in a Declaration on the Protection of the Arctic Environment by eight Arctic countries. A manifest aim of this declaration is to develop an Arctic Monitoring and Assessment Program. We report here on the presence of measurable levels of polycyclic aromatic hydrocarbon-DNA adducts, including relatively high levels in Arctic beluga (Delphinapterus leucas). These results lend support to the valuemore » of developing biological assessment programs for Arctic wildlife. 15 refs., 1 tab.« less
Páez-Osuna, F; Calderón-Campuzano, M F; Soto-Jiménez, M F; Ruelas-Inzunza, J
2011-06-01
Mercury concentrations were assessed in the sea turtle Lepidochelys olivacea from a nesting colony of Oaxaca, Mexico; 25 female turtles were sampled, a total of 250 eggs were collected during the season 2005-2006. Higher concentrations were found in yolk fraction, while in blood and albumen mean levels were below of 0.0010μg g(-1) dry wt. On the basis of one nesting season, the maternal transfer of Hg via eggs-laying was estimated in 2.0±1.1%. According to international norms, the health of this population and its habitats is acceptable for Hg and corresponds to baseline levels of a nearly pristine environment. Copyright © 2011 Elsevier Ltd. All rights reserved.
33 CFR 110.130 - Bar Harbor, Maine.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Bar Harbor, Maine. 110.130... ANCHORAGE REGULATIONS Anchorage Grounds § 110.130 Bar Harbor, Maine. (a) Anchorage grounds. (1) Anchorage “A” is that portion of Frenchman Bay, Bar Harbor, ME enclosed by a rhumb line connecting the following...
33 CFR 110.38 - Edgartown Harbor, Mass.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Edgartown Harbor, Mass. 110.38 Section 110.38 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY ANCHORAGES ANCHORAGE REGULATIONS Special Anchorage Areas § 110.38 Edgartown Harbor, Mass. An area in the inner harbor...
33 CFR 110.38 - Edgartown Harbor, Mass.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Edgartown Harbor, Mass. 110.38 Section 110.38 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY ANCHORAGES ANCHORAGE REGULATIONS Special Anchorage Areas § 110.38 Edgartown Harbor, Mass. An area in the inner harbor...
33 CFR 110.38 - Edgartown Harbor, Mass.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Edgartown Harbor, Mass. 110.38 Section 110.38 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY ANCHORAGES ANCHORAGE REGULATIONS Special Anchorage Areas § 110.38 Edgartown Harbor, Mass. An area in the inner harbor...
33 CFR 110.38 - Edgartown Harbor, Mass.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Edgartown Harbor, Mass. 110.38 Section 110.38 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY ANCHORAGES ANCHORAGE REGULATIONS Special Anchorage Areas § 110.38 Edgartown Harbor, Mass. An area in the inner harbor...
33 CFR 110.38 - Edgartown Harbor, Mass.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Edgartown Harbor, Mass. 110.38 Section 110.38 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY ANCHORAGES ANCHORAGE REGULATIONS Special Anchorage Areas § 110.38 Edgartown Harbor, Mass. An area in the inner harbor...
76 FR 32071 - Safety Zone; Conneaut Festival Fireworks, Conneaut Harbor, Conneaut, OH
Federal Register 2010, 2011, 2012, 2013, 2014
2011-06-03
...-AA00 Safety Zone; Conneaut Festival Fireworks, Conneaut Harbor, Conneaut, OH AGENCY: Coast Guard, DHS... Conneaut Harbor, Conneaut, OH for the Conneaut Festival Fireworks. This zone is intended to restrict vessels from a portion of Conneaut Harbor, Conneaut, OH during the Conneaut Festival Fireworks on July 3...
76 FR 34865 - Safety Zone; Rochester Harbor Festival, Genesee River, Rochester, NY
Federal Register 2010, 2011, 2012, 2013, 2014
2011-06-15
...-AA00 Safety Zone; Rochester Harbor Festival, Genesee River, Rochester, NY AGENCY: Coast Guard, DHS... Genesee River, Rochester, NY for the Rochester Harbor Festival fireworks. This zone is intended to restrict vessels from the mouth of the Genesee River in Rochester during the Rochester Harbor Festival...
Federal Register 2010, 2011, 2012, 2013, 2014
2010-08-24
... DEPARTMENT OF THE INTERIOR National Park Service Boston Harbor Islands National Recreation Area..., Boston Harbor Islands National Recreation Area. ACTION: Notice of meeting. SUMMARY: Notice is hereby given that a meeting of the Boston Harbor Islands National Recreation Area Advisory Council will be held...
Federal Register 2010, 2011, 2012, 2013, 2014
2010-12-16
... Operation Regulation; Gulf Intracoastal Waterway, New Orleans Harbor, Inner Harbor Navigation Canal, New Orleans, Orleans Parish, LA AGENCY: Coast Guard, DHS. ACTION: Notice of temporary deviation from... Harvey Lock), at New Orleans, Orleans Parish, Louisiana. This deviation is necessary to adjust the...
78 FR 18479 - Drawbridge Operation Regulations; Inner Harbor Navigation Canal, New Orleans, LA
Federal Register 2010, 2011, 2012, 2013, 2014
2013-03-27
... Operation Regulations; Inner Harbor Navigation Canal, New Orleans, LA AGENCY: Coast Guard, DHS. ACTION... across the Inner Harbor Navigation Canal, mile 4.6, at New Orleans, Louisiana. This deviation is... Seabrook Highway crossing the Inner Harbor Navigation Canal, mile 4.6, in New Orleans, Louisiana. The...
32 CFR 765.6 - Regulations for Pearl Harbor, Hawaii.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 32 National Defense 5 2010-07-01 2010-07-01 false Regulations for Pearl Harbor, Hawaii. 765.6... RULES RULES APPLICABLE TO THE PUBLIC § 765.6 Regulations for Pearl Harbor, Hawaii. The Commander, U.S. Naval Base, Pearl Harbor, Hawaii, is responsible for prescribing and enforcing such rules and...
