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The Private Demand For Information And The Effects Of Public Testing Programs: The Case Of Hiv, Michael Boozer, Tomas Philipson

Discussion Papers

No abstract provided.

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Minute Of The Federal Open Market Committee Meeting - January 20-31, 1996, Federal Reserve System: Board Of Governors

Documents

No abstract provided.

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Distinct Year-To-Year Particle Flux Variations Off Cape Blanc During 1988-1991: Relation To Δ 18o-Deduced Sea-Surface Temperatures And Trade Winds, G. Fischer, B. Donner, V. Ratmeyer, R. Davenport, G. Wefer

Journal of Marine Research

Particle fluxes measured from 1988 to 1991 adjacent to a coastal upwelling site off Cape Blanc showed significant interannual variability of fluxes and sea-surface temperatures (SST) deduced from stable oxygen isotope analysis of the planktonic foraminifera Globigerinoides ruber and, partly, of the pteropod Limacina inflata. For the duration of the study period, a decrease in the seasonality of SST's was observed, as well as a significant decrease in the average annual SST from 24.4° to 20.8°C. This cooling trend was mainly the effect of a drastic decrease in the summer to fall SST (from 27.2° to 21.8°C). In comparison, …

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Molecular Diversity Of The Copepod, Nannocalunus Minor: Genetic Evidence Of Species And Population Structure In The North Atlantic Ocean, Anna Bucklin, Todd C. Lajeunesse, Eva Curry, John Wallinga, Karen Garrison

Journal of Marine Research

The abundant calanoid copepod, Nannocalanus minor, is widespread from the Florida Straits (FS), throughout the Gulf Stream and the Sargasso Sea, to the eastern North Atlantic Ocean. Does the species represent a single, randomly-mating population across this extensive region, or does it comprise a number of genetically distinct populations or taxonomically distinct forms? What are patterns and pathways of dispersal of the copepod across the North Atlantic? These questions were addressed using population genetic analysis of DNA sequence variation of a 440 base-pair region of the mitochondrial 16S rRNA gene. This analysis separated N. minor into two genetically distinct …

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A High Resolution Camera System (Parca) For Imaging Particles In The Ocean: System Design And Results From Profiles And A Three-Month Deployment, Volker Ratmeyer, Gerold Wefer

Journal of Marine Research

For direct optical measurement of abundance, concentration and size distribution of marine particles, a high-resolution camera system (ParCa) was designed to improve on similar systems used by Honjo et al. (1984), Asper (1987) and others. Imaging a probe volume of up to 37 1, smallest particles with diameters of 50 μm can be counted. The images provide information on particle size, shape and abundance either during profiling through the water column or while moored in a certain depth over time. Depth profiles were acquired between fall 1992 and late spring 1993 on R. V. Meteor cruises M22-1 and M23-3 …

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Carbon Cycling In Mesohaline Chesapeake Bay Sediments 2: Kinetics Of Particulate And Dissolved Organic Carbon Turnover, Eric E. Roden, Jon H. Tuttle

Journal of Marine Research

Temporal and depth variations in benthic carbon metabolism rates were examined in relation to particulate organic carbon (POC) deposition rates and particulate and dissolved organic carbon degradation kinetics in two sediments from the mesohaline region of Chesapeake Bay. The depth distribution of a single pool of metabolizable POC (MPOC) in mid-Bay sediments was estimated by curve-fitting of dry weight POC profiles (“1-G” approach). Estimated MPOC pools accounted for 3–4% of total POC content in the upper 10 cm of sediment. First-order MPOC decay constants of ≈10 yr⁻¹ during the warm season were estimated from the ratio of …

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The Role Of Turbulence In The Sedimentation Loss Of Pelagic Aggregates From The Mixed Layer, Javier Ruiz

Journal of Marine Research

A simple approach is presented to model the effect that turbulence has on the sedimentation loss of pelagic particles from the mixed layer. The approach consists in determining how turbulence affects their vertical distribution by splitting the solution of the advection-diffusion equation into two functions, one for the concentration of particles in the mixed layer and the other one reflecting the shape of the profile of particle concentration. The results of the paper indicate that the sedimentation flux is seriously underestimated if a uniform distribution of particles is assumed in the mixed layer when turbulence levels are low. A correction …

