2,710 research outputs found
Faculty Recital, Michelle Huang, piano
A Musical Journey through Visions & Pictures
featuring VCUarts graduates
Emma Willis and Oscar Knutsso
Overweight, Obesity, and Mental Illnesses: Weight Loss Treatment
For the past 30 years, overweight and obesity has increased at alarming rates in the general population. This public health crisis has affected persons with mental illnesses as it has those in the general population. Little is known about how individuals with psychiatric problems respond to weight-loss treatment compared to the general population. The current study examines the efficacy of a cognitive-behavioral group weight-loss intervention with such individuals. The study also examines self-esteem, motivation, and the involvement of a support person in treatment as predictor variables. The treatment was shown to be effective regardless of depression severity. However, while all participants with a support person completed the intervention, those without support were more likely to drop out. Participants also reported improvements in self esteem after treatment completion. Keywords: overweight, obesity, weight-loss, mental illness, depression, self-estee
Differences in Pragmatic Language Measures in Mothers of Children with Autism or Fragile X Syndrome
Mastery of pragmatics, which refers to the language used in different social interactions, is key to effective communication in daily life. However, studies have found that mothers of children with an autism spectrum disorder (ASD) or Fragile X Syndrome (FXS) are at an increased risk for impaired pragmatic language skills. Though many measures of pragmatic language exist for children, very few are available for these mothers. Two commonly used measures for the mothers include the Pragmatic Rating Scale (PRS) and the Pragmatic Language Subscale of the Broad Autism Phenotype Questionnaire (BAPQ). This study, unlike previous ones that only look at one measure, compares these two measures using cutoff scores. Subjects who score above a certain value are classified as “positive” for pragmatic language issues, and agreement refers to when the subject is classified positive by both measures. While high agreement was expected given the common purpose of the two measures, the results showed very low agreement. This was perhaps due to the small sample size and different testing methodologies used by the PRS and BAPQ. In the future, it may be helpful to conduct this study with a larger sample and/or bring in a third pragmatic language measure
Investigating ultrasound–light interaction in scattering media
Significance: Ultrasound-assisted optical imaging techniques, such as ultrasound-modulated optical tomography, allow for imaging deep inside scattering media. In these modalities, a fraction of the photons passing through the ultrasound beam is modulated. The efficiency by which the photons are converted is typically referred to as the ultrasound modulation’s “tagging efficiency.” Interestingly, this efficiency has been defined in varied and discrepant fashion throughout the scientific literature.
Aim: The aim of this study is the ultrasound tagging efficiency in a manner consistent with its definition and experimentally verify the contributive (or noncontributive) relationship between the mechanisms involved in the ultrasound optical modulation process.
Approach: We adopt a general description of the tagging efficiency as the fraction of photons traversing an ultrasound beam that is frequency shifted (inclusion of all frequency-shifted components). We then systematically studied the impact of ultrasound pressure and frequency on the tagging efficiency through a balanced detection measurement system that measured the power of each order of the ultrasound tagged light, as well as the power of the unmodulated light component.
Results: Through our experiments, we showed that the tagging efficiency can reach 70% in a scattering phantom with a scattering anisotropy of 0.9 and a scattering coefficient of 4 mm⁻¹ for a 1-MHz ultrasound with a relatively low (and biomedically acceptable) peak pressure of 0.47 MPa. Furthermore, we experimentally confirmed that the two ultrasound-induced light modulation mechanisms, particle displacement and refractive index change, act in opposition to each other.
Conclusion: Tagging efficiency was quantified via simulation and experiments. These findings reveal avenues of investigation that may help improve ultrasound-assisted optical imaging techniques
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Draft Genome Sequence of Bacillus velezensis CE2, Which Genetically Encodes a Novel Multicomponent Lantibiotic.
Bacillus velezensis CE2 produces potent antimicrobial compound(s). The draft genome sequence of the strain reported here is 4.1 Mb with a G+C content of 46.1%. Whole-genome sequencing revealed that the strain genetically encodes a novel multicomponent lantibiotic, velezensicidin
Resonant Scattering of Surface Plasmon Polaritons by Dressed Quantum Dots
The resonant scattering of surface plasmon-polariton waves by embedded
semiconductor quantum dots above the dielectric/metal interface is explored in
the strong-coupling regime. In contrast to non-resonant scattering by a
localized dielectric surface defect, a strong resonant peak in the scattering
field spectrum is predicted and accompanied by two side valleys. The peak
height depends nonlinearly on the amplitude of surface plasmon-polariton waves,
reflecting the feedback dynamics from a photon-dressed electron-hole plasma
inside the quantum dots. This unique behavior in the scattering field peak
strength is correlated with the occurrence of a resonant dip in the absorption
spectrum of surface plasmon-polariton waves due to interband photon-dressing
effect. Our result on the scattering of surface plasmon-polariton waves may be
experimentally observable and applied to spatially selective illumination and
imaging of individual molecules.Comment: 15 pages, 3 figure
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