Use of colour image analysis for assessment of fire damaged concrete

The aim of this project was to carry out a fundamental study to assess the potential of colour image analysis for use in investigations of fire damaged concrete. This involved:(a) Quantification (rather than purely visual assessment) of colour change as an indicator of the thermal history of concrete.(b) Quantification of the nature and intensity of crack development as an indication of the thermal history of concrete, supporting and in addition to, colour change observations.(c) Further understanding of changes in the physical and chemical properties of aggregate and mortar matrix after heating.(d) An indication of the relationship between cracking and non-destructive methods of testing e.g. UPV or Schmidt hammer. Results showed that colour image analysis could be used to quantify the colour changes found when concrete is heated. Development of red colour coincided with significant reduction in compressive strength. Such measurements may be used to determine the thermal history of concrete by providing information regarding the temperature distribution that existed at the height of a fire. The actual colours observed depended on the types of cement and aggregate that were used to make the concrete. With some aggregates it may be more appropriate to only analyse the mortar matrix. Petrographic techniques may also be used to determine the nature and density of cracks developing at elevated temperatures and values of crack density correlate well with measurements of residual compressive strength. Small differences in crack density were observed with different cements and aggregates, although good correlations were always found with the residual compressive strength. Taken together these two techniques can provide further useful information for the evaluation of fire damaged concrete. This is especially so since petrographic analysis can also provide information on the quality of the original concrete such as cement content and water / cement ratio. Concretes made with blended cements tended to produce small differences in physical and chemical properties compared to those made with unblended cements. There is some evidence to suggest that a coarsening of pore structure in blended cements may lead to onset of cracking at lower temperatures. The use of DTA/TGA was of little use in assessing the thermal history of concrete made with blended cements. Corner spalling and sloughing off, as observed in columns, was effectively reproduced in tests on small scale specimens and the crack distributions measured. Relationships between compressive strength/cracking and non-destructive methods of testing are discussed and an outline procedure for site investigations of fire damaged concrete is described

Protecting mental health in the Age of Anxiety: The context of Valium\u27s development, synthesis, and discovery in the United States, to 1963

This dissertation draws out various facets of the conditions preparing and situating Valium as a marketable substance and cultural entity. It offers one explanation for the widespread prescription and use of Valium in the 1960s. The post-World War II conceptualization of mental health and illness as a spectrum, with the majority of Americans falling between the poles and therefore either neurotic or at risk, heightened interest in mental health. Increased availability of health insurance brought more Americans to their physicians. National programs - establishment of the National Institutes of Mental Health, the Hill-Burton Act, and formation of a Joint Commission on Mental Illness and Health through the 1955 Mental Health Study Act - recognized widespread support for programs to increase the number of mental health practitioners and facilities focused on neuroses, personality disorders, and outpatients in general. Popular theories, including Walter Cannon\u27s homeostasis and Hans Selye\u27s General-Adaptation-Syndrome, promoted the idea that stress, and response to it, were among the most important aspects of health. The American public increased its demands for mental health services. Interplay between these conditions promoted use of psychopharmaceuticals. They were quick to prescribe and therefore allowed doctors to see more patients each day. They somaticized mental illness, bringing it within the boundaries of traditional medical insurance coverage. They did not cure an illness; they reduced symptoms and therefore either allowed the body to recover, or in an ongoing fashion prevented immature personalities from reaction to stresses in a manner leading to more serious medical problems. In the 1950s, it became possible to screen chemicals for a tranquilizer. The expense of creating and treating experimental neuroses in animals to screen chemical compounds was prohibitive. Yet these experiments informed pharmacologists; they could identify antineurotic or tranquilizing drugs through physical manifestations. With availability of antibiotics, pharmaceutical industries could keep fairly healthy populations of mice, rats, cats, and monkeys for testing. Chlorpromazine\u27s discovery and introduction into institutional psychiatry, around 1953, set out the basic features defining a tranquilizer. By 1958, pharmacologists had the ability and expectations required to inject a mouse with diazepam, check if it rolled off an inclined screen and, observing the tumbling rodent, recognize the ingested molecule was a potentially marketable tranquilizer. Valium\u27s development and discovery took place when tranquilizers were new and held out promise as mental health prophylactics, mild sedatives, and safe hypnotics. Mild mental illness needed rapid, effective, and fairly inexpensive treatment. Faced with patients undergoing severe or ongoing stress, doctors turned to anxiety-reducing drugs in order to prevent psychosomatic mechanisms resulting leading to any of a dozen physical illnesses. Compared with earlier alternatives - barbiturates, alcohol, major tranquilizers - Valium was safe, nonaddicting, and had few if any dangerous side effects

