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Numerical solution of heat conduction problems with a change of phase
Full text linkNumerical solutions for the freezing of finite slabs, cylinders, and spheres initially above the fusion temperature subject to boundary conditions of the first, second, and third kind were obtained by utilizing the DuFort-Frankel finite-difference scheme. Illustrative calculations for the transient temperature field, freezing front location, heat flux at the wall, and times for complete freezing were presented for various values of the dimensionless parameters. The ranges of values for the dimensionless parameters for which solutions can be successfully obtained were determined. FORTRAN IV computer programs which can be used to obtain solutions for any conditions within these ranges have been made available. The computer programs were written in such a way as to be easily extended and/or modified to solve other freezing problems
Some asymptotic results for functional lineal regression
Full text linkWe study the asymptotic behavior of the slop estimator in functional linear
regression model with functional outputs. It turns out that expansions of
analytic functions of covariance operator is a valuable tool in the theory of functional data. It this dissertation we apply this tool to obtain an upper bound for the integrated squared error (ISE) of the functional regression estimator for
both random and fixed design. A lower bound is also discussed in this paper and obtained by van Trees inequality in the fixed design case. Our calculations are based on abstract Hilbert space, which generalizes the optimal rate provided in Hall and Horowitz (2007)
(Re)Considering the jump scare in four elements
Full text linkReferences to jump scares and startle responses in the horror film literature routinely demonstrate a certain psychologizing impulse. According to Martin (2019), the jump scare that often provokes a startle reflex (SR) in audiences is perhaps “(t)he most well-used auditory (and visual) device in horror film(s)” (p. 5). Colloquially, the term jump scare refers to a sudden visual intrusion from offscreen combined with a sudden auditory outburst that ultimately intends to shock, surprise, or otherwise frighten the audience. Jump scares can serve as potentially ideal, ecologically rich stimuli for experimental studies exploring such topics as the defense cascade, the induction of emotions like fear and disgust, and selective exposure to negative stimuli (Bradley et al., 2001; Oliver, 2003). And yet, Baird (2000) laments that, “not a few philosophers and psychologists have been content to relegate (the) startle to the category of dumb reflex, little more dynamic than a sneeze or a knee jerk” (p. 13). This assumption can also be seen in recent psychological analyses of horror films that relegate the jump scare to simple cause-and-effect (e.g., Hye-Knudsen et al., 2024; Nummenmaa, 2024).
Perhaps for this reason, the experimental literature to date tends to focus on individual motivations for viewing the horror genre, rather than on addressing questions surrounding the perceptual and cognitive mechanisms underlying jump scares and the SRs they elicit. Why, for example, do jump scares stimulate intense emotional responses in spite of the audience's awareness of the art form's inherent fictionality? Similarly, if psychophysiological studies primarily associate the SR with fear, anger, and disgust (Bradley et al., 1999), why do horror films continue to fill theaters? Put more simply, why do we like scary movies?
To address these questions, we propose four elements of the jump scare that make it an ideal theoretical paradigm for experimental research in the years ahea
Isolation of Tumor and Leukemia Cells from Liquid Biopsies using the Human Transferrin Receptor
Full text linkMicrofluidic technologies have gained popularity in many areas of research due to their low sample consumption, ease of fabrication, portability, cost effectiveness, and versatility. In the microfluidic realm, fluids exhibit phenomena that are not readily observed in the macroscopic realm. In biological applications, the ability to manipulate small sample volumes is advantageous as the sample may be limited in some instances. To date several microfluidic applications have been developed that can be used to isolate various analytes of interest including cell-free DNA, proteins, cells, and others biomarkers. Chapter I serves as a general introduction to microfluidics. Chapter II reviews current clinical and microfluidic approaches for screening and diagnosing cancer. Chapter III and Chapter IV describes technologies developed during the course of these doctoral studies that detect low target cell concentrations by minimizing sample preparation and optimizing capture parameters. Chapter V qualitatively compares the degree of cell loss in a flow cytometric analysis, as a comparison of a competing method.
Cancer is a condition where healthy cells acquire genetic mutations which cause them to proliferate indefinitely. These cells are usually immature and have a rapid rate of proliferation. They cannot perform the functions of healthy cells. A cancer patient ultimately dies because cancer cells use up space and resources, and healthy organs are unable to perform their functions. If detected earlier the prognosis for cancer is improved. Before a cancer begins to metastasize, cancer treatment can be localized. However, after the onset of metastasis more universal treatment methods should be applied and it becomes more difficult to control the spread.