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Grid-Scale Instability Of Convective-Adjustment Schemes, Paola Cessi

Journal of Marine Research

Through a simple illustrative example, it is shown that instantaneous convective adjustment schemes, of the type used in general circulation models to parametrize nonhydrostatic convective processes, lead to the spontaneous emergence of the smallest resolved horizontal scale: the grid mode is unstable regardless of the strength of the horizontal diffusivity. Convective adjustment vertically mixes properties at each grid-point, irrespective of the horizontal distribution of such properties. Thus, horizontal spatial gradients are amplified by convective adjustment, as long as adjustment is faster than the horizontal diffusion (or advection) time between neighboring grid-points. In the example presented here, the grid-scale instability is …

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Spin-Down And The Dynamics Of Dense Pool Gyres In Shallow Seas, A. E. Hill

Journal of Marine Research

Isolated lenses or domes of dense (often cold) bottom water are found in many shelf seas and can be expected to induce significant baroclinic circulations. However, provided they have the correct thermal wind shear, many flow states can support a bottom dome structure, including: (a) an anticyclonically circulating dense dome overlain by a static surface layer or (b) cyclonic surface flow around a static dome. A one-dimensional, two-layer, quasi-geostrophic model is applied to a Gaussian vortex to argue that, on account of bottom friction in shelf seas, the bottom layer will spin down to rest over a time-scale of just …

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Fluid Flow And Suspended Particulates As Determinants Of Polychaete Feeding Behavior, Michael J. Bock, Douglas C. Miller

Journal of Marine Research

We examined the interactive effects of fluid flow, bed characteristics and suspended load on the feeding behavior of four species of marine polychaetes. Two species of obligate deposit feeders (Marenzelleria viridis and Ampharete parvidentata) and two species of palp-coiling facultative suspension feeders (Spiochaetopterus oculatus and Spio setosa) were exposed to flow and sediment-bed treatments that served to decouple fluid flow and particle flux. We employed low (no particle transport), medium (transport of flocs only) and high (transport of sand) flow speeds in factorial treatments of natural sediment, winnowed bed (flocs removed), armored bed (no sand transport …

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The Solubility Pump Of Carbon In The Subtropical Gyre Of The North Atlantic, Michael J. Follows, Richard G. Williams, John C. Marshall

Journal of Marine Research

The subduction of carbon is examined using abiotic models of the solubility pump in the subtropical gyre of the North Atlantic. The importance of the seasonal cycle of the mixed layer, and advection of carbon, is examined using sensitivity experiments with a Lagrangian model of the carbon system. The rate of subduction of carbon is found to be strongly influenced by the gradients in mixed-layer thickness over the gyre and, to a lesser extent, modified by the end of winter bias in the properties of subducted fluid. A seasonally-cycling geochemical model of the carbon system is then developed for the …

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Inertial Gyre Solutions From A Primitive Equation Ocean Model, Annalisa Griffa, Eric P. Chassignet, Victoria Coles, Donald B. Olson

Journal of Marine Research

A numerical exploration of inertial equilibrium states obtained with a primitive equation ocean model suggests that they can be described using statistical mechanics theory developed in the framework of quasi-geostrophy. The performance of the numerical model is first assessed with respect to the quasi-geostrophic model considering a series of experiments in the quasi-geostrophic range, in a closed basin with flat bottom and varying Rossby numbers. The results show that our model is consistent with the quasi-geostrophic model even in terms of dependence from boundary conditions and eddy viscosity values, and that the free surface contribution is negligible. As in the …

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Deducing Dynamic Properties From Simulated Hydrographic Data: Part I. Results From A Non-Eddy-Resolving Model, Huai-Min Zhang, Nelson G. Hogg

