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The North Atlantic Current And Subarctic Intermediate Water, Michel Arhan Jan 1990

The North Atlantic Current And Subarctic Intermediate Water, Michel Arhan

Journal of Marine Research

The region where the North Atlantic Current crosses the ocean around 50N is studied from a watermass point of view and using the ventilated thermocline model of Luyten et al. (1983). Both approaches focus on the part played by the Subarctic Intermediate Water which, owing to its pronounced thermohaline anomalies stands out as a clue to the complex oceanic circulation in this area. Vertical mixing of this watermass with the overlying North Atlantic Central Water creates a fresher variety of central water found between the two major branches of the North Atlantic Current. Using the ventilated thermocline model several …

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Optical Efficiency Factors Of Free-Living Marine Bacteria: Influence Of Bacterioplankton Upon The Optical Properties And Particulate Organic Carbon In Oceanic Waters, André Morel, Yu-Hwan Ahn Jan 1990

Optical Efficiency Factors Of Free-Living Marine Bacteria: Influence Of Bacterioplankton Upon The Optical Properties And Particulate Organic Carbon In Oceanic Waters, André Morel, Yu-Hwan Ahn

Journal of Marine Research

Free-living coccoid bacteria have been repeatedly isolated from the Mediterranean Sea and then cultured in detritus- and predator-free seawater, either unenriched or slightly nutrient-supplemented. The modal diameter of these cultured cells was in the 0.5 to 1 μm range. The spectral values (within the 400–750 nm λ-range) of absorption, total scattering and backscattering have been determined, together with cell enumeration, size distribution and C–N content. Because of their smallness, bacteria are amenable to simplified theoretical expressions providing their optical efficiency factors. Experimental data are in remarkable quantitative agreement with theoretical predictions. As expected, scattering is wavelength (λ−2) …

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A Mechanistic View Of The Particulate Biodiffusion Coefficient: Step Lengths, Rest Periods And Transport Directions, R. A. Wheatcroft, P. A. Jumars, C. R. Smith, A. R. M. Nowell Jan 1990

A Mechanistic View Of The Particulate Biodiffusion Coefficient: Step Lengths, Rest Periods And Transport Directions, R. A. Wheatcroft, P. A. Jumars, C. R. Smith, A. R. M. Nowell

Journal of Marine Research

We link specific mechanisms of biogenous sediment mixing with the commonly used bioturbation coefficient (Db) that describes their bulk effects. Using an isotropic, stationary, unbiased random walk model we mechanistically decompose the particulate bioturbation coefficient into the fundamental dimensions of length and time. The result shows that Db depends directly on the square of the distance particles are moved (step length) and inversely on the elapsed time between movements (rest period). This new decomposition in terms of explicit mechanisms (i.e., animal activities), leads to scaling arguments that large, deposit feeding animals will in nearly all cases …

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On The Influence Of The Continental Slope On The Western Boundary Layer: The Enhanced Transport And Recirculation, Zhengyu Liu Jan 1990

On The Influence Of The Continental Slope On The Western Boundary Layer: The Enhanced Transport And Recirculation, Zhengyu Liu

Journal of Marine Research

Quasi-geostrophic theory is used to study the effect of a continental slope on the Western Boundary Layer. The compression of the vortex tubes by the slope results in a strong northward boundary current called the Continental Slope Boundary Current (hereafter CSBC). On the β-plane, for a reasonably high slope, we find a strong barotropic recirculation which enhances the total transport of the Western Boundary Current significantly. The two-layer model further shows that the CSBC is trapped in the lower layer. In oceans with very deep lower layers, the CSBC transport increases dramatically. Consequently, even for a very weak lower layer …

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Hydrography And Circulation Off The West Coast Of India During The Southwest Monsoon 1987, S. R. Shetye, A. D. Gouveia, S. S. C. Shenoi, D. Sundar, G. S. Michael, A. M. Almeida, K. Santanam Jan 1990

Hydrography And Circulation Off The West Coast Of India During The Southwest Monsoon 1987, S. R. Shetye, A. D. Gouveia, S. S. C. Shenoi, D. Sundar, G. S. Michael, A. M. Almeida, K. Santanam

