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Observations Of Temporal Changes Of Tritium-3he Age In The Eastern North Atlantic Thermocline: Evidence For Changes In Ventilation, Paul E. Robbins, William J. Jenkins Jan 1998

Observations Of Temporal Changes Of Tritium-3he Age In The Eastern North Atlantic Thermocline: Evidence For Changes In Ventilation, Paul E. Robbins, William J. Jenkins

Journal of Marine Research

A compilation of fifteen years of tritium and 3He measurements is used to examine the ventilation of the eastern North Atlantic subtropical gyre with specific emphasis on the temporal character of the tracer age field. A multivariate regression analysis in the form of a spatiotemporal Taylor expansion is applied to observations interpolated onto isopycnal surfaces. The time-dependent component of the tracer age field is found to be statistically significant, explaining approximately 10% of the variance of the tracer age observations in the upper thermocline (σ = 26.5) and increasing to roughly 50% of the variance in the lower thermocline …

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Tidal Mixing And Cross-Frontal Particle Exchange Over A Finite Amplitude Asymmetric Bank: A Model Study With Application To Georges Bank, Changsheng Chen, Robert C. Beardsley Jan 1998

Tidal Mixing And Cross-Frontal Particle Exchange Over A Finite Amplitude Asymmetric Bank: A Model Study With Application To Georges Bank, Changsheng Chen, Robert C. Beardsley

Journal of Marine Research

Tidal mixing, internal wave bores, and cross-bank particle transport over a finite amplitude asymmetric bank are examined using a two-dimensional primitive equation ocean model with Mellor and Yamada (level 2.5) turbulent closure. Driven by the surface M2 tide, the model results show that tidal mixing exhibits temporal and spatial asymmetries on southern and northern flanks of the bank. It is strongest near the bottom around maximum on-bank tidal flow as a result of gravitational instability when denser water is advected upslope over lighter water. A sharp thermal depression occurs on the steep northern flank, which produces large current shear …

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Small Viscosity Behavior Of A Homogeneous, Quasi-Geostrophic, Ocean Circulation Mode, Robert B. Scott, David N. Straub Jan 1998

Small Viscosity Behavior Of A Homogeneous, Quasi-Geostrophic, Ocean Circulation Mode, Robert B. Scott, David N. Straub

Journal of Marine Research

Insensitivity to turbulent closure in the wind-driven nonlinear Stommel-Munk model is addressed theoretically and numerically. The QG energy equation is used to show that, with the assumption that the maximum velocities occur at inertial length scales or smaller, a Sverdrup interior is consistent with the small Rossby number assumption only when the frictional parameters exceed critical values. For frictional parameters smaller than these values, valid solutions must decrease the energy source. This is possible for non-Sverdrup solutions since the energy source is dependent on the solution. The steady-state behavior of the model was investigated via a pseudo-arclength continuation algorithm. Dependence …

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Larval Settlement In Turbulent Pipe Flows, James E. Eckman, David O. Duggins Jan 1998

Larval Settlement In Turbulent Pipe Flows, James E. Eckman, David O. Duggins

Journal of Marine Research

In two experiments, larval settlement was studied within a series of pipes, each containing steady, turbulent, flowing seawater. The study was designed to determine effects of flow (speed, turbulence intensity and wall shear stress) and surface orientation on rates of settlement of larvae of various taxa, and to relate variability in patterns of settlement among orientations and flows to the concomitant variability expected in rates of larval supply or delivery to the pipe walls. Patterns of settlement of all five taxa (the barnacle Balanus spp., the mussel Mytilus trossulus, the serpulid polychaete Pseudochitinopoma occidentalis, the cyclostome bryozoan Tubulipora sp., …

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Cloning, Sequencing And Partial Characterization Of The 5' Flanking Region Of The Mouse Neutrophil Collagenase Gene : Conservation With The Human Neutrophil Collagenase Regulatory Region, Marcoli Cyrille Jan 1998

Cloning, Sequencing And Partial Characterization Of The 5' Flanking Region Of The Mouse Neutrophil Collagenase Gene : Conservation With The Human Neutrophil Collagenase Regulatory Region, Marcoli Cyrille

Yale Medicine Thesis Digital Library

No abstract provided.

