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Similar Rapid Response To Phytodetritus Deposition In Shallow And Deep-Sea Sediments, L. Moodley, J. J. Middelburg, K. Soetaert, H. T. S. Boschker, P. M. J. Herman, C. H. R. Heip Jan 2005

Similar Rapid Response To Phytodetritus Deposition In Shallow And Deep-Sea Sediments, L. Moodley, J. J. Middelburg, K. Soetaert, H. T. S. Boschker, P. M. J. Herman, C. H. R. Heip

Journal of Marine Research

The short-term benthic response to an input of fresh organic matter was examined in vastly contrasting benthic environments (estuarine intertidal to deep-sea) using 13C-labeled diatoms as a tracer of labile carbon. Benthic processing was assessed in major compartments through 13C-enrichment in σCO2, in bacteria-specific phospholipids and in fauna tissue. A rapid response was evident in all environments. Under warm bottom water (14–18°C), similar quantities of the added carbon were respired within 24 hours in shallow and deep-sea sediments. However, the speed and magnitude of respiration were strongly reduced under low bottom water temperature (4–6°C), both in …

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On Rectification Of Randomly Forced Flows, Pavel S. Berloff Jan 2005

On Rectification Of Randomly Forced Flows, Pavel S. Berloff

Journal of Marine Research

Nonlinear rectification of the ocean circulation driven by random forcing, which simulates the effect of unresolved eddies, is studied in an idealized closed basin. The results are based on the analysis of randomly forced solutions and linear eigenmodes. Depending on the forcing strength, two rectification regimes are found: zonal jets and isolated gyres. It is shown that both regimes are due to nonlinear interactions of resonant basin modes. In the zonal-jet regime, these interactions involve complex interplay between resonant baroclinic modes and some secondary modes. Both Rhines' scaling for zonal jets and prediction of gyres based on the maximum entropy …

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Dynamics Of A Co2-Seawater Interface In The Deep Ocean, Joakim Hove, Peter M. Haugan Jan 2005

Dynamics Of A Co2-Seawater Interface In The Deep Ocean, Joakim Hove, Peter M. Haugan

Journal of Marine Research

A trough filled with liquid CO2 located at 3940 m depth has been used as a model system for CO2 deposition on the seafloor. To study the intrinsic properties of the interface between CO2 and seawater a wave maker was used to excite regular plane waves. The frequency (≲2.5 rad/s) and wavelength (20 cm–40 cm) of the waves have been measured, and compare reasonably well with the dispersion relation for deep fluid gravity waves. The shear stability of the interface was investigated by setting the water above the CO2 in motion with a thruster. For shear …

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Solute-Specific Pore Water Irrigation: Implications For Chemical Cycling In Early Diagenesis, Christof Meile, Peter Berg, Philippe Van Cappellen, Kagan Tuncay Jan 2005

Solute-Specific Pore Water Irrigation: Implications For Chemical Cycling In Early Diagenesis, Christof Meile, Peter Berg, Philippe Van Cappellen, Kagan Tuncay

Journal of Marine Research

In one-dimensional (1D) early diagenetic models, bioirrigation is typically represented by a nonlocal mass transfer or bioirrigation coefficient, α. Usually, all pore water species are assigned the same α. Here, we show that this assumption can lead to significant errors in estimates of bioirrigation intensities. Using a simplified early diagenetic reaction network, we compute the 3D concentration fields of major pore water species around a vertical burrow, as well as the solute fluxes across the burrow wall. From these results, corresponding 1D vertical α profiles are derived. The α profiles show pronounced differences from one solute to another. Dissolved O …

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Recent Interannual Upper Ocean Variability In The Deep Southeastern Bering Sea, Amy E. Wirts, Gregory C. Johnson Jan 2005

Recent Interannual Upper Ocean Variability In The Deep Southeastern Bering Sea, Amy E. Wirts, Gregory C. Johnson

