Computation of forces in strongly nonlinear magnetic fields using higher-order eggshell algorithm

A novel version of the eggshell-based procedure for numerical computation of magnetic forces and torques acting on ferromagnetic bodies in highly nonlinear magnetic fields is presented. The procedure works with a fully adaptive higher-order finite element method developed for years in our research group, that is implemented in own code Agros2D and library Hermes. The power of the methodology and both codes is demonstrated on the solution of two typical examples: computation of the static characteristic of a magnetic actuator and torque characteristic of a flux-switched permanent-magnet machine. The results obtained are compared with data calculated by several other available codes

Assessing plant-to-plant communication and induced resistance in sagebrush using the sagebrush specialist Trirhabda pilosa

Plants respond to damage by herbivores or to reliable cues of damage by changing in ways that provide greater resistance and increase their fitness. Sagebrush has been a model system for understanding induced resistance, although resistance in this system is commonly assessed by quantifying damage at the end of the season; this measure is slow and lacks accuracy and interpretability because so many other factors also affect levels of damage. Herbivore choice offers a potentially rapid and accurate alternative assay of induced resistance. Here we evaluate whether feeding behavior of a specialized Chrysomelid beetle, Trirhabda pilosa, could be used to assay induced changes in plant quality. Beetle larvae were offered the choice between two leaves in Petri dish arenas. We found that beetles avoided leaves that were naturally damaged by herbivores, experimentally clipped with scissors, and exposed to the volatiles from naturally or experimentally damaged neighboring leaves compared to control leaves. Experiments varied the source of the damage, the duration of the feeding test, and how damage was measured, still, beetles consistently preferred uninduced controls by a 2:1 ratio over leaves exposed to cues of damage. These results suggest that behavioral assays using T. pilosa larvae can be used to rapidly evaluate induced resistance in this system. More generally, movement and feeding behaviors of herbivores are an important and underappreciated component of induced plant responses

Resolvent modelling of jet noise: the need for forcing models

The singular value decomposition of the mean-flow-based resolvent operator, or resolvent analysis, has proven to provide essential insights into the dynamics of various turbulent flows. In this study, we perform a resolvent analysis of a compressible turbulent jet, where the optimisation domain of the response modes is located in the acoustic field, excluding the hydrodynamic region, in order to promote acoustically efficient modes. We examine the properties of the acoustic resolvent and assess its potential for jet-noise modelling, focusing on the subsonic regime. We compare resolvent modes with SPOD modes educed from LES data. Resolvent forcing modes, consistent with previous studies, are found to contain supersonic waves associated with Mach wave radiation in the response modes. This differs from the standard resolvent in which hydrodynamic instabilities dominate. Acoustic resolvent response modes generally have better alignment with acoustic SPOD modes than standard resolvent response modes. For the optimal mode, the angle of the acoustic beam is close to that found in SPOD modes for moderate frequencies. However, there is no significant separation between the singular values of the leading and sub-optimal modes. Some suboptimal modes are furthermore shown to contain irrelevant structure for jet noise. Thus, even though it contains essential acoustic features absent from the standard resolvent approach, the SVD of the acoustic resolvent alone is insufficient to educe a low-rank model for jet noise. But because it identifies the prevailing mechanisms of jet noise, it provides valuable guidelines in the search of a forcing model (Karban $\textit{et al.}$ 2022, An empirical model of noise sources in subsonic jets. arXiv preprint arXiv:2210.01866).Comment: 24 pages, 20 figure

Towards a middle-range theory of mental health and well-being effects of employment transitions: Findings from a qualitative study on unemployment during the 2009-2010 economic recession.

This article builds upon previous theoretical work on job loss as a status passage to help explain how people's experiences of involuntary unemployment affected their mental well-being during the 2009-2010 economic recession. It proposes a middle-range theory that interprets employment transitions as status passages and suggests that their health and well-being effects depend on the personal and social meanings that people give to them, which are called properties of the transitions. The analyses, which used a thematic approach, are based on the findings of a qualitative study undertaken in Bradford (North England) consisting of 73 people interviewed in 16 focus groups. The study found that the participants experienced their job losses as divestment passages characterised by three main properties: experiences of reduced agency, disruption of role-based identities, for example, personal identity crises, and experiences of 'spoiled identities', for example, experiences of stigma. The proposed middle-range theory allows us to federate these findings together in a coherent framework which makes a contribution to illuminating not just the intra-personal consequences of unemployment, that is, its impact on subjective well-being and common mental health problems, but also its inter-personal consequences, that is, the hidden and often overlooked social processes that affect unemployed people's social well-being. This article discusses how the study findings and the proposed middle-range theory can help to address the theoretical weaknesses and often contradictory empirical findings from studies that use alternative frameworks, for example, deprivation models and 'incentive theory' of unemployment

Water-Borne Cues of a Non-Indigenous Seaweed Mediate Grazer-Deterrent Responses in Native Seaweeds, but Not Vice Versa

