Letter to Editor Regarding the OCEAN Study [Letter]

The article is dedicated to review of structural and evolutionary peculiarities of the southern part of central sector of the Indian ocean. Study is based on analyses of global digital models, distribution of fractures, global and regional lithosphere evolution models and published geological and geophysical data. As a result of study, tectonic regionalization of oceanic crust of the area is presented and main evolution stages of the region are distinguished.

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Relationship between polymetallic nodule genesis and sediment distribution in the KODOS (Korea Deep Ocean Study) Area, Northeastern Pacific

Ocean Science Journal ◽

10.1007/s12601-012-0020-8 ◽

2012 ◽

Vol 47 (3) ◽

pp. 197-207 ◽

Cited By ~ 9

Author(s):

Jonguk Kim ◽

Kiseong Hyeong ◽

Hyun-Bok Lee ◽

Young-Tak Ko

Keyword(s):

Deep Ocean ◽

Sediment Distribution ◽

Polymetallic Nodule ◽

Northeastern Pacific ◽

Ocean Study

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On the chemical dynamics of extracellular polysaccharides in the high Arctic surface microlayer

Ocean Science ◽

10.5194/os-8-401-2012 ◽

2012 ◽

Vol 8 (4) ◽

pp. 401-418 ◽

Cited By ~ 42

Author(s):

Q. Gao ◽

C. Leck ◽

C. Rauschenberg ◽

P. A. Matrai

Keyword(s):

Molecular Weight ◽

Organic Matter ◽

Compositional Analysis ◽

Physicochemical Characteristics ◽

High Arctic ◽

The Arctic ◽

Extracellular Polysaccharides ◽

Surface Microlayer ◽

Biological Origin ◽

Ocean Study

Abstract. The surface microlayer (SML) represents a unique system of which the physicochemical characteristics may differ from those of the underlying subsurface seawater (SSW). Within the Arctic pack ice area, the SML has been characterized as enriched in small colloids of biological origin, resulting from extracellular polymeric secretions (EPS). During the Arctic Summer Cloud Ocean Study (ASCOS) in August 2008, particulate organic matter (POM, with size range > 0.22 μm) and dissolved organic matter (DOM, < 0.22 μm, obtained after filtration) samples were collected and chemically characterized from the SML and the corresponding SSW at an open lead centered at 87.5° N and 5° E. Total organic carbon was persistently enriched in the SML with a mean enrichment factor (EF) of 1.45 ± 0.41, whereas sporadic depletions of dissolved carbohydrates and amino acids were observed. Monosaccharide compositional analysis reveals that EPS in the Arctic lead was formed mainly of distinctive heteropolysaccharides, enriched in xylose, fucose and glucose. The mean concentrations of total hydrolysable neutral sugars in SSW were 94.9 ± 37.5 nM in high molecular weight (HMW) DOM (> 5 kDa) and 64.4 ± 14.5 nM in POM. The enrichment of polysaccharides in the SML appeared to be a common feature, with EFs ranging from 1.7 to 7.0 for particulate polysaccharides and 3.5 to 12.1 for polysaccharides in the HMW DOM fraction. A calculated monosaccharide yield suggests that polymers in the HMW DOM fraction were scavenged, without substantial degradation, into the SML. Bubble scavenging experiments showed that newly aggregated particles could be formed abiotically by coagulation of low molecular weight nanometer-sized gels. Aerosol particles, artificially generated by bubbling experiments, were enriched in polysaccharides by factors of 22–70, relative to the source seawater. We propose that bubble scavenging of surface-active polysaccharides could be one of the possible mechanisms for the enrichment of polysaccharides in the high Arctic open lead SML.

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Long Term Upper Ocean Study (Lotus) at 34 degrees N, 70 degrees W : meteorological sensors, data, and heat fluxes for May-October 1982 (Lotus-3 and Lotus-4)

10.1575/1912/8502 ◽

1983 ◽

Cited By ~ 1

Author(s):

Clara Deser ◽

Robert A. Weller ◽

Melbourne G. Briscoe

Keyword(s):

Heat Fluxes ◽

Upper Ocean ◽

Ocean Study

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ORCA study: real-world versus reading centre assessment of disease activity of neovascular age-related macular degeneration (nAMD)

British Journal of Ophthalmology ◽

10.1136/bjophthalmol-2019-315717 ◽

2020 ◽

pp. bjophthalmol-2019-315717 ◽

Cited By ~ 2

Author(s):

Sandra Liakopoulos ◽

Georg Spital ◽

Christian K Brinkmann ◽

Tina Schick ◽

Focke Ziemssen ◽

...