In Chapter III the described method is used to minimize sample handling. Usually, erythrocytes need to be removed from a patient sample to be used in an analysis for cancer cell separation and detection. However, as explained in Chapter V, a significant amount of target cells can be removed during cell washing cycles. This could result in false positive errors if the target cells are washed away. Therefore, a lysis circuit was introduced to deplete erythrocytes. Subsequently, the sample enriched with leukocytes and HL-60 cells was directed into an affinity capture chip. The cell capture of this sample was compared with the capture of a sample processed by benchtop lysis to deplete erythrocytes (prelysed sample). The on-chip lysis circuit was able to achieve cell capture of no significant difference using only about 1/8th of the sample volume required for the prelysed sample. Further, the shear force in the lysis chip also did not affect the viability of the HL-60 cells.
In Chapter IV, we have used a 5-channel herringbone chip to capture MDA-MB-231 and PC-3 cells from liquid biopsies. The 5-channel chip was able to capture cancer cells from sample with a 0.1% spike. Affinity capture is affected by fluid shear. By creating 5 parallel channels the input sample flow rate at affinity surfaces could be controlled, therefore a larger sample could be analyzed per minute. This chip was also compatible with the lysis chip described in Chapter III.
Chapter V compares the number of cells that can be detected using flow cytometry before and after a direct blood culture. In this study we found that over 80% of the spiked MDA-MB-231 and Jurkat cells went undetected in a flow cytometric analysis. Following a blood culture, a significantly higher proportion of cancer cells could be detected using flow cytometry. Adherent MDA-MB-231 cells yielded almost a pure sample of target cells (99 +/- 1%), whereas suspended Jurkat culture was significantly more enriched than the initial sample. The difference between these two samples is due to the fact, that once cultured, medium of suspended cells cannot be removed and replenished without removing target cells. Adherent cells can be washed post culture
Architecture Library Reference Bibliography
Full text linkThe bibliography attached is related to Veeder’s research article, “Reimaging Reference and Permanent Reserve Collections: Dynamic Presentation and Pedagogical Foundations.” Physical titles held in the Architecture Library are listed as they appear upon the shelves, with the curriculum-based categories of the Huckabee College of Architecture undergraduate courses framing the sections. The ‘Architects’ and ‘TTU & Lubbock’ sections noted in the research are not listed here-within
Dual-impedance cardiography for the assessment of arterial stiffness: associations with blood pressure, cardiometabolic risk factors, and preclinical atherosclerosis in midlife adults
Full text linkPurpose: Pulse wave velocity (PWV) is a measure of arterial stiffness that reflects vascular ageing and predicts risk for cardiovascular disease. We developed a PWV measurement method that uses dual-impedance cardiography (d-ICG) to address limitations of other common methods (e.g. ultrasound, tonometry, etc.), as well as to enable PWV assessments across a broader range of populations. This pre-registered, cross-sectional study tested for the first time the extent to which d-ICG PWV associates with cardiometabolic risk factors (i.e. blood pressure and other metabolic syndrome components) and vascular markers of preclinical atherosclerosis (i.e. carotid-artery intima-media thickness [C-IMT] and plaque).
Methods: Participants were 366 healthy adults (aged 28–57; 63.4% female). In a subsample (N = 179), estimates of d-ICG PWV were compared for the first time against carotid-femoral PWV (cfPWV) measured by a Complior device.
Results: d-ICG PWV and cfPWV measures were comparably associated with age and blood pressure (r’s ≥ .28, p’s ≤ .001), and they exhibited moderate consistency (ICCs = 0.51 to 0.55, p’s < .001). Across all cardiometabolic risk factors and markers of preclinical atherosclerosis, there were no clinically meaningful differences in the average composite (Fisher’s Z-score) correlations with arterial stiffness measured by d-ICG and cfPWV based on Cohen’s q values (q’s = 0.042 to 0.097).
