1,325 research outputs found

    Circadian Rhythms of Crawling and Swimming in the Nudibranch Mollusc Melibe leonina

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    Daily rhythms of activity driven by circadian clocks are expressed by many organisms, including molluscs. We initiated this study, with the nudibranch Melibe leonina, with four goals in mind: (1) determine which behaviors are expressed with a daily rhythm; (2) investigate which of these rhythmic behaviors are controlled by a circadian clock; (3) determine if a circadian clock is associated with the eyes or optic ganglia of Melibe, as it is in several other gastropods; and (4) test the hypothesis that Melibe can use extraocular photoreceptors to synchronize its daily rhythms to natural light-dark cycles. To address these goals, we analyzed the behavior of 55 animals exposed to either artificial or natural light-dark cycles, followed by constant darkness. We also repeated this experiment using 10 animals that had their eyes removed. Individuals did not express daily rhythms of feeding, but they swam and crawled more at night. This pattern of locomotion persisted in constant darkness, indicating the presence of a circadian clock. Eyeless animals also expressed a daily rhythm of locomotion, with more locomotion at night. The fact that eyeless animals synchronized their locomotion to the light-dark cycle suggests that they can detect light using extraocular photoreceptors. However, in constant darkness, these rhythms deteriorated, suggesting that the clock neurons that influence locomotion may be located in, or near, the eyes. Thus, locomotion in Melibe appears to be influenced by both ocular and extraocular photoreceptors, although the former appear to have a greater influence on the expression of circadian rhythms

    Development and Pilot of the Caregiver Strategies Inventory

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    Children with autism spectrum disorder often demonstrate unusual behavioral responses to sensory stimuli (i.e., sensory features). To manage everyday activities, caregivers may implement strategies to address these features during family routines. However, investigation of specific strategies used by caregivers is limited by the lack of empirically developed measures. In this study, we describe the development and pilot results of the Caregiver Strategies Inventory (CSI), a supplement to the Sensory Experiences Questionnaire Version 3.0 (SEQ 3.0; Baranek, 2009) that measures caregivers’ strategies in response to their children’s sensory features. Three conceptually derived and empirically grounded strategy types were tested: cognitive–behavioral, sensory–perceptual, and avoidance. Results indicated that the CSI demonstrated good internal consistency and that strategy use was related to child age and cognition. Moreover, parent feedback after completing the CSI supported its utility and social validity. The CSI may be used alongside the SEQ 3.0 to facilitate a family-centered approach to assessment and intervention planning

    Investigating the physical properties of transiting hot Jupiters with the 1.5-m Kuiper Telescope

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    We present new photometric data of 11 hot Jupiter transiting exoplanets (CoRoT-12b, HAT-P-5b, HAT-P-12b, HAT-P-33b, HAT-P-37b, WASP-2b, WASP-24b, WASP-60b, WASP-80b, WASP-103b, XO-3b) in order to update their planetary parameters and to constrain information about their atmospheres. These observations of CoRoT-12b, HAT-P-37b and WASP-60b are the first follow-up data since their discovery. Additionally, the first near-UV transits of WASP-80b and WASP-103b are presented. We compare the results of our analysis with previous work to search for transit timing variations (TTVs) and a wavelength dependence in the transit depth. TTVs may be evidence of a third body in the system and variations in planetary radius with wavelength can help constrain the properties of the exoplanet's atmosphere. For WASP-103b and XO-3b, we find a possible variation in the transit depths that may be evidence of scattering in their atmospheres. The B-band transit depth of HAT-P-37b is found to be smaller than its near-IR transit depth and such a variation may indicate TiO/VO absorption. These variations are detected from 2-4.6σ\sigma, so follow-up observations are needed to confirm these results. Additionally, a flat spectrum across optical wavelengths is found for 5 of the planets (HAT-P-5b, HAT-P-12b, WASP-2b, WASP-24b, WASP-80b), suggestive that clouds may be present in their atmospheres. We calculate a refined orbital period and ephemeris for all the targets, which will help with future observations. No TTVs are seen in our analysis with the exception of WASP-80b and follow-up observations are needed to confirm this possible detection.Comment: 18 pages, 7 figures, 9 Tables. Light Curves available online. Accepted to MNRAS (2017 August 25

    Polyglutamine disease: from pathogenesis to therapy

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    Polyglutamine diseases are inherited neurodegenerative conditions arising from expanded trinucleotide CAG repeats in the disease-causing gene, which are translated into polyglutamine tracts in the resultant protein. Although these diseases share a common type of mutation, emerging evidence suggests that pathogenesis is complex, involving disruption of key cellular pathways, and varying with the disease context. An understanding of polyglutamine disease mechanisms is critical for development of novel therapeutics. Here we summarise theories of molecular pathogenesis, and examine ways in which this knowledge is being harnessed for therapy, with reference to work under way at the University of Cape Town. Despite a plethora of preclinical data, clinical trials of therapies for polyglutamine diseases have had only limited success. However, recently initiated trials, including those using gene silencing approaches, should provide valuable insights into the safety and efficacy of therapies directly targeting polyglutamine pathogenesis. This is particularly relevant in the South African context, where the frequencies of two polyglutamine diseases, spinocerebellar ataxia types 1 and 7, are among the highest globally

    Generational differences in practice site selection criteria amongst primary care physicians.