Journal of Marine Research

Inverse models are widely used in oceanography. However, their reliability remains an open question, as comparison of inverse model results with real values of ocean parameters is difficult due to insufficient knowledge of the latter. The feasibility of extracting the ocean general circulation, mixing rates, as well as air-sea heat and freshwater fluxes from hydrographic data is studied by applying an inverse model to the CME (Community Modeling Effort) results where both the physics and parameter values are known. The inverse model assumes approximate thermal wind balance and steady state conservation laws for mass, heat, and salt, assumptions satisfied by …

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The Classification And Structure Of Megafaunal Assemblages In The Venezuela Basin, Caribbean Sea, Kevin B. Briggs, Michael D. Richardson, David K. Young

Journal of Marine Research

Data from 23 benthic trawls collected from the Venezuela Basin (3411–5062 m water depth) indicate that megafauna are less abundant than in basins of similar depths in the Atlantic and are segregated by sedimentary province. Taxonomic assemblages, in terms of abundance and biomass, from three sites coincide with distinctions of sedimentary characteristics among the pelagic, hemipelagic and turbidite sedimentary provinces. Mollusks, decapods and fishes are most abundant in trawls collected from the pelagic and hemipelagic provinces and anemones and holothurians are most abundant in trawls collected from the turbidite province. Sponges dominate the biomass of fauna in trawls collected in …

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Analysis Of The North Atlantic Climatologies Using A Combined Ogcm/Adjoint Approach, Lisan Yu, Paola Malanotte-Rizzoli

Journal of Marine Research

An exact adjoint for the full-scale Bryan-Cox primitive equation model is applied to assimilate the North Atlantic climatologies. The inverse calculation aims at searching a steady state oceanic general circulation consistent with observations, by controlling the model input parameters (such as the initial states and the upper thermal and haline boundary conditions). Two climatological hydrographies (Levitus (1982) and Fukumori and Wunsch (1991)) are used for the assimilation. This enables the examination of the sensitivity of the assimilated results to data quality. In addition, the consistency between the climatological hydrography and fluxes is discussed by examining the fits between the optimally …

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An Experimental And Modeling Study Of Ph And Related Solutes In An Irrigated Anoxic Coastal Sediment, Roberta L. Marinelli, Bernard P. Boudreau

Journal of Marine Research

Macrofaunal irrigation is an important process in nearshore sediments, facilitating greater exchange between sediments and seawater and imparting significant lateral heterogeneity to the porewater profiles of many constituents. Like many macrofaunal activities, irrigation is a transient behavior, i.e. tubes and burrows are flushed periodically, at frequencies that generally are species-specific. As a result, transient concentrations within the dwelling arise, potentially impacting gradients, fluxes and reaction rates in the vicinity of the dwelling. We investigated the impact of periodic burrow irrigation on the distribution of several diagenetically important porewater constituents. Laboratory experiments evaluated irrigation periodicity using artificially irrigated tubes embedded in …

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Characterization Of The Particulate Protein In Pacific Surface Waters, Eiichiro Tanoue

Journal of Marine Research

The molecular characteristics of particulate protein in the surface waters along transects from 45N to 25S in the central Pacific are reported. The majority of particulate-combined amino acids (PCAA) was in the form of protein molecules in the samples from the northern North Pacific and Equatorial regions, namely, productive areas, while PCAA was mainly present as nonproteinaceous amino acid in the subtropical regions, namely, oligotrophic areas. Thus, it appears that the chemical form of PCAA, one of the major constituents of particulate organic matter (POM), varies meridionally. Two characteristic groups of particulate protein were identified from meridional differences in their …

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Variability And Sources Of The Southeastern Atlantic Circulation, Silvia L. Garzoli, Arnold L. Gordon, Vladimir Kamenkovich, Dale Pillsbury, Christopher Duncombe-Rae

Journal of Marine Research

The 1992–1993 Benguela Sources and Transport (BEST) time series provide a quantitative view of the Benguela Current transport and the eddy field crossing 30S, as well as an estimate of the relation between its barotropic and baroclinic components. This is done by a simultaneous analysis of the BEST data derived from inverted echo sounders, pressure sensors, current meter moorings, CTD, and ADCP stations. The analysis of the time series indicates that the annual mean baroclinic transport of the Benguela Current is 13 Sv with a total transport of 16 Sv. Through the combination of instruments the total baroclinic plus barotropic …

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Magnetic Resonance Imaging Of The Ovary : Can It Predict Low Response To Empiric Superovulation?, Rebecca Jane Crichton

Yale Medicine Thesis Digital Library

No abstract provided.

