Microfluidics : the fur-free way towards personalised medicine in cancer therapy

Microfluidic technology has great potential for complementing and, in some instances, replacing the use of animal models in the testing of medicines and in developing personalised treatments for cancer patients. The maintenance of tissue in an in vivo-like state provides a platform upon which normal and diseased tissue biology can be investigated in a novel way. This review describes the use of microfluidic technology for the maintenance of tissue samples ex vivo and the current state of play for the use of this technology in the replacement of animal models, with a focus on cancer

R/V Oceanus Voyage 449-6 Red Sea Atlantis II Deep Complex Area 19 October–1 November 2008

The purpose of this report is to summarize the research activities conducted during R/V Oceanus Voyage 449-6 (also referred to as KAUST Leg 2) in the Red Sea. The cruise began on 19 October 2008 at 1700 Local Time (LT), when the R/V Oceanus departed Jeddah Commercial Port. On the cruise were 15 scientists from five countries, including Saudi Arabia, United States, Egypt, Hong Kong and Sudan. The cruise ended on 1 November 2008 when the Oceanus returned to the Jeddah Commercial Port.Funding for this report was provided by the King Abdullah University of Science and Technology (KAUST) under a cooperative research agreement with Woods Hole Oceanographic Institution

The response of the Red Sea to a strong wind jet near the Tokar Gap in summer

Author Posting. © American Geophysical Union, 2013. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research 118 (2013): 421–434, doi:10.1029/2012JC008444.Remote sensing and in situ observations are used to investigate the ocean response to the Tokar Wind Jet in the Red Sea. The wind jet blows down the atmospheric pressure gradient through the Tokar Gap on the Sudanese coast, at about 19°N, during the summer monsoon season. It disturbs the prevailing along-sea (southeastward) winds with strong cross-sea (northeastward) winds that can last from days to weeks and reach amplitudes of 20–25 m/s. By comparing scatterometer winds with along-track and gridded sea level anomaly observations, it is observed that an intense dipolar eddy spins up in response to the wind jet. The eddy pair has a horizontal scale of 140 km. Maximum ocean surface velocities can reach 1 m/s and eddy currents extend more than 100 m into the water column. The eddy currents appear to cover the width of the sea, providing a pathway for rapid transport of marine organisms and other drifting material from one coast to the other. Interannual variability in the strength of the dipole is closely matched with variability in the strength of the wind jet. The dipole is observed to be quasi-stationary, although there is some evidence for slow eastward propagation in an idealized numerical model. Simulation of the dipole in an idealized high-resolution numerical model suggests that this is the result of self-advection.This work was supported by award USA 00002, KSA 00011 and KSA 00011/02 made by King Abdullah University of Science and Technology (KAUST).2013-07-3

Iceland-Scotland Overflow Water transport variability through the Charlie-Gibbs Fracture Zone and the impact of the North Atlantic Current

Author Posting. © American Geophysical Union, 2017. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research: Oceans 122 (2017): 6989–7012, doi:10.1002/2017JC012698.The Charlie-Gibbs Fracture Zone (CGFZ), a deep and wide gap in the Mid-Atlantic Ridge near 52°N, is a gateway between the eastern and western subpolar regions for the Atlantic Meridional Overturning Circulation (AMOC). In 2010–2012, an eight-mooring array of current meters and temperature/salinity sensors was installed across the CGFZ between 500 m and the sea floor to measure the mean transport of westward-flowing Iceland-Scotland Overflow Water (ISOW) and investigate the impact of the eastward-flowing North Atlantic Current (NAC) on ISOW transport variability. The 22 month record mean ISOW transport through the CGFZ, −1.7 ± 0.5 Sv (95% confidence interval), is 30% lower than the previously published estimate based on 13 months of current-only measurements, −2.4 ± 1.2 Sv. The latter mean estimate may have been biased high due to the lack of continuous salinity measurements, although the two estimates are not statistically different due to strong mesoscale variability in both data sets. Empirical Orthogonal Function analysis and maps of satellite-derived absolute dynamic topography show that weak westward ISOW transport events and eastward reversals are caused by northward meanders of the NAC, with its deep-reaching eastward velocities. These results add to growing evidence that a significant fraction of ISOW exits the Iceland Basin by routes other than the CGFZ.U.S. National Science Foundation Grant Number: OCE-0926656; Woods Hole Oceanographic Institution2018-03-0