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    Background and Objectives: Generational differences are often viewed as shaping the overall attitudes and actions of different age cohorts. It is essential to understand the motivations and generational differences in primary care physicians for efforts to recruit, retain, and educate the future physician workforce. Determining what factors most influence different generations of primary care physicians when choosing a practice site is essential to build our future primary care system. This study examined generational differences in the factors that attracted primary care physicians to their current practice. Methods: A survey instrument was mailed to all active members of the North Carolina Medical Board who listed their primary occupation as a primary care specialty. The survey consisted of 24 demographic questions regarding personal and practice variables and a list of 21 reasons for choosing a practice location measured on a 7-point Likert type scale. A total of 975 surveys were returned and usable for the final analysis, for a return rate of 34.5%. Data were analyzed using regression and correlation procedures to determine attitudes of each generation and factors that significantly influenced responses. Results: While slight differences between generations did exist, the overall choices for choosing a site remained stable across generations. Personality of the practice, on-call responsibilities, ability to practice comprehensive care, and location were deemed the most important factors for all generations. Differences between various demographic groups and Family Medicine versus other primary care specialties were minor with very little alteration of the top ten items being seen between groups. Conclusion: This study indicated that there were few differences between generations regarding primary reasons for choosing a practice site. In addition, factors remained remarkably similar across different specialties, family situations, genders, and ethnic groups. Several of the top reasons that primary care physicians indicate are the most important for site selection were also potentially modifiable, such as on-call responsibilities, practice personality, and ability to practice comprehensive care. Managers, clinicians, and educators can potentially utilize this information to better prepare and recruit current and future generations of primary care physicians.ECU Open Access Publishing Fun

    Generational differences in practice site selection criteria amongst primary care physicians.

    Get PDF
    ABSTRACT Background and Objectives: Generational differences are often viewed as shaping the overall attitudes and actions of different age cohorts. It is essential to understand the motivations and generational differences in primary care physicians for efforts to recruit, retain, and educate the future physician workforce. Determining what factors most influence different generations of primary care physicians when choosing a practice site is essential to build our future primary care system. This study examined generational differences in the factors that attracted primary care physicians to their current practice. Methods: A survey instrument was mailed to all active members of the North Carolina Medical Board who listed their primary occupation as a primary care specialty. The survey consisted of 24 demographic questions regarding personal and practice variables and a list of 21 reasons for choosing a practice location measured on a 7-point Likert type scale. A total of 975 surveys were returned and usable for the final analysis, for a return rate of 34.5%. Data were analyzed using regression and correlation procedures to determine attitudes of each generation and factors that significantly influenced responses. Results: While slight differences between generations did exist, the overall choices for choosing a site remained stable across generations. Personality of the practice, on-call responsibilities, ability to practice comprehensive care, and location were deemed the most important factors for all generations. Differences between various demographic groups and Family Medicine versus other primary care specialties were minor with very little alteration of the top ten items being seen between groups. Conclusion: This study indicated that there were few differences between generations regarding primary reasons for choosing a practice site. In addition, factors remained remarkably similar across different specialties, family situations, genders, and ethnic groups. Several of the top reasons that primary care physicians indicate are the most important for site selection were also potentially modifiable, such as on-call responsibilities, practice personality, and ability to practice comprehensive care. Managers, clinicians, and educators can potentially utilize this information to better prepare and recruit current and future generations of primary care physicians. Keywords: site selection, recruiting, generational differenc

    Using Three-Dimensional Printed Models for Trainee Orbital Fracture Education

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    BACKGROUND: Three-dimensional printing is an underutilized technology in ophthalmology training; its use must be explored in complex educational scenarios. This study described a novel approach to trainee education of orbital fracture repair utilizing three-dimensional (3D) printed models as a teaching tool. METHODS: Ophthalmology residents and oculoplastic fellows from multiple training institutions underwent an educational session on orbital fractures, learning through four different models. Participants analyzed orbital fractures through computerized tomography (CT) imaging alone and then utilizing CT imaging with the aid of a 3D printed model. Participants completed a questionnaire assessing their understanding of the fracture pattern and surgical approach. After the training, participants were surveyed on the impact of the educational session. Components of the training were rated by participants on a 5-point Likert scale. RESULTS: A statistically significant difference (p \u3c .05) was found in participant confidence conceptualizing the anatomic boundaries of the fracture and planning the orbital fracture approach for repair of three out of four models on pre-test post-test analysis. On exit questionnaire, 84.3% of participants thought the models were a useful tool for surgical planning, 94.8% of participants thought the models were a useful tool for conceptualizing the anatomic boundaries of the fracture, 94.8% of participants thought the models were a useful tool for orbital fracture training, and 89.5% of participants thought the exercise was helpful. CONCLUSION: This study supports the value of 3D printed models of orbital fractures as an effective tool for ophthalmology trainee education to improve understanding and visualization of complex anatomical space and pathology. Given the limited opportunities trainees may have for hands-on orbital fracture practice, 3D printed models provide an accessible way to enhance training

    The First Year Inventory: A longitudinal follow-up of 12-month-olds to 3 years of age

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    The First Year Inventory (FYI) is a parent-report measure designed to identify 12-month old infants at risk for autism spectrum disorder (ASD). The FYI taps behaviors that indicate risk in the developmental domains of sensory-regulatory and social-communication functioning. This longitudinal study is a follow-up of 699 children at 3 years of age from a community sample whose parents completed the FYI when their children were 12 months old. Parents of all 699 children completed the Social Responsiveness Scale – Preschool version (SRS-P) and the Developmental Concerns Questionnaire (DCQ) to determine age 3 developmental outcomes. In addition, children deemed at-risk for ASD based on liberal cut points on the FYI, SRS-P, and/or DCQ were invited for in-person diagnostic evaluations. We found 9 children who had a confirmed diagnosis of ASD from the sample of 699. ROC analyses determined that a two-domain cutoff score yielded optimal classification of children: 31% of those meeting algorithm cut-offs had ASD and 85% had a developmental disability or concern by age three. These results suggest that the FYI is a promising tool for identifying 12-month old infants who are at risk for an eventual diagnosis of ASD
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