7,632 research outputs found
Viewfinder/tracking system for Skylab
Basic component of system is infrared spectrometer designed for manual target acquisition, pointing and tracking, and data-take initiation. System incorporates three main subsystems which include: (1) viewfinder telescope, (2) control panel and electronics assembly, and (3) IR-spectrometer case assembly
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Physiological, behavioral and subjective sadness reactivity in frontotemporal dementia subtypes.
Frontotemporal dementia (FTD), a neurodegenerative disease broadly characterized by socioemotional impairments, includes three clinical subtypes: behavioral variant FTD (bvFTD), semantic variant primary progressive aphasia (svPPA) and non-fluent variant primary progressive aphasia (nfvPPA). Emerging evidence has shown emotional reactivity impairments in bvFTD and svPPA, whereas emotional reactivity in nfvPPA is far less studied. In 105 patients with FTD (49 bvFTD, 31 svPPA and 25 nfvPPA) and 27 healthy controls, we examined three aspects of emotional reactivity (physiology, facial behavior and subjective experience) in response to a sad film. In a subset of the sample, we also examined the neural correlates of diminished aspects of reactivity using voxel-based morphometry. Results indicated that all three subtypes of FTD showed diminished physiological responding in respiration rate and diastolic blood pressure; patients with bvFTD and svPPA also showed diminished subjective experience, and no subtypes showed diminished facial behavior. Moreover, there were differences among the clinical subtypes in brain regions where smaller volumes were associated with diminished sadness reactivity. These results show that emotion impairments extend to sadness reactivity in FTD and underscore the importance of considering different aspects of sadness reactivity in multiple clinical subtypes for characterizing emotional deficits and associated neurodegeneration in FTD
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Coherence between subjective experience and physiology in emotion: Individual differences and implications for well-being.
Emotion theorists have characterized emotions as involving coherent responding across various emotion response systems (e.g., covariation of subjective experience and physiology). Greater response system coherence has been theorized to promote well-being, yet very little research has tested this assumption. The current study examined whether individuals with greater coherence between physiology and subjective experience of emotion report greater well-being. We also examined factors that may predict the magnitude of coherence, such as emotion intensity, cognitive reappraisal, and expressive suppression. Participants (N = 63) completed self-report measures of well-being, expressive suppression, and cognitive reappraisal. They then watched a series of emotionally evocative film clips designed to elicit positive and negative emotion. During the films, participants continuously rated their emotional experience using a rating dial, and their autonomic physiological responses were recorded. Time-lagged cross-correlations were used to calculate within-participant coherence between intensity of emotional experience (ranging from neutral to very negative or very positive) and physiology (composite of cardiac interbeat interval, skin conductance, ear pulse transit time, finger pulse transit time and amplitude, systolic and diastolic blood pressure). Results indicated that individuals with greater coherence reported greater well-being. Coherence was highest during the most emotionally intense film and among individuals who reported lower expressive suppression. However, coherence was not associated with reappraisal. These findings provide support for the idea that greater emotion coherence promotes well-being and also shed light on factors that are associated with the magnitude of coherence. (PsycInfo Database Record (c) 2020 APA, all rights reserved)
Toward the Development of a Quick, Reliable Assessment Tool for Reflective Journals
Reflective practice, including reflective writing, can facilitate enriched learning, especially when implemented as part of a service-learning (SL) experience. Reflection is a central component of service-learning (SL) experiences. Students’ reflective abilities are often measured through reflective journaling; however, assessment of students’ reflective journals is not always efficient and straightforward. The goal of the present study was to establish a simple, reliable, and relatively quick tool for use by busy college instructors seeking to encourage students’ deep learning through reflective writing. A total of 258 reflective journals from 43 graduate students in speech-language pathology were evaluated by three raters using a three-tier assessment framework (nonreflection, reflection, and critical reflection) after Mezirow (1990) and Plack et al. (2005). Although previous studies found moderate to high interrater agreement and reliability, the current study did not support this finding. Strengths and weaknesses of the assessment framework and qualitative observations of the assessment process are discussed
Applied Force and sEMG Muscle Activity Required To Operate Pistol Grip Control in an Electric Utility Aerial Bucket
Electric utility line workers report high levels of fatigue in forearm muscles when operating a conventional pistol grip control in aerial buckets. This study measured the applied force and surface electromyographic (sEMG) signals from four upper extremity muscles required to operate the pistol grip control in two tasks. The first task was movement of the pistol grip in six directions (up/down, forward/rearward, clockwise/counter-clockwise), and the second task was movement of the bucket from its resting position on the truck bed to an overhead conductor on top of a 40 ft tall pole. The force applied to the pistol grip was measured in 14 aerial bucket trucks, and sEMG activity was measured on eight apprentice line workers.