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Power And Mysticism In The Introduction Of Anesthesia In Nineteenth Century America, Naomi Strachan Donnelley Jan 1998

Power And Mysticism In The Introduction Of Anesthesia In Nineteenth Century America, Naomi Strachan Donnelley

Yale Medicine Thesis Digital Library

No abstract provided.

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An Analysis Of Issues Surrounding Disclosure Of The Diagnosis Of Human Immunodeficiency Virus Infection To Children, Reshma Ravi Chugani Jan 1998

An Analysis Of Issues Surrounding Disclosure Of The Diagnosis Of Human Immunodeficiency Virus Infection To Children, Reshma Ravi Chugani

Yale Medicine Thesis Digital Library

No abstract provided.

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Modulation Of Atp-Sensitive Potassium Channel Activity By Atp-Binding Cassette Transporters : A Model For Channel Regulation, Tong-Yi Yao Jan 1998

Modulation Of Atp-Sensitive Potassium Channel Activity By Atp-Binding Cassette Transporters : A Model For Channel Regulation, Tong-Yi Yao

Yale Medicine Thesis Digital Library

No abstract provided.

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A Streamtube Model Of Rotating Turbidity Currents, P. W. Emms Jan 1998

A Streamtube Model Of Rotating Turbidity Currents, P. W. Emms

Journal of Marine Research

A rotating turbidity current is modeled as a steady tube of sediment-laden water traversing along and down a uniform slope representing the continental shelf. The model includes parameterizations of erosion of sediment from the seabed into the plume, deposition onto the seafloor, bottom friction, and turbulent entrainment of the overlying ambient seawater. The purpose of the work is to study how these parameterizations affect the path the current takes on the slope and to determine criteria which affect the qualitative behavior of the model solutions. It is found that there are three possible final states to the model. The first …

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The Salt Finger Amplitude In Unbounded T-S Gradient Layers, Melvin E. Stern, Timour Radko Jan 1998

The Salt Finger Amplitude In Unbounded T-S Gradient Layers, Melvin E. Stern, Timour Radko

Journal of Marine Research

Finite amplitude numerical calculations are made for a completely unbounded salt finger domain whose overall vertical "property" gradients (Tz and Sz) are uniform and remain unaltered in time. For diffusivity ratio τ = κS/κT = O (1), Prandtl number ν/κT >> 1, and density ratio R = Tz/Sz > 1 this regime corresponds to a "double gradient" sugar (S)—salt (T) experiment. Two-dimensional pseudo-spectral calculations are made in the vicinity of the minimum critical condition for salt finger instability, viz., small ε ≡ (Rτ)-1 …

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Simulation Of Primary Production And Export Fluxes In The Northwestern Mediterranean Sea, Marina Lévy, Laurent Mémery, Jean-Michel André Jan 1998

Simulation Of Primary Production And Export Fluxes In The Northwestern Mediterranean Sea, Marina Lévy, Laurent Mémery, Jean-Michel André

Journal of Marine Research

A biogeochemical model, BIOMELL (BIOgeochemical Model of the Euphotic Layer of Lodyc), has been developed to simulate the temporal evolution of the main nitrogen stocks and fluxes at the DyFAMed station (Dynamique des Flux Atmospheriques en Mediterranée), located in the Northwestern Mediterranean Sea. This mainly oligotrophic region is characterized by a strong seasonal cycle, and a significant export of dissolved organic matter compared to the particulate export measured by sediment traps. Validation of the model is made using temperature, nitrate and chlorophyll profiles acquired at DyFAMed approximately every month in 1991. Extended datasets from specific years are also used to …

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On The Parameterization Of Eddy Transfer, Part Ii: Tests With A Channel Model, Peter D. Killworth Jan 1998

On The Parameterization Of Eddy Transfer, Part Ii: Tests With A Channel Model, Peter D. Killworth

Journal of Marine Research

In Part I of this paper (Killworth, 1997), a new eddy parameterization scheme was presented. Here, the scheme is tested by comparing its predictions with those of multi-year averages from an eddy-resolving channel model. Its accuracy is similar to that of a tuned version of previous schemes. However, a tuned version of the new parameterization can reproduce both the long-term average of the eddy-resolving solution as well as the initial slumping of a narrow front. Both tuned schemes reproduced the bolus transport well. The new parameterization reproduces the observed feature that the diffusivity is maximal at mid-depth and minimal at …