Journal of Marine Research

During June–August 1987 thirteen hydrographic sections, each approximately perpendicular to the coast, covered the coastal region off western India. The southernmost section showed occurrence of upwelling, the nearshore surface temperature being about 2.5°C lower than farther offshore. There was a shallow (approximately 75 to 100 m deep) equatorward surface current, below which there were signatures of downwelling indicative of a poleward undercurrent hugging the continental slope. T-S characteristics showed that the undercurrent carried low salinity water found in the southwestern Bay of Bengal. Conditions similar to those found at this section existed up to around 15N but the intensity of …

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Early Diagenesis And Recycling Of Biogenic Debris At The Seafloor, Santa Monica Basin, California, Richard A. Jahnke Jan 1990

Early Diagenesis And Recycling Of Biogenic Debris At The Seafloor, Santa Monica Basin, California, Richard A. Jahnke

Journal of Marine Research

Seafloor recycling of organic materials in Santa Monica Basin, California was examined through in situ benthic chamber experiments, shipboard whole-core incubations and pore water studies. Mass balance calculations indicate that the data are internally consistent and that the estimated benthic exchange rates compare well with those derived from deep, moored conical sediment traps and hydrographic modeling. Pore water and benthic flux observations indicate that the metabolizable organic matter at the seafloor must be composed of at least two fractions of very different reactivities. While the majority of reactive organic compounds degrade quickly, with a half-life of <6.5 years, ¼ of the total metabolizable organic matter appears to react more slowly, with a half-life on the order of 1700 years. Down-core changes in pore water sulfate and titration alkalinity are not explained by stoichiometric models of organic matter diagenesis and suggest that reactions not considered previously must be influencing the pore water concentrations. Measured recycling and burial rates indicate that 43% of the organic carbon reaching the basin seafloor is permanently buried. The results for Santa Monica Basin are compared to those reported for other California Borderland Basins that differ in sedimentation rate and bottom water oxygen content. Organic carbon burial rates for the Borderland Basins are strongly correlated with total organic carbon deposition rate and bulk sedimentation rate. No significant correlation is observed between carbon burial and bottom water oxygen, extent of oxic mineralization and sediment mixing. Thus, for the California Borderlands, it appears that carbon burial rates are primarily controlled by input rates and not by variations in preservation.

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The Evolution Of Salt Fingers In Inertial Wave Shear, Eric Kunze Jan 1990

The Evolution Of Salt Fingers In Inertial Wave Shear, Eric Kunze

Journal of Marine Research

Shadowgraph profiles collected in the thermohaline staircase east of Barbados reveal nearly-horizontal banding—unlike the vertical banding that has been observed in other fingering-favorable parts of the ocean. A plausible interpretation of this optical microstructure is that vertical shear is tilting over fingers. This paper presents a model for shear-tilting of salt fingers. The Ri = 6 inertial wave shears observed in C-SALT would tilt over and damp out square planform (kx = ky) fingers so rapidly that they could not produce significant fluxes. Vertical sheets aligned with the shear (ky = 0) would behave …

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The Mesoscale Variability Of The Sea Surface Temperature: An Analytical And Numerical Mode, Patrice Klein, Bach Lien Hua Jan 1990

The Mesoscale Variability Of The Sea Surface Temperature: An Analytical And Numerical Mode, Patrice Klein, Bach Lien Hua

Journal of Marine Research

This study examines the emergence and evolution of a mesoscale sea surface temperature (SST) variability induced by a uniform and impulsive wind stress when an embedding quasigeostrophic (QG) flow is present. The SST variability which is triggered by the mixed-layer deepening closely resembles some characteristic properties of the QG flow, namely either the subsurface temperature or relative vorticity, depending on the amplitude of the deepening. The SST variance can have the same order of magnitude as the subsurface temperature variance. Within 10 days, the SST field, which is stirred only by the horizontal QG flow, displays a rapid spectral evolution …

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Deep Western Boundary Current Variability At Cape Hatteras, Robert S. Pickart, D. Randolph Watts Jan 1990

Deep Western Boundary Current Variability At Cape Hatteras, Robert S. Pickart, D. Randolph Watts

