Mid‐level intrusions at the continental shelf edge

Observations across the continental shelf offshore from New Jersey in late summer 1976 show an intrusion of saline water at the mid level of the water column across the shelf edge front, which appears in density only as an offshore thickening of the pycnocline. This internal density field produces horizontal pressure gradient forces within the pycnocline in the onshore direction. These forces, in the linearized equation of motion with a constant eddy viscosity, drive a circulation which resembles a double Ekman spiral for internal pressure vertical distributions which are thin with respect to the Ekman depth. For thick pressure distributions, the circulation is geostrophic. The resulting flow pattern has no net crossshelf transport. For the continental shelf edge in the example, a northward geostrophic mid-level jet is predicted by the theory. Ekman depth, and thus the vertical coefficient of eddy viscosity, can be determined from hydrographic data describing an intrusion

Computed tomography imaging to quantify iodine distribution in iododeoxyuridine-labeled DNA

Purpose: Treatment planning for x-ray activated Auger electron radiotherapy requires knowledge of the spatial distribution of Auger electron-producing target atoms in DNA; iodine is a candidate atom. Because planning uses computed tomography (CT) data to show anatomy, obtaining the target atoms\u27 distribution with CT methods is an attractive goal. This study evaluates the ability of two available CT systems to measure the target atoms\u27 spatial distribution. Method and Materials: A polychromatic desktop CT scanner and a synchrotron monochromatic CT system acquired images of iodine concentrations in water, ranging from 0.03-10 mg/ml. The polychromatic scanner was operated at 40 kVp while the synchrotron system was operated at 32.5 keV and 33.5 keV. Calibration curves of Hounsfield units (HU) vs. iodine concentration were obtained from each CT set, with minimum detectable iodine concentration defined as the smallest concentration distinguishable from water with contrast-to-noise ratio of 3. K-edge subtraction (KES) analysis was applied to the synchrotron CT data as another quantification method. To determine if iodine uptake could be quantified in vitro, Chinese hamster ovary (CHO) cells grown with iododeoxyuridine (IUdR) were imaged with the synchrotron. Iodine uptake was measured with the HU calibration curve and KES. Results: The expected iodine concentration for breast cancer in vivo is estimated to be 0.06 mg/ml for IUdR. The minimum detectable iodine concentration was 0.1 mg/ml for the 40 kVp polychromatic CT data and 0.1 mg/ml for the synchrotron CT at 33.5 keV; minimum detectability using KES was 0.25 mg/ml. Thus, these current systems could not visualize the estimated target concentration. The measured iodine concentration in the cells was 0.21±0.04 mg/ml using the HU calibration curve and 0.20±0.01 mg/ml using KES, compared to an expected concentration in DNA of 0.001 mg/ml. Conclusions: Using the current acquisition methods, these CT systems proved unable to measure the expected concentration. Improvements may be possible by modifying the acquisition parameters. From the cell image results, CT imaging for treatment planning will quantify both DNA-incorporated iodine and intracellular unincorporated iodine; if the two amounts can be shown to have a stable proportion; CT quantification methods may be satisfactory for treatment planning

On the calculation of wind stress curl over open ocean areas from synoptic meteorological data with application to time dependent ocean circulation

Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution January, 1972The method used by N. P. Fofonoff for estimating wind stress curl from surface atmospheric pressure maps is developed for use with the National Meterological Center analysis grid. A formula is developed relating the wind stress curl directly to geometrically apparent features of the surface pressure analyses. The sensitivity of the formula to small deviations in the basic pressure field is estimated. Some statistical properties of the resulting formula as applied to actual pressure analyses are investigated. In particular, the geostrophic wind estimated for two finite difference grids is compared to observed winds from an independent anemometer located at W.H.O.L site "D". The statistical distribution of wind stress curl estimates is found to be non-Gaussian. The difficulty in estimating a mean value from such distributions is discussed. The root mean square values of wind stress curl are found to be approximately 10 times the mean values. Means are estimated and found to be inadequate to drive the mean transports in the Gulf Stream and Kuroshio. The formula is applied at Bermuda and the results compared to the record from the tide gauge located there. A significant relation between wind stress curl and sea level is found after tidal and inverted barometer effects are suppressed. The formula is applied to time dependent motions of the Labrador Current as evidenced by iceberg drifts for the 1959 ice season. Agreement is found between calculated and observed iceberg motions on the eastern slope of the Grand Banks using static Sverdrup dynamics.Supported by the Office of Naval Research under Contract N00014-66-C0241; NR 083-004, and the U. S. Coast Guard contract DOT-CG- 10618-A

