Open Access. Powered by Scholars. Published by Universities.®

Digital Commons Network™

Open Access. Powered by Scholars. Published by Universities.®

Yale University

Discipline
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 28051 - 28080 of 33853

Full-Text Articles in Entire DC Network

The Dynamics Of Near-Bed Seston Flux And Suspension-Feeding Benthos, D. K. Muschenheim Jan 1987

The Dynamics Of Near-Bed Seston Flux And Suspension-Feeding Benthos, D. K. Muschenheim

Journal of Marine Research

Benthic suspension feeders depend on the fluid medium for their supply of edible particles. The horizontal flux of organic seston is a function of the interaction of particles of varying densities with the near-bed velocity field. Analytical and numerical models of this process predict that the shape of the flux profile varies with flow rate, bottom roughness and particle settling velocity. Bulk horizontal particle flux may either decrease or increase with height above the bed. Flume experiments with natural sediments from Eastern Passage, Nova Scotia confirmed the trends predicted by the model. In a complex suspension, denser, inorganic particles have …

Go to article

Penetrating Outflows And The Dam-Breaking Problem, Doron Nof Jan 1987

Penetrating Outflows And The Dam-Breaking Problem, Doron Nof

Journal of Marine Research

A new analytical method for computing the speed at which the nose of a rotating intrusion advances along a straight coast is proposed. The nonlinear model includes two active layers; the width of the basin in which the intrusion advances is taken to be finite. Friction is assumed to be small but the motions near the leading edge are not constrained to be quasi-geostrophic.In contrast to previous models (Stern et al., 1982; Kubokawa and Hanawa, 1984a, b) which rely on the assumption that the current head behaves like a long wave and the flow is hydrostatic, the propagation rate …

Go to article

A Model For The Inertial Recirculation Of A Gyre, Richard J. Greatbatch Jan 1987

A Model For The Inertial Recirculation Of A Gyre, Richard J. Greatbatch

Journal of Marine Research

This paper considers the "time-mean" circulation of wind-driven ocean gyres in the limit referred to as "inertial" or "almost-free." In this limit, potential vorticity is conserved following the flow with sources and sinks of potential vorticity balancing in an integral sense around the gyre. Approximate analytic solutions are obtained for a continuously stratified quasi-geostrophic ocean by neglecting the relative vorticity in the gyre interiors. The solutions have features similar to those found in the western part of ocean basins both in eddy-resolving numerical models and in observations. In particular, a deep westward recirculation, such as proposed by Worthington (1976) for …

Go to article

A Model For The Dynamics Of Nutrients And Oxygen In The Baltic Proper, Anders Stigebrandt, Fredrik Wulff Jan 1987

A Model For The Dynamics Of Nutrients And Oxygen In The Baltic Proper, Anders Stigebrandt, Fredrik Wulff

Journal of Marine Research

A horizontally integrated, time-dependent physical-biogeochemical model of high vertical resolution has been developed for the Baltic Sea proper. A seasonal pycnocline model computes the physical state of the mixed surface layer. Below this is an advective-diffusive model. The vertical advection is caused by a time-dependent, entraining bottom current which transports dense seawater into the system. The vertical distributions of volumes and sediment areas are accounted for by the use of the hypsographic function of the system. The chemical/biological processes controlling the distributions of nitrogen and oxygen are modelled as follows: Primary production is controlled by light, temperature, nutrients and density …

Go to article

The Influence Of Planetary Rotation On Oceanic Double-Diffusive Fluxes, Dan Kelley Jan 1987

The Influence Of Planetary Rotation On Oceanic Double-Diffusive Fluxes, Dan Kelley

Journal of Marine Research

Does planetary rotation inhibit double-diffusive fluxes of heat and salt in oceanic thermohaline staircases? The Taylor number Ta, which measures the effect of planetary rotation on convection, is O(1) for laboratory diffusive staircases O(104) for oceanic diffusive staircases. Does this mean that laboratory-based flux laws are inapplicable in the ocean? Lacking flux measurements in double-diffusive systems, these questions are addressed using an analogy between double-diffusive convection and thermal convection. It is shown that Ta is an inappropriate parameter, and that rotating thermal fluxes collapse onto a simple curve when a new Taylor number Tano-slip …