Journal of Marine Research

Data from an array of inverted echo sounders and bottom current meters off Cape Hatteras, where the Gulf Stream and Deep Western Boundary Current (DWBC) cross each other, are analyzed to investigate the deep components of flow. While the mean flow is to the southwest with the DWBC, the observed temporal variability is dominated by energetic 40 day topographic Rossby waves. By optimally weighting the individual deep current meter measurements, the deep flow is averaged across the wavelength of the 40 day wave, thereby reducing the wave signal and revealing variations of the spatially averaged DWBC. The DWBC fluctuations are …

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Physical, Chemical And Biological Structure Of A Coastal Eddy Near Cape Mendocino, Thomas L. Hayward, Arnold W. Mantyla Jan 1990

Physical, Chemical And Biological Structure Of A Coastal Eddy Near Cape Mendocino, Thomas L. Hayward, Arnold W. Mantyla

Journal of Marine Research

We sampled mesoscale physical, chemical and biological structure in the coastal region of northern California in May, 1987. The circulation was dominated by an equatorward-flowing coastal jet and by a set of mesoscale eddies. High-velocity flow in the core of the coastal jet was composed of low-salinity, low-nutrient water, Cyclonic coastal eddies were observed near Cape Mendocino and Pt. Arena. The Cape Mendocino eddy is examined in detail. This eddy is a common feature which was present both before and after the spring transition, suggesting a relatively weak coupling between the eddy and the local wind field.The coastal circulation strongly …

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The Effect Of Blood Loss During Surgery On The Pharmacokinetics Of Perioperative Antibiotic Prophylaxis, James Anthony Armstrong Jan 1990

The Effect Of Blood Loss During Surgery On The Pharmacokinetics Of Perioperative Antibiotic Prophylaxis, James Anthony Armstrong

Yale Medicine Thesis Digital Library

No abstract provided.

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Analysis Of Fetal Globin Gene Expression In Kuwaitis With Sickle Cell Disease, Ann V. Arthur Jan 1990

Analysis Of Fetal Globin Gene Expression In Kuwaitis With Sickle Cell Disease, Ann V. Arthur

Yale Medicine Thesis Digital Library

No abstract provided.

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Dissipative Dynamics Of Western Boundary Currents, Paola Cessi, R. Vance Condie, W. R. Young Jan 1990

Dissipative Dynamics Of Western Boundary Currents, Paola Cessi, R. Vance Condie, W. R. Young

Journal of Marine Research

We investigate the steady barotropic circulation patterns driven by inflow-outflow boundary conditions on a rectangular β-plane domain. An inertial jet enters the domain in the southwest corner and a broad eastward outflow is prescribed at the eastern boundary. On the western wall there is no mass flux and no slip.With weak viscosity, ν the western boundary jet ?overshoots? northward, beyond the latitude band of the eastern outflow. As the viscosity is reduced the length of this overshoot increases as ν−2/3, before the jet gradually peels away from the western wall, plunges southward and eventually turns eastward. Away …

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Covariability Of Dissolved Oxygen With Physical Processes In The Summertime Chesapeake Bay, Lawrence P. Sanford, Kevin G. Sellner, Denise L. Breitburg Jan 1990

Covariability Of Dissolved Oxygen With Physical Processes In The Summertime Chesapeake Bay, Lawrence P. Sanford, Kevin G. Sellner, Denise L. Breitburg

Journal of Marine Research

Long, rapidly sampled time series measurements of dissolved oxygen, temperature, salinity, currents, winds, tides, and insolation were collected during the summer of 1987 across the mesohaline Chesapeake Bay. Analyses of the data show that short term variability of dissolved oxygen was both large and spatially heterogeneous. Time scales of variability ranged from the longest period fluctuations resolved (several days) to the sampling interval (several minutes). The largest variability was associated with large amplitude, wind and tide forced lateral internal oscillations of the pycnocline in the mainstem of the Bay. These resulted in advection of saline, hypoxic water from below the …

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On The Generation And Propagation Of Rossby Waves In An Ocean With A Zonally Shoaling Mixed Layer, M. S. Darby, A. J. Willmott Jan 1990

