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This study presents novel observational estimates of turbulent dissipation and mixing in a standing meander between the Southeast Indian Ridge and the Macquarie Ridge in the Southern Ocean. By applying a finescale parameterization on the temperature, salinity, and velocity profiles collected from Electromagnetic Autonomous Profiling Explorer (EM-APEX) floats in the upper 1600 m, we estimated the intensity and spatial distribution of dissipation rate and diapycnal mixing along the float tracks and investigated the sources. The indirect estimates indicate strong spatial and temporal variability of turbulent mixing varying from O(10−6) to O(10−3) m2 s−1 in the upper 1600 m. Elevated turbulent mixing is mostly associated with the Subantarctic Front (SAF) and mesoscale eddies. In the upper 500 m, enhanced mixing is associated with downward-propagating wind-generated near-inertial waves as well as the interaction between cyclonic eddies and upward-propagating internal waves. In the study region, the local topography does not play a role in turbulent mixing in the upper part of the water column, which has similar values in profiles over rough and smooth topography. However, both remotely generated internal tides and lee waves could contribute to the upward-propagating energy. Our results point strongly to the generation of turbulent mixing through the interaction of internal waves and the intense mesoscale eddy field.

We characterize the internal wave field at a standing meander of the Antarctic Circumpolar Current (ACC) where strong winds, bathymetry, and a strong eddy field combine to form a dynamic environment for the generation and dissipation of internal waves. We use Electromagnetic Autonomous Profiling Explorer float data spanning 0−1600 m depth collected from a meander near the Macquarie Ridge, south of Australia. Of the 112 internal waves identified, 69% are associated with upward energy propagation. Most of the upward propagating waves (35%) are found near the Polar Front and are likely generated by mean flow-topography interactions. Generation by wind forcing at the sea surface is likely responsible for more than 40% of the downward propagating waves. Our results highlight advection of the waves and wave-mean flow interactions within the ACC as the dominant processes affecting the wave dynamics. The larger dissipation timescales of the waves compared to advection suggests they are likely to dissipate away from the generation site. We find that about 79% (66%) of the waves in cyclonic eddies (the Subantarctic Front) are influenced by horizontal strain, whereas 92% of the waves in the slower Polar Front are influenced by the relative vorticity of the background flow. There is energy exchange between internal waves and the mean flow, in both directions. The mean energy transfer (1.4±1.0×10−11 m2 s−3) is from the mean flow to the waves in all dynamic regions except in anticyclonic eddies. The strongest energy exchange (5.0±3.7×10−11 m2 s−3) is associated with waves in cyclonic eddies.

This study presents the characteristics and spatiotemporal structure of near-inertial waves and their interaction with Leeuwin Current eddies in the eastern south Indian Ocean as observed by Electromagnetic Autonomous Profiling Explorer (EM-APEX) floats. The floats sampled the upper ocean during July–October 2013 with a frequency of eight profiles per day down to 1200 m. Near-inertial waves (NIWs) are found to be the dominant signal in the frequency spectra. Complex demodulation is used to estimate the amplitude and phase of the NIWs from the velocity profiles. The NIW energy propagated from the base of the mixed layer downward into the ocean interior, following beam characteristics of linear wave theory. We visually identified a total of 15 near-inertial internal wave packets from the wave amplitudes and phases with a mean vertical wavelength of 89 ± 63 m, a mean horizontal wavelength of 69 ± 85 km, a mean horizontal group velocity of 3 ± 2 cm s−1, and a mean vertical group velocity of 9 ± 7 m day−1. A strong near-inertial packet with a kinetic energy of 20–30 J m−3 found propagating below 700 m suggests that the NIWs can contribute to deep ocean mixing. A blue shift of 10%–15% in the energy spectrum of the NIWs is observed in the upper 1200 m as the floats move toward the equator. The impacts of mesoscale eddies on the characteristics and propagation of the observed NIWs are also investigated. The elevated near-inertial shear variance in anticyclonic eddies suggests trapping of NIWs near the surface. Cyclonic eddies, in contrast, were associated with weak near-inertial shear variance in the upper 400 m.