The applied force required to move the pistol grip control in the six directions ranged from 12 to 15 lb. The sEMG activity in the extensor digitorum communis (EDC) forearm muscle was approximately twice as great or more than the other three muscles (flexor digitorum superficialis, triceps, and biceps). Line workers exerted 14 to 30% MVCEMG to move the pistol grip in the six directions. Average %MVCEMG of the EDC to move the bucket from the truck platform to an overhead line ranged from 26 to 30% across the four phases of the task. The sEMG findings from this study provide physiologic evidence to support the anecdotal reports of muscle fatigue from line workers after using the pistol grip control for repeated, long durations
Uncertainties of predictions from parton distribution functions II: the Hessian method
We develop a general method to quantify the uncertainties of parton
distribution functions and their physical predictions, with emphasis on
incorporating all relevant experimental constraints. The method uses the
Hessian formalism to study an effective chi-squared function that quantifies
the fit between theory and experiment. Key ingredients are a recently developed
iterative procedure to calculate the Hessian matrix in the difficult global
analysis environment, and the use of parameters defined as components along
appropriately normalized eigenvectors. The result is a set of 2d Eigenvector
Basis parton distributions (where d=16 is the number of parton parameters) from
which the uncertainty on any physical quantity due to the uncertainty in parton
distributions can be calculated. We illustrate the method by applying it to
calculate uncertainties of gluon and quark distribution functions, W boson
rapidity distributions, and the correlation between W and Z production cross
sections.Comment: 30 pages, Latex. Reference added. Normalization of Hessian matrix
changed to HEP standar
Comparison of Two Zooplankton Sampling Gears in Shallow, Homogeneous Lakes
We compared two zooplankton collection gears, Wisconsin nets and column samplers, to evaluate the effectiveness of each gear in quantifying inshore and offshore zooplankton density and size structure in shallow, homogeneous lakes. Zooplankton densities (within gear) did not differ (P \u3e 0.05) between inshore and offshore sites in either study lake, with the exception of Wisconsin-netted Cyclops sp. in Lake Goldsmith. Wisconsin net samples produced a higher mean zooplankton density than column samplers for Bosmina sp., Cyclops sp., and Daphnia sp. in East Oakwood Lake and for Cyclops sp. (inshore), Daphnia sp., and Diaptomus sp. in Lake Goldsmith. Zooplankton densities had greater variability (coefficients of variation) in 4 of 5 taxa collected with the Wisconsin net in both study lakes. Zooplankton size structure did not differ (P\u3e 0.05) between gears in either study lake, with the exception of Diaptomus sp. in East Oakwood Lake. Our results suggest that column samplers have higher precision than Wisconsin nets when sampling common zooplankton species in shallow, homogeneous lakes
Spirality: A Novel Way to Measure Spiral Arm Pitch Angle
We present the MATLAB code Spirality, a novel method for measuring spiral arm
pitch angles by fitting galaxy images to spiral templates of known pitch.
Computation time is typically on the order of 2 minutes per galaxy, assuming at
least 8 GB of working memory. We tested the code using 117 synthetic spiral
images with known pitches, varying both the spiral properties and the input
parameters. The code yielded correct results for all synthetic spirals with
galaxy-like properties. We also compared the code's results to two-dimensional
Fast Fourier Transform (2DFFT) measurements for the sample of nearby galaxies
defined by DMS PPak. Spirality's error bars overlapped 2DFFT's error bars for
26 of the 30 galaxies. The two methods' agreement correlates strongly with
galaxy radius in pixels and also with i-band magnitude, but not with redshift,
a result that is consistent with at least some galaxies' spiral structure being
fully formed by z=1.2, beyond which there are few galaxies in our sample. The
Spirality code package also includes GenSpiral, which produces FITS images of
synthetic spirals, and SpiralArmCount, which uses a one-dimensional Fast
Fourier Transform to count the spiral arms of a galaxy after its pitch is
determined. The code package is freely available online; see Comments for URL.Comment: 19 pages, 9 figures, 3 tables. The code package is available at
http://dafix.uark.edu/~doug/SpiralityCode
Identification of early gene expression changes in primary cultured neurons treated with topoisomerase I poisons.
Topoisomerase 1 (TOP1) poisons like camptothecin (CPT) are currently used in cancer chemotherapy but these compounds can have damaging, off-target effects on neurons leading to cognitive, sensory and motor deficits. To understand the molecular basis for the enhanced sensitivity of neurons to CPT, we examined the effects of compounds that inhibit TOP1-CPT, actinomycin D (ActD) and β-lapachone (β-Lap)-on primary cultured rat motor (MN) and cortical (CN) neurons as well as fibroblasts. Neuronal cells expressed higher levels of Top1 mRNA than fibroblasts but transcript levels are reduced in all cell types after treatment with CPT. Microarray analysis was performed to identify differentially regulated transcripts in MNs in response to a brief exposure to CPT. Pathway analysis of the differentially expressed transcripts revealed activation of ERK and JNK signaling cascades in CPT-treated MNs. Immediate-early genes like Fos, Egr-1 and Gadd45b were upregulated in CPT-treated MNs. Fos mRNA levels were elevated in all cell types treated with CPT; Egr-1, Gadd45b and Dyrk3 transcript levels, however, increased in CPT-treated MNs and CNs but decreased in CPT-treated fibroblasts. These transcripts may represent new targets for the development of therapeutic agents that mitigate the off-target effects of chemotherapy on the nervous system
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