Catalogue Search | MBRL
Are you sure you want to remove the book from the shelf?
{{itemTitle}}
926
result(s) for
"Reich, W."
Sort by:
Layered liquid crystal elastomer actuators
Liquid crystalline elastomers (LCEs) are soft, anisotropic materials that exhibit large shape transformations when subjected to various stimuli. Here we demonstrate a facile approach to enhance the out-of-plane work capacity of these materials by an order of magnitude, to nearly 20 J/kg. The enhancement in force output is enabled by the development of a room temperature polymerizable composition used both to prepare individual films, organized via directed self-assembly to retain arrays of topological defect profiles, as well as act as an adhesive to combine the LCE layers. The material actuator is shown to displace a load >2500× heavier than its own weight nearly 0.5 mm.
Liquid crystalline elastomers (LCE) exhibit shape transformation when subjected to various stimuli, but the achievable thickness of LCE films is limited. Here the authors demonstrate arbitrarily thick LCE films that are continuous in composition and maintain the director orientation, prescribed into the material.
Journal Article
The resilience handbook : approaches to stress and trauma
\"How are people and communities able to prevail despite challenge? What helps them bounce back from adversity and even grow in knowledge and understanding? And can this resilience be taught? During the past decade, exciting scientific advances have shed light on how resilience operates from neurons to neighborhoods. In The Resilience Handbook, experts in the science of resilience draw on human and animal research to describe the process of resilience and follow its course as it unfolds both within individuals and in social networks. Contributors also highlight the promise of new interventions that apply what we know about resilience processes to bolster positive health, and raise some of the pressing questions and issues for the field as it matures.\" -- Publisher's description.
Book
Robust optimal design and trajectory planning of an aircraft with morphing airfoil sections
Aircraft performance is heavily dependent on how an aircraft’s design interacts with the flight trajectories and missions that it flies. An optimal aircraft must, thus, optimize both the physical design of the aircraft alongside its flight trajectories. However, an aircraft design optimized for either a single trajectory or a small number of trajectories is likely to be overspecialized, and may perform poorly when flying other trajectories. This paper presents an approach for designing an airfoil for a morphing aircraft wing while optimizing its worst-case flight time to states defined within a continuous range of different flight states. Sampling-based motion planning techniques are used to plan optimal flight trajectories for each design evaluated during design optimization. Several improvements to methods for using sampling-based motion planning as a subproblem within a design optimization problem are presented. An approach for defining a suitable continuous set of flight states is proposed to ensure that only reachable states are used when determining the optimal aircraft design. A robust optimization approach is used in order to solve the resulting optimization problem. Results are presented comparing the design found using the proposed robust optimization approach against a multi-objective design and motion planning approach previously used in the literature. The results show that the designs found using the robust optimization approach have better worst-case flight times than those found using the multi-objective approach. The results also indicate that the robust optimization approach is able to find a design which avoids overspecialization, unlike those found by the multi-objective approach.
Journal Article
Vulnerability to stress among women in chronic pain from fibromyalgia and osteoarthritis
In two investigations, we studied vulnerability to the negative effects of stress among women in chronic pain from 2 types of musculoskeletal illnesses, fibromyalgia syndrome (FMS) and osteoarthritis (OA). In Study 1, there were 101 female participants 50 to 78 years old: 50 had FMS, 29 had OA knee pain and were scheduled for knee surgery, and 22 had OA but were not planning surgery. Cross-sectional analyses showed that the three groups were comparable on demographic variables, personality attributes, negative affect, active coping, and perceived social support. As expected, FMS and OA surgery women reported similar levels of bodily pain, and both groups scored higher than OA nonsurgery women. However, women with FMS reported poorer emotional and physical health, lower positive affect, a poorer quality social milieu, and more frequent use of avoidant coping with pain than did both groups of women with OA. Moreover, the perception and use of social support were closely tied to perceived social stress only among the FMS group. In Study 2, we experimentally manipulated negative mood and stress in 41 women 37 to 74 years old: 20 women had FMS, and 21 women had OA. Participantsfrom each group were randomly assigned to either a negative mood induction or a neutral mood (control) condition, and then all participants discussed a stressful interpersonal eventfor 30 min. Stress-related increases in pain were exacerbated by negative mood induction among women with FMS but not women with OA, and pain during stress was associated with decreases in positive affect in women with FMS but not women with OA. These findings suggest that among women with chronic pain, those with FMS may be particularly vulnerable to the negative effects of social stress. They have fewer positive affective resources, use less effective pain-coping strategies, and have more constrained social networks than their counterparts with OA, particularly those who experience similar levels ofpain. They also seem to experience more prolonged stress-related increases in pain under certain circumstances, all of which may contribute to a lowering of positive affect and increased stress reactivity over time.
Journal Article
Depression History, Stress, and Pain in Rheumatoid Arthritis Patients
This study examined the role of past episodes of depression on pain reports for patients with rheumatoid arthritis (RA) before and during stress induction. A history of major depressive episodes was assessed by diagnostic interviews for 138 RA patients, 74 who later participated in a set of laboratory procedures designed to induce interpersonal stress. Patients were evaluated by a rheumatologist and then asked to report joint and bodily pain throughout the laboratory study. We found that RA patients with a history of two or more episodes of major depression had more pain at baseline, and exhibited higher pain in response to the stress induction than did RA patients with either only one episode or no history of depression. Such findings provide new insight in the dynamic relationships between depression, stress, and pain.
Journal Article
LOFAR in Germany
The LOw Frequency ARray – LOFAR – is a new fully digital radio telescope designed for frequencies between 30 MHz and 240 MHz centered in the Netherlands. In May 2006 ten German institutes formed the German LOng Wavelength consortium – GLOW – to coordinate its contributions and scientific interests to the LOFAR project. The first LOFAR station CS1 was installed in summer 2006 near Exloo/Netherlands. The second station IS-G1 is presently been placed in the immediate vicinity of the Effelsberg 100-m radio telescope near Bad Münstereifel/Germany. This contribution briefly describes the basic properties and aims of LOFAR, the aims of the GLOW consortium and the actual activities to install a LOFAR station at the Effelsberg site.
Journal Article
Affect and pain in rheumatoid arthritis: Do individual differences in affective regulation and affective intensity predict emotional recovery from pain?
Individual differences in adaptation to rheumatoid arthritis are not fully accounted for by illness severity or duration of symptoms.
In this study, we assessed differences in affect regulation and affect intensity as variables that might be important for identifying women with rheumatoid arthritis who are resilient versus those who have disrupted moods following pain exacerbations.
Specifically, affective regulation, affect intensity, active coping, neuroticism and weekly reports of pain, positive affect, and negative affect were assessed in a sample of 81 women diagnosed with rheumatoid arthritis.
Our results indicated that affective regulation, affect intensity, and active coping played important but distinct roles in the ebb and flow of negative and positive affect. In particular, active coping was related to positive affect, whereas affective regulation and affect intensity showed interactive effects, moderating the prospective relationship between pain and negative affect and pain and positive affect.
Overall, this study suggests that recovery from rheumatoid arthritis pain can be swift, except for those women who have difficulty regulating strong unpleasant affect.
Journal Article