This study investigates the spatio-temporal variability of turbulent mixing in the eastern South Indian Ocean using a collection of data from EM-APEX profiling floats, shipboard CTD and microstructure profilers. The floats collected 1566 profiles of temperature, salinity and horizontal velocity data down to 1200 m over a period of about four months. A fine-scale parameterization is applied to the float and CTD data to estimate turbulent mixing. Elevated mixing is observed in the upper ocean, over bottom topography and in mesoscale eddies. Mixing is enhanced in the anticyclonic eddies due to trapped near-inertial waves within the eddy. We found that cyclonic eddies contribute to turbulent mixing in the depth range of 500 – 1000 m, which is associated with downward propagating internal waves. The mean diapycnal diffusivity over 250 – 500 m depth is O(10−6) m2 s−1 and it increases to O(10−5) m2 s−1 in 500 – 1000 m in cyclonic eddies. The turbulent mixing in this region has implications for watermass transformation and large-scale circulation. Higher diffusivity (O(10−5) m2 s−1) is observed in the Antarctic Intermediate Water (AAIW) layer in cyclonic eddies whereas weak diffusivity is observed in the Subantarctic Mode Water (SAMW) layer (O(10−6) m2 s−1). Counter-intuitively, then, the SAMW watermass properties are strongly affected in cyclonic eddies whereas the AAIW layer is less affected. Comparatively high diffusivity at the location of the South Indian Countercurrent (SICC) jets suggests there are wave-mean flow interactions in addition to the wave-eddy interactions that warrant further investigation.

While numerous studies have explored prevalence and determinants of intimate partner violence (IPV), one area that has yet to be sufficiently explored is whether men and women agree on the acts, behaviours, and attitudes that comprise IPV. Through the use of concept mapping, we examined the similarities and differences in the conceptualization of IPV among a diverse sample of men and women. Although men and women conceptualized physical and sexual violence similarly, men tended to rate non-physical behaviors related to control as less important to the definition of IPV than women. Moreover, even when men and women used similar labeling language for grouping of items, the statements included in each cluster were substantially different for non-physically abusive items. A greater understanding of similarities and differences in the conceptualization of IPV by gender can help inform appropriate gender specific IPV intervention and prevention efforts.

The Bay of Bengal (BOB) is known to possess complex thermodynamics which show distinct seasonal patterns. Surface heat fluxes in the BOB are very much dependant on upper ocean heat exchanges and wind. Sensible heat flux (SHF) is also one among those fluxes that depends on air-sea temperature difference and wind. However, this study further proves that a strong relationship exists between barrier layer thickness (BLT) and SHF variability that has not been focussed on in earlier literatures. This study also investigates the seasonal as well as inter-annual variability of SHF and its relationship with BLT and sea surface temperature (SST) patterns in more detail with statistical analyses. It is found that both SST and BLT are responsible for the evolution of SHF signal in the BOB although their effects are spatially distributed. During the post monsoon period, freshwater induced enhanced BLT is more related to SHF than the summer time when effect of SST is found to be dominant. During Indian Ocean Dipole (IOD) years, the correlation between SHF and BLT in the eastern BOB is more pronounced compared to SHF and SST. The western BOB however is dominated by SST variations for the respective IOD phase which also contribute to SHF signals there. Northernmost BOB shows high standard deviation due to river discharge effects.

Limited knowledge exists about conceptual variations in defining intimate partner violence (IPV) by ethnicity, such as South Asian (SA) immigrant men and women. In a multi-ethnic study, we employed participatory concept mapping with three phases: brainstorming on what constitutes IPV; sorting of the brainstormed items; and interpretation of visual concept maps generated statistically. The parent study generated an overall general multi-ethnic map (GMEM) that included participant interpretations. In the current study, we generated a SA specific initial-map that was interpreted by eleven SA men and women in gender specific groups. Their interpretations are examined for similar and unique aspects across men and women and compared to GMEM. SA men and women shared similar views about sexual abuse and victim retaliation, which also aligned closely with GMEM. Both SA women and men had an expanded view of the concept of controlling behaviors compared to GMEM. SA women, unlike SA men, viewed some aggressive behaviors and acts as cultural with some GMEM congruence. SA women uniquely identified some IPV acts as private-public. We discuss implications for research and service assessments.

BACKGROUND: This study aims to explore the conceptualization of intimate partner violence (IPV) among men and women from diverse subpopulations in Toronto, ON, Canada. Relatively few research efforts have been made to examine differences in conceptualizations of IPV across populations of different race and ethnic backgrounds. METHODS: Using concept mapping methodology, we sampled 67 women and men identified concepts and groups of concepts (domains) that reflected their understandings of the behaviours and attitudes that comprised IPV. We also determined the relative importance of each concept and domain as a contributor to IPV. RESULTS: 'External and Cultural Influences', 'Victim Response to Abuse' and 'Social and Emotional Manipulation' were a few domains that participants rated as moderately or highly important contributors to IPV. These conceptual domains are often left out of commonly used IPV measures. CONCLUSIONS: Our findings have important implications for the conceptualization of IPV and for future IPV measurement and measurement tool development. Language: en

Africa's HIV-1 epidemic has, appropriately, received global attention. However, India stands to experience the greatest increase in absolute number of HIV-1 cases in the coming decades. As of 2004, at least 5 million people in India have been infected.[1][1] Preventive interventions to decrease