Go to article

Temporal Variability And The Relationship Between Benthic Meiofaunal And Microbial Populations Of A Natural Coastal Petroleum Seep, Paul A. Montagna, James E. Bauer, Jon Toal, Dane Hardin, Robert B. Spies Jan 1987

Temporal Variability And The Relationship Between Benthic Meiofaunal And Microbial Populations Of A Natural Coastal Petroleum Seep, Paul A. Montagna, James E. Bauer, Jon Toal, Dane Hardin, Robert B. Spies

Journal of Marine Research

Previous studies of the Isla Vista petroleum seep in the Santa Barbara Channel found much higher abundances of macrofauna and concentrations of adenosine triphosphate (ATP) in sediments near petroleum seepage compared to those from nonseep areas. To further assess the possible effect of petroleum on organisms at the base of benthic food webs, population abundances of meiobenthos and their suspected microbial food (bacteria and diatoms) were measured biweekly for one year at three stations with differing petroleum exposure. Determinations of suspended particulate matter and the abundance and gut contents of juvenile fishes were also made at seep and nonseep stations. …

Go to article

Continental-Shelf-Scale Model Of The Leeuwin Current, R. O. R. Y. Thompson Jan 1987

Continental-Shelf-Scale Model Of The Leeuwin Current, R. O. R. Y. Thompson

Journal of Marine Research

A simple model is presented for the poleward eastern boundary current (the Leeuwin Current) off Western Australia. For continental-shelf length-scales and seasonal time-scales, the advective and time-derivative terms are small, and water flows onto the shelf until a sufficient cross-shelf pressure gradient is set up to push the same flux back. In a rotating system, the return flux takes place in a frictional (Ekman) layer at the bottom, and is synonymous with a near-bottom longshore current νB, from−CD|νB|νB = ∫O−H 1/ρ ∂p/∂y dz + u2 …

Go to article

Accurately Monitoring The Florida Current With Motionally Induced Voltages, Peter Spain, Thomas B. Sanford Jan 1987

Accurately Monitoring The Florida Current With Motionally Induced Voltages, Peter Spain, Thomas B. Sanford

Journal of Marine Research

A new experimental technique for appraising how accurately submarine-cable (subcable) voltages monitor oceanic volume transport is presented and then used to study voltages induced by the northern Florida Current. Until recently, subcable voltages have been largely dismissed as an oceanographic tool because their interpretation can be ambiguous. They depend upon the transport field, the electrical conductance of the environment, and the mutual spatial distribution of these two quantities. To examine how these three factors affect subcable voltages at a particular site, we combine data from two different velocity profilers: XCP and PEGASUS. These instruments provide vertical profiles of velocity, temperature, …

Go to article

Variability Of Diatom Species Populations: From Days To Years, Sargun A. Tont Jan 1987

Variability Of Diatom Species Populations: From Days To Years, Sargun A. Tont

Journal of Marine Research

Based on over 300,000 individual measurements, temporal and spatial variations in diatom abundances and related atmospheric and oceanic variables have been investigated for two locations near the coast of southern California. Time scale of periods investigated ranged from days to 10 years; variability over centuries can be reconstructed from climate records. The results of principal component analysis based on weekly averages indicated that eigenvectors at Scripps and Pt. Hueneme piers, nearly 200 km apart, were similar; removal of seasonal cycles (by calculating anomalies) did not significantly alter these eigenvectors. Principal components derived from matrices based on weekly averages of 20, …

Go to article

Components Of The Zooplankton Production Cycle In The Temperate Ocean, Cabell S. Davis Jan 1987

Components Of The Zooplankton Production Cycle In The Temperate Ocean, Cabell S. Davis