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Does The Sverdrup Critical Depth Model Explain Bloom Dynamics In Estuaries?, Lisa V. Lucas, James E. Cloern, Jeffrey R. Koseff, Stephen G. Monismith, Janet K. Thompson Jan 1998

Does The Sverdrup Critical Depth Model Explain Bloom Dynamics In Estuaries?, Lisa V. Lucas, James E. Cloern, Jeffrey R. Koseff, Stephen G. Monismith, Janet K. Thompson

Journal of Marine Research

In this paper we use numerical models of coupled biological-hydrodynamic processes to search for general principles of bloom regulation in estuarine waters. We address three questions: What are the dynamics of stratification in coastal systems as influenced by variable freshwater input and tidal stirring? How does phytoplankton growth respond to these dynamics? Can the classical Sverdrup Critical Depth Model (SCDM) be used to predict the timing of bloom events in shallow coastal domains such as estuaries? We present results of simulation experiments which assume that vertical transport and net phytoplankton growth rates are horizontally homogeneous. In the present approach the …

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The Prime Eddy, Adrian P. Martin, Ian P. Wade, Kelvin J. Richards, Karen J. Heywood Jan 1998

The Prime Eddy, Adrian P. Martin, Ian P. Wade, Kelvin J. Richards, Karen J. Heywood

Journal of Marine Research

An intrathermocline lens with strong anticyclonic circulation and cold surface temperature anomaly (–1°C) is reported in the Iceland Basin at 59.1N 20W. The lens is 1000 m thick, 120 km wide and centered on the 27.45 σ0 isopycnal at 700 m. Its influence, through distortion of density surfaces, is felt throughout the 2800 m water column. At the surface this leads to a shallower mixed layer within the eddy which will have an impact on the local planktonic ecology. At a depth of 700 m and a radius of 40 km the eddy circulation has an azimuthal velocity of …

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The Tidal And Subtidal Variations In The Transverse Salinity And Current Distributions Across A Coastal Plain Estuary, Kuo-Chuin Wong, Joy E. Moses-Hall Jan 1998

The Tidal And Subtidal Variations In The Transverse Salinity And Current Distributions Across A Coastal Plain Estuary, Kuo-Chuin Wong, Joy E. Moses-Hall

Journal of Marine Research

The transverse structure in the current and salinity distributions across the mouth of Delaware Bay are examined over the tidal and subtidal time scales. Results show that the across-estuary variation in bathymetry, in the form of a channel-shoal configuration, has a very significant impact on the characteristics of transverse variability. The mean current over the channel is characterized by a strong outflow of low salinity water in the upper layer and a strong inflow of high salinity water in the lower layer, consistent with the density-induced gravitational circulation. The mean flow pattern in the shallow waters over the shoals is …

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Detailed Observations Of The Phytoplankton Spring Bloom In The Stratifying Central North Sea, Hans Van Haren, David K. Mills, Lambertus P. M. J. Wetsteyn Jan 1998

Detailed Observations Of The Phytoplankton Spring Bloom In The Stratifying Central North Sea, Hans Van Haren, David K. Mills, Lambertus P. M. J. Wetsteyn

Journal of Marine Research

Analysis of detailed time series of bio-optical and temperature data from the North Sea supports the view that a minimum level of turbulence is a prerequisite for the onset and maintenance of the phytoplankton spring bloom in shelf seas, which distinguishes these seas from the open ocean. The start of the spring bloom, primarily diatoms, is controlled by the light regime, while its progress is predominantly dependent upon episodic turbulence input following short periods of stratification, which allow the resuspension of a fast sinking (50-200 m day-1) phytoplankton community from the bottom mixing layer. A relationship between turbulence …

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Influences Of Physical Oceanographic Processes On Chlorophyll Distributions In Coastal And Estuarine Waters Of The South Atlantic Bight, P. G. Verity, J. O. Blanton, J. Amft, C. Barans, D. Knott, B. Stender, E. Wenner Jan 1998