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The Value Of Lateral Chest Radiographs In The Assessment Of Bone Density And Detection Of Osteopenia, Monica Anna Medynski

Yale Medicine Thesis Digital Library

No abstract provided.

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Analysis Of In Vivo Tissue Expander Fluid Composition, Richard A. Nahouraii

Yale Medicine Thesis Digital Library

No abstract provided.

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The Effects Of Seagrass Patch Size And Energy Regime On Growth Of A Suspension-Feeding Bivalve, E. A. Irlandi

Journal of Marine Research

An investigation of how the presence of seagrass and seagrass patch size in high- and low-energy environments affected growth of an infaunal bivalve (hard clam, Mercenaria mercenaria) was carried out. Two general size classes of clams were used, mean length ca. 40.0 mm (41.9 mm) and mean length ca. 20.0 mm (22.3 mm and 19.0 mm), to see if growth responses were the same for large- and small-sized clams. Seagrass density, length and species composition as well as sediment characteristics were measured at high- and low-energy sites to determine if changes in seagrass and/or sediment dynamics could explain observed …

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Biogenic Matter Diagenesis On The Sea Floor: A Comparison Between Two Continental Margin Transects, William M. Berelson, Jim Mcmanus, Kenneth H. Coale, Kenneth S. Johnson, Tammy Kilgore, David Burdige, Cynthia Pilskaln

Journal of Marine Research

Benthic chamber measurements of the reactants and products involved with biogenic matter diagenesis (oxygen, ammonium, nitrate, silicate, phosphate, TCO₂, alkalinity) were used to define fluxes of these solutes into and out of the sediments off southern and central California. Onshore to offshore transects indicate many similarities in benthic fluxes between these regions. The pattern of benthic organic carbon oxidation as a function of water depth, combined with published sediment trap records, suggest that the supply of organic carbon from vertical rain can just meet the sedimentary carbon oxidation + burial demand for the central California region between the …

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Size-Dependent, Small-Scale Dispersion Of The Capitellid Polychaete, Mediomastus Ambiseta, Jeffrey Ellis Hughes

Journal of Marine Research

Small(≈cm)-scale spatial pattern of an abundant capitellid polychaete, Mediomastus ambiseta Hartman, was investigated in sediments of central Narragansett Bay, Rhode Island, USA from fall 1988 through spring 1992. Spatial autocorrelation techniques revealed a trend of decreasing patchiness and intensity of aggregation with increasing body size of M. ambiseta during the primary period of settlement and population growth (late summer-fall). The distribution and quality of particulate organic matter may explain the observed size-dependent spatial pattern. M. ambiseta influenced the small-scale distribution and concentration of organic matter and bacteria in surficial sediment. Experiments and field studies showed that this species creates two …

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Sedimentation Of Phytoplankton During A Diatom Bloom: Rates And Mechanisms, Thomas Kiorboe, Jorgen L. S. Hansen, Alice L. Alldredge, George A. Jackson, Uta Passow, Hans G. Dam, David T. Drapeau, Anya Waite, Carlos M. Garcia

Journal of Marine Research

Phytoplankton blooms are uncoupled from grazing and are normally terminated by sedimentation. There are several potential mechanisms by which phytoplankton cells may settle out of the photic zone: sinking of individual cells or chains, coagulation of cells into aggregates with high settling velocities, settling of cells attached to marine snow aggregates formed from discarded larvacean houses or pteropod feeding webs, and packaging of cells into rapidly falling zooplankton fecal pellets. We quantified the relative significance of these different mechanisms during a diatom bloom in a temperate fjord, and evaluated their potential to control phytoplankton population dynamics. Overall specific sedimentation rates …

