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Memory and Production of Standard Frequencies in College-Level Musicians
This thesis examines the nature of long-term absolute pitch memoryâan ability traditionally assumed to belong only to absolute pitch (AP) possessorsâby testing for evidence of this memory for âstandardâ frequencies in musicians without AP. Standard frequencies, those based on the equally tempered system with A = 440 Hz, are common in the sonic environment of the Western college musical education, and thus could have the opportunity to penetrate listenersâ long-term memories. Through four experimental tasks, this thesis examines musiciansâ ability to recognize and produce frequencies from the set of equally tempered frequencies based on A = 440 Hz, without regard to those musiciansâ pitch-labeling abilities. The experimental tasks also compare freshmen with seniors to test if exposure to standard frequencies during a college musical education engrains standard frequencies in long-term memory. The results suggest that musicians without AP cannot distinguish between standard and nonstandard frequencies during listening tasks, but they may be able to recall them without prompting when singing familiar folk songs. However, musical training during the college years does not seem to improve these abilities. Further experimentation is needed to corroborate the results, including modifications to the current tasks and methodology, as well as a larger subject size
Effects of instagram sports posts on the athletic motivation of female elite athletes: Do they inspire or backfire?
The social networking site Instagram provides users with an abundance of photos and information in many domains including sports. The posts are often intended to inspire and motivate users. We argue that the display of success and failure of professional athletes may influence elite athletesâ own sports ambitions. Research has shown that exposure to positive ingroup stereotypes and exposure to negative outgroup stereotypes can increase performance (i.e., the stereotype boost effect and the stereotype lift effect, respectively). Based on this research, we conducted three experiments in two different cultural contexts. In all three experiments, we examined whether Instagram posts that showed either ingroup membersâ success or outgroup membersâ failure influenced athletic motivation, self-efficacy, and sports-related behavioral intentions of female elite athletes. Experiment 1 (n = 117) was conducted in Germany, whereas Experiments 2 (n = 137) and 3 (n = 143) were conducted in Norway. Results showed that in Germany, participantsâ athletic motivation and self-efficacy was highest when they were exposed to failing outgroup members (Exp. 1); however, this was not the case in Norway (Exp. 2). In contrast, only Norwegian participants who were exposed to successful ingroup members reported a significant increase in their athletic motivation, but there were no effects regarding self-efficacy and sports-related behavioral intentions (Exp. 3). Boundary conditions for Instagramâs role in motivating users and reasons for the differences between the two cultural contexts are discussed
Early Childhood Special Education in a Refugee Resettlement Community: Challenges and Innovative Practices
There has been a significant increase in the number of children who are culturally and linguistically diverse (CLD) who qualify for early childhood special education (ECSE) services (Banerjee & Guiberson, 2012). The current study investigates the challenges and innovative practices in the evaluation and (ECSE) services for preschool aged children who are refugees. Twenty-eight early childhood educators who work in a small refugee resettlement community participated in a qualitative study using semi-structured interviews resulting in themes regarding challenges and innovative practices. Challenges include: lack of validated assessments, wait time for evaluations, different cultural perspectives and family advocacy. Innovative practices include: assessing skills not dependent on language and including caregivers in evaluations. Implications for future research and teacher preparation are discussed
Contrast agents for molecular photoacoustic imaging.
Photoacoustic imaging (PAI) is an emerging tool that bridges the traditional depth limits of ballistic optical imaging and the resolution limits of diffuse optical imaging. Using the acoustic waves generated in response to the absorption of pulsed laser light, it provides noninvasive images of absorbed optical energy density at depths of several centimeters with a resolution of âŒ100 ÎŒm. This versatile and scalable imaging modality has now shown potential for molecular imaging, which enables visualization of biological processes with systemically introduced contrast agents. Understanding the relative merits of the vast range of contrast agents available, from small-molecule dyes to gold and carbon nanostructures to liposome encapsulations, is a considerable challenge. Here we critically review the physical, chemical and biochemical characteristics of the existing photoacoustic contrast agents, highlighting key applications and present challenges for molecular PAI.This work was supported by CRUK (Career Establishment Award no. C47594/A16267 to J.W. and S.E.B., Core Funding C14303/A17197 to J.W. and S.E.B.), the European Commission (CIG FP7-PEOPLE- 2013-CIG-630729 to J.W. and S.E.B.), the EPSRC-CRUK Cancer Imaging Centre in Cambridge and Manchester (C197/A16465 to J.W. and S.E.B.), Kingâs College London and University College London Comprehensive Cancer Imaging Centre Cancer Research UK & Engineering and Physical Sciences Research Council, in association with the Medical Research Council and the Department of Health, UK (P.B.), and the European Union (project FAMOS FP7 ICT, contract 317744 to P.B.).This is the author accepted manuscript. The final version is available from Nature Publishing Group via http://dx.doi.org/10.1038/nmeth.392