Journal of Marine Research

Components of the zooplankton production cycle (assimilation, respiration, and predation) on Georges Bank were analyzed using three models of increasing complexity, i.e., total biomass (Riley, 1947), size-structure (Huntley and Boyd, 1984) and species population (Davis, 1984a). Other temperate marine areas with seasonal cycles in temperature similar to Georges Bank were identified and available data on zooplankton biomass and species cycles were found. For Georges Bank, the species level model, based on well-defined empirical relationships between temperature, development rate, and fecundity, revealed that highest production occurs by small animals during warmest months (e.g., September), when biomass is low. By contrast, the …

Go to article

Some Aspects Of The Oxygen-Deficient Conditions And Denitrification In The Arabian Sea, S. W. A. Naqvi Jan 1987

Some Aspects Of The Oxygen-Deficient Conditions And Denitrification In The Arabian Sea, S. W. A. Naqvi

Journal of Marine Research

Utilizing a fairly large amount of recently collected data, some outstanding questions concerning the Arabian Sea denitrification problem are addressed. The true levels of dissolved oxygen, determined colorimetrically, are about an order of magnitude lower than those reported previously from the oxygen minimum zone. Lateral advection of waters from south into the oxygen-deficient layer is suggested by the presence of an intermediate oxygen maximum discernible even at very low oxygen levels. An unusual minimum in nitrate and a corresponding maximum in nitrite are observed occasionally within the depth range 700–1,200 m at several stations, generally located in the northeastern Arabian …

Go to article

Supervision, Incentives, And The Optimum Size Of A Labor- Managed Firm, Justin Yifu Lin Jan 1987

Supervision, Incentives, And The Optimum Size Of A Labor- Managed Firm, Justin Yifu Lin

Discussion Papers

No abstract provided.

Go to article

The Household Responsibility System Reform In China: A Peasant’S Institutional Choice, Justin Yifu Lin Jan 1987

The Household Responsibility System Reform In China: A Peasant’S Institutional Choice, Justin Yifu Lin

Discussion Papers

No abstract provided.

Go to article

An Investigation Of Novel Flourescent Antimetabolites As Potential Molecular Probes In Neoplastic Cells, Jeffrey Samuel Barkin Jan 1987

An Investigation Of Novel Flourescent Antimetabolites As Potential Molecular Probes In Neoplastic Cells, Jeffrey Samuel Barkin

Yale Medicine Thesis Digital Library

No abstract provided.

Go to article

The Relationship Between Myocardial Blood Flow Reduction And Heterogeneity Of Ischemic Injury : Following Experimental Coronary Artery Occlusion In The Canine Model, Mark Ian Block Jan 1987

The Relationship Between Myocardial Blood Flow Reduction And Heterogeneity Of Ischemic Injury : Following Experimental Coronary Artery Occlusion In The Canine Model, Mark Ian Block

Yale Medicine Thesis Digital Library

No abstract provided.

Go to article

Deciding For Others : Rights And Responsiblities In Medical Ethics, Patricia Mary Powell Jan 1987

Deciding For Others : Rights And Responsiblities In Medical Ethics, Patricia Mary Powell

Yale Medicine Thesis Digital Library

No abstract provided.

Go to article

Echocardiographic Study Of Myocardial Performance After Exercise In Type I Diabetes Mellitus, Robert R. Englander Jan 1987

Echocardiographic Study Of Myocardial Performance After Exercise In Type I Diabetes Mellitus, Robert R. Englander

Yale Medicine Thesis Digital Library

No abstract provided.

Go to article

Clonidine And Naltrexone : Rapid Treatment Of Opioid Withdrawal In The Outpatient Setting, Eugenia Marie Vining Jan 1987

Clonidine And Naltrexone : Rapid Treatment Of Opioid Withdrawal In The Outpatient Setting, Eugenia Marie Vining

Yale Medicine Thesis Digital Library

No abstract provided.

Go to article

Pseudomonas Cepacia Colonization In Cystic Fibrosis : Mortality, Predictors Of Poor Outcome, And Effect On Pulmonary Function, Linda Orkin Lewin Jan 1987

Pseudomonas Cepacia Colonization In Cystic Fibrosis : Mortality, Predictors Of Poor Outcome, And Effect On Pulmonary Function, Linda Orkin Lewin

Yale Medicine Thesis Digital Library

No abstract provided.