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Spatial Variation In Short-Term (234th) Sediment Bioturbation Intensity Along An Organic-Carbon Gradient, Robert A. Wheatcroft, William R. Martin

Journal of Marine Research

Natural and human-induced spatial gradients provide a useful vehicle with which to better understand diverse marine processes. On the Palos Verdes margin (S. California), historical and ongoing waste-water discharge has created an along-shelf gradient in organic C and total N, as well as various trace metals and other pollutants (e.g., DDT). To better understand the impact of such pollution on bioturbation and to develop a more general understanding of the controlling factors of sediment bioturbation intensity, a series of stations representing severely, moderately and negligibly impacted sediments was studied. Vertical profiles of the naturally occurring radionuclide, ²³⁴Th, as well …

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Development Of An In-Vitro Technique To Study Vibration-Induced Spinal Injury, Timothy S. Johnson

Yale Medicine Thesis Digital Library

No abstract provided.

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Targeting Of Calcitonin Gene-Related Peptide Expression To The Pancreatic Beta Cells Prevents Insulin-Dependent Diabetes Mellitus In Non-Obese Diabetic Mice, Armen Khachatryan

Yale Medicine Thesis Digital Library

No abstract provided.

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The Flow Field Off Southwest India At 8n During The Southwest Monsoon Of August 1993, Lothar Stramma, Jürgen Fischer, Friedrich Schott

Journal of Marine Research

The flow field off the southwest coast of India at 8N was investigated during RV Sonne cruise 89 in August 1993 by direct velocity observations from shipboard- and lowered-ADCP and geostrophic computations from CTD stations. The upper ocean between 75E and 76°52′E near the South Indian shelf was governed by a northward flow with a subsurface velocity maximum of 25 cm s⁻¹ at about 100 m depth. This flow, organized as a poleward undercurrent hugging the continental slope, is typical for the southwest monsoon season. The northward transport in August 1993 was 4.7 Sv (1 Sverdrup = 10^{6 …}

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Death Due To Injury In Quito, Equador, Eric Sean Steenlage

Yale Medicine Thesis Digital Library

No abstract provided.

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Full-Text Articles in Entire DC Network

The Private Demand For Information And The Effects Of Public Testing Programs: The Case Of Hiv, Michael Boozer, Tomas Philipson

Discussion Papers

Minute Of The Federal Open Market Committee Meeting - January 20-31, 1996, Federal Reserve System: Board Of Governors

Documents

Distinct Year-To-Year Particle Flux Variations Off Cape Blanc During 1988-1991: Relation To Δ 18o-Deduced Sea-Surface Temperatures And Trade Winds, G. Fischer, B. Donner, V. Ratmeyer, R. Davenport, G. Wefer

Journal of Marine Research

Molecular Diversity Of The Copepod, Nannocalunus Minor: Genetic Evidence Of Species And Population Structure In The North Atlantic Ocean, Anna Bucklin, Todd C. Lajeunesse, Eva Curry, John Wallinga, Karen Garrison

Journal of Marine Research

A High Resolution Camera System (Parca) For Imaging Particles In The Ocean: System Design And Results From Profiles And A Three-Month Deployment, Volker Ratmeyer, Gerold Wefer

Journal of Marine Research

Carbon Cycling In Mesohaline Chesapeake Bay Sediments 2: Kinetics Of Particulate And Dissolved Organic Carbon Turnover, Eric E. Roden, Jon H. Tuttle

Journal of Marine Research

The Role Of Turbulence In The Sedimentation Loss Of Pelagic Aggregates From The Mixed Layer, Javier Ruiz

Journal of Marine Research

Grid-Scale Instability Of Convective-Adjustment Schemes, Paola Cessi

Journal of Marine Research

Spin-Down And The Dynamics Of Dense Pool Gyres In Shallow Seas, A. E. Hill

Journal of Marine Research

Fluid Flow And Suspended Particulates As Determinants Of Polychaete Feeding Behavior, Michael J. Bock, Douglas C. Miller