Forage Liberally: The Role of Agriculture in Sherman\u27s March to the Sea

This dissertation explores the intersection between Federal war policy and developments in Southern agriculture that created the environment for Major General William Tecumseh Sherman\u27s Savannah Campaign, better known as the March to the Sea, to take place. The first chapter describes the changes that took place in Georgia\u27s agriculture following secession that moved Southern farming from cash crop production to food staple cultivation. The second chapter illustrates the evolution of Northern military policies towards civilians that gave rise to the premise of hard war, especially in the use of foraging as a military weapon. Chapter three shows the planning process for the Savannah Campaign. Chapter four uses the accounts of Union soldiers to describe the agricultural environment they encountered along the path of the March to the Sea, and especially the actions of foragers against Confederate civilians on rural farms. The fifth chapter utilizes the accounts of Georgia\u27s plantation wives to show the impact of Sherman\u27s foragers on their farms and their lives. The conclusion offers final analysis of the question of Southern agriculture and Northern war policy, as well as aspects of Sherman\u27s March in the American memory

Solid rocket motor witness test

The Solid Rocket Motor Witness Test was undertaken to examine the potential for using thermal infrared imagery as a tool for monitoring static tests of solid rocket motors. The project consisted of several parts: data acquisition, data analysis, and interpretation. For data acquisition, thermal infrared data were obtained of the DM-9 test of the Space Shuttle Solid Rocket Motor on December 23, 1987, at Thiokol, Inc. test facility near Brigham City, Utah. The data analysis portion consisted of processing the video tapes of the test to produce values of temperature at representative test points on the rocket motor surface as the motor cooled down following the test. Interpretation included formulation of a numerical model and evaluation of some of the conditions of the motor which could be extracted from the data. These parameters included estimates of the insulation remaining following the tests and the thickness of the charred layer of insulation at the end of the test. Also visible was a temperature signature of the star grain pattern in the forward motor segment

Numerically Enhanced Thermal Inspection of Shuttle Solid Rocket Motor Inhibitor/Liner/Fuel Bondline

The Solid Rocket Motors (SRM’s) for the Space Shuttle are fabricated by laying up and molding materials, such as insulation, which are joined using adhesives, the adhesives being set along with the materials in a final curing process for an entire motor segment at a time. The resulting structure (Fig. 1) has two important properties from the point of view of inspection: integrity of the adhesive joints (bondlines) is of great importance, and the structure cannot be disassembled for inspection prior to use. Of particular interest are disbonds producing small voids (delaminations) at the bondlines. Specific delaminations can be located in service hardware only by using NDE methods. This paper reports on the application of thermal methods for performing such inspections

The design and investigation of nanocomposites containing dimeric nematogens and liquid crystal gold nanoparticles with plasmonic properties showing a nematic-nematic phase transition (Nᵤ-Nₓ/Ntb)

The construction of liquid crystal compositions consisting of the dimeric liquid crystal, CB_C9_CB (cyanobiphenyl dimer = 1",9"-bis(4-cyanobiphenyl-4'-yl)nonane), and the range of nematic systems is explored. The materials include a laterally functionalized monomer, which was used to construct a phase diagram with CB_C9_CB, as well as one laterally linked dimer liquid crystal material and two liquid crystal gold nanoparticle (LC-Au-NPs) systems. For the Au-NP-LCs, the NP diameters were varied between ~3.3 nm and 10 nm. Stable mixtures that exhibit a nematic-nematic phase transition are reported and were investigated by POM (polarizing optical microscopy), DSC (differential scanning calorimetry) and X-ray diffraction studies

Method of remotely characterizing thermal properties of a sample

A sample in a wind tunnel is radiated from a thermal energy source outside of the wind tunnel. A thermal imager system, also located outside of the wind tunnel, reads surface radiations from the sample as a function of time. The produced thermal images are characteristic of the heat transferred from the sample to the flow across the sample. In turn, the measured rates of heat loss of the sample are characteristic of the flow and the sample

Fine Scale Circulation Near Foxtrot in Hampton Roads, Virginia

During 1974 the Virginia Institute of Marine Science conducted a series of oceanographic, water quality and modeling studies for the outfall from the proposed Nansemond Wastewater Treatment Plant (VIMS, 1975). One of these studies included dye releases to determine the dispersion and transport of material discharged to Hampton Roads near Pig Point. These dye releases were made from the munitions loading piers known as Foxtrot . The proposed outfall, as given in the Facilities Plan is located roughly one kilometer to the east-south-east of Foxtrot. Tidal circulation in Hampton Roads is quite complex and there was concern that the distribution patterns for material released at the two sites would differ appreciably. Therefore a fine scale circulation study was conducted in the vicinity of Foxtrot