The Southern Brazilian Continental Shelf (SBCS) is one of the more productive areas for fisheries in Brazilian waters. The water masses and the dynamical processes of the region present a very ...seasonal behavior that imprint strong effects in the ecosystem and the weather of the area and its vicinity. This paper makes use of the Regional Ocean Modeling System (ROMS) for studying the water mass distribution and circulation variability in the SBCS during the year of 2012. Model outputs were compared to in situ, historical observations and to satellite data. The model was able to reproduce the main thermohaline characteristics of the waters dominating the SBCS and the adjacent region. The mixing between the Subantarctic Shelf Water and the Subtropical Shelf Water, known as the Subtropical Shelf Front (STSF), presented a clear seasonal change in volume. As a consequence of the mixing and of the seasonal oscillation of the STSF position, the stability of the water column inside the SBCS also changes seasonally. Current velocities and associated transports estimated for the Brazil Current (BC) and for the Brazilian Coastal Current (BCC) agree with previous measurements and estimates, stressing the fact that the opposite flow of the BCC occurring during winter in the study region is about 2 orders of magnitude smaller than that of the BC. Seasonal maps of simulated Mean Kinetic Energy and Eddy Kinetic Energy demonstrate the known behavior of the BC and stressed the importance of the mean coastal flow off Argentina throughout the year.
Key Points
The annual variability of water masses and circulation at the SBCS are studied using regional modeling
The Subtropical Shelf Front (STSF) presented a clear change in volume between summer and winter
Water masses, current velocities and transports, MKE and EKE estimates, and variability are consistent with previous measurements.
For the first time, in situ turbulence measurements collected in the vicinity of the Brazil‐Malvinas Confluence are used to determine the influence of the ocean waves and atmospheric stability on the ...Marine Atmospheric Surface Layer. From the analysis of 187 high‐frequency sampled segments of temperature and wind velocity, carefully selected from three ship campaigns of the Air‐Sea Interaction at Brazil‐Malvinas Confluence project, we found a particular behavior of the drag coefficient, with a negative trend for a calm wind speed up to 10 m/s when the significant wave height was lower than 2.5 m, and a continuous decrease of the drag coefficient with increasing wind speed for significant wave height higher than 2.5 m. The results suggest that waves act as roughness elements during high wave conditions, inducing a zero‐plane displacement in the order of 0.1 to 1 m as an indication for a wave‐induced roughness layer. In addition, the analysis of the turbulent kinetic energy (TKE) budget indicates the occurrence of upward TKE transport mainly during stable conditions, while the general patterns of transport and dissipation of TKE are similar to observations taken over land surfaces.
Key Points
Brazil‐Malvinas Confluence region
Marine atmospheric surface layer
Wave‐induced roughness layer
The aim of this study was to investigate, using ultrasound (US), knee involvement in patients with Behçet's disease (BD).
Knee US was performed in 30 unselected Italian BD patients. Signs of ...arthritis (joint effusion, synovial proliferation) and presence of bone erosions and Baker's cysts were recorded. Power Doppler evaluation was performed. A semi-quantitative score was used for each structure examined, whereby 0 was to indicate the absence of any change and score from 1 to 3 the presence of mild to severe changes. A sum of the single scores was obtained. Disease activity was evaluated to identify the correlation with the US modifications.
Twenty (66.6%) patients had symptomatic articular involvement and US showed knee involvement in 18 of them (60%). Synovial proliferation was detected in 14 (46%, positive power Doppler in 4), joint effusion in 14 (46%), bone surface erosions in 3 (10%). Four patients, asymptomatic for joint involvement, showed US alterations. Eleven patients showed a total score between 1 and 3, while the other 7 had a score between 4 and 6. Subjects with a higher US score presented an increased prevalence of acneiform skin lesions with respect to the group with US score 1-3. Statistical analysis showed a positive correlation between disease activity and US score in group 2 (p=0.04).
This study confirms that peripheral joint involvement represents an important clinical aspect in italian BD patients and US evaluation is useful for the detection of this aspect.
To report the changing patterns of ocular manifestations in human immunodeficiency virus (HIV) seropositive patients treated with highly active antiretroviral therapy (HAART).
The clinical charts of ...HIV seropositive patients, 735 examined from 1997 to 2003 and treated with HAART for at least 2 months (Group 1), and 838 untreated examined from 1988 to 1995 (Group 2), were reviewed to assess the frequency of ocular manifestations.
HIV-related retinal microangiopathy and opportunistic retinal infections (cytomegalovirus retinitis and toxoplasmic retinochoroiditis) were significantly higher in Group 2 than 1 (p<0.0001), while in patients treated with HAART a statistically significant increase in the frequency of chalazion (p<0.0001), diabetic and hypertensive retinopathy (p<0.0001), lipid arc of the cornea (p<0.0001), cataract and glaucoma (p<0.0001), and uveitis (p=0.026) was observed.
HAART therapy has induced a dramatic decrease in the incidence of HIV-related microangiopathy and opportunistic retinal infection and the occurrence of new lesions related both to the metabolic alterations induced by HAART and to immune reconstitution, such as uveitis.
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