Conclusion: d-ICG PWV may be a low-cost, reliable, and alternative method for obtaining estimates of arterial stiffness that track with cardiometabolic risk factors and preclinical atherosclerosis.The research reported here was supported by the National Heart, Lung, and Blood Institute of the National Institutes of Health under grants [P01 HL040962 and R01 HL169990]. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health
From Touch to Technology: The Design and Educational Application of a Tactile Feedback Device for Piano Teaching
Full text linkIn traditional piano instruction, teachers often use physical touch to guide students. When lessons move to digital formats, that form of guidance disappears and instruction relies entirely on verbal and visual cues. Although various tactile technologies have attempted to replicate physical guidance in experimental or therapeutic contexts, they have not yet been tested in everyday piano teaching. This study introduces TacTone, a prototype wearable vibration device developed specifically for this study to deliver real-time tactile cues during piano lessons, and examines its impact on technical correction and teacher-to-student communication.
One adult beginner participated in six in-person lessons: three with TacTone alternating with three with no device. Post-lesson surveys, observational notes from videorecorded lessons, and a final interview were used to compare student and teacher responses across conditions. When the device was used, errors were corrected more quickly by the student and with less reliance on repeated verbal explanation from the teacher. The participant reported that vibration cues provided immediate clarity regarding which finger to adjust and when to act, and that the sensation of how to respond remained even after the cue had stopped.
These findings suggest that tactile cues can reinforce physical understanding in ways verbal cues alone cannot, supporting more efficient correction and sustained accuracy in execution. Despite its limited scale, this study offers initial suggestions that a wearable feedback device like TacTone can restore the role of touch in technology-mediated piano instruction by providing a direct and applicable form of feedback without disrupting the flow of instruction
Watch what you say (on Facebook): Testing the spiral of silence in the social media era
No full textThis dissertation deals with the application of the spiral of silence theory to the non-anonymous context of Facebook. The major purpose of this work was to test Metzger's (2009) claim that the spiral of silence theory may be applicable within certain social network sites. The tenability of the theory in this online environment is evaluated through two independent tests using three morally-based issues including abortion, gay marriage, and immigration. Each test examined the influence of psychological attributes, communication influences, and opinion congruency on different strategies for speaking out and remaining silent. Study 1 was conducted with a university-affiliated convenience sample of Facebook users. Results showed that willingness to self-censor, Facebook network size, online discussion network heterogeneity, and opinion congruency with friends and family exert the most influence on the spiral of silence phenomenon. Study 2 was conducted with a nationwide sample of adult Facebook users. Results demonstrated that willingness to self-censor, online discussion network heterogeneity, selective use of online media, and experiences within the Facebook network were powerful predictors. A test of issue differences found that the varying influence of opinion congruency is issue specific. Specifically, future opinion congruency was found to inhibit the spiral of silence when discussion concerned an emerging issue. Overall, the results of this dissertation support the original contentions of the theory and lend support for the inclusion of new variables reflective of the new media environment. Additionally, the spiral of silence phenomenon appears to exist within Facebook, giving tentative support to Metzger’s (2009) claim that the theory will find renewed arenas for application
Nurturing Green Hearts: The Relationship Between Connectedness to Nature, Well-Being, and Ecocentrism
Full text linkResearch has repeatedly shown that spending time in nature can provide mental and physical health benefits like stress and anxiety reduction. Building on such findings, our study attempts to demonstrate a cyclical human-nature relationship, arguing that high levels of connectedness and interconnectedness to nature promote higher levels of environmental concern and higher life satisfaction levels.
A total of 106 U.S college students ranging from ages 18-24 were recruited through flyers, listservs, and snowball sampling. Participants completed our anonymous questionnaire via Qualtrics. The survey is a combination of four well-established scales used in both psychology and environmental psychology research: the Connectedness to Nature Scale (CNS), the New Ecological Paradigm (NEP) Scale, the Satisfaction with Life Scale (SWLS) and the Inclusion of Nature in Self (INS) Scale. These scales measure the four key variables in our study: belongingness to nature, environmental values, overall life satisfaction, and how much one chooses to include nature in one's life. In addition, we also gathered participants’ age, gender and major.
We hypothesized that participants with stronger connection and interconnectedness with nature will also exhibit higher levels of life satisfaction and environmental concern. Our data analysis proved higher levels of life satisfaction amongst participants that choose to include nature in their lives but no significant correlation between any other variables. Future research can focus on cultivating a connection with nature in the youth to possibly ensure consistent mental health benefits while also exploring the foundation of ecological responsibility within generations. Hence, the title of our study, Nurturing Green Hearts: The Relationship Between Connectedness to Nature, Well-Being, and Ecocentrism