Nondestructive testing of concrete bridge decks using ground-penetrating radar and the chain drag method

This thesis presents the findings of two different nondestructive techniques that are used for bridge deck analysis: the chain drag method and ground penetrating radar (GPR). The chain drag testing was performed in the laboratory with 23 simulated concrete bridge deck specimens. The specimens contained varying internal conditions such as with/without steel reinforcement and with air and water filled cracks. The tests were to determine if the chains could uncover the different characteristics of each specimen, and to see if the varying sizes of the three chains had any influence on the outcome of the results.;The GPR testing was performed in the field on three highway bridge decks. The purpose of this testing was to determine if the GPR technique could accurately assess the depths to the different deck interfaces (overlay/concrete, 1st layer rebar, deck bottom, etc.), and to examine whether the radar software could find bridge deterioration

Cultural Influences in the Processing of Emotion Schemas Related to Death and Violence: A Pilot Study

Culture is a key element in determining emotions that people experience when facing death. Recent studies revealed a specific emotion schema for the affective response to death (in comparison with unpleasant/violence-related stimulus), influenced by differences in the personalities and learning processes of the individuals, on the one hand, and differences in the cultural and social contexts of the two groups, on the other. The objective of the research was to compare the English participants’ affective response to pictures of death to those of the Spanish participants, who viewed other types of affective pictures (pleasant, unpleasant/violence-related and neutral). A total of 38 young adults took part in an emotional assessment using a set of pictures from the International Affective Picture System (IAPS) database. They indicated the values of valence, arousal and dominance for each affective image. The results show that the images related to death were less unpleasant and caused a lower activation in the English population, while there were no differences in the two group’s responses to unpleasant/violent images

Carbon Nanotube Membranes for Use in the Transdermal Treatment of Nicotine Addiction and Opioid Withdrawal Symptoms

Transdermal systems are attractive methods of drug administration specifically when treating patients for drug addiction. Current systems however are deficient in therapies that allow variable flux values of drug, such as nicotine for smoking cessation or complex dosing regimens using clonidine when treating opioid withdrawal symptoms. Through the use of functionalized carbon nanotube (CNT) membranes, drug delivery to the skin can be controlled by applying a small electrical bias to create a programmable drug delivery system. Clearly, a transdermal patch system that can be tailored to an individual\u27s needs will increase patient compliance as well as provide much more efficient therapy. The purpose of this paper is to discuss the applicability of using carbon nanotube membranes in transdermal systems for treatment of drug abuse

The role of negative emotions in the social processes of entrepreneurship: Power rituals and shame-related appeasement behaviors

This paper examines the role of negative emotions in the social processes of entrepreneurship. Drawing on a study of Russian entrepreneurs, we develop a model of the emotional effects of social interactions between entrepreneurs and state officials. We found that negative emotions were elicited by these interactions and, in turn, fueled three forms of shame-related corrective appeasement behavior (reactive, anticipatory, and sporadic), which served to corrode entrepreneurial motivation and direct attention and energy away from business growth and development

Focal cerebral ischemia in the TNFalpha-transgenic rat

<p>Abstract</p> <p>Background</p> <p>To determine if chronic elevation of the inflammatory cytokine, tumor necrosis factor-α (TNFα), will affect infarct volume or cortical perfusion after focal cerebral ischemia.</p> <p>Methods</p> <p>Transgenic (TNFα-Tg) rats overexpressing the murine TNFα gene in brain were prepared by injection of mouse DNA into rat oocytes. Brain levels of TNFα mRNA and protein were measured and compared between TNFα-Tg and non-transgenic (non-Tg) littermates. Mean infarct volume was calculated 24 hours or 7 days after one hour of reversible middle cerebral artery occlusion (MCAO). Cortical perfusion was monitored by laser-Doppler flowmetry (LDF) during MCAO. Cortical vascular density was quantified by stereology. Post-ischemic cell death was assessed by immunohistochemistry and regional measurement of caspase-3 activity or DNA fragmentation. Unpaired <it>t </it>tests or analysis of variance with post hoc tests were used for comparison of group means.</p> <p>Results</p> <p>In TNFα-Tg rat brain, the aggregate mouse and rat TNFα mRNA level was fourfold higher than in non-Tg littermates and the corresponding TNFα protein level was increased fivefold (p ≤ 0.01). Infarct volume was greater in TNFα-Tg rats than in non-Tg controls at 24 hours (p ≤ 0.05) and 7 days (p ≤ 0.01). Within the first 10 minutes of MCAO, cortical perfusion measured by LDF was reduced in TNFα-Tg rats (p ≤ 0.05). However, regional vascular density was equivalent between TNFα-Tg and non-Tg animals (p = NS). Neural cellular apoptosis was increased in transgenic animals as shown by elevated caspase-3 activity (p ≤ 0.05) and DNA fragmentation (p ≤ 0.001) at 24 hours.</p> <p>Conclusion</p> <p>Chronic elevation of TNFα protein in brain increases susceptibility to ischemic injury but has no effect on vascular density. TNFα-Tg animals are more susceptible to apoptotic cell death after MCAO than are non-Tg animals. We conclude that the TNFα-Tg rat is a valuable new tool for the study of cytokine-mediated ischemic brain injury.</p

Measuring response functions of active materials from data

From flocks of birds to biomolecular assemblies, systems in which many individual components independently consume energy to perform mechanical work exhibit a wide array of striking behaviors. Methods to quantify the dynamics of these so called active systems generally aim to extract important length or time scales from experimental fields. Because such methods focus on extracting scalar values, they do not wring maximal information from experimental data. We introduce a method to overcome these limitations. We extend the framework of correlation functions by taking into account the internal headings of displacement fields. The functions we construct represent the material response to specific types of active perturbation within the system. Utilizing these response functions we query the material response of disparate active systems composed of actin filaments and myosin motors, from model fluids to living cells. We show we can extract critical length scales from the turbulent flows of an active nematic, anticipate contractility in an active gel, distinguish viscous from viscoelastic dissipation, and even differentiate modes of contractility in living cells. These examples underscore the vast utility of this method which measures response functions from experimental observations of complex active systems

BMQ

BMQ: Boston Medical Quarterly was published from 1950-1966 by the Boston University School of Medicine and the Massachusetts Memorial Hospitals. Pages 49-52, v17n2, provided courtesy of Howard Gotlieb Archival Research Center