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1.
Sci Total Environ ; 891: 164666, 2023 Sep 15.
Article in English | MEDLINE | ID: mdl-37286011

ABSTRACT

The compositions of organic carbon could be important in determining biological carbon pump efficiency. However, little information on them in relation to each algal assemblage is currently available in the Ross Sea. Here, we investigated the seasonal variations in organic carbon composition and the relative abundance of each organic carbon, including particulate organic carbon (POC), dissolved organic carbon (DOC), and transparent exopolymer particles (TEPs), characterized by different algal groups in the Ross Sea. The average POC and DOC contributions to the total organic carbon (TOC = POC + DOC) were 13.8 ± 3.7 % and 86.2 ± 3.7 % in mid-January 2019 and 20.9 ± 4.1 % and 79.1 ± 4.1 % in February-March 2018, respectively. The carbon content of TEP (TEP-C) contributed 19.6 ± 11.7 % and 4.6 ± 7.0 % of POC and TOC in mid-January and 36.2 ± 14.8 % and 9.0 ± 6.7 % in February-March, respectively. We found that the organic carbon compositions were affected by seasonal variations in the phytoplankton bloom phase, physical characteristics, and phytoplankton community structure. DOC concentrations and contributions to the TOC increased as phytoplankton cells became senescent in mid-January and decreased in February-March when phytoplankton were relatively active. From February-March, the deepened mixed layer depth encouraged TEP formation, subsequently increasing the TEP contributions. Regardless of the sampling season, all organic carbon concentrations per unit Chl-a were significantly higher in P. antarctica-abundant groups. The DOC contributions to the TOC were correspondingly higher at the P. antarctica-abundant stations in mid-January, which indicates that P. antarctica could be also important in the DOC contributions in the Ross Sea. The rapid alteration in environmental characteristics and phytoplankton community structures in the Ross Sea due to climate change could affect the organic carbon pool at the euphotic layer which consequently could determine the efficiency of the biological pump.


Subject(s)
Carbon , Environmental Monitoring , Phytoplankton , Dissolved Organic Matter , Spatio-Temporal Analysis
2.
Acta Ophthalmol ; 100(2): e470-e477, 2022 Mar.
Article in English | MEDLINE | ID: mdl-34318607

ABSTRACT

PURPOSE: To evaluate ocular hypotensive efficacy and the safety of sovesudil (formally known as PHP-201), a novel Rho-associated protein kinase (ROCK) inhibitor, in patients with normal-tension glaucoma (NTG). DESIGN: Multicentre, prospective, double-masked, randomized, placebo-controlled, parallel clinical study. METHODS: Patients with NTG (unmedicated baseline IOP ≤ 21 mmHg) were randomized in 3 groups and treated with sovesudil in concentrations of 0.25% and 0.5%, or with a placebo three times daily (TID) for 4 weeks. The primary end-point was the mean diurnal IOP change from the baseline at week 4. Safety was recorded over a 4-week treatment period and the following 2-week observation period. RESULTS: A total of 119 patients were included in the primary efficacy analysis. The mean diurnal IOP change from the baseline at week 4 was -1.56 mmHg for the high-dose group, -1.10 mmHg for the low-dose group and -0.65 mmHg for the placebo group. The difference between the high-dose and the placebo groups was -0.91 mmHg (95% confidence intervals: -1.73, -0.09). 0.5% sovesudil TID met the criteria for superiority to the placebo. The most frequent ocular adverse event among sovesudil-treated patients was conjunctival hyperaemia (24.4% for the high-dose and 17.5% for the low-dose group) and predominately classified as mild. CONCLUSIONS: Sovesudil 0.25% and 0.5% TID showed statistically significant IOP-lowering effects and 0.5% concentration's IOP-lowering effects met the superiority criteria in comparison with the placebo at week 4. Sovesudil was well tolerated with mild adverse events including relatively low incidence of conjunctival hyperaemia in patients with NTG.


Subject(s)
Intraocular Pressure , Low Tension Glaucoma , rho-Associated Kinases , Aged , Female , Humans , Male , Middle Aged , Dose-Response Relationship, Drug , Double-Blind Method , Intraocular Pressure/drug effects , Low Tension Glaucoma/drug therapy , Ocular Hypertension , rho-Associated Kinases/antagonists & inhibitors , rho-Associated Kinases/therapeutic use
3.
J Opt Soc Am A Opt Image Sci Vis ; 36(3): 428-435, 2019 Mar 01.
Article in English | MEDLINE | ID: mdl-30874179

ABSTRACT

A hand-held camera that is capable of acquiring full parallax multiview images is introduced. Since the camera is based on spatial sharing of the aperture stop of a digital camera, it is easy to manufacture. The aperture stop is spatially shared by a 2D high-speed liquid crystal (LC) shutter array that is fixed on the front surface of the camera objective. The shutter array consists of 8×8 LC shutters to acquire 8×8 multiview images. The equivalent optical configuration of the camera is not different from that of a parallel-type multiview camera array. Each of the multiview images has an equal disparity from its neighbors and has the full detector resolution of the camera. The disparity is small enough to be used in light field imaging. The depth resolution and the resolvable number of depth layers calculated from the configuration are not different from those obtained experimentally.

4.
Appl Opt ; 43(26): 4985-92, 2004 Sep 10.
Article in English | MEDLINE | ID: mdl-15468698

ABSTRACT

The viewing zone of autostereoscopic imaging systems that use lenticular, parallax-barrier, and microlens-array plates as the viewing-zone-forming optics is analyzed in order to verify the image-quality differences between different locations of the zone. The viewing zone consists of many subzones. The images seen at most of these subzones are composed of at least one image strip selected from the total number of different view images displayed. These different view images are not mixed but patched to form a complete image. This image patching deteriorates the quality of the image seen at different subzones. We attempt to quantify the quality of the image seen at these viewing subzones by taking the inverse of the number of different view images patched together at different subzones. Although the combined viewing zone can be extended to almost all of the front space of the imaging system, in reality it is limited mainly by the image quality.


Subject(s)
Algorithms , Image Enhancement/methods , Image Interpretation, Computer-Assisted/methods , Imaging, Three-Dimensional/methods , User-Computer Interface , Vision, Binocular
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