78 FR 42016 - Safety Zone; Discovery World Fireworks, Milwaukee Harbor, Milwaukee, WI
Federal Register 2010, 2011, 2012, 2013, 2014
2013-07-15
...-AA00 Safety Zone; Discovery World Fireworks, Milwaukee Harbor, Milwaukee, WI AGENCY: Coast Guard, DHS... Milwaukee Harbor due to 4 fireworks displays at Discovery World Pier. This safety zone is necessary to... entitled, ``Safety Zone; Discovery World Fireworks, Milwaukee Harbor, Milwaukee, Wisconsin'' in the Federal...
Koskey, Amber M.; Fisher, Jenny C.; Traudt, Mary F.; Newton, Ryan J.
2014-01-01
Gulls are prevalent in beach environments and can be a major source of fecal contamination. Gulls have been shown to harbor a high abundance of fecal indicator bacteria (FIB), such as Escherichia coli and enterococci, which can be readily detected as part of routine beach monitoring. Despite the ubiquitous presence of gull fecal material in beach environments, the associated microbial community is relatively poorly characterized. We generated comprehensive microbial community profiles of gull fecal samples using Roche 454 and Illumina MiSeq platforms to investigate the composition and variability of the gull fecal microbial community and to measure the proportion of FIB. Enterococcaceae and Enterobacteriaceae were the two most abundant families in our gull samples. Sequence comparisons between short-read data and nearly full-length 16S rRNA gene clones generated from the same samples revealed Catellicoccus marimammalium as the most numerous taxon among all samples. The identification of bacteria from gull fecal pellets cultured on membrane-Enterococcus indoxyl-β-d-glucoside (mEI) plates showed that the dominant sequences recovered in our sequence libraries did not represent organisms culturable on mEI. Based on 16S rRNA gene sequencing of gull fecal isolates cultured on mEI plates, 98.8% were identified as Enterococcus spp., 1.2% were identified as Streptococcus spp., and none were identified as C. marimammalium. Illumina deep sequencing indicated that gull fecal samples harbor significantly higher proportions of C. marimammalium 16S rRNA gene sequences (>50-fold) relative to typical mEI culturable Enterococcus spp. C. marimammalium therefore can be confidently utilized as a genetic marker to identify gull fecal pollution in the beach environment. PMID:24242244
Demopoulos, Amanda W.J.; Foster, Ann M.; Jones, Michal L.; Gualtieri, Daniel J.
2011-01-01
The Geospatial Characteristics GeoPDF of Florida's Coastal and Offshore Environments is a comprehensive collection of geospatial data describing the political boundaries and natural resources of Florida. This interactive map provides spatial information on bathymetry, sand resources, coastal habitats, artificial reefs, shipwrecks, dumping grounds, and harbor obstructions. The map should be useful to coastal resource managers and others interested in marine habitats and submerged obstructions of Florida's coastal region. In particular, as oil and gas explorations continue to expand, the map may be used to explore information regarding sensitive areas and resources in the State of Florida. Users of this geospatial database will have access to synthesized information in a variety of scientific disciplines concerning Florida's coastal zone. This powerful tool provides a one-stop assembly of data that can be tailored to fit the needs of many natural resource managers. The map was originally developed to assist the Bureau of Ocean Energy Management, Regulation, and Enforcement (BOEMRE) and coastal resources managers with planning beach restoration projects. The BOEMRE uses a systematic approach in planning the development of submerged lands of the Continental Shelf seaward of Florida's territorial waters. Such development could affect the environment. BOEMRE is required to ascertain the existing physical, biological, and socioeconomic conditions of the submerged lands and estimate the impact of developing these lands. Data sources included the National Oceanic and Atmospheric Administration, BOEMRE, Florida Department of Environmental Protection, Florida Geographic Data Library, Florida Fish and Wildlife Conservation Commission, Florida Natural Areas Inventory, and the State of Florida, Bureau of Archeological Research. Federal Geographic Data Committee (FGDC) compliant metadata are provided as attached xml files for all geographic information system (GIS) layers.
Isolation and Characterization of Stenotrophomonas maltophilia Isolates from a Brazilian Hospital.
Gallo, Stephanie W; Figueiredo, Thomaz P; Bessa, Marjo C; Pagnussatti, Vany E; Ferreira, Carlos A S; Oliveira, Sílvia D
2016-12-01
Stenotrophomonas maltophilia is an emerging nosocomial pathogen responsible for several infections in immunocompromised patients. To characterize the antimicrobial resistance and virulence potential of this microorganism in a Brazilian hospital, a total of 936 samples were collected from a nosocomial environment and medical devices, and 100 isolates from clinical specimens were obtained in the same hospital. S. maltophilia was found in 3% of the samples collected, especially in bed rails from hospital rooms. The smf-1 gene was detected in 23% and 42% of the clinical and hospital environment isolates, respectively, and almost all (96.8%) isolates that harbored smf-1 were able to form biofilm. All isolates were susceptible to minocycline and chloramphenicol, and the majority of isolates were susceptible to levofloxacin. High resistance to ceftazidime was detected in both groups of isolates. Resistance to trimethoprim-sulfamethoxazole (TMP/SMX) was found in 14.8% of the isolates. All TMP/SMX-resistant isolates presented class 1 integron and sul1 gene, and 47.4% of them also harbored the sul2 gene, which was inserted into a 7.3 kb plasmid. Genetic relatedness among the isolates was evaluated by enterobacterial repetitive intergenic consensus-PCR, and eight genetic patterns were identified. One pattern comprised 54.7% of isolates and was spread among clinical and environmental (furniture and medical devices) sources. The presence of S. maltophilia in the hospital environment indicates that it can act as a reservoir of this microorganism. In addition, hospital isolates resistant to TMP/SMX showed that the genetic determinants were present in mobile elements, which can constitute great concern, as it may indicate a tendency to spread.