Mesoscale eddies in the Gulf of Aden and their impact on the spreading of Red Sea Outflow Water

Author Posting. © The Author(s), 2010. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Progress In Oceanography 96 (2012): 14-39, doi:10.1016/j.pocean.2011.09.003.The Gulf of Aden (GOA) in the northwestern Indian Ocean is the receiving basin for Red Sea Outflow Water (RSOW), one of the World’s few high-salinity dense overflows, but relatively little is known about spreading pathways and transformation of RSOW through the gulf. Here we combine historical data, satellite altimetry, new synoptic hydrographic surveys and the first in situ direct observations of subsurface currents in the GOA to identify the most important processes in the spreading of RSOW. The new in situ data sets were collected in 2001-2003 as part of the Red Sea Outflow Experiment (REDSOX) and consist of two CTD/LADCP Surveys and 49 one-year trajectories from acoustically tracked floats released at the depth of RSOW. The results indicate that the prominent positive and negative sea level anomalies frequently observed in the GOA with satellite altimetry are associated with anticyclonic and cyclonic eddies that often reach to at least 1000 m depth, i.e., through the depth range of equilibrated RSOW. The eddies dominate RSOW spreading pathways and help to rapidly mix the outflow water with the background. Eddies in the central and eastern gulf are basin-scale (~250-km diameter) and have maximum azimuthal speeds of about 30 cm/s at the RSOW level. In the western gulf, smaller eddies not detectable with satellite altimetry appear to form as the larger westward-propagating eddies impale themselves on the high ridges flanking the Tadjura Rift. Both the hydrographic and Lagrangian observations show that eddies originating outside the gulf often transport a core of much cooler, fresher water from the Arabian Sea all the way to the western end of the GOA, where the highest-salinity outflow water is found. This generates large vertical and horizontal gradients of temperature and salinity, setting up favorable conditions for salt fingering and diffusive convection. Both of these mixing processes were observed to be active in the gulf. Two new annually appearing anticyclonic eddies are added to the previously identified Gulf of Aden Eddy (GAE; Prasad and Ikeda, 2001) and Somali Current Ring (SCR; Fratantoni et al., 2006). These are the Summer Eddy (SE) and the Lee Eddy (LE), both of which form at the beginning of the summer monsoon when strong southwest winds blowing through Socotra Passage effectively split the GAE into two smaller eddies. The SE strengthens as it propagates westward deeper in the GOA, while the Lee Eddy remains stationary in the lee of Socotra Island. Both eddies are strengthened or sustained by Ekman convergence associated with negative wind stress curl patches caused by wind jets through or around high orography. The annual cycle in the appearance, propagation and demise of these new eddies and those described in earlier work is documented to provide a comprehensive view of the most energetic circulation features in the GOA. The observations contain little evidence of features that have been shown previously to be important in the spreading of Mediterranean Outflow Water (MOW) in the North Atlantic, namely a wall-bounded subsurface jet (the Mediterranean Undercurrent ) and submesoscale coherent lenses containing a core of MOW (‘meddies’). This is attributed to the fact that the RSOW enters the open ocean on a western boundary. High background eddy kinetic energy typical of western boundary regimes will tend to shear apart submesoscale eddies and boundary undercurrents. Even if a submesoscale lens of RSOW did form in the GOA, westward self-propagation would transport the eddy and its cargo of outflow water back toward, rather than away from, its source.This work was supported by grants to the Woods Hole Oceanographic Institution by the U.S. National Science Foundation