Journal of Marine Research

Recent seasonal and interannual variability of the upper ocean in the southeast Aleutian Basin of the Bering Sea is related to air sea fluxes, ocean advection, and mixing. Between the winter of 2001/2002 and that of 2002/2003 a warming and freshening of the upper ocean was observed in data from a regional array of profiling Conductivity-Temperature-Depth (CTD) floats. The mild winter of 2002/2003 resulted in an unusually warm, fresh, light, and shallow winter mixed layer and a weakly ventilated temperature minimum layer. These unusual winter conditions contributed to a substantial reduction in the subsurface temperature inversion characteristic of the southeast …

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Subantarctic Mode Water And Antarctic Intermediate Water In The South Indian Ocean Based On Profiling Float Data 2000 –2004, Annie P. S. Wong Jan 2005

Subantarctic Mode Water And Antarctic Intermediate Water In The South Indian Ocean Based On Profiling Float Data 2000 –2004, Annie P. S. Wong

Journal of Marine Research

Autonomous CTD profiling float data from Argo between 2000 and 2004 have been used to study the properties of Subantarctic Mode Water (SAMW) and Antarctic Intermediate Water (AAIW) in relation to local winter mixed layer properties and frontal regimes in the South Indian Ocean. By calculating noise variance at the tightest part of the -S curve, the accuracy of salinity in the selected Argo data set has been estimated to be better than 0.01 psu. The basin-wide and seasonally unbiased sampling of the float array shows that South Indian Ocean SAMW is more continuous in geographical and density space …

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Bering Strait Transports From Satellite Altimetry, J. Y. Cherniawsky, W. R. Crawford, O. P. Nikitin, E. C. Carmack Jan 2005

Bering Strait Transports From Satellite Altimetry, J. Y. Cherniawsky, W. R. Crawford, O. P. Nikitin, E. C. Carmack

Journal of Marine Research

TOPEX/POSEIDON altimetry data are used to compute sea level slopes across the Bering Strait and associated geostrophic transport anomalies through the strait during ice-free periods from 1992 to 2002. The satellite turning latitude near 66N is just north of the strait, allowing us to use data from seven nearly zonal altimeter tracks close to the strait and to provide estimates of mean slopes, geostrophic currents and water transports approximately every 1.5 days. The altimeter-derived transport anomalies far exceed the mean value and are in good agreement with those derived from in situ observations. Comparison to wind data from a nearby …

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Diffusion Of Organic And Inorganic Solutes Through Macrofaunal Mucus Secretions And Tube Linings In Marine Sediments, Angelos K. Hannides, Shannon M. Dunn, Robert C. Aller Jan 2005

Diffusion Of Organic And Inorganic Solutes Through Macrofaunal Mucus Secretions And Tube Linings In Marine Sediments, Angelos K. Hannides, Shannon M. Dunn, Robert C. Aller

Journal of Marine Research

Transport models in sediments commonly assume that diffusion occurs through water saturated pore space and that diffusive properties are largely homogeneous and isotropic. The bioturbated zone of marine sediments is characterized by sediment pores filled with mucus gel and criss-crossed by organic membranes that line macrofaunal tubes and burrows. Diffusion experiments utilizing pedal mucus from the naticid snails, Neverita (=Polinices) duplicata and Euspira (=Lunatia) heros, and organic tube linings from the polychaetes Onuphis jenneri, Diopatra cupria, and Chaetopterus variopedatus, demonstrated that the diffusion of both organic and inorganic solutes is inhibited by …

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Change Of Sea Level Trend In The Mediterranean And Black Seas, I. Vigo, D. Garcia, B. F. Chao Jan 2005

Change Of Sea Level Trend In The Mediterranean And Black Seas, I. Vigo, D. Garcia, B. F. Chao