Go to article

Structural Homology Of The Gabaa/Benzodiazepine Receptor As Demonstrated By Monoclonal Antibodies And Limited Proteolysis, Robert Thomas Malison Jan 1987

Structural Homology Of The Gabaa/Benzodiazepine Receptor As Demonstrated By Monoclonal Antibodies And Limited Proteolysis, Robert Thomas Malison

Yale Medicine Thesis Digital Library

No abstract provided.

Go to article

The Role Of Cyclosporine In Liver Disease After Renal Transplantation, Terry J. Watnick Jan 1987

The Role Of Cyclosporine In Liver Disease After Renal Transplantation, Terry J. Watnick

Yale Medicine Thesis Digital Library

No abstract provided.

Go to article

Computer Aided Evaluation Of Early Neoplasms, Ian Ainsworth Cook Jan 1987

Computer Aided Evaluation Of Early Neoplasms, Ian Ainsworth Cook

Yale Medicine Thesis Digital Library

No abstract provided.

Go to article

On The Dynamics Of The California Current System, Julian P. Mccreary Jr., Pijush K. Kundu, Shenn-Yu Chao Jan 1987

On The Dynamics Of The California Current System, Julian P. Mccreary Jr., Pijush K. Kundu, Shenn-Yu Chao

Journal of Marine Research

The dynamics of the California Current system are studied using two ocean models, one with a shelf and one without. Both models are viscid and linearized about a background density field Pb(Z), Solutions are forced by steady and annually periodic winds with and without curl, and by an idealization of the observed wind field off California. Solutions forced by a steady, equatorward, curl-free wind τy all have an equatorward surface coastal jet and a poleward undercurrent. Due to the β-effect and horizontal mixing, the circulation is not necessarily confined within a Rossby radius of …

Go to article

On The Energetics Of The Gulf Stream At 73w, T. Rossby Jan 1987

On The Energetics Of The Gulf Stream At 73w, T. Rossby

Journal of Marine Research

From September 1980 through May 1983 a series of nineteen sections of velocity profiles were obtained across the Gulf Stream 200 km northeast of Cape Hatteras. By decomposing the velocity and temperature observations into mean and fluctuating fields in two coordinate systems, geographic (or Eulerian) and 'stream' coordinates, it is shown that at least ⅔ of the eddy kinetic and potential energy is caused by the meandering of a well defined baroclinic front with a structure that is nearly independent of space and time. It is also shown that more than 95% of the kinetic energy of the front can …

Go to article

Single-Particle Dispersion, Lagrangian Structure Function And Lagrangian Energy Spectrum In Two-Dimensional Incompressible Turbulence, Armando Babiano, Claude Basdevant, Pascal Le Roy, Robert Sadourny Jan 1987

Single-Particle Dispersion, Lagrangian Structure Function And Lagrangian Energy Spectrum In Two-Dimensional Incompressible Turbulence, Armando Babiano, Claude Basdevant, Pascal Le Roy, Robert Sadourny

Journal of Marine Research

The single-particle dispersion, Lagrangian structure functions and Lagrangian energy spectra characteristic of two-dimensional incompressible turbulent flows are investigated theoretically and numerically. The domain of validity of the classical asymptotic estimates is extended; it is shown in particular that the asymptotic behavior of the single-particle dispersion at small times remains valid throughout the whole self-similar range when the Lagrangian energy spectrum is steeper than ω−1. Straightforward estimates of the Lagrangian integral time scale TL and the diffusion coefficient at large times K, based on energy and enstrophy, are proposed; to some extent, they remain valid locally, which …

Go to article

Lagrangian Properties Of Eddy Fields In The Northern North Atlantic As Deduced From Satellite-Tracked Buoys, W. Krauss, C. W. Böning Jan 1987

Lagrangian Properties Of Eddy Fields In The Northern North Atlantic As Deduced From Satellite-Tracked Buoys, W. Krauss, C. W. Böning

