SwePub
Sök i SwePub databas

  Extended search

Träfflista för sökning "WFRF:(Moffat C) "

Search: WFRF:(Moffat C)

  • Result 1-20 of 20
Sort/group result
   
EnumerationReferenceCoverFind
1.
  • Weigelt, G., et al. (author)
  • VLTI-MATISSE chromatic aperture-synthesis imaging of eta Carinae's stellar wind across the Br alpha line Periastron passage observations in February 2020
  • 2021
  • In: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 652
  • Journal article (peer-reviewed)abstract
    • Context. Eta Carinae is a highly eccentric, massive binary system (semimajor axis similar to 15.5 au) with powerful stellar winds and a phase-dependent wind-wind collision (WWC) zone. The primary star, eta Car A, is a luminous blue variable (LBV); the secondary, eta Car B, is a Wolf-Rayet or O star with a faster but less dense wind. Aperture-synthesis imaging allows us to study the mass loss from the enigmatic LBV eta Car. Understanding LBVs is a crucial step toward improving our knowledge about massive stars and their evolution. Aims. Our aim is to study the intensity distribution and kinematics of eta Car's WWC zone. Methods. Using the VLTI-MATISSE mid-infrared interferometry instrument, we perform Br alpha imaging of eta Car's distorted wind. Results. We present the first VLTI-MATISSE aperture-synthesis images of eta Car A's stellar windin several spectral channels distributed across the Br alpha 4.052 mu m line (spectral resolving power R similar to 960). Our observations were performed close to periastron passage in February 2020 (orbital phase similar to 14.0022). The reconstructed iso-velocity images show the dependence of the primary stellar wind on wavelength or line-of-sight (LOS) velocity with a spatial resolution of 6 mas (similar to 14 au). The radius of the faintest outer wind regions is similar to 26 mas (similar to 60 au). At several negative LOS velocities, the primary stellar wind is less extended to the northwest than in other directions. This asymmetry is most likely caused by the WWC. Therefore, we see both the velocity field of the undisturbed primary wind and the WWC cavity. In continuum spectral channels, the primary star wind is more compact than in line channels. A fit of the observed continuum visibilities with the visibilities of a stellar wind CMFGEN model (CMFGEN is an atmosphere code developed to model the spectra of a variety of objects) provides a full width at half maximum fit diameter of the primary stellar wind of 2.84 +/- 0.06 mas (6.54 +/- 0.14 au). We comparethe derived intensity distributions with the CMFGEN stellar wind model and hydrodynamic WWC models.
  •  
2.
  • Wade, G. A., et al. (author)
  • The MiMeS survey of magnetism in massive stars : introduction and overview
  • 2016
  • In: Monthly notices of the Royal Astronomical Society. - : Oxford University Press (OUP). - 0035-8711 .- 1365-2966. ; 456:1, s. 2-22
  • Journal article (other academic/artistic)abstract
    • The MiMeS (Magnetism in Massive Stars) project is a large-scale, high-resolution, sensitive spectropolarimetric investigation of the magnetic properties of O- and early B-type stars. Initiated in 2008 and completed in 2013, the project was supported by three Large Program allocations, as well as various programmes initiated by independent principal investigators, and archival resources. Ultimately, over 4800 circularly polarized spectra of 560 O and B stars were collected with the instruments ESPaDOnS (Echelle SpectroPolarimetric Device for the Observation of Stars) at the Canada-France-Hawaii Telescope, Narval at the Telescope Bernard Lyot and HARPSpol at the European Southern Observatory La Silla 3.6 m telescope, making MiMeS by far the largest systematic investigation of massive star magnetism ever undertaken. In this paper, the first in a series reporting the general results of the survey, we introduce the scientific motivation and goals, describe the sample of targets, review the instrumentation and observational techniques used, explain the exposure time calculation designed to provide sensitivity to surface dipole fields above approximately 100 G, discuss the polarimetric performance, stability and uncertainty of the instrumentation, and summarize the previous and forthcoming publications.
  •  
3.
  • Woitowich, N. C., et al. (author)
  • Structural basis for light control of cell development revealed by crystal structures of a myxobacterial phytochrome
  • 2018
  • In: Iucrj. - : International Union of Crystallography (IUCr). - 2052-2525. ; 5:Part 5, s. 619-634
  • Journal article (peer-reviewed)abstract
    • Phytochromes are red-light photoreceptors that were first characterized in plants, with homologs in photosynthetic and non-photosynthetic bacteria known as bacteriophytochromes (BphPs). Upon absorption of light, BphPs interconvert between two states denoted Pr and Pfr with distinct absorption spectra in the red and far-red. They have recently been engineered as enzymatic photoswitches for fluorescent-marker applications in non-invasive tissue imaging of mammals. This article presents cryo- and room-temperature crystal structures of the unusual phytochrome from the non-photosynthetic myxobacterium Stigmatella aurantiaca (SaBphP1) and reveals its role in the fruitingbody formation of this photomorphogenic bacterium. SaBphP1 lacks a conserved histidine (His) in the chromophore-binding domain that stabilizes the Pr state in the classical BphPs. Instead it contains a threonine (Thr), a feature that is restricted to several myxobacterial phytochromes and is not evolutionarily understood. SaBphP1 structures of the chromophore binding domain (CBD) and the complete photosensory core module (PCM) in wild-type and Thr-to-His mutant forms reveal details of the molecular mechanism of the Pr/Pfr transition associated with the physiological response of this myxobacterium to red light. Specifically, key structural differences in the CBD and PCM between the wild-type and the Thr-to-His mutant involve essential chromophore contacts with proximal amino acids, and point to how the photosignal is transduced through the rest of the protein, impacting the essential enzymatic activity in the photomorphogenic response of this myxobacterium.