On The Generation And Propagation Of Rossby Waves In An Ocean With A Zonally Shoaling Mixed Layer, M. S. Darby, A. J. Willmott

Journal of Marine Research

This paper presents the theory for freely propagating and forced Rossby waves in a continuously stratified ocean where the bouyancy frequency, N, varies with longitude and depth. In this study zonal variations in N occur because the climatological mixed layer depth, h, varies with longitude.With the assumption that changes in h occur on a length scale which is large compared to a horizontal wavelength the free modes on a β-plane are examined. It is found that realistic mixed layer depth changes can cause amplitude modulations, the largest amplitudes occurring where the mixed layer is shallowest. The requirement …

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Identification Of Rna Splicing Errors Resulting In Human Ornithine Transcarbamylase Deficiency, Russ P. Carstens Jan 1990

Identification Of Rna Splicing Errors Resulting In Human Ornithine Transcarbamylase Deficiency, Russ P. Carstens

Yale Medicine Thesis Digital Library

No abstract provided.

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Effect Of Low Temperature On The Trafficking Of 215 Kd Mannose-6-Phosphate/Igf-Ii Receptors In Rat Clone 9 Hepatocytes, Beverly Jean Stoute Jan 1990

Effect Of Low Temperature On The Trafficking Of 215 Kd Mannose-6-Phosphate/Igf-Ii Receptors In Rat Clone 9 Hepatocytes, Beverly Jean Stoute

Yale Medicine Thesis Digital Library

No abstract provided.

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Causes Of Resistant Hypertension In Patients Referred To A Tertiary Care Clinic, Marko Yakovlevitch Jan 1990

Causes Of Resistant Hypertension In Patients Referred To A Tertiary Care Clinic, Marko Yakovlevitch

Yale Medicine Thesis Digital Library

No abstract provided.

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An Evaluation Of Tendon Healing Using Magnetic Resonance Imaging And A Standard Physical Assessment, Victoria Lynette Barber Jan 1990

An Evaluation Of Tendon Healing Using Magnetic Resonance Imaging And A Standard Physical Assessment, Victoria Lynette Barber

Yale Medicine Thesis Digital Library

No abstract provided.

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The Effects Of Cyclosporine On Bone Volume And Bone Formation Rate : A Dose Response Histomorphometric Analysis In The Rat Model, Douglas Marc Freedman Jan 1990

The Effects Of Cyclosporine On Bone Volume And Bone Formation Rate : A Dose Response Histomorphometric Analysis In The Rat Model, Douglas Marc Freedman

Yale Medicine Thesis Digital Library

No abstract provided.

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The Effects Of Implementing A Non-Smoking Policy On An Inpatient Psychiatric Service, Robin Deborah Sprung Jan 1990

The Effects Of Implementing A Non-Smoking Policy On An Inpatient Psychiatric Service, Robin Deborah Sprung

Yale Medicine Thesis Digital Library

No abstract provided.

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Annual Report 1998, Government Of Japan: Deposit Insurance Corporation Jan 1990

Annual Report 1998, Government Of Japan: Deposit Insurance Corporation

Documents

No abstract provided.

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The Risk Of Carotid Endarterectomy In The Elderly : An Application Of Claims Based Research, Neil Andrew Solomon Jan 1990

The Risk Of Carotid Endarterectomy In The Elderly : An Application Of Claims Based Research, Neil Andrew Solomon

Yale Medicine Thesis Digital Library

No abstract provided.

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The Effects Of Interleukin-1, Granulocyte Macrophage Colony-Stimulating Factor, And Tumor Necrosis Factor-Α On Cultured Human Langerhans Cells And Cortical Thymocytes, Steven Andrew Kolenik Iii Jan 1990

The Effects Of Interleukin-1, Granulocyte Macrophage Colony-Stimulating Factor, And Tumor Necrosis Factor-Α On Cultured Human Langerhans Cells And Cortical Thymocytes, Steven Andrew Kolenik Iii

Yale Medicine Thesis Digital Library

No abstract provided.