Journal of Marine Research

One hundred and thirteen satellite-tracked buoys have been used during their first 5 months after deployment in order to calculate Lagrangian statistics of the eddy field in the northern North Atlantic between Newfoundland and the Canary basin. r.m.s. velocities are isotropic and increase from southeast to northwest. Lagrangian integral time scales, derived both from correlation function and from dispersion, are slightly anisotropic and decrease from the subtropics toward the North Atlantic Current. Time scale is inversely proportional to the r.m.s. velocity of the eddies. Eddy length scale is approximately constant in the North Atlantic. Dispersion is in good agreement with …

Go to article

A Least-Squares Fit Of The Advective-Diffusive Equations To Levitus Atlas Data, Nelson G. Hogg Jan 1987

A Least-Squares Fit Of The Advective-Diffusive Equations To Levitus Atlas Data, Nelson G. Hogg

Journal of Marine Research

The distributions of temperature, oxygen and potential vorticity on two isopycnals and the geostrophic shear between them are used to obtain the flow fields and diffusivities through a least-squares inversion of the steady state, advective-diffusive equations. The source of the data is the Levitus Atlas, and the two isopycnals are located in a 24° square centered on the Mediterranean Water tongue in the eastern North Atlantic. One isopycnal is in the thermocline and the other beneath so chosen to be near the level of maximum salinity and temperature anomaly.Although tracer distributions on the two levels are similar, the inversion suggests …

Go to article

Seasonal Fluxes Of Silicoflagellates And Actiniscus In The Subarctic Pacific During 1982-1984, Kozo Takahashi Jan 1987

Seasonal Fluxes Of Silicoflagellates And Actiniscus In The Subarctic Pacific During 1982-1984, Kozo Takahashi

Journal of Marine Research

A seasonal flux study of silicoflagellates and Actiniscus was conducted at subarctic Pacific Station PAPA (50N, 145W; water depth 4200 m) during September, 1982 through August, 1984 using PARFLUX high resolution time series sediment traps deployed at 1000 m and 3800 m depths. The time series sediment trap samples were collected for 4 to 16-day periods depending on the samples; most of the samples were collected for 14 to 16-day periods. From a depth of 3800 m, a total of 47 samples represents a nearly two-year continuous record of the fluxes of silicoflagellate and Actiniscus taxa. An additional 12 samples …

Go to article

Modeling Eddy Transport Of Passive Tracers, Russ E. Davis Jan 1987

Modeling Eddy Transport Of Passive Tracers, Russ E. Davis

Journal of Marine Research

The mean advective and eddy transport of a passive scalar property is examined. Using a theory based on rational approximation of Lagrangian particle statistics, a transport equation relating the mean eddy flux and the mean concentration field Θ is developed. The transport equation is an elaborated advection-diffusion model in which the mean eddy flux is determined by the recent history of the gradient of Θ. The flux law involves an eddy diffusivity which depends on time lag and is defined in terms of fluid particle trajectories. Particle trajectories in simulated geophysical turbulence are used to test the applicability of the …

Go to article

The Importance Of A Plume Of Tidally-Mixed Water To The Biological Oceanography Of The Gulf Of Maine, David W. Townsend, John P. Christensen, David K. Stevenson, Joseph J. Graham, Stanley B. Chenoweth Jan 1987

The Importance Of A Plume Of Tidally-Mixed Water To The Biological Oceanography Of The Gulf Of Maine, David W. Townsend, John P. Christensen, David K. Stevenson, Joseph J. Graham, Stanley B. Chenoweth

Journal of Marine Research

During the warmer months of the year the eastern Gulf of Maine features a plume of cold water which extends from the tidally well-mixed area adjacent to Grand Manan Island at the mouth of the Bay of Fundy southwest along the Maine coast to well beyond Penobscot Bay. Near Grand Manan Island the plume waters are cold (ca. 10°C), nearly vertically isothermal and carry high concentrations of dissolved inorganic nutrients. The analysis of temperature-salinity diagrams and hydrographic vertical section plots indicate that the deeper waters in Jordan Basin, of slope water origin, upwell and contribute a significant fraction of the …

Go to article

First Prev Next Last