Peripheral halo-functionalization in [Cu(N^N)(P^P)]+ emitters: influence on the performances of light-emitting electrochemical cells
A series of heteroleptic [Cu(N^N)(P^P)][PF6] complexes is described in which P^P = bis(2-(diphenylphosphino)phenyl)ether (POP) or 4,5-bis(diphenylphosphino)-9,9-dimethylxanthene (xantphos) and N^N = 4,4âČ-diphenyl-6,6âČ-dimethyl-2,2âČ-bipyridine substituted in the 4-position of the phenyl groups with atom X (N^N = 1 has X = F, 2 has X = Cl, 3 has X = Br, 4 has X = I; the benchmark N^N ligand with X = H is 5). These complexes have been characterized by multinuclear NMR spectroscopy, mass spectrometry, elemental analyses and cyclic voltammetry; representative single crystal structures are also reported. The solution absorption spectra are characterized by high energy bands (arising from ligand-centred transitions) which are red-shifted on going from X = H to X = I, and a broad metal-to-ligand charge transfer band with λmax in the range 387â395 nm. The ten complexes are yellow emitters in solution and yellow or yellow-orange emitters in the solid-state. For a given N^N ligand, the solution photoluminescence (PL) spectra show no significant change on going from [Cu(N^N)(POP)]+ to [Cu(N^N)(xantphos)]+; introducing the iodo-functionality into the N^N domain leads to a red-shift in λmaxem compared to the complexes with the benchmark N^N ligand 5. In the solid state, [Cu(1)(POP)][PF6] and [Cu(1)(xantphos)][PF6] (fluoro-substituent) exhibit the highest PL quantum yields (74 and 25%, respectively) with values of Ï1/2 = 11.1 and 5.8 ÎŒs, respectively. Light-emitting electrochemical cells (LECs) with [Cu(N^N)(P^P)][PF6] complexes in the emissive layer have been tested. Using a block-wave pulsed current driving mode, the best performing device employed [Cu(1)(xantphos)]+ and this showed a maximum luminance (Lummax) of 129 cd mâ2 and a device lifetime (t1/2) of 54 h; however, the turn-on time (time to reach Lummax) was 4.1 h. Trends in performance data reveal that the introduction of fluoro-groups is beneficial, but that the incorporation of heavier halo-substituents leads to poor devices, probably due to a detrimental effect on charge transport; LECs with the iodo-functionalized N^N ligand 4 failed to show any electroluminescence after 50 h
Puncturing of lyophilized tissue engineered vascular matrices enhances the efficiency of their recellularization
Data on in vitro engineered "off the shelf" matrices support the concept of endogenous cellular repopulation driving the graft's remodeling via immune-mediated response. This seems important to further accelerate the cell reconstitution and may play a crucial role when mononuclear cells are used. Nevertheless, studies on decellularized xenogeneic grafts showed only limited host cell repopulation post-implantation. This study aims at a systematic comparison of reseeding methods (dripping, injection, bathing in a cell suspension and combined puncturing-dripping method) to define the most efficient technique enhancing recellularization of tissue engineered vascular matrices (patches, vessels, small diameter and standard size valves) prior implantation. The constructs were analyzed histologically, biochemically and biomechanically. Various preconditioning treatments (wet, lyophilized and air-dried) combined with reseeding methods demonstrated the highest cell loading efficiency, despite applied crimping and flow stress, of lyophilization followed by puncturing-dripping technique. This novel seeding method allows for an efficient, time saving graft reseeding that can be used within a one-step cardiovascular clinical intervention.
STATEMENT OF SIGNIFICANCE
The concept of living tissue engineered, self-repairing, autologous cardiovascular replacements, was proposed alternatively to existing synthetic/xenogeneic prostheses. Recent studies in animal models demonstrate faster in vivo recellularization after grafts pre-seeding with cells prior implantation. Pre-seeded cells hold either, the ability to differentiate directionally or attract host cells, crucial for graft integration and remodeling. It is unclear, however, how efficient the pre-loading is and how well cells withstand the flow. The study presents a systematic overview on cell loading techniques of different cardiovascular constructs, tested under static and dynamic conditions. Comparison illustrates a significantly higher efficiency of cells loading in lyophilized tissues punctured before their standard seeding. This technique may beneficially accelerate remodeling of cardiovascular grafts in further in vivo studies
A Hyperbaric Aerodynamic Levitator For Containerless Materials Research
A hyperbaric aerodynamic levitator has been developed for containerless materials research at specimen temperatures exceeding 2000 °C and pressures up to 10.3 MPa (1500 psi). This report describes the prototype instrument design and observations of the influence of specimen size, density, pressure, and flow rate on levitation behavior. The effect of pressure on heat transfer was also assessed by studying the heating and cooling behavior of levitated Al2O3 liquids. A threefold increase in the convective heat transfer coefficient was estimated as pressure increased to 10.3 MPa. The results demonstrate that hyperbaric aerodynamic levitation is a promising technique for containerless materials research at high gas pressures
An Activatable Cancer-Targeted Hydrogen Peroxide Probe for Photoacoustic and Fluorescence Imaging.