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Yale University School Of Medicine, Yale-New Haven Medical Center 1990-1991, Yale School Of Medicine Department Of Surgery Jan 1990

Yale University School Of Medicine, Yale-New Haven Medical Center 1990-1991, Yale School Of Medicine Department Of Surgery

Yale Department of Surgery Bulletins

Annual report for 1990-1991.

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Recirculation And Separation Of Boundary Currents, Paola Cessi Jan 1990

Recirculation And Separation Of Boundary Currents, Paola Cessi

Journal of Marine Research

An inertial multi-layer model of the recirculation gyres surrounding a separated boundary current is presented. The boundary current is defined to be separated when the upper layer thickness vanishes. The strong eastward flow found at the outcrop causes the circulation to extend to the bottom through baroclinic instability. In order to decrease the vertical shear responsible for the instability, the deep flow must also have maximum eastward velocity at the outcrop latitude. Thus the deep flow to the north of the outcrop (where no upper fluid is present) must move so as to keep velocity continuous. The eastward flowing deep …

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Double-Diffusive Convection With Imposed Vertical Mass Flux, R. Krishnamurti, Y. Zhu Jan 1990

Double-Diffusive Convection With Imposed Vertical Mass Flux, R. Krishnamurti, Y. Zhu

Journal of Marine Research

Vertical advection and double-diffusive convection are both processes affecting the stratification of the oceans. The effect of vertical advection on double-diffusive convection is investigated by considering the situation in which a horizontal layer of fluid has imposed upon it a destabilizing vertical temperature gradient, a stabilizing vertical salinity gradient and a uniform vertical mass flux. The effect of the imposed vertical mass flux is to remove the stabilizing salt gradient, but not the destabilizing temperature gradient over most of the depth of the layer. This arises from the fact that heat diffuses much more quickly than does salt. The Peelet …

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The Thermocline As An "Internal Boundary Layer", Rick Salmon Jan 1990

The Thermocline As An "Internal Boundary Layer", Rick Salmon

Journal of Marine Research

In this paper, we analyze one-, two- and three-dimensional numerical solutions of a simple, inertia-less ocean circulation model. The solutions, which all approach a steady state, demonstrate that, in the limit of vanishing thermal diffusivity κ, a front of thickness κ1/2, identifiable with the thermocline, spontaneously appears at a location anticipated by simple arguments that treat the front as an "internal boundary layer." The temperature and velocity are generally discontinuous across the front, but the velocity component normal to the front is zero. In the asymptotic limit of vanishing diffusivity, the temperature has no vertical variation within …

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Interaction Between Internal Tides And Energetic Fluxes Across The Atmosphere-Ocean Interface Over A Continental Shelf Break, R. Mazé, J. Y. Le Tareau Jan 1990

Interaction Between Internal Tides And Energetic Fluxes Across The Atmosphere-Ocean Interface Over A Continental Shelf Break, R. Mazé, J. Y. Le Tareau

Journal of Marine Research

Satellite infra-red images taken from April-May to September-October often show persistent ribbons of cool water along the European continental slope, from West Ireland to South-West Brittany (Pingree and Mardell, 1981; Le Tareau et al., 1983; Mazé, 1983; Mazé et al., 1986). The cooling increases northwestward and follows almost exactly the top of the shelf break. This effect appears to be connected with the increase in intensity of the baroclinic internal tide field. A global model is constructed to simulate the cooling process above the edge by interaction between internal tide waves and mixing. First, a three layer model …

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Retroflection And Leakage In The North Brazil Current: Critical Point Analysis, G. T. Csanady Jan 1990

Retroflection And Leakage In The North Brazil Current: Critical Point Analysis, G. T. Csanady

Journal of Marine Research

In an attempt to throw light on the complex flow pattern of the North Brazil Current near its point of separation from the coast, the flow in the neighborhood of boundary- and internal stagnation points ("critical points") has been analyzed. The underlying hypothesis is that fluid masses of widely different potential vorticity come in contact near such points. In a one-and-a-half layer idealization of inertial, frictionless flow the key control parameter is the ratio of potential vorticities of the converging fluids. This determines the angle of flow after separation, and, for given buoyancy and depth scale, the volume of each …

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