Boundary current experiment I & II, RAFOS float data report, 1994-1997

This is the final data report of all RAFOS (acoustically tracked) float data collected during the 1994-1997 Boundary Current Experiment (BOUNCE) study of the Deep Western Boundary Current (DWBC) in the North Atlantic Ocean. The overall objective of the program was to obtain the first comprehensive description of the North Atlantic DWBC's variability over a large path segment from Cape Hatteras to the Grand Banks. The experiment was comprised of CTD, tracer, and RAFOS float observations to achieve both Eulerian and Lagrangian descriptions of the DWBC. The three main objectives of the Lagrangian float study were 1) to determine fluid parcel pathways in the DWBC and identify regions of exchange with the interior, 2) to estimate the mean speed and variabilty of fluid parcels at two different levels in the DWBC, and 3) to study the kinematics and potential vorticity dynamics of fluid parcels in the DWBC at the Gulf Stream cross-over point near Cape Hatteras. Thirty floats were deployed: 15 were designed to be isopycnal floats, and 15 were isobaric floats. The isopycnal floats were ballasted for the 0, = 27.73 density surface (approximately 800 decibars (db)) to seed the Upper Labrador Sea Water. The isobaric floats were ballasted for 3000 db to seed the Nordic Seas overflow water.Funding was provided by the National Science Foundation under Grant OCE-93-01448

Seasonal and interannual variability of the West Greenland Current System in the Labrador Sea in 1993–2008

Author Posting. © American Geophysical Union, 2015. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research: Oceans 120 (2015): 1318–1332, doi:10.1002/2014JC010386.The West Greenland Current System (WGCS) transports heat and freshwater into the Labrador Sea, influencing the formation of Labrador Sea Water, a key component of the Atlantic Meridional Overturning Circulation. Notwithstanding its importance, relatively little is known about the structure and transport of this current system and its seasonal and interannual variability. Here we use historical hydrographic data from 1992 to 2008, combined with AVISO satellite altimetry, to diagnose the mean properties as well as seasonal and interannual variability of the boundary current system. We find that while the surface, fresh, cold West Greenland Current is amplified in summer, the subsurface warm, salty Irminger Current has maximum transport in winter, when its waters are also warmer and saltier. Seasonal changes in the total transport are thus mostly due to changes in the baroclinic structure of the current. By contrast, we find a trend toward warmer/saltier waters and a slowdown of the WGCS, within the period studied. The latter is attributed to changes in the barotropic component of the current. Superimposed on this trend, warm and salty anomalies transit through the system in 1997 and 2003 and are associated with a rapid increase in the transport of the boundary current due to changes in the baroclinic component. The boundary current changes precede similar changes in the interior with a 1–2 year lag, indicating that anomalies advected into the region by the boundary current can play an important role in the modulation of convection in the Labrador Sea.T.R. and F.S. were supported by NSF OCE grants 0525929 and 0850416. A.B. was supported by NSF OCE grant 0623192.2015-08-2

Meridional heat transport variability induced by mesoscale processes in the subpolar North Atlantic

© The Author(s), 2018. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Nature Communications 9 (2018): 1124, doi:10.1038/s41467-018-03134-x.The ocean’s role in global climate change largely depends on its heat transport. Therefore, understanding the oceanic meridional heat transport (MHT) variability is a fundamental issue. Prevailing observational and modeling evidence suggests that MHT variability is primarily determined by the large-scale ocean circulation. Here, using new in situ observations in the eastern subpolar North Atlantic Ocean and an eddy-resolving numerical model, we show that energetic mesoscale eddies with horizontal scales of about 10–100 km profoundly modulate MHT variability on time scales from intra-seasonal to interannual. Our results reveal that the velocity changes due to mesoscale processes produce substantial variability for the MHT regionally (within sub-basins) and the subpolar North Atlantic as a whole. The findings have important implications for understanding the mechanisms for poleward heat transport variability in the subpolar North Atlantic Ocean, a key region for heat and carbon sequestration, ice–ocean interaction, and biological productivity.J.Z. was financially supported by the Postdoctoral Scholar Program at WHOI, with funding provided by the Ocean and Climate Change Institute. This work was also supported by the US National Science Foundation (OCE-1258823 and OCE-1634886), as well as by China’s national key research and development projects (2016YFA0601803), the National Natural Science Foundation of China (41521091 and U1606402), the Qingdao National Laboratory for Marine Science and Technology (2015ASKJ01), and the Fundamental Research Funds for the Central Universities (201424001 and 201362048)

Author correction : Meridional heat transport variability induced by mesoscale processes in the subpolar North Atlantic

© The Author(s), 2018. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Nature Communications 9 (2018): 2398, doi:10.1038/s41467-018-04809-1