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    Eye contact and intimacy

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    The meeting of the eyes is a potent form of communication. The eyes are able to convey many subtle nuances of feeling by their complex capacity for expression. Their stimulus configuration has made them highly noticeable; they serve as an innate releaser for the responses of animals and infants. The fact that they are critical in the maternal - infant relationship later gives them special meaning to the adult person. This is conveyed in the many references to the eyes found in literature, language, art, and mythology. Psychologists have begun to recognize, both in research and practice, the importance of eye contact in interpersonal interaction. Eyes intensify expressions of warmth and empathy, as well as hostility and aggression (Ellsworth & Carlsmith, 1968). Recognizing this, psycho- therapists have begun to emphasize the intimacy value of eye contact. Group therapists and sensitivity trainers often ask strangers to engage in eye contact as a way of transcending interpersonal barriers in a group. Many of the relationships between eye contact and variables such as sex, age, race, and culture have been investigated. It is assumed in most of these studies that eye contact leads to intimacy. The present study will attempt to document this assumption. For this purpose, it was hypothesized that 3 minutes of silent eye contact between a female subject and a confederate would facilitate inti- macy more so than the two selected silent control conditions which were also of 3 -minute duration. One of these involved looking at another part of the body, the hand, and the other was an interaction in which no instructions were given other than to maintain silence. For this study, intimacy was postulated to be composed of the Rogerian attitudes which facilitate therapeutic change - empathy, positive regard, and congruence. In addition to the main effect of condition, a secondary prediction involved a main effect of personality. That is, the way a subject responded to the confederate was partly related to the subject's style of relating to people, regardless of experimental condition. A three-way interaction effect was predicted for the dependent variable of state anxiety such that high AFFE would lead to an increase in anxiety going from high interpersonal contact- -the eye contact condition- -to low interpersonal contact- -the hand and non-directed conditions. The reverse was predicted for low AFFE. In addition, the magnitude of the interaction would differ for high vs. low anxious subjects on the trait anxiety. That is, the amount of anxiety experienced by high and low AFFE subjects in both the high and low contact conditions was hypothesized to be less. As predicted, in all cases women who made eye contact expressed more intimacy than the those with no eye contact. By their own report, they felt more empathy, positive feeling, and willingness to tell intimate details about their lives to the women they had visually contacted than did the women in the other situations. Furthermore, the hypothesis was partially confirmed that subjects who usually express affection to other people (high AFFE) feel greater empathy than do low AFFE subjects. Only in the case of empathy was the difference between high and low AFFE significant; however, the trend was in the predicted direction for self-disclosure and positive feeling variables. The final hypothesis was not supported. That is, trait anxiety did not interact significantly with condition and personality for state anxiety. Problems in the measurement of this variable may have accounted for the nonsignificant results. Implications for further research are discussed.This thesis was digitized as part of a project begun in 2014 to increase the number of Duke psychology theses available online. The digitization project was spearheaded by Ciara Healy

    The effects of attitude and commitment on retention

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    The literature pertaining to the effects of attitude on the learning and retention of controversial information was reviewed, and other variables which were thought to interact with attitude in its effect on memory were examined. No firm conclusions could be drawn because of the inconsistent results in past studies. The variable of commitment was singled out as a likely candidate for further study because of its possible crucial role in determining whether subjects would be open-minded in processing new information or whether they would react defensively to inconsistent material. Using Kiesler's (1971) work as a point of departure, it was hypothesized that the higher the subject's degree of commitment to a stand, the more difficult it would be for him to retain inconsistent information as compared to consistent material. Furthermore, it was expected that this effect would grow in strength as the retention interval increased in length. A final hypothesis predicted a positive correlation between the amount of inconsistent material retained and the degree of attitude change toward the position advocated in a counter -attitudinal speech. An attempt was made to develop new ways of examining more than just the quantity of a subject's recall. Accordingly, objective measures were developed of the types and amount of distortion present in recall and of the importance of the ideas recalled. The experimental design involved variation of three factors; degree of commitment (three levels), consistency of information with the subject's own position (two levels), and time of recall (two levels). Subjects were recruited from the Duke University subject pool, and a total of 120 subjects (10 per condition x 12 conditions) were used in the final analysis. Only subjects who indicated a stand definitely for or against capital punishment in a survey prior to the experiment were recruited. Commitment was manipulated by varying the public nature of a speech which subjects thought they would have to tape-record. Subjects in both the high and low commitment condition were given their choice of reading a speech either supporting or opposing capital punishment. Any subject who did not pick the side corresponding to his pre -measured attitude was dropped from the experiment. High commitment subjects thought that the tape recording would be made public and they would be identified as the speaker, while low commitment subjects thought that they would remain anonymous. A control condition, or no commitment condition, was created by offering some subjects the choice of reading one of two speeches unrelated to capital punishment. All subjects heard a speech either for or against capital punishment which was either consistent or inconsistent with their own beliefs on the issue ^ Half the subjects were tested for recall immediately after hearing the speech, and the other half were tested only after a delay of one week. Measures were also taken of subjects' recall ability, the degree of commitment they felt, and their attitude change. The results of the study showed that the commitment manipulation was executed successfully, but that none of the hypotheses were supported by the data. Higher degrees of commitment did not differentially affect subjects' recall of consistent and inconsistent information. Furthermore, the hypothesized positive relationship of attitude change to retention was rendered untenable because a significant correlation in the opposite direction was found. Two further hypotheses were developed to explain this negative correlation. A significant interaction between degree of commitment and time of recall was obtained for the amount of material recalled. This complex interaction was interpreted as the result of a combination of different anxiety levels and different amounts of rehearsal between conditions. Several small effects of dubious reliability involving the newly developed recall variables were found, but these findings need to be replicated because of the large number of significance tests conducted.This thesis was digitized as part of a project begun in 2014 to increase the number of Duke psychology theses available online. The digitization project was spearheaded by Ciara Healy