Influences Of Physical Oceanographic Processes On Chlorophyll Distributions In Coastal And Estuarine Waters Of The South Atlantic Bight, P. G. Verity, J. O. Blanton, J. Amft, C. Barans, D. Knott, B. Stender, E. Wenner

Journal of Marine Research

Coastal and estuarine waters of the South Atlantic Bight are highly productive, with primary production of 600-700 gC/m2/y. While controls and fate of this production are conceptually well understood, the importance of meteorology and physical circulation processes on phytoplankton has not received equivalent attention. Here, we describe the effects of wind stress and tidal currents on temporal and spatial distributions of phytoplankton biomass represented as chlorophyll a (chl a). Moored instruments were deployed and shipboard sampling was conducted in the North Edisto estuary (South Carolina) and adjacent inner shelf waters during four, two-week field studies in May …

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On The Barotropic Ocean With Bottom Friction, Victor Barcilon Jan 1998

On The Barotropic Ocean With Bottom Friction, Victor Barcilon

Journal of Marine Research

The mathematical problem governing the circulation of a barotropic ocean with bottom friction is re-examined by a procedure which allows us to systematically span the entire region of the parameter space R, ε << 1, where R and ε are the Rossby and 'friction' numbers. The procedure consists in first identifying three dynamically distinct sectors in parameter space. Next, single variable asymptotic expansions are carried out along the boundaries of these sectors. In addition to affording us the opportunity to study the regimes in both of the adjoining sectors, this procedure avoids the possibility of the series becoming disordered. The sector R …

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Generalized Inverse With Shipboard Current Measurements: Tidal And Nontidal Flows In Long Island Sound, Philip S. Bogden, James O'Donnell Jan 1998

Generalized Inverse With Shipboard Current Measurements: Tidal And Nontidal Flows In Long Island Sound, Philip S. Bogden, James O'Donnell

Journal of Marine Research

A simple linear shallow-water model forced by tidal boundary conditions can capture most of the tide height variability in Long Island Sound. In this sense, the tides are easy to model. The modeled tidal currents can be subtracted from measurements in order to obtain estimates of subtidal circulation. But linear shallow-water dynamics is not accurate enough for this purpose. Allowing for dynamical errors with a generalized inverse model leads to improved estimates of tidal and nontidal flow. The analysis provides expected errors for the prior (before inversion) and posterior (after inversion) tidal velocity field. Estimates of the flow field in …

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Seasonal Patterns Of Carbonate Diagenesis In Nearshore Terrigenous Muds: Relation To Spring Phytoplankton Bloom And Temperature, Mark A. Green, Robert C. Aller Jan 1998

Seasonal Patterns Of Carbonate Diagenesis In Nearshore Terrigenous Muds: Relation To Spring Phytoplankton Bloom And Temperature, Mark A. Green, Robert C. Aller

Journal of Marine Research

Pore water saturation state with respect to calcite and aragonite minerals in Long Island Sound sediments fluctuates from saturated and near saturated conditions during late fall, to undersaturated during winter, before slowly changing to supersaturated conditions during late spring. Undersaturation occurs during cold, winter periods when lower rates of ΣCO2 production (low rates of heterotrophic metabolism) and oxidation of reduced minerals such as FeS lower calcium carbonate saturation states. Direct evidence that dissolution of both calcites and aragonite are occurring during this season comes from the simultaneous increases in excess pore water carbonate dissolution products Ca2+, F …

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Intermediate Water Circulation And Ventilation Of The Indian Ocean Derived From Water-Mass Contributions, Yuzhu You Jan 1998

Intermediate Water Circulation And Ventilation Of The Indian Ocean Derived From Water-Mass Contributions, Yuzhu You

Journal of Marine Research

The intermediate water circulation and ventilation of the Indian Ocean is somewhat unique among the world oceans (in terms of the source waters). This has been studied with historical and recently obtained hydrographic data including potential temperature, salinity, dissolved oxygen, phosphate and silicate in a mixing model of applying optimum multiparameter analysis (OMP). The mixing model comprises three source water masses, Antarctic Intermediate Water (AAIW) (applied the transformed AAIW north of the Antarctic frontal zone and central South Indian Ocean), Indonesian Intermediate Water (IIW) and Red Sea Intermediate Water (RSIW) (including the influence of Persian Gulf Intermediate Water). A possible …