Journal of Marine Research

Sea level anomaly (SLA) data in the Mediterranean and Black seas obtained by ocean radar altimetry missions (TOPEX/Poseidon, Jason, ERS-1/2 and ENVISAT) are studied in conjunction with corresponding sea-surface temperature (SST) data. The studied time span is 11 years long, 1993-2003. Besides confirming previously published results, we report a significant, but enigmatic, abrupt change in the SLA trend that took place in mid-1999 which has been corroborated by independent tide gauge data. Results obtained from an Empirical Orthogonal Function (EOF) analysis show that the change in 1999 is not uniform in the Mediterranean Sea, which can thus be divided into …

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Energetics Of Wind-Driven Barotropic Variability In The Southern Ocean, Wilbert Weijer, Sarah T. Gille Jan 2005

Energetics Of Wind-Driven Barotropic Variability In The Southern Ocean, Wilbert Weijer, Sarah T. Gille

Journal of Marine Research

This study addresses the energetics of the Southern Ocean, in response to high-frequency wind forcing. A constant-density, multi-layer model is forced with a band of stochastically varying wind stress. The focus is on the interplay between the surface layer and the interior circulation.In line with previous examinations, it is concluded that the interior ocean is not directly energized by the wind work, but rather through the work done by the pressure field. The spatial and temporal characteristics of these terms differ substantially. Although the wind work may be negative in extensive regions of the World Ocean, the pressure work energizes …

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Frb Summary Of Supervisory Activity And Findings On Citi, Dianne Dobbeck, Federal Reserve System: Board Of Governors Jan 2005

Frb Summary Of Supervisory Activity And Findings On Citi, Dianne Dobbeck, Federal Reserve System: Board Of Governors

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The provided summary is preceded by a letter from Dianne Dobbeck summarizing its findings.

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Gene Discovery In Developmental Neuropsychiatric Disorders : Clues From Chromosomal Rearrangements, Thomas V. Fernandez Jan 2005

Gene Discovery In Developmental Neuropsychiatric Disorders : Clues From Chromosomal Rearrangements, Thomas V. Fernandez

Yale Medicine Thesis Digital Library

No abstract provided.

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Assessment Of Endothelial Cell Dysfunction In Pregnant Women With Either Preeclampsia Or Preexisting Vascular Disease By Brachial Artery Ultrasound, Inna V. Landres Jan 2005

Assessment Of Endothelial Cell Dysfunction In Pregnant Women With Either Preeclampsia Or Preexisting Vascular Disease By Brachial Artery Ultrasound, Inna V. Landres

Yale Medicine Thesis Digital Library

No abstract provided.

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Recruitment Responses Of Benthic Infauna To Manipulated Sediment Geochemical Properties In Natural Flows, Steven J. Engstrom, Roberta L. Marinelli Jan 2005

Recruitment Responses Of Benthic Infauna To Manipulated Sediment Geochemical Properties In Natural Flows, Steven J. Engstrom, Roberta L. Marinelli

Journal of Marine Research

Recent studies have shown that local variation in surface sediment geochemistry can have significant effects on recruitment rates of benthic invertebrates. Experiments presented here tested (1) the utility of manipulating surface porewater concentrations using spiked polyacrylamide gels and (2) the recruitment responses of the polychaete Arenicola cristata and the bivalve Mercenaria mercenaria to manipulated ammonium concentrations in realistic flows provided by a straight flume and an annular flume. Data show that successful manipulation of sediment porewater ammonium concentration is feasible in flowing waters, i.e., overlying waters remained relatively free of ammonium while manipulated concentration levels were maintained within the upper …

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Mixing Within The Interior Of The Faeroe-Shetland Channel, Phil Hosegood, Hans Van Haren, Cornelis Veth Jan 2005

Mixing Within The Interior Of The Faeroe-Shetland Channel, Phil Hosegood, Hans Van Haren, Cornelis Veth