    Global Ottoman: The Cairo-Istanbul Axis

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    What does the Ottoman framework mean for urban historians of the Arab world and in particular of Egypt

    A phylogenetic transform enhances analysis of compositional microbiota data.

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    Surveys of microbial communities (microbiota), typically measured as relative abundance of species, have illustrated the importance of these communities in human health and disease. Yet, statistical artifacts commonly plague the analysis of relative abundance data. Here, we introduce the PhILR transform, which incorporates microbial evolutionary models with the isometric log-ratio transform to allow off-the-shelf statistical tools to be safely applied to microbiota surveys. We demonstrate that analyses of community-level structure can be applied to PhILR transformed data with performance on benchmarks rivaling or surpassing standard tools. Additionally, by decomposing distance in the PhILR transformed space, we identified neighboring clades that may have adapted to distinct human body sites. Decomposing variance revealed that covariation of bacterial clades within human body sites increases with phylogenetic relatedness. Together, these findings illustrate how the PhILR transform combines statistical and phylogenetic models to overcome compositional data challenges and enable evolutionary insights relevant to microbial communities

    Effects of age and curing on retrieval from semantic memory

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    Elderly subjects are known to perform less well than young subjects on laboratory tests of recall from episodic memory. Although the elderly report increased difficulty in recalling information from semantic memory, experimental attempts to demonstrate this deficit are equivocal. It is suggested that studies which use multiple choice tests to measure recall from semantic memory fail to find age-related deficits because the tests provide cues to aid in recall, a procedure known to reduce age-related differences in recall from episodic memory. When time to retrieve a single item of information from semantic memory is measured, some studies show an age-related deficit while others do not. When episodic recall is tested using categorized lists, the elderly show recall deficits largely because they access fewer categories than do young subjects. Semantic cues increase the number of categories recalled by the elderly subjects more than for young subjects in such tasks, Since studies with young subjects show that recall both from categorized lists and from a taxonomic category (a semantic recall task) proceeds via temporal clusters of related items, it was hypothesized that elderly subjects would show increased difficulty in accessing clusters of related items in a semantic recall task, just as they do in recall of categorized lists. Further, it was hypothesized that semantic cues would reduce the time taken by the elderly to access sequential clusters of information from semantic memory. In one experiment, healthy, well-educated young (ages 19-21) and old (ages 67-72) subjects were required to perform a Bousfield task: to generate examples from two taxonomic categories, foods and animals, for 15 minutes. The slope-difference algorithm, a procedure developed by Gruenewald and Lockhead, was used to categorize each subject's inter- item times (IIT's) into times between temporal clusters (BIIT's) and times between items within temporal clusters (WIIT). In a second experiment, a group of old subjects were given semantic differential labels as cues for recall on one of their two experimental trials. Results for the first experiment showed no age effect on mean BUT, number of clusters, or average cluster size for recall of food items. There were also no age effects during the first 5 minutes of recall of animals. Later in the task old subjects had longer mean BIIT's for animals than did young subjects. The differences appeared to result because old subjects tended to report primarily mammals, while young subjects reported birds, fish, reptiles/amphibians, and insects as well, A trend toward slower mean WIIT's for old subjects was attributed to slower vocalization rates. Thus, Experiment 1 failed to demonstrate age- related differences in time to access successive clusters of related items in semantic memory or in the rate at which items in a cluster are emitted. Higher repetition rates observed for the old subjects do support an age-related deficit in recognition. In the second experiment, only half the subjects reported that the semantic -differential cues were helpful in finding new items. No effect of cuing was observed for the food category. Cuing did significantly reduce mean BIIT for animals during the last 5 minutes of recall. However, the actual effect of cuing on number of clusters produced was minimal. It was suggested that more practice with the cues might have led to higher cue usage and a greater impact on BIIT.This thesis was digitized as part of a project begun in 2014 to increase the number of Duke psychology theses available online. The digitization project was spearheaded by Ciara Healy

    A Hybrid Global-local Numerical Method for Multiscale PDEs

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    We present a new hybrid numerical method for multiscale partial differential equations, which simultaneously captures both the global macroscopic information and resolves the local microscopic events. The convergence of the proposed method is proved for problems with bounded and measurable coefficient, while the rate of convergence is established for problems with rapidly oscillating periodic or almost-periodic coefficients. Numerical results are reported to show the efficiency and accuracy of the proposed method

    Molecular alterations in skeletal muscle in rheumatoid arthritis are related to disease activity, physical inactivity, and disability.