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Comparative Diagenesis At Three Sites On The Canadian Continental Margin, Bernard P. Boudreau, Alfonso Mucci, Bjorn Sundby, George W. Lunther, Norman Silverberg Jan 1998

Comparative Diagenesis At Three Sites On The Canadian Continental Margin, Bernard P. Boudreau, Alfonso Mucci, Bjorn Sundby, George W. Lunther, Norman Silverberg

Journal of Marine Research

Diagenesis of carbon, oxygen, nitrogen, and manganese at three sites on the Canadian continental margin is quantitatively compared and contrasted using results from a computer code (CANDI) published by Boudreau (1996a). The data at Station 3 (Cabot Strait) are well explained by the steady state output from CANDI, assuming a porewater balance created by diffusion and reaction only, whereas the data from Stations 4 (Emerald Basin-Scotia Shelf) and 5 (Scotia Slope) are not consistent, in one way or another, with this simple model. The deviations between model and data at Station 4 are best explained by nonsteady-state diagenesis. Model fits …

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An Innovative Curriculum Of Literature And Medicine During Residency Education : Poetry On The Wards, Pieter Aaron Cohen Jan 1998

An Innovative Curriculum Of Literature And Medicine During Residency Education : Poetry On The Wards, Pieter Aaron Cohen

Yale Medicine Thesis Digital Library

No abstract provided.

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Abnormalities In Hepatocyte Endocytosis In Chronic Pancreatitis, Jaimie David Nathan Jan 1998

Abnormalities In Hepatocyte Endocytosis In Chronic Pancreatitis, Jaimie David Nathan

Yale Medicine Thesis Digital Library

No abstract provided.

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Detection Of The Factor V Leiden Mutation In A Nonselected Black Population, Paul Stuart Pottinger Jan 1998

Detection Of The Factor V Leiden Mutation In A Nonselected Black Population, Paul Stuart Pottinger

Yale Medicine Thesis Digital Library

No abstract provided.

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A Five Year Retrospective Study Of Tuberculosis At A Public Hospital In The Ecuadorian Highlands, Eric Gary Shmookler Jan 1998

A Five Year Retrospective Study Of Tuberculosis At A Public Hospital In The Ecuadorian Highlands, Eric Gary Shmookler

Yale Medicine Thesis Digital Library

No abstract provided.

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Annual Economic Report 1998, Bank Of Thailand Jan 1998

Annual Economic Report 1998, Bank Of Thailand

Documents

No abstract provided.

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Psychosocial Factors Associated With Condom Use Among Urban Adolescents, Makunda Abdul Jan 1998

Psychosocial Factors Associated With Condom Use Among Urban Adolescents, Makunda Abdul

Yale Medicine Thesis Digital Library

No abstract provided.

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Linear Theory Of The Effect Of A Sloping Boundary On Circulation In A Homogeneous Laboratory Model, Ross W. Griffiths, George Veronis Jan 1998

Linear Theory Of The Effect Of A Sloping Boundary On Circulation In A Homogeneous Laboratory Model, Ross W. Griffiths, George Veronis

Journal of Marine Research

Griffiths and Veronis (1997) reported observations of the effect of a sloping boundary on the circulation in a sliced-cylinder model of wind-driven circulation in which the flow is driven by the relative rotation of the top lid. A summary of observations for the nearly linear case is given here along with the linear analysis based on the theory of a rotating homogeneous fluid. Good agreement between the two is obtained, and the (straightforward) physics of the system is described.

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Topography And Barotropic Transport Control By Bottom Friction, William K. Dewar Jan 1998

Topography And Barotropic Transport Control By Bottom Friction, William K. Dewar

Journal of Marine Research

The problem of the stratified general circulation in the presence of topography is revisited. The novel effect examined here is that of localized, but large-scale, topographic anomalies on the wind-driven circulation, a problem whose relevance is found in the occurrence of many such features in the open ocean. Using the classical methods of homogenization theory, it is argued that the barotropic transport near topography can come under the direct control of bottom friction. This result differs substantively from either the well-known Sverdrup constraint (which applies to a flatbottomed ocean, or to one with a resting deep layer) or its recent …

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