33 CFR 162.165 - Buffalo and Rochester Harbors, New York.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Buffalo and Rochester Harbors, New York. 162.165 Section 162.165 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND... and Rochester Harbors, New York. In Buffalo and Rochester Harbors, no vessel may exceed 6 miles per...
33 CFR 100.113 - Provincetown Harbor Swim for Life, Provincetown, MA.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Provincetown Harbor Swim for Life... SECURITY REGATTAS AND MARINE PARADES SAFETY OF LIFE ON NAVIGABLE WATERS § 100.113 Provincetown Harbor Swim for Life, Provincetown, MA. (a) Regulated Area. All waters of Provincetown Harbor within 200 feet of...
77 FR 27666 - Proposed Amendment of Class E Airspace; Bar Harbor, ME
Federal Register 2010, 2011, 2012, 2013, 2014
2012-05-11
...-1366; Airspace Docket No. 11-ANE-13] Proposed Amendment of Class E Airspace; Bar Harbor, ME AGENCY... action proposes to amend Class E Airspace at Bar Harbor, ME, as the Surry Non-Directional Radio Beacon... Airport, Bar Harbor, ME. Airspace reconfiguration is necessary due to the decommissioning of the Surry NDB...
33 CFR 80.1136 - Moss Landing Harbor, CA.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Moss Landing Harbor, CA. 80.1136... NAVIGATION RULES COLREGS DEMARCATION LINES Pacific Coast § 80.1136 Moss Landing Harbor, CA. A line drawn from the seaward extremity of the pier located 0.3 mile south of Moss Landing Harbor Entrance to the...
33 CFR 80.1136 - Moss Landing Harbor, CA.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Moss Landing Harbor, CA. 80.1136... NAVIGATION RULES COLREGS DEMARCATION LINES Pacific Coast § 80.1136 Moss Landing Harbor, CA. A line drawn from the seaward extremity of the pier located 0.3 mile south of Moss Landing Harbor Entrance to the...
33 CFR 165.14-1414 - Safety Zones; Hawaiian Islands Commercial Harbors; HI.
Code of Federal Regulations, 2014 CFR
2014-07-01
... harbors, or all of these harbors, dependent upon details in the tsunami warning. These safety zones extend... period. Paragraph (b) of this section will be enforced when a tsunami warning has been issued for the... Coast Guard's Homeport Web site. Following the passage of the tsunami or tsunami threat and harbor...
33 CFR 110.9 - Wells Harbor, Maine.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Wells Harbor, Maine. 110.9... ANCHORAGE REGULATIONS Special Anchorage Areas § 110.9 Wells Harbor, Maine. (a) Anchorage “A”. All of the... approximately 5,800 sq. yards, encompassing the central portion of Wells Harbor. (b) Anchorage “B”. All of the...
33 CFR 110.9 - Wells Harbor, Maine.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Wells Harbor, Maine. 110.9... ANCHORAGE REGULATIONS Special Anchorage Areas § 110.9 Wells Harbor, Maine. Link to an amendment published at..., encompassing the central portion of Wells Harbor. (b) Anchorage “B”. All of the waters enclosed by a line...
33 CFR 117.272 - Boot Key Harbor.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Boot Key Harbor. 117.272 Section 117.272 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Florida § 117.272 Boot Key Harbor. The draw of the Boot Key Harbor drawbridge, mile 0.13, between...
46 CFR 45.181 - Load line exemption requirements for the Burns Harbor and Milwaukee routes.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 46 Shipping 2 2014-10-01 2014-10-01 false Load line exemption requirements for the Burns Harbor... line exemption requirements for the Burns Harbor and Milwaukee routes. Barges operating on the Burns... addresses and telephone numbers); (3) Service route (Milwaukee and/or Burns Harbor); (4) Design type...
46 CFR 45.181 - Load line exemption requirements for the Burns Harbor and Milwaukee routes.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 46 Shipping 2 2013-10-01 2013-10-01 false Load line exemption requirements for the Burns Harbor... line exemption requirements for the Burns Harbor and Milwaukee routes. Barges operating on the Burns... addresses and telephone numbers); (3) Service route (Milwaukee and/or Burns Harbor); (4) Design type...
46 CFR 45.181 - Load line exemption requirements for the Burns Harbor and Milwaukee routes.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 46 Shipping 2 2012-10-01 2012-10-01 false Load line exemption requirements for the Burns Harbor... line exemption requirements for the Burns Harbor and Milwaukee routes. Barges operating on the Burns... addresses and telephone numbers); (3) Service route (Milwaukee and/or Burns Harbor); (4) Design type...
46 CFR 45.181 - Load line exemption requirements for the Burns Harbor and Milwaukee routes.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 46 Shipping 2 2011-10-01 2011-10-01 false Load line exemption requirements for the Burns Harbor... line exemption requirements for the Burns Harbor and Milwaukee routes. Barges operating on the Burns... addresses and telephone numbers); (3) Service route (Milwaukee and/or Burns Harbor); (4) Design type...
46 CFR 45.181 - Load line exemption requirements for the Burns Harbor and Milwaukee routes.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 46 Shipping 2 2010-10-01 2010-10-01 false Load line exemption requirements for the Burns Harbor... line exemption requirements for the Burns Harbor and Milwaukee routes. Barges operating on the Burns... (Milwaukee and/or Burns Harbor); (4) Design type (covered/uncovered hopper, deck, etc.); (5) External...
2003-06-04
KENNEDY SPACE CENTER, FLA. - At Port Canaveral, the Pressurized Module of the Japanese Experiment Module (JEM) is lifted out of the ship’s cargo hold. It will be loaded onto the truck bed in the background for transfer to KSC’s Space Station Processing Facility. The container transport ship carrying JEM departed May 2 from Yokohama Harbor in Japan for the voyage to the United States. The National Space Development Agency of Japan (NASDA) developed the laboratory at the Tsukuba Space Center near Tokyo. The Pressurized Module is the first element of the JEM, named "Kibo" (Hope), to be delivered to KSC. The JEM is Japan's primary contribution to the Station. It will enhance the unique research capabilities of the orbiting complex by providing an additional environment for astronauts to conduct science experiments. The JEM also includes an exposed facility (platform) for space environment experiments, a robotic manipulator system, and two logistics modules. The various JEM components will be assembled in space over the course of three Shuttle missions.