Journal of Marine Research

Observations of the distribution of the density field, the dissipation rate of turbulent kinetic energy, ε, the vertical diffusivity, Kz, and optical backscatter over a repeated cross-section of the Faeroe-Shetland Channel (FSC) are presented within the context of ocean mixing. Turbulence in the permanent pycnocline occurs in discrete vertical patches of thickness 20–50 m coincident with layers of elevated vertical current shear magnitude, |S| > 10−2 s−1. The layers of elevated shear result from high-wavenumber internal waves which may break through shear instabilities as indicated by critical Richardson numbers, Ri < 1. The internal waves are ubiquitous features of strong boundary currents flowing along continental shelves and are likely generated here by geostrophic adjustment of the pycnocline in response to lateral excursions of the boundary current over the Shetland slope or by the scattering of internal tide energy. The pycnocline as a whole exhibits Kz > 10−4.5 m2 …

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Statistical Inversion Of South Atlantic Circulation In An Abyssal Neutral Density Layer, Ian W. Mckeague, Geoff Nicholls, Kevin Speer, Radu Herbei Jan 2005

Statistical Inversion Of South Atlantic Circulation In An Abyssal Neutral Density Layer, Ian W. Mckeague, Geoff Nicholls, Kevin Speer, Radu Herbei

Journal of Marine Research

This paper introduces a Bayesian inversion approach to estimating steady state ocean circulation and tracer fields. It is based on a quasi-horizontal flow model and a PDE solver for the forward problem of computing solutions to the tracer field advection-diffusion equations. A typical feature of existing ocean circulation inverse methods is a preprocessing stage in which the tracer data are interpolated over a regular grid and the interpolation error is ignored in the subsequent inversion. Our approach only uses interpolated data at those grid points that have neighboring hydrographic stations. By exploiting physically-based models in an integrated fashion, the method …

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Lagrangian Spin Parameter And Coherent Structures From Trajectories Released In A High-Resolution Ocean Model, Milena Veneziani, Annalisa Griffa, Zulema D. Garraffo, Eric P. Chassignet Jan 2005

Lagrangian Spin Parameter And Coherent Structures From Trajectories Released In A High-Resolution Ocean Model, Milena Veneziani, Annalisa Griffa, Zulema D. Garraffo, Eric P. Chassignet

Journal of Marine Research

A study of the mesoscale eddy field in the presence of coherent vortices, by means of Lagrangian trajectories released in a high-resolution ocean model, is presented in this paper. The investigation confirms previous results drawn from real float data statistics (Veneziani et al., 2004) that the eddy field characteristics are due to the superposition of two distinct regimes associated with strong coherent vortices and with a typically more quiescent background eddy flow. The former gives rise to looping trajectories characterized by subdiffusivity properties due to the trapping effect of the vortices, while the latter produces nonlooping floats characterized by simple …

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Two Coastal Upwelling Domains In The Northern California Current System, Adriana Huyer, Jane H. Fleischbein, Julie Keister, P. Michael Kosro, Natalie Perlin, Robert L. Smith, Patricia A. Wheeler Jan 2005

Two Coastal Upwelling Domains In The Northern California Current System, Adriana Huyer, Jane H. Fleischbein, Julie Keister, P. Michael Kosro, Natalie Perlin, Robert L. Smith, Patricia A. Wheeler

Journal of Marine Research

A pair of hydrographic sections, one north and one south of Cape Blanco at 42.9N, was sampled in five summers (1998–2000 and 2002–2003). The NH line at 44.6N lies about 130 km south of the Columbia River, and spans a relatively wide shelf off Newport, Oregon. The CR line at 41.9N off Crescent City, California, lies 300 km farther south and spans a narrower shelf. Summer winds are predominantly southward in both locations but the southward winds are stronger on the CR line. Sampling included CTD/rosette casts (to measure temperature, salinity, dissolved oxygen, nutrients, chlorophyll), zooplankton net tows and continuous …

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Growth Rates Of Interface-Feeding Spionid Polychaetes In Simulated Tidal Currents, Brian T. Hentschel, Brenda S. Herrick Jan 2005

Growth Rates Of Interface-Feeding Spionid Polychaetes In Simulated Tidal Currents, Brian T. Hentschel, Brenda S. Herrick