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    BACKGROUND: To identify molecular alterations in skeletal muscle in rheumatoid arthritis (RA) that may contribute to ongoing disability in RA. METHODS: Persons with seropositive or erosive RA (n = 51) and control subjects matched for age, gender, race, body mass index (BMI), and physical activity (n = 51) underwent assessment of disease activity, disability, pain, physical activity and thigh muscle biopsies. Muscle tissue was used for measurement of pro-inflammatory markers, transcriptomics, and comprehensive profiling of metabolic intermediates. Groups were compared using mixed models. Bivariate associations were assessed with Spearman correlation. RESULTS: Compared to controls, patients with RA had 75% greater muscle concentrations of IL-6 protein (p = 0.006). In patients with RA, muscle concentrations of inflammatory markers were positively associated (p < 0.05 for all) with disease activity (IL-1β, IL-8), disability (IL-1β, IL-6), pain (IL-1β, TNF-α, toll-like receptor (TLR)-4), and physical inactivity (IL-1β, IL-6). Muscle cytokines were not related to corresponding systemic cytokines. Prominent among the gene sets differentially expressed in muscles in RA versus controls were those involved in skeletal muscle repair processes and glycolytic metabolism. Metabolic profiling revealed 46% higher concentrations of pyruvate in muscle in RA (p < 0.05), and strong positive correlation between levels of amino acids involved in fibrosis (arginine, ornithine, proline, and glycine) and disability (p < 0.05). CONCLUSION: RA is accompanied by broad-ranging molecular alterations in skeletal muscle. Analysis of inflammatory markers, gene expression, and metabolic intermediates linked disease-related disruptions in muscle inflammatory signaling, remodeling, and metabolic programming to physical inactivity and disability. Thus, skeletal muscle dysfunction might contribute to a viscous cycle of RA disease activity, physical inactivity, and disability

    Assembly of hard spheres in a cylinder: a computational and experimental study

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    Hard spheres are an important benchmark of our understanding of natural and synthetic systems. In this work, colloidal experiments and Monte Carlo simulations examine the equilibrium and out-of-equilibrium assembly of hard spheres of diameter σ\sigma within cylinders of diameter σD2.82σ\sigma\leq D\leq 2.82\sigma. Although in such a system phase transitions formally do not exist, marked structural crossovers are observed. In simulations, we find that the resulting pressure-diameter structural diagram echoes the densest packing sequence obtained at infinite pressure in this range of DD. We also observe that the out-of-equilibrium self-assembly depends on the compression rate. Slow compression approximates equilibrium results, while fast compression can skip intermediate structures. Crossovers for which no continuous line-slip exists are found to be dynamically unfavorable, which is the source of this difference. Results from colloidal sedimentation experiments at high P\'eclet number are found to be consistent with the results of fast compressions, as long as appropriate boundary conditions are used. The similitude between compression and sedimentation results suggests that the assembly pathway does not here sensitively depend on the nature of the out-of-equilibrium dynamics

    Image noise and dose performance across a clinical population: patient size adaptation as a metric of CT performance.

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    PURPOSE: Modern CT systems adjust x-ray flux accommodating for patient size to achieve certain image noise values. The effectiveness of this adaptation is an important aspect of CT performance and should ideally be characterized in the context of real patient cases. The objective of this study was to characterize CT performance with a new metric that includes image noise and radiation dose across a clinical patient population. MATERIALS AND METHODS: The study included 1526 examinations performed by three CT scanners (one GE Healthcare Discovery CT750HD, one GE Healthcare Lightspeed VCT, and one Siemens SOMATOM definition Flash) used for two routine clinical protocols (abdominopelvic with contrast and chest without contrast). An institutional monitoring system recorded all the data involved in the study. The dose-patient size and noise-patient size dependencies were linearized by considering a first order approximation of analytical models that describe the relationship between ionization dose and patient size, as well as image noise and patient size. A 3D-fit was performed for each protocol and each scanner with a planar function, and the Root Mean Square Error (RMSE) values were estimated as a metric of CT adaptability across the patient population. RESULTS: The data show different scanner dependencies in terms of adaptability: the RMSE values for the three scanners are between 0.0385 HU(1/2) and 0.0215 HU(1/2) . CONCLUSIONS: A theoretical relationship between image noise, CTDIvol and patient size was determined based on real patient data. This relationship may be interpreted as a new metric related to the scanners' adaptability concerning image quality and radiation dose across a patient population. This method could be implemented to investigate the adaptability related to other image quality indexes and radiation dose in a clinical population. This article is protected by copyright. All rights reserved


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