Ganju, Neil K.; Dickhudt, Patrick J.; Thomas, Jennifer A.; Borden, Jonathan; Sherwood, Christopher R.; Montgomery, Ellyn T.; Twomey, Erin R.; Martini, Marinna A.
2011-01-01
This data report presents oceanographic and water-quality observations made at six locations in West Falmouth Harbor and Buzzards Bay, Massachusetts, from August 2009 to September 2010. Both Buzzards Bay and West Falmouth Harbor are estuarine embayments; the input of freshwater on the eastern margin of Buzzards Bay adjacent to Cape Cod and West Falmouth Harbor is largely due to groundwater. In West Falmouth Harbor, the groundwater that seeps into the harbor is characterized by relatively high levels of nitrate. This high nitrate load has modified the ecology of the harbor (Howes and others, 2006) and may be a significant source of nitrate to Buzzards Bay during seasons with low biological nitrate uptake. The U.S. Geological Survey undertook these measurements to improve understanding of circulation, residence time, and water quality in the harbor and bay. We set up and monitored multiple sites in both Buzzards Bay and West Falmouth Harbor, measuring depth, water velocity,salinity, pH, dissolved oxygen, chlorophyll-a, and nitrate concentration. In this report we present the processed time-series data at these locations and provide access to the data and metadata. The results will be used to understand circulation mechanisms and verify numerical models of hydrodynamics and biogeochemistry.
Barnert, Elizabeth S; Abrams, Susan; Azzi, Veronica F; Ryan, Gery; Brook, Robert; Chung, Paul J
2016-01-01
Several states have recently enacted "Safe Harbor" laws to redirect child victims of commercial sexual exploitation and child sex trafficking from the criminal justice system and into the child welfare system. No comprehensive studies of Safe Harbor law implementation exist. The nine state Safe Harbor laws enacted by 2012 were analyzed to guide state legislators, health professionals, law enforcement agents, child welfare providers, and other responders to the commercial sexual exploitation of children on the development and implementation of state Safe Harbor laws. The authors conducted 32 semi-structured interviews with Safe Harbor experts in these states. Participants conveyed that Safe Harbor legislation signified a critical paradigm shift, treating commercially sexually exploited youth not as criminals but as vulnerable children in need of services. However, Safe Harbor legislation varied widely and significant gaps in laws exist. Such laws alone were considered insufficient without adequate funding for necessary services. As a result, many well-meaning providers were going around the Safe Harbor laws by continuing to incarcerate commercially sexually exploited youth in the juvenile justice system regardless of Safe Harbor laws in place. This was done, to act, in their view, in what was the best interest of the victimized children. With imperfect laws and implementation, these findings suggest an important role for local and state responders to act together to protect victims from unnecessary criminalization and potential further traumatization. Published by Elsevier Ltd.
Liu, Fei; Jang, Min-Ho; Ha, Hyun Dong; Kim, Je-Hyung; Cho, Yong-Hoon; Seo, Tae Seok
2013-07-19
Pristine graphene quantum dots and graphene oxide quantum dots are synthesized by chemical exfoliation from the graphite nanoparticles with high uniformity in terms of shape (circle), size (less than 4 nm), and thickness (monolayer). The origin of the blue and green photoluminescence of GQDs and GOQDs is attributed to intrinsic and extrinsic energy states, respectively. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Xie, Lianyan; Dou, Yi; Zhou, Kaixin; Chen, Yue; Han, Lizhong; Guo, Xiaokui; Sun, Jingyong
2017-01-01
Objectives: To describe the genetic environment, transferability, and antibiotic susceptibility of one clinical Klebsiella pneumoniae isolate harboring both bla OXA-48 and bla NDM-1 on different plasmids from a Chinese hospital. Methods: The isolate was subjected to antimicrobial susceptibility testing and multilocus sequence typing using Etest and PCR. The plasmids harboring bla OXA-48 and bla NDM-1 were analyzed through conjugation experiments, S1-nuclease pulsed-field gel electrophoresis, and hybridization with specific probes. Plasmid DNA was sequenced using Pacbio RS II and annotated using RAST. Results: K. pneumoniae RJ119, carrying both bla OXA-48 and bla NDM-1 , was resistant to almost all carbapenems, cephalosporins, fluoroquinolone, and aminoglycosides and belonged to ST307. bla OXA-48 was located on a 61,748-bp IncL/M conjugative plasmid, which displayed overall nucleotide identity (99%) to pKPN-E1-Nr.7. bla NDM-1 was located on a 335,317-bp conjugative plasmid, which was a fusion of a bla NDM-1 -harboring InA/C plasmid pNDM-US (140,825 bp, 99% identity) and an IncFIB plasmid pKPN-c22 (178,563 bp, 99% identity). The transconjugant RJ119-1 harboring bla NDM-1 was susceptible to carbapenem, and there was an insertion of IS 10 into the bla NDM-1 gene. Conclusion: This is the first report of the coexistence of bla OXA-48 and bla NDM-1 in one K. pneumoniae clinical isolate in China. OXA-48 in RJ119 contributed to the majority to its high resistance to carbapenems, whereas NDM-1 remained unexpressed, most likely due to the insertion of IS 10 . Our results provide new insight for the relationship between genetic diagnosis and clinical treatment. They also indicate that increased surveillance of bla OXA-48 is urgently needed in China.