The microenvironment matters: estrogen deficiency fuels cancer bone metastases

Factors released during osteoclastic bone resorption enhance disseminated breast cancer cell progression by stimulating invasiveness, growth, and a bone-resorptive phenotype in cancer cells. Postmenopausal bone loss may accelerate progression of breast cancer growth in bone, explaining the anticancer benefit of the bone-specific antiresorptive agent zoledronic acid in the postmenopausal setting. Clin Cancer Res; 20(11); 2817-9. ©2014 AACR

Penning traps with unitary architecture for storage of highly charged ions

Penning traps are made extremely compact by embedding rare-earth permanent magnets in the electrode structure. Axially-oriented NdFeB magnets are used in unitary architectures that couple the electric and magnetic components into an integrated structure. We have constructed a two- magnet Penning trap with radial access to enable the use of laser or atomic beams, as well as the collection of light. An experimental apparatus equipped with ion optics is installed at the NIST electron beam ion trap (EBIT) facility, constrained to fit within 1 meter at the end of a horizontal beamline for transporting highly charged ions. Highly charged ions of neon and argon, extracted with initial energies up to 4000 eV per unit charge, are captured and stored to study the confinement properties of a one-magnet trap and a two-magnet trap. Design considerations and some test results are discussed

SU(3) Quantum Interferometry with single-photon input pulses

We develop a framework for solving the action of a three-channel passive optical interferometer on single-photon pulse inputs to each channel using SU(3) group-theoretic methods, which can be readily generalized to higher-order photon-coincidence experiments. We show that features of the coincidence plots vs relative time delays of photons yield information about permanents, immanants, and determinants of the interferometer SU(3) matrix

Identification of Walleye X Sauger Hybrid By Isozyme Electrophoresis

Of 125 phenotypic walleye screened by isozyme electrophoresis, one unusual individual was detected and subsequently suspected of being a walleye (Stizostedion vitreum vitreum) x sauger (S. canadense) hybrid. The isozyme pattern obtained for L-iditol dehydrogenase (IDDH, E.C. 1.1.1.14), phosphoglucomutase (PGM, E.C. 5.4.2.2) and a fast migrating aspartate aminotransferase (AAT, E.C. 2.6.1.1) isozyme showed that this individual had both walleye and sauger isozymes. Isozyme analyses is a useful technique for distinguishing walleye x sauger hybrids from parent species. This is the first report of alleles of the AAT* locus being species specific for sauger and walleye, and the first confirmed report of naturally occurring walleye x sauger hybrids in Minnesota

Generalized multi-photon quantum interference

Non-classical interference of photons lies at the heart of optical quantum information processing. This effect is exploited in universal quantum gates as well as in purpose-built quantum computers that solve the BosonSampling problem. Although non-classical interference is often associated with perfectly indistinguishable photons this only represents the degenerate case, hard to achieve under realistic experimental conditions. Here we exploit tunable distinguishability to reveal the full spectrum of multi-photon non-classical interference. This we investigate in theory and experiment by controlling the delay times of three photons injected into an integrated interferometric network. We derive the entire coincidence landscape and identify transition matrix immanants as ideally suited functions to describe the generalized case of input photons with arbitrary distinguishability. We introduce a compact description by utilizing a natural basis which decouples the input state from the interferometric network, thereby providing a useful tool for even larger photon numbers

Crossover from hydrodynamic to acoustic drag on quartz tuning forks in normal and superfluid 4He

We present measurements of the drag forces on quartz tuning forks oscillating at low velocities in normal and superfluid 4He. We have investigated the dissipative drag over a wide range of frequencies, from 6.5 to 600 kHz, by using arrays of forks with varying prong lengths and by exciting the forks in their fundamental and first overtone modes. At low frequencies the behavior is dominated by laminar hydrodynamic drag, governed by the fluid viscosity. At higher frequencies acoustic drag is dominant and is described well by a three-dimensional model of sound emission