Keyword(s):

Macular Degeneration ◽

Image Interpretation ◽

Subretinal Fluid ◽

Treatment Decisions ◽

Age Related Macular Degeneration ◽

Correct Identification ◽

Age Related ◽

Ocean Study ◽

The Impact ◽

Sd Oct

Background/aimsThe prospective, non-interventional ORCA module of the OCEAN study (Observation of Treatment Patterns with Lucentis in Approved Indications) evaluated the qualiy of spectral domain-optical coherence tomography (SD-OCT) image interpretation and treatment decisions by clinicians in Germany and the impact on visual outcomes over 24 months in patients with neovascular age-related macular degeneration (nAMD).Methods2286 SD-OCT scans of 205 eyes were independently evaluated by clinicians and reading centres (RCs) regarding signs of choroidal neovascularisation (CNV) activity, including presence of intraretinal fluid, subretinal fluid, and/or increase in pigment epithelial detachments. Agreement between clinicians and RCs was calculated. Treatment decisions by clinicians and the impact on treatment outcomes were evaluated.ResultsCNV activity was detected by RCs on 1578 scans (69.0%) and by clinicians on 1392 scans (60.9%), with agreement in 74.9% of cases. Of the 1578 scans with RC detected CNV activity, anti-vascular endothelial growth factor injections were performed by clinicians in only 35.5% (560/1578). In 19.7% of cases (311/1578), lack of treatment was justified by patients request, termination criteria or chronic cystoid spaces without other signs for CNV activity. In 44.8% of cases (707/1578) with RC detected CNV activity, clinicians claimed no treatment was necessary despite having correctly detected CNV activity in about 2/3 of these cases. In 34% of cases with presumed undertreatment, visual acuity declined in the following visit.ConclusionAlthough broad agreement on CNV activity parameters was observed between clinicians and RCs, correct identification of CNV activity did not always lead to the initiation of (re-)treatment. To preserve vision over time, correct interpretation of SD-OCT scans and careful retreatment decisions are required.Trial registration numberNCT02194803.

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On the potential contribution of open lead particle emissions to the central Arctic aerosol concentration

Atmospheric Chemistry and Physics ◽

10.5194/acp-11-3093-2011 ◽

2011 ◽

Vol 11 (7) ◽

pp. 3093-3105 ◽

Cited By ~ 34

Author(s):

A. Held ◽

I. M. Brooks ◽

C. Leck ◽

M. Tjernström

Keyword(s):

Particle Deposition ◽

Particle Number ◽

Mixing Layer ◽

Open Water ◽

Potential Contribution ◽

Central Arctic Ocean ◽

Lead Particle ◽

Ocean Study ◽

Number Variation ◽

Atmospheric Variations

Abstract. We present direct eddy covariance measurements of aerosol number fluxes, dominated by sub-50 nm particles, at the edge of an ice floe drifting in the central Arctic Ocean. The measurements were made during the ice-breaker borne ASCOS (Arctic Summer Cloud Ocean Study) expedition in August 2008 between 2°–10° W longitude and 87°–87.5° N latitude. The median aerosol transfer velocities over different surface types (open water leads, ice ridges, snow and ice surfaces) ranged from 0.27 to 0.68 mm s−1 during deposition-dominated episodes. Emission periods were observed more frequently over the open lead, while the snow behaved primarily as a deposition surface. Directly measured aerosol fluxes were compared with particle deposition parameterizations in order to estimate the emission flux from the observed net aerosol flux. Finally, the contribution of the open lead particle source to atmospheric variations in particle number concentration was evaluated and compared with the observed temporal evolution of particle number. The direct emission of aerosol particles from the open lead can explain only 5–10% of the observed particle number variation in the mixing layer close to the surface.

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