Luo, Xin; Jiao, Jiu Jimmy
2016-10-01
Multiple tracers, including radium quartet, (222)Rn and silica are used to quantify submarine groundwater discharge (SGD) into Tolo Harbor, Hong Kong in 2005 and 2011. Five geotracer models based on the end member model of (228)Ra and salinity and mass balance models of (226)Ra, (228)Ra, (222)Rn, and silica were established and all the models lead to an estimate of the SGD rate of the same order of magnitude. In 2005 and 2011, respectively, the averaged SGD based on these models is estimated to be ≈ 5.42 cm d(-1) and ≈2.66 cm d(-1), the SGD derived DIN loadings to be 3.5 × 10(5) mol d(-1) and 1.5 × 10(5) mol d(-1), and DIP loadings to be 6.2 × 10(3) mol d(-1) and 1.1 × 10(3) mol d(-1). Groundwater borne nutrients are 1-2 orders of magnitude larger than other nutrient sources and the interannual variation of nutrient concentration in the embayment is more influenced by the SGD derived loadings. Annual DIP concentrations in the harbor water is positively correlated with the precipitation and annual mean tidal range, and negatively correlated with evapotranspiration from 2000 to 2013. Climatologically driven SGD variability alters the SGD derived DIP loadings in this phosphate limited environment and may be the causative factor of interannual variability of red tide outbreaks from 2000 to 2013. Finally, a conceptual model is proposed to characterize the response of red tide outbreaks to climatological factors linked by SGD. The findings from this study shed light on the prediction of red tide outbreaks and coastal management of Tolo Harbor and similar coastal embayments elsewhere. Copyright © 2016 Elsevier Ltd. All rights reserved.
Kittinger, Clemens; Lipp, Michaela; Folli, Bettina; Kirschner, Alexander; Baumert, Rita; Galler, Herbert; Grisold, Andrea J; Luxner, Josefa; Weissenbacher, Melanie; Farnleitner, Andreas H; Zarfel, Gernot
2016-01-01
In a clinical setting it seems to be normal these days that a relevant proportion or even the majority of different bacterial species has already one or more acquired antibiotic resistances. Unfortunately, the overuse of antibiotics for livestock breeding and medicine has also altered the wild-type resistance profiles of many bacterial species in different environmental settings. As a matter of fact, getting in contact with resistant bacteria is no longer restricted to hospitals. Beside food and food production, the aquatic environment might also play an important role as reservoir and carrier. The aim of this study was the assessment of the resistance patterns of Escherichia coli and Klebsiella spp. out of surface water without prior enrichment and under non-selective culture conditions (for antibiotic resistance). In addition, the presence of clinically important extended spectrum beta lactamase (ESBL) and carbapenmase harboring Enterobacteriaceae should be investigated. During Joint Danube Survey 3 (2013), water samples were taken over the total course of the River Danube. Resistance testing was performed for 21 different antibiotics. Samples were additionally screened for ESBL or carbapenmase harboring Enterobacteriaceae. 39% of all isolated Escherichia coli and 15% of all Klebsiella spp. from the river Danube had at least one acquired resistance. Resistance was found against all tested antibiotics except tigecycline. Taking a look on the whole stretch of the River Danube the proportion of multiresistances did not differ significantly. In total, 35 ESBL harboring Enterobacteriaceae, 17 Escherichia coli, 13 Klebsiella pneumoniae and five Enterobacter spp. were isolated. One Klebsiella pneumoniae harboring NMD-1 carbapenmases and two Enterobacteriaceae with KPC-2 could be identified. Human generated antibiotic resistance is very common in E. coli and Klebsiella spp. in the River Danube. Even isolates with resistance patterns normally associated with intensive care units are present.
Singh, Kiran Pal; Bhattacharjya, Dhrubajyoti; Razmjooei, Fatemeh; Yu, Jong-Sung
2016-01-01
In the race of gaining higher energy density, carbon’s capacity to retain power density is generally lost due to defect incorporation and resistance increment in carbon electrode. Herein, a relationship between charge carrier density/charge movement and supercapacitance performance is established. For this purpose we have incorporated the most defect-free pristine graphene into defective/sacrificial graphene oxide. A unique co-solvent-based technique is applied to get a homogeneous suspension of single to bi-layer graphene and graphene oxide. This suspension is then transformed into a 3D composite structure of pristine graphene sheets (GSs) and defective N-doped reduced graphene oxide (N-RGO), which is the first stable and homogenous 3D composite between GS and RGO to the best of our knowledge. It is found that incorporation of pristine graphene can drastically decrease defect density and thus decrease relaxation time due to improved associations between electrons in GS and ions in electrolyte. Furthermore, N doping is implemented selectively only on RGO and such doping is shown to improve the charge carrier density of the composite, which eventually improves the energy density. After all, the novel 3D composite structure of N-RGO and GS greatly improves energy and power density even at high current density (20 A/g). PMID:27530441
NASA Astrophysics Data System (ADS)
Ouyang, Tianhong; Qian, Zhao; Ahuja, Rajeev; Liu, Xiangfa
2018-05-01
The optimized atomic structures, energetics and electronic structures of toxic gas CO adsorption systems on pristine, C-doped and N-vacancy defected h-AlN nanosheets respectively have been investigated using Density functional theory (DFT-D2 method) to explore their potential gas detection or sensing capabilities. It is found that both the C-doping and the N-vacancy defect improve the CO adsorption energies of AlN nanosheet (from pure -3.847 eV to -5.192 eV and -4.959 eV). The absolute value of the system band gap change induced by adsorption of CO can be scaled up to 2.558 eV or 1.296 eV after C-doping or N-vacancy design respectively, which is evidently larger than the value of 0.350 eV for pristine material and will benefit the robustness of electronic signals in potential gas detection. Charge transfer mechanisms between CO and the AlN nanosheet have been presented by the Bader charge and differential charge density analysis to explore the deep origin of the underlying electronic structure changes. This theoretical study is proposed to predict and understand the CO adsorption properties of the pristine and defected h-AlN nanosheets and would help to guide experimentalists to develop better AlN-based two-dimensional materials for efficient gas detection or sensing applications in the future.
