3,026 research outputs found
Composite materials for space applications
The objectives of the program were to: generate mechanical, thermal, and physical property test data for as-fabricated advanced materials; design and fabricate an accelerated thermal cycling chamber; and determine the effect of thermal cycling on thermomechanical properties and dimensional stability of composites. In the current program, extensive mechanical and thermophysical property tests of various organic matrix, metal matrix, glass matrix, and carbon-carbon composites were conducted, and a reliable database was constructed for spacecraft material selection. Material property results for the majority of the as-fabricated composites were consistent with the predicted values, providing a measure of consolidation integrity attained during fabrication. To determine the effect of thermal cycling on mechanical properties, microcracking, and thermal expansion behavior, approximately 500 composite specimens were exposed to 10,000 cycles between -150 and +150 F. These specimens were placed in a large (18 cu ft work space) thermal cycling chamber that was specially designed and fabricated to simulate one year low earth orbital (LEO) thermal cycling in 20 days. With this rate of thermal cycling, this is the largest thermal cycling unit in the country. Material property measurements of the thermal cycled organic matrix composite laminate specimens exhibited less than 24 percent decrease in strength, whereas, the remaining materials exhibited less than 8 percent decrease in strength. The thermal expansion response of each of the thermal cycled specimens revealed significant reduction in hysteresis and residual strain, and the average CTE values were close to the predicted values
A sense of embodiment is reflected in people's signature size
BACKGROUND: The size of a person's signature may reveal implicit information about how the self is perceived although this has not been closely examined. METHODS/RESULTS: We conducted three experiments to test whether increases in signature size can be induced. Specifically, the aim of these experiments was to test whether changes in signature size reflect a person's current implicit sense of embodiment. Experiment 1 showed that an implicit affect task (positive subliminal evaluative conditioning) led to increases in signature size relative to an affectively neutral task, showing that implicit affective cues alter signature size. Experiments 2 and 3 demonstrated increases in signature size following experiential self-focus on sensory and affective stimuli relative to both conceptual self-focus and external (non-self-focus) in both healthy participants and patients with anorexia nervosa, a disorder associated with self-evaluation and a sense of disembodiment. In all three experiments, increases in signature size were unrelated to changes in self-reported mood and larger than manipulation unrelated variations. CONCLUSIONS: Together, these findings suggest that a person's sense of embodiment is reflected in their signature size
Evaluation of Representative Microbiological Sampling Sites of Goat and Sheep Dressed Carcasses
Statistical analysis of data of number of sampling points for microbial counts representing the entire goat/sheep carcass was carried out. Thirtytwo sampling points were evaluated out of which fourteen were found to represent the entire dressed carcass for assessing its hygienic efficacy
Developing a framework for arts in health programs targeting individuals with chronic pain: a mixed-methods study of practitioners
Objectives: Chronic pain is a leading cause of morbidity and disability across the world. Cultural engagement may be a valuable tool in addressing the social disconnection that often accompanies chronic pain. This study sought to develop a framework for arts in health programs targeting individuals with chronic pain. /
Study design: Sequential explanatory mixed-methods study. /
Methods: Web-based, cross-sectional survey sent to arts and cultural professionals to assess their experience with arts in health programming. Semi-structured interviews conducted with a sample of survey respondents to explore their perspectives on targeted arts in health programming for individuals with chronic pain. /
Results: Between October 2019 and January 2020, 208 surveys were completed by arts and cultural professionals. One hundred and twenty (58%) of the respondents indicated that they currently run an arts in health or museums in health program. Among these 120 respondents, 52 (43%) targeted older adults, 50 (42%) targeted individuals with mental health concerns, and 18 (15%) targeted individuals living with pain. Improving well-being (101 [84%]) and reducing social isolation (90 [75%]) were the most common intended program outcomes, while improving pain was the least common outcome (26 [22%]). Fifteen survey respondents were interviewed. Interviewees identified four interdependent themes regarding best practices for arts in health programs pertaining to (1) program content and structure, (2) program facilitation, (3) partnerships, and (4) programs for individuals with chronic pain. /
Conclusions: The cultural sector can support chronic pain prevention and treatment efforts through the development of specialized programs. This study provides a framework for developing arts in health programs that support individuals living with chronic pain
A deep learning pipeline for automatized assessment of spinal MRI
Background
This work evaluates the feasibility, development, and validation of a machine learning pipeline that includes all tasks from MRI input to the segmentation and grading of the intervertebral discs in the lumbar spine, offering multiple different radiological gradings of degeneration as quantitative objective output.