Reactive oxygen species play an important role in cancer, however, their promiscuous reactivity, low abundance, and short-lived nature limit our ability to study them in real time in living subjects with conventional noninvasive imaging methods. Photoacoustic imaging is an emerging modality for in vivo visualization of molecular processes with deep tissue penetration and high spatiotemporal resolution. Here, we describe the design and synthesis of a targeted, activatable probe for photoacoustic imaging, which is responsive to one of the major and abundant reactive oxygen species, hydrogen peroxide (H2O2). This bifunctional probe, which is also detectable with fluorescence imaging, is composed of a heptamethine carbocyanine dye scaffold for signal generation, a 2-deoxyglucose cancer localization moiety, and a boronic ester functionality that specifically detects and reacts to H2O2. The optical properties of the probe were characterized using absorption, fluorescence, and photoacoustic measurements; upon addition of pathophysiologic H2O2 concentrations, a clear increase in fluorescence and red-shift of the absorption and photoacoustic spectra were observed. Studies performed in vitro showed no significant toxicity and specific uptake of the probe into the cytosol in breast cancer cell lines. Importantly, intravenous injection of the probe led to targeted uptake and accumulation in solid tumors, which enabled noninvasive photoacoustic and fluorescence imaging of H2O2. In conclusion, the reported probe shows promise for the in vivo visualization of hydrogen peroxide. SIGNIFICANCE: This study presents the first activatable and cancer-targeted hydrogen peroxide probe for photoacoustic molecular imaging, paving the way for visualization of hydrogen peroxide at high spatiotemporal resolution in living subjects.Graphical Abstract: http://cancerres.aacrjournals.org/content/canres/79/20/5407/F1.large.jpg
A Comparative Photophysical Study of Structural Modifications of Thioflavin T-Inspired Fluorophores.
The benzothiazolium salt, Thioflavin T (ThT), has been widely adopted as the "gold-standard" fluorescent reporter of amyloid in vitro. Its properties as a molecular rotor result in a large-scale (âŒ1000-fold) fluorescence turn-on upon binding to ÎČ-sheets in amyloidogenic proteins. However, the complex photophysics of ThT combined with the intricate and varied nature of the amyloid binding motif means these interactions are poorly understood. To study this important class of fluorophores, we present a detailed photophysical characterization and comparison of a novel library of 12 ThT-inspired fluorescent probes for amyloid protein (PAPs), where both the charge and donor capacity of the heterocyclic and aminobenzene components have been interrogated, respectively. This enables direct photophysical juxtaposition of two structural groups: the neutral "PAP" (class 1) and the charged "mPAP" fluorophores (class 2). We quantify binding and optical properties at both the bulk and single-aggregate levels with some derivatives showing higher aggregate affinity and brightness than ThT. Finally, we demonstrate their abilities to perform super-resolution imaging of α-synuclein fibrils with localization precisions of âŒ16 nm. The properties of the derivatives provide new insights into the relationship between chemical structure and function of benzothiazole probes.EPSRC Follow on Fund, EPSRC DTC, Royal Society UR
Toxic Exposure of Songbirds to Lead in the Southeast Missouri Lead Mining District
Mining and smelting in the Southeast Missouri Lead Mining District has caused widespread contamination of soils with lead (Pb) and other metals. Soils from three study sites sampled in the district contained from approximately 1,000â3,200 mg Pb/kg. Analyses of earthworms [33â4,600 mg Pb/kg dry weight (dw)] collected in the district showed likely high Pb exposure of songbirds preying on soil organisms. Mean tissue Pb concentrations in songbirds collected from the contaminated sites were greater (p \u3c 0.05) than those in songbirds from reference sites by factors of 8 in blood, 13 in liver, and 23 in kidney. Ranges of Pb concentrations in livers (mg Pb/kg dw) were as follows: northern cardinal (Cardinalis cardinalis) = 0.11â3.0 (reference) and 1.3â30 (contaminated) and American robin (Turdus migratorius) = 0.43â8.5 (reference) and 7.6â72 (contaminated). Of 34 adult and juvenile songbirds collected from contaminated sites, 11 (32 %) had hepatic Pb concentrations that were consistent with adverse physiological effects, 3 (9 %) with systemic toxic effects, and 4 (12 %) with life-threatening toxic effects. Acid-fast renal intranuclear inclusion bodies, which are indicative of Pb poisoning, were detected in kidneys of two robins that had the greatest renal Pb concentrations (952 and 1,030 mg/kg dw). Mean activity of the enzyme delta-aminolevulinic acid dehydratase (ALAD) in red blood cells, a well-established bioindicator of Pb poisoning in birds, was decreased by 58â82 % in songbirds from the mining sites. We conclude that habitats within the mining district with soil Pb concentrations of C1,000 mg Pb/kg are contaminated to the extent that they are exposing ground-feeding songbirds to toxic concentrations of Pb
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