Cr2O3 nanoparticle-functionalized WO3 nanorods for ethanol gas sensors
NASA Astrophysics Data System (ADS)
Choi, Seungbok; Bonyani, Maryam; Sun, Gun-Joo; Lee, Jae Kyung; Hyun, Soong Keun; Lee, Chongmu
2018-02-01
Pristine WO3 nanorods and Cr2O3-functionalized WO3 nanorods were synthesized by the thermal evaporation of WO3 powder in an oxidizing atmosphere, followed by spin-coating of the nanowires with Cr2O3 nanoparticles and thermal annealing in an oxidizing atmosphere. Scanning electron microscopy was used to examine the morphological features and X-ray diffraction was used to study the crystallinity and phase formation of the synthesized nanorods. Gas sensing tests were performed at different temperatures in the presence of test gases (ethanol, acetone, CO, benzene and toluene). The Cr2O3-functionalized WO3 nanorods sensor showed a stronger response to these gases relative to the pristine WO3 nanorod sensor. In particular, the response of the Cr2O3-functionalized WO3 nanorods sensor to 200 ppm ethanol gas was 5.58, which is approximately 4.4 times higher that of the pristine WO3 nanorods sensor. Furthermore, the Cr2O3-functionalized WO3 nanorods sensor had a shorter response and recovery time. The pristine WO3 nanorods had no selectivity toward ethanol gas, whereas the Cr2O3-functionalized WO3 nanorods sensor showed good selectivity toward ethanol. The gas sensing mechanism of the Cr2O3-functionalized WO3 nanorods sensor toward ethanol is discussed in detail.
The evolution of machining-induced surface of single-crystal FCC copper via nanoindentation
NASA Astrophysics Data System (ADS)
Zhang, Lin; Huang, Hu; Zhao, Hongwei; Ma, Zhichao; Yang, Yihan; Hu, Xiaoli
2013-05-01
The physical properties of the machining-induced new surface depend on the performance of the initial defect surface and deformed layer in the subsurface of the bulk material. In this paper, three-dimensional molecular dynamics simulations of nanoindentation are preformed on the single-point diamond turning surface of single-crystal copper comparing with that of pristine single-crystal face-centered cubic copper. The simulation results indicate that the nucleation of dislocations in the nanoindentation test on the machining-induced surface and pristine single-crystal copper is different. The dislocation embryos are gradually developed from the sites of homogeneous random nucleation around the indenter in the pristine single-crystal specimen, while the dislocation embryos derived from the vacancy-related defects are distributed in the damage layer of the subsurface beneath the machining-induced surface. The results show that the hardness of the machining-induced surface is softer than that of pristine single-crystal copper. Then, the nanocutting simulations are performed along different crystal orientations on the same crystal surface. It is shown that the crystal orientation directly influences the dislocation formation and distribution of the machining-induced surface. The crystal orientation of nanocutting is further verified to affect both residual defect generations and their propagation directions which are important in assessing the change of mechanical properties, such as hardness and Young's modulus, after nanocutting process.
NASA Astrophysics Data System (ADS)
Kashyap, Manish K.; Paudyal, D.; Harmon, B. N.
In the present study, we have performed ab-initio simulations of sp-element defect in ZnCdTe2-xSex (x =0.625) chalcopyrite to check the tuning of band gap as compared to the pristine case. The exchange and correlation (XC) effects are taken into account by an orbital independent modified Becke-Johnson (mBJ) potential as coupled with Local Density Approximation (LDA) for these calculations. The calculated energy band structures show a direct band gap at the point in the brillouin zone for the pristine as well as the defected case and the band gap decreases with inclusion of sp-disorder. The imaginary dielectric function predicts the optical band gap of pristine ZnCdTe2 very close to the experimental value and the results are in reasonable agreement without applying any scissor operator. With inclusion of sp-element defect, the optical spectra is tuned to optimal region, suitable for photovoltaics. It is apparent that mBJ functional is well suited for calculating electronic structure of pristine as well as defected ZnCdTe2chalcopyrite. MKK acknowledges financial support from UGC, India in the form of RAMAN Post-doctoral fellowship. This work at Ames Laboratory was supported by the DOE, Office of Basic Energy Sciences, Materials Sciences Division under contract No. DE-AC02-07CH11358.
Hughes, Stephanie N; Greig, Denise J; Miller, Woutrina A; Byrne, Barbara A; Gulland, Frances M D; Harvey, James T
2013-05-01
Given their coastal site fidelity and opportunistic foraging behavior, harbor seals (Phoca vitulina) may serve as sentinels for coastal ecosystem health. Seals using urbanized coastal habitat can acquire enteric bacteria, including Vibrio that may affect their health. To understand Vibrio dynamics in seals, demographic and environmental factors were tested for predicting potentially virulent Vibrio in free-ranging and stranded Pacific harbor seals (Phoca vitulina richardii) off California. Vibrio prevalence did not vary with season and was greater in free-ranging seals (29 %, n = 319) compared with stranded seals (17 %, n = 189). Of the factors tested, location, turbidity, and/or salinity best predicted Vibrio prevalence in free-ranging seals. The relationship of environmental factors with Vibrio prevalence differed by location and may be related to oceanographic or terrestrial contributions to water quality. Vibrio parahaemolyticus, Vibrio alginolyticus, and Vibrio cholerae were observed in seals, with V. cholerae found almost exclusively in stranded pups and yearlings. Additionally, virulence genes (trh and tdh) were detected in V. parahaemolyticus isolates. Vibrio cholerae isolates lacked targeted virulence genes, but were hemolytic. Three out of four stranded pups with V. parahaemolyticus (trh+ and/or tdh+) died in rehabilitation, but the role of Vibrio in causing mortality is unclear, and Vibrio expression of virulence genes should be investigated. Considering that humans share the environment and food resources with seals, potentially virulent Vibrio observed in seals also may be of concern to human health.