Journal of Marine Research

Most spionid polychaetes switch from surface deposit feeding to suspension feeding as current speed and the flux of suspended food increase. Previous experiments testing the effects of flow on the growth of facultative, interface feeders have been limited to very simplified flow regimes such as constant, unidirectional currents. To measure the growth of interface-feeding spionids in more realistic currents, we programmed two identical counter-rotating annular flumes to simulate two different semidiurnal tidal currents. Each regime included four speeds that varied in hourly steps. At 5 mm above bottom, speeds in the slower flow regime were 0, 2.5, 5, and 7.5 …

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Parameterizations Of Lagrangian Spin Statistics And Particle Dispersion In The Presence Of Coherent Vortices, Milena Veneziani, Annalisa Griffa, Andy M. Reynolds, Zulema D. Garraffo, Eric P. Chassignet Jan 2005

Parameterizations Of Lagrangian Spin Statistics And Particle Dispersion In The Presence Of Coherent Vortices, Milena Veneziani, Annalisa Griffa, Andy M. Reynolds, Zulema D. Garraffo, Eric P. Chassignet

Journal of Marine Research

Coherent vortices are known to play an important role in transport processes of ideal flows such as two-dimensional and quasi-geostrophic turbulent flows. In this paper, their effect on eddy dispersion and diffusivity is studied in a realistic oceanic flow, using synthetic Lagrangian data simulated within a high-resolution ocean general circulation model in the Gulf Stream recirculation region. The possibility of using a Lagrangian Stochastic Model (LSM) with nonzero mean spin statistic, Ω, to parameterize the observed characteristics is considered. The probability distribution of the Ω parameter (which is representative of the looping behavior of trajectories embedded inside the coherent vortices) …

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The All-Atlantic Temperature-Salinity-Pressure Relation And Patched Potential Density, Roland A. De Szoeke, Scott R. Springer Jan 2005

The All-Atlantic Temperature-Salinity-Pressure Relation And Patched Potential Density, Roland A. De Szoeke, Scott R. Springer

Journal of Marine Research

The relation between temperature, salinity, and pressure in the Atlantic Ocean is examined. Most of the Atlantic resolves itself into three two-dimensional manifolds of three-dimensional thermodynamic space: a northern, more saline, branch, and a southern, fresher, branch, each quite independent of pressure, and between them a bridge, on which density is uniform at constant pressure. The properties of the branches are crucial to the construction of joint potential density surfaces, patched together at 1000 db intervals. By resolving more finely in pressure (illustrated with 200 db spacing), a finer system of patched potential density surfaces can be obtained, and indeed …

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Diffusion Scale Dependent Change In Anaerobic Carbon And Nitrogen Mineralization: True Effector Experimental Artifact?, Thomas Valdemarsen, Erik Kristensen Jan 2005

Diffusion Scale Dependent Change In Anaerobic Carbon And Nitrogen Mineralization: True Effector Experimental Artifact?, Thomas Valdemarsen, Erik Kristensen

Journal of Marine Research

Burrowing macrofauna is known to influence the diffusion properties and solute transport within sediments as well as promoting aerobic microbial processes. It has recently been argued that changes in diffusion scales also affect anaerobic microbial processes in sediments. We tested this contention on coastal sandy sediment using a widely employed sediment plug flux-incubation technique. Our results confirm that volume specific microbial carbon and nitrogen mineralization apparently are enhanced (6–15 and 3–9 times, respectively) in thin (1 mm) compared with thick (10 cm) sediment plugs incubated in anoxic seawater. However, differential accumulation of inhibiting substances among plug sizes cannot explain this …

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Pathogenesis Of Intracranial Aneurysms, Brian Vala Nahed Jan 2005