Methods
The pipelinesâ performance was analysed on 1âČ000 T2-weighted sagittal MRI. Binary outputs were assessed with the harmonic mean of precision and recall (DSC) and the area under the precision-recall curve (AUC-PR). Multi-class output scores were averaged and complemented by the Top-2 categorical accuracy. The processing success rate was evaluated on 10âČ053 unlabelled MRI scans of lumbar spines.
Results
The midsagittal plane selection achieved an DSC of 74,80% ± 2,99% and an AUC-PR score of 81.71% ± 2.72% (96.91% Top-2 categorical accuracy). The segmentation network obtained a DSC of 91.80% ± 0.44%. The Pfirrmann grading of intervertebral discs in the midsagittal plane was classified with a DSC of 64.08% ± 3.29% and an AUC-PR score of 68.25% ± 6.00% (91.65% Top-2 categorical accuracy). Disc herniations achieved a DSC of 61.57% ± 3.39% and an AUC-PR score of 66.86% ± 5.03%. The cranial endplate defects reached a DSC of 49.76% ± 3.45% and 52.36% ± 1.98% AUC-PR (slightly superior predictions of caudal endplate defect). The binary classifications for the caudal Schmorl's nodes obtained a DSC of 91.58% ± 2.25% with an AUC-PR metric of 96.69% ± 1.58% (similar performance for cranial Schmorl's nodes). Spondylolisthesis was classified with a DSC of 89.03% ± 2.42% and an AUC-PR score of 95.98% ± 1.82%. Annular Fissures were predicted with a DSC of 78.09% ± 7.21% and an AUC-PR score of 86.31% ± 7.45%. Intervertebral disc classifications in the parasagittal plane achieved an equivalent performance. The pipeline successfully processed 98.53% of the provided sagittal MRI scans.
Conclusions
The present deep learning framework has the potential to aid the quantitative evaluation of spinal MRI for an array of clinically established grading systems. + Graphical abstrac
Capacity building for GIS-based SDG indicators analysis with global high-resolution land cover datasets
The support of geospatial data and technologies for the United Nations Sustainable Development Goals (SDG) framework is critical
for assessing and monitoring key indicators, revealing the planetâs trajectory towards sustainability. The availability of global open
geospatial datasets, especially high-resolution land cover datasets, provides significant opportunities for computing and comparing
indicators across different regions and scales. However, barriers to their proficient use remain due to a lack of data awareness,
management and processing capacities using geographic information systems software. To address this, the âCapacity Building for
GIS-based SDG Indicator Analysis with Global High-resolution Land Cover Datasetsâ project created open training material on
discovering, accessing, and manipulating global geospatial datasets for computing SDG indicators. The material focuses on water
and terrestrial ecosystems, urban environments, and climate, by leveraging world-class global geospatial datasets and using the Free
and Open Source Software QGIS. The training material is released under a Creative Commons Attribution 4.0 License, ensuring
broad accessibility and facilitating continuous improvement.The Educational and Capacity Building Initiative 2022 of the International Society for Photogrammetry and Remote Sensing (ISPRS).https://www.isprs.org/publications/archives.aspxam2024Geography, Geoinformatics and MeteorologySDG-02:Zero HungerSDG-06:Clean water and sanitationSDG-09: Industry, innovation and infrastructureSDG-11:Sustainable cities and communitiesSDG-12:Responsible consumption and productionSDG-13:Climate actionSDG-14:Life below waterSDG-15:Life on lan
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18 Nov 2013 In situ detection of electrified aerosols in the upper troposphere and stratosphere
Electrified aerosols have been observed in the
lower troposphere and in the mesosphere, but have never
been detected in the stratosphere and upper troposphere. We
present measurements of aerosols obtained during a balloon
flight to an altitude of 24 km. The measurements were per-
formed with an improved version of the Stratospheric and
Tropospheric Aerosol Counter (STAC) aerosol counter dedi-
cated to the search for charged aerosols. It is found that most of the aerosols are charged in the upper troposphere for altitudes below 10 km and in the stratosphere for altitudes above 20 km. Conversely, the aerosols seem to be uncharged between 10 km and 20 km. Model calculations are used to quantify the electrification of the aerosols with a stratospheric aerosolâion model. The percentages of charged aerosols obtained with model calculations are in excellent agreement with the observations below 10 km and above 20 km. However, the model cannot reproduce the absence of electrification found in the lower stratosphere, as the processes leading to neutralisation in this altitude range are unknown. The presence of sporadic transient layers of electrified aerosol in the upper troposphere and in the stratosphere could have significant implications for sprite formatio
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