Fenton, Heather; Daoust, Pierre-Yves; Forzán, María J; Vanderstichel, Raphaël V; Ford, John K B; Spaven, Lisa; Lair, Stéphane; Raverty, Stephen
2017-01-24
There is increasing public interest in the overall health of the marine environment. Harbor porpoises Phocoena phocoena have a coastal distribution, and stranded animals function as sentinels for population and ecosystem health. The goal of this retrospective study was to join datasets from the western Atlantic and eastern Pacific coasts of Canada to investigate causes of morbidity and mortality in this species. A total of 241 necropsy records were reviewed including 147 (61%) from the Pacific region and 94 (39%) from the Atlantic region from 1988 to 2011. A cause of death could be determined with confidence in 118 (49%) of these cases. Of these 118 cases, the leading cause of mortality for both regions, together and separately, was infectious disease. In the Pacific region, this was followed by traumatic and anthropogenic causes, whereas in the Atlantic region, it was followed by emaciation/starvation, mortality of dependent calves, and anthropogenic causes. Pathogens of potential zoonotic significance or indicative of environmental contamination, e.g. Salmonella sp. and Cryptococcus gattii, were identified. Numerous parasitic species were observed within the lungs, liver, stomach, middle ear, and subcutaneous tissues, although they were usually interpreted as incidental findings. Anthropogenic causes may be underrepresented as they are notoriously difficult to diagnose with certainty, thereby making up a proportion of the 'unknown causes of death' (51%) category. Improved standardization of data collection and documentation is required to better understand harbor porpoise and ecosystem health.
1989-05-01
model otherwise. 7. One or more partial differential equations can be presented to describe the minutia of chemical behavior in the various locales of...enjoys a voluminous literature heritage beyond the point of realistic applications to the natural environment in many cases. Hill, Myers, and Brannon...represented by the point A in Figure 2. This point may be representative of the recently deposited and exposed surface of dredged sediment in the delta
2014-10-01
Arming and Refueling Points for Fighter Aircraft Feature Fifth-Generation Doolittle Raid If we should have to fight, we should be prepared to do so from...the neck up instead of from the neck down. —Gen Jimmy Doolittle The famous Doolittle Raid during World War II offers a superb exam- ple of how an...innovative concept can lead to strategic effects. On 18 April 1942, just four months after the Japanese attack on Pearl Harbor, Lt Col Jimmy Doolittle
1981-06-01
sessile marine inverte- brates in Monterey harbor. Veliger 17 (supplement): 1-35. 1977. The nature of primary organic films in the marine environment and...I A10A4h 605 NAVAL POSTGRADUATE SCHOOL MONTEREY CA F/S 11/3 SCANING ELECTRON MICROSCOPE OBSERVATIONS OF MARINE MICROORANI-E-C(U) UNLSSIFIED N*2...Scanning Electron Microscope Observations Master’s thesis; of Marine Microorganisms on Surfaces June 1981 Coated with Ant ifouling Paints 6.PERFORMING
Coating Performance in Duluth Superior Harbor. Part 1
2012-09-01
chemistry electron microscopy, and electrochemical techniques to in adsorption, bwfouling, hiodegrad ttoa, Mad corrosion in marine environments. She is a... Study off’nrrnmon Kxpowirc Testing h’tiUir Ä/jjjj Ijmm *7£ Compam Showcase CATHOOIC P 34 Onlhodte Pmieeiion of Sieel Pipe Pile* in an Open...of n Steel Drinking Water Pipe in an IIKIUOI l.u\\ ii-oiiinini /Juglins ll’iiiqi, .W lJu. Hnxin l’itng, ^kiuri IIV, amiHuijxiut dir» fcC
1976-09-01
the New York Harbor area and especially the Jamaica Bay complex was used to determine the effects of 13 different hurricane surge barrier plans on...vary directly with the total cross-sectional area of the naviga- tion opening and tidal openings. d. barrier plans B, C-l, C-2, and C-3 would have... plan C-1 with a conservative dye source seaward of the barrier indicated that average dye concentrations will be increased slightly in most areas in
1992-05-01
productive. Thus, the area supports a wide variety of marine and terrestrial life. This mild climate and richness of resources has facilitated human ...and they have the ability to coexist with many human endeavors in the marine environment. Although the sand trap will have to be dredged annually... human activity. I 5.4 Fish & Invertebrates East Jetty Sealing: The underwater spaces in the east jetty that are filled with fluidized sand are not
Federal Register 2010, 2011, 2012, 2013, 2014
2012-09-28
... DEPARTMENT OF HOMELAND SECURITY Coast Guard 33 CFR Part 165 [Docket No. USCG-2012-0767] RIN 1625-AA00 Safety Zone, Changes to Original Rule; Boston Harbor's Rock Removal Project, Boston Inner Harbor... original provisions of that temporary final rule, but adds two additional safety zones necessary for the...
Federal Register 2010, 2011, 2012, 2013, 2014
2013-06-27
...-AA08 Special Local Regulations; Red Bull Flugtag National Harbor Event, Potomac River; National Harbor... waters of the Potomac River on September 21, 2013. These special local regulations are necessary to... temporarily restrict vessel traffic in a portion of the Potomac River during the event. DATES: This rule is...
Federal Register 2010, 2011, 2012, 2013, 2014
2013-03-26
...-AA08 Special Local Regulations; Red Bull Flugtag National Harbor Event, Potomac River; National Harbor... event,'' to be held on the waters of the Potomac River on September 21, 2013. These special local... representative. This action is intended to temporarily restrict vessel traffic in a portion of the Potomac River...
Federal Register 2010, 2011, 2012, 2013, 2014
2012-07-19
...--AA08 Special Local Regulations for Marine Events; Potomac River, National Harbor Access Channel, MD... Harbor'' triathlon, a marine event to be held on the waters of the Potomac River in Prince George's...; Potomac River, National Harbor Access Channel, MD'' in the Federal Register (77 FR 20750). The rulemaking...