Journal of Marine Research

The Solubility Pump Of Carbon In The Subtropical Gyre Of The North Atlantic, Michael J. Follows, Richard G. Williams, John C. Marshall

Journal of Marine Research

Inertial Gyre Solutions From A Primitive Equation Ocean Model, Annalisa Griffa, Eric P. Chassignet, Victoria Coles, Donald B. Olson

Journal of Marine Research

Deducing Dynamic Properties From Simulated Hydrographic Data: Part I. Results From A Non-Eddy-Resolving Model, Huai-Min Zhang, Nelson G. Hogg

Journal of Marine Research

The Classification And Structure Of Megafaunal Assemblages In The Venezuela Basin, Caribbean Sea, Kevin B. Briggs, Michael D. Richardson, David K. Young

Journal of Marine Research

Analysis Of The North Atlantic Climatologies Using A Combined Ogcm/Adjoint Approach, Lisan Yu, Paola Malanotte-Rizzoli

Journal of Marine Research

An Experimental And Modeling Study Of Ph And Related Solutes In An Irrigated Anoxic Coastal Sediment, Roberta L. Marinelli, Bernard P. Boudreau

Journal of Marine Research

Characterization Of The Particulate Protein In Pacific Surface Waters, Eiichiro Tanoue

Journal of Marine Research

Variability And Sources Of The Southeastern Atlantic Circulation, Silvia L. Garzoli, Arnold L. Gordon, Vladimir Kamenkovich, Dale Pillsbury, Christopher Duncombe-Rae

Journal of Marine Research

Magnetic Resonance Imaging Of The Ovary : Can It Predict Low Response To Empiric Superovulation?, Rebecca Jane Crichton

Yale Medicine Thesis Digital Library

The Value Of Lateral Chest Radiographs In The Assessment Of Bone Density And Detection Of Osteopenia, Monica Anna Medynski

Yale Medicine Thesis Digital Library

Analysis Of In Vivo Tissue Expander Fluid Composition, Richard A. Nahouraii

Yale Medicine Thesis Digital Library

The Effects Of Seagrass Patch Size And Energy Regime On Growth Of A Suspension-Feeding Bivalve, E. A. Irlandi

Journal of Marine Research

Biogenic Matter Diagenesis On The Sea Floor: A Comparison Between Two Continental Margin Transects, William M. Berelson, Jim Mcmanus, Kenneth H. Coale, Kenneth S. Johnson, Tammy Kilgore, David Burdige, Cynthia Pilskaln

Journal of Marine Research

Size-Dependent, Small-Scale Dispersion Of The Capitellid Polychaete, Mediomastus Ambiseta, Jeffrey Ellis Hughes

Journal of Marine Research

Sedimentation Of Phytoplankton During A Diatom Bloom: Rates And Mechanisms, Thomas Kiorboe, Jorgen L. S. Hansen, Alice L. Alldredge, George A. Jackson, Uta Passow, Hans G. Dam, David T. Drapeau, Anya Waite, Carlos M. Garcia

Journal of Marine Research

Spatial Variation In Short-Term (234th) Sediment Bioturbation Intensity Along An Organic-Carbon Gradient, Robert A. Wheatcroft, William R. Martin

Journal of Marine Research

Development Of An In-Vitro Technique To Study Vibration-Induced Spinal Injury, Timothy S. Johnson

Yale Medicine Thesis Digital Library

Targeting Of Calcitonin Gene-Related Peptide Expression To The Pancreatic Beta Cells Prevents Insulin-Dependent Diabetes Mellitus In Non-Obese Diabetic Mice, Armen Khachatryan

Yale Medicine Thesis Digital Library

The Flow Field Off Southwest India At 8n During The Southwest Monsoon Of August 1993, Lothar Stramma, Jürgen Fischer, Friedrich Schott

Journal of Marine Research

Death Due To Injury In Quito, Equador, Eric Sean Steenlage

Yale Medicine Thesis Digital Library