Pathogenesis Of Intracranial Aneurysms, Brian Vala Nahed

Yale Medicine Thesis Digital Library

Introduction: Intracranial aneurysms (IA) are a common neurological problem, the rupture of which frequently constitutes a catastrophic neurological event. While the pathogenesis is largely unknown, it is believed that both genetic and environmental factors work in concert to some degree within patients. Our goal was to take a comprehensive approach to understanding the pathogenesis of IA by identifying factors leading to the formation, growth and rupture of IA. Methods: Since 1994, we have recruited patients and families with IA into the Yale Brain Aneurysm Database. Information regarding aneurysm characteristics (size, location, number), patient characteristics (age, medical, and social history), and …

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Behavioral Economics And Institutional Innovation, Robert J. Shiller Jan 2005

Behavioral Economics And Institutional Innovation, Robert J. Shiller

Cowles Foundation Discussion Papers

Behavioral economics has played a fundamental role historically in innovation in economic institutions, even long before behavioral economics was recognized as a discipline. Examples from history, notably that of the invention of workers’ compensation, illustrate this point. Though scholarly discussion develops over decades, actual innovation tends to occur episodically, particularly at times of economic crisis. Fortunately, some of the major professional societies, the Verein für Sozialpolitik, the American Economic Association and their successors, have managed to keep a broad discourse going, involving a variety of research methods including some that may be described today as behavioral economics, thereby maintaining an …

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Policy Effects In The Post Boom U.S. Economy, Ray C. Fair Jan 2005

Policy Effects In The Post Boom U.S. Economy, Ray C. Fair

Cowles Foundation Discussion Papers

The paper analyzes the question why the U.S. economy in the 2000:4-2004:3 period was sluggish in light of the large expansionary fiscal and monetary policies that took place. The answer does not appear to be that there were large structural changes in the economy or systematic bad shocks. This paper tests for such changes and shocks, and the results are generally negative. Instead, the main culprits seem to be large negative effects from declines in the stock market and exports. Although not tested in this paper, some of the decline in exports may be the result of the stock market …

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The Demand For Information: More Heat Than Light, Jussi Keppo, Giuseppe Moscarini, Lones Smith Jan 2005

The Demand For Information: More Heat Than Light, Jussi Keppo, Giuseppe Moscarini, Lones Smith

Cowles Foundation Discussion Papers

This paper produces a comprehensive theory of the value of Bayesian information and its static demand. Our key insight is to assume ‘natural units’ corresponding to the sample size of conditionally i.i.d. signals – focusing on the smooth nearby model of the precision of an observation of a Brownian motion with uncertain drift. In a two state world, this produces the heat equation from physics, and leads to a tractable theory. We derive explicit formulas that harmonize the known small and large sample properties of information, and reveal some fundamental properties of demand: (a) Value ‘non-concavity’: The marginal value of …

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Uncoupling Protein 2 Expression And Its Association With Atherosclerotic Disease Severity, John Kiene Forrest Jan 2005

Uncoupling Protein 2 Expression And Its Association With Atherosclerotic Disease Severity, John Kiene Forrest

Yale Medicine Thesis Digital Library

No abstract provided.

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The Effects Of 0.08% Blood Alcohol Concentration Limits On Traffic Fatalities In 31 States And The District Of Columbia : A Multiple Time-Series Analysis, Matthew Daniel Streckert Jan 2005

The Effects Of 0.08% Blood Alcohol Concentration Limits On Traffic Fatalities In 31 States And The District Of Columbia : A Multiple Time-Series Analysis, Matthew Daniel Streckert

Yale Medicine Thesis Digital Library

No abstract provided.

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Improving Medical Observational Skills : Analyzing Fine Art In A Gallery Setting Versus A Workbook Simulation, Erin Margaret Mahony Jan 2005

Improving Medical Observational Skills : Analyzing Fine Art In A Gallery Setting Versus A Workbook Simulation, Erin Margaret Mahony

Yale Medicine Thesis Digital Library

No abstract provided.

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Crisis And Challenge: The Changing Role Of The Hongkong & Shanghai Bank, 1950-2000, Leo F. Goodstadt Jan 2005

Crisis And Challenge: The Changing Role Of The Hongkong & Shanghai Bank, 1950-2000, Leo F. Goodstadt

Documents

No abstract provided.

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