77 FR 19573 - Safety Zone; Wedding Fireworks Display, Boston Inner Harbor, Boston, MA
Federal Register 2010, 2011, 2012, 2013, 2014
2012-04-02
...-AA00 Safety Zone; Wedding Fireworks Display, Boston Inner Harbor, Boston, MA AGENCY: Coast Guard, DHS... zone on the navigable waters of the Boston Inner Harbor in the vicinity of Anthony's Pier 4, Boston, MA... Boston Inner Harbor in the vicinity of Anthony's Pier 4, Boston, MA. The Captain of the Port (COTP...
77 FR 45239 - Amendment of Class E Airspace; Bar Harbor, ME
Federal Register 2010, 2011, 2012, 2013, 2014
2012-07-31
...-1366; Airspace Docket No. 11-ANE-13] Amendment of Class E Airspace; Bar Harbor, ME AGENCY: Federal... area at Bar Harbor, ME, as the Surry Non-Directional Radio Beacon (NDB) has been decommissioned and new... airspace at Bar Harbor, ME (77 FR 27666) Docket No. FAA-2011-1366. Interested parties were invited to...
Federal Register 2010, 2011, 2012, 2013, 2014
2012-07-10
...-FF02ENEH00] Draft Safe Harbor Agreement and Application for an Enhancement of Survival Permit for the Tres... permit application and the associated draft Safe Harbor Agreement (SHA). DATES: Comment Period: To ensure... . SUPPLEMENTARY INFORMATION: Under a Safe Harbor Agreement, participating property owners voluntarily undertake...
Federal Register 2010, 2011, 2012, 2013, 2014
2010-05-11
... DEPARTMENT OF COMMERCE Foreign-Trade Zones Board [Docket 32-2010] Foreign-Trade Zone 152 - Burns... six sites in the Burns Harbor/Gary, Indiana area: Site 1: (533,288 sq. ft.) located at 201 Mississippi... of Indiana/Burns International Harbor, Burns Harbor (Porter County); Site 3: (330 acres) within the...
77 FR 43513 - Olympia Harbor Days Tug Boat Races, Budd Inlet, WA
Federal Register 2010, 2011, 2012, 2013, 2014
2012-07-25
... Harbor Days Tug Boat Races, Budd Inlet, WA AGENCY: Coast Guard, DHS. ACTION: Notice of enforcement of regulation. SUMMARY: The Coast Guard will enforce the Special Local Regulation, Olympia Harbor Days Tug Boat... Special Local Regulation for Olympia Harbor Days Tug Boat Races, Budd Inlet, WA in 33 CFR 100.1309 on...
Teaching about Pearl Harbor. Curriculum Enhancement Series #1.
ERIC Educational Resources Information Center
Shields, Anna Marshall
These materials consist of sample lesson plans for teaching about the Japanese attack on Pearl Harbor on December 7, 1941, in both U.S. and world history classes. The lesson plans challenge students to examine how current attitudes toward the Japanese may be rooted in World War II and Pearl Harbor. Selected bibliographies on Pearl Harbor, World…
Defense.gov Special Report: 72nd Anniversary of Pearl Harbor
Department of Defense Submit Search 72nd Anniversary of the Attack on Pearl Harbor - World War II News Harbor survivors and World War II veterans gathered at the Pacific National Monument's Pearl Harbor course of world history." Story USS Mesa Verda Crew Conducts Remembrance Ceremony As Americans and
Defense.gov Special Report: Pearl Harbor Anniversary
Department of Defense Submit Search 71th Anniversary of the Attack on Pearl Harbor - World War II News Joint Chiefs of Staff, saluted veterans at the National World War II Memorial in Washington, D.C Attack Video Return To Pearl Harbor Return To Pearl Harbor World War II Timeline The attack on Pearl
Where and What Is Pristine Marine Aerosol?
NASA Astrophysics Data System (ADS)
Russell, L. M.; Frossard, A. A.; Long, M. S.; Burrows, S. M.; Elliott, S.; Bates, T. S.; Quinn, P.
2014-12-01
The sources and composition of atmospheric marine aerosol particles have been measured by functional group composition (from Fourier transform infrared spectroscopy) to identify the organic composition of the pristine primary marine (ocean-derived) particles as 65% hydroxyl, 21% alkane, 6% amine, and 7% carboxylic acid functional groups [Frossard et al., 2014a,b]. Pristine but non-primary components from photochemical reactions (likely from biogenic marine vapor emissions) add carboxylic acid groups. Non-pristine contributions include shipping effluent in seawater and ship emissions, which add additional alkane groups (up to 70%), and coastal or continental emissions mix in alkane and carboxylic acid groups. The pristine primary marine (ocean-derived) organic aerosol composition is nearly identical to model generated primary marine aerosol particles from bubbled seawater, indicating that its overall functional group composition is the direct consequence of the organic constituents of the seawater source. While the seawater organic functional group composition was nearly invariant across all three ocean regions studied and the ratio of organic carbon to sodium (OC/Na+) in the generated primary marine aerosol particles remained nearly constant over a broad range of chlorophyll-a concentrations, the generated primary marine aerosol particle alkane group fraction increased with chlorophyll-a concentrations. In addition, the generated primary marine aerosol particles have a hydroxyl group absorption peak location characteristic of monosaccharides and disaccharides, where the seawater hydroxyl group peak location is closer to that of polysaccharides. References Cited Frossard, Amanda A., Lynn M. Russell, Paola Massoli, Timothy S. Bates, and Patricia K. Quinn, "Side-by-Side Comparison of Four Techniques Explains the Apparent Differences in the Organic Composition of Generated and Ambient Marine Aerosol Particles," Aerosol Science and Technology - Aerosol Research Letter, 48:v-x, doi10.1080/02786826.2013.879979, 2014a. Frossard, A.A., L.M. Russell, M.S. Long, S.M. Burrows, S.M. Elliot, T.S. Bates, and P.K. Quinn, "Sources and Composition of Submicron Organic Mass in Marine Aerosol Particles," Journal of Geophysical Research - Atmospheres, submitted 2014b.