Plants optimise their resistance to herbivores by regulating deterrent responses on demand. Induction of anti-herbivory defences can occur directly in grazed plants or from emission of risk cues to the environment, which modifies interactions of adjacent plants with, for instance, their consumers. This study confirmed the induction of anti-herbivory responses by water-borne risk cues between adjoining con-specific seaweeds and firstly examined whether plant-plant signalling also exists among adjacent hetero-specific seaweeds. Furthermore, differential abilities and geographic variation in plant-plant signalling by a non-indigenous seaweed as well as native seaweeds were assessed. Twelve-day induction experiments using the non-indigenous seaweed Sargassum muticum were conducted in the laboratory in Portugal and Germany with one local con-familiar (Portugal: Cystoseira humilis, Germany: Halidrys siliquosa) and hetero-familiar native species (Portugal: Fucus spiralis, Germany: F. vesiculosus). All seaweeds were grazed by a local isopod species (Portugal: Stenosoma nadejda, Germany: Idotea baltica) and were positioned upstream of con- and hetero-specific seaweeds. Grazing-induced modification in seaweed traits were tested in three-day feeding assays between cue-exposed and cue-free ( = control) pieces of both fresh and reconstituted seaweeds. Both Fucus species reduced their palatability when positioned downstream of isopod-grazed con-specifics. Yet, the palatability of non-indigenous S. muticum remained constant in the presence of upstream grazed con-specifics and native hetero-specifics. In contrast, both con-familiar (but neither hetero-familiar) native species reduced palatability when located downstream of grazed S. muticum. Similar patterns of grazer-deterrent responses to water-borne cues were observed on both European shores, and were almost identical between assays using fresh and reconstituted seaweeds. Hence, seaweeds may use plant-plant signalling to optimise chemical resistance to consumers, though this ability appeared to be species-specific. Furthermore, this study suggests that native species may benefit more than a non-indigenous species from water-borne cue mediated reduction in consumption as only natives responded to signals emitted by hetero-specifics

Include me in: user involvement in research and evaluation

yesPurpose: This paper discusses the experiences of a group of ten user and carer researchers from mental health and learning disability services who worked together in a research and evaluation project between 2009 and 2012. The research project aimed to identify changes that took place as over 300 people moved from hostel accommodation into independent tenancies in flats and bungalows. These moves were part of a three year project involving a partnership between a local authority and a housing association. Design / approach: The paper describes the process of involving user and carers in the research process, identifying the challenges and benefits of involving users and carers. The ways in which people were trained and supported to take part and stay involved are outlined, as well as how the group felt they learnt new skills and increased their confidence. Findings: User involvement in research can mean different things with different levels of involvement, from consultation through to user-controlled research. The collaborative study had a range of benefits for the lives of the co-researchers, as well as contributing to the development of a new independent living service. A number of factors contribute to the success of user involvement in research and these are listed. Originality / value: This paper adds the voices of the co-researchers to the literature and provides ‘lessons learned’ for other researchers in this area

Ambiguity in mean-flow-based linear analysis

Abstract</jats:p

Messages from the other side: parasites receive damage cues from their host plants

As sessile organisms, plants rely on their environment for cues indicating imminent herbivory. These cues can originate from tissues on the same plant or from different individuals. Since parasitic plants form vascular connections with their host, parasites have the potential to receive cues from hosts that allow them to adjust defenses against future herbivory. However, the role of plant communication between hosts and parasites for herbivore defense remains poorly investigated. Here we examined the effects of damage to lupine hosts (Lupinus texensis) on responses of the attached hemiparasite (Castilleja indivisa), and indirectly, on a specialist herbivore of the parasite, buckeyes (Junonia coenia). Lupines produce alkaloids as defenses against herbivore that can be taken up by the parasite. We found that damage to lupine host plants by beet armyworm (Spodoptera exigua) significantly increased jasmonic acid (JA) levels in both the lupine host and parasite, suggesting uptake of phytohormones or priming of parasite defenses using host cues. However, lupine host damage did not induce changes in alkaloid levels in the hosts or parasites. Interestingly, the parasite had substantially higher concentrations of JA and alkaloids compared to lupine host plants. Buckeye herbivores consumed more parasite tissue when attached to damaged compared to undamaged hosts. We hypothesize that increased JA due to lupine host damage induced higher iridoid glycosides in the parasite, which are feeding stimulants for this specialist herbivore. Our results demonstrate that damage to hosts may affect both parasites and associated herbivores, indicating cascading effects of host damage on multiple trophic levels

Tensor analyzing powers for 7 Li induced transfer breakup reactions

The T20 analyzing powers have been measured for the 12Sn(7Li ,8Be2a) 119In and 120Sn (7Li ,6Li*a+d) 121Sn transfer breakup reactions, using a 70 MeV beam. The data exhibit excellent agreement with the results of coupled reaction channels calculations, providing an important test of these calculations when applied to the transfer breakup reaction mechanism

Herbivore-induced shifts in carbon and nitrogen allocation in red oak seedlings

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/65993/1/j.1469-8137.2008.02420.x.pd