  •  
4.
  • Gaffney, K J, et al. (author)
  • Observation of structural anisotropy and the onset of liquidlike motion during the nonthermal melting of InSb
  • 2005
  • In: Physical Review Letters. - : American Physical Society. - 0031-9007 .- 1079-7114. ; 95:12
  • Journal article (peer-reviewed)abstract
    • The melting dynamics of laser excited InSb have been studied with femtosecond x-ray diffraction. These measurements observe the delayed onset of diffusive atomic motion, signaling the appearance of liquidlike dynamics. They also demonstrate that the root-mean-squared displacement in the [111] direction increases faster than in the [110] direction after the first 500 fs. This structural anisotropy indicates that the initially generated fluid differs significantly from the equilibrium liquid.
  •  
5.
  •  
6.
  •  
7.
  • Dean, E., et al. (author)
  • Health Competency Standards in Physical Therapist Practice
  • 2019
  • In: Physical Therapy. - : NLM (Medline). - 0031-9023 .- 1538-6724. ; 99:9, s. 1242-1254
  • Journal article (peer-reviewed)abstract
    • Although the physical therapist profession is the leading established, largely nonpharmacological health profession in the world and is committed to health promotion and noncommunicable disease (NCD) prevention, these have yet to be designated as core physical therapist competencies. Based on findings of 3 Physical Therapy Summits on Global Health, addressing NCDs (heart disease, cancer, hypertension, stroke, diabetes, obesity, and chronic lung disease) has been declared an urgent professional priority. The Third Summit established the status of health competencies in physical therapist practice across the 5 World Confederation for Physical Therapy (WCPT) regions with a view to establish health competency standards, this article's focus. Three general principles related to health-focused practice emerged, along with 3 recommendations for its inclusion. Participants acknowledged that specific competencies are needed to ensure that health promotion and NCD prevention are practiced consistently by physical therapists within and across WCPT regions (ie, effective counseling for smoking cessation, basic nutrition, weight control, and reduced sitting and increased activity/exercise in patients and clients, irrespective of their presenting complaints/diagnoses). Minimum accreditable health competency standards within the profession, including use of the WCPT-supported Health Improvement Card, were recommended for inclusion into practice, entry-to-practice education, and research. Such standards are highly consistent with the mission of the WCPT and the World Health Organization. The physical therapist profession needs to assume a leadership role vis-à-vis eliminating the gap between what we know unequivocally about the causes of and contributors to NCDs and the long-term benefits of effective, sustained, nonpharmacological lifestyle behavior change, which no drug nor many surgical procedures have been reported to match.
  •  
8.
  • Horger, B A, et al. (author)
  • Neurturin exerts potent actions on survival and function of midbrain dopaminergic neurons
  • 1998
  • In: The Journal of Neuroscience. - 1529-2401. ; 18:13, s. 4929-4937
  • Journal article (peer-reviewed)abstract
    • Glial cell line-derived neurotrophic factor (GDNF) exhibits potent effects on survival and function of midbrain dopaminergic (DA) neurons in a variety of models. Although other growth factors expressed in the vicinity of developing DA neurons have been reported to support survival of DA neurons in vitro, to date none of these factors duplicate the potent and selective actions of GDNF in vivo. We report here that neurturin (NTN), a homolog of GDNF, is expressed in the nigrostriatal system, and that NTN exerts potent effects on survival and function of midbrain DA neurons. Our findings indicate that NTN mRNA is sequentially expressed in the ventral midbrain and striatum during development and that NTN exhibits survival-promoting actions on both developing and mature DA neurons. In vitro, NTN supports survival of embryonic DA neurons, and in vivo, direct injection of NTN into the substantia nigra protects mature DA neurons from cell death induced by 6-OHDA. Furthermore, administration of NTN into the striatum of intact adult animals induces behavioral and biochemical changes associated with functional upregulation of nigral DA neurons. The similarity in potency and efficacy of NTN and GDNF on DA neurons in several paradigms stands in contrast to the differential distribution of the receptor components GDNF Family Receptor alpha1 (GFRalpha1) and GFRalpha2 within the ventral mesencephalon. These results suggest that NTN is an endogenous trophic factor for midbrain DA neurons and point to the possibility that GDNF and NTN may exert redundant trophic influences on nigral DA neurons acting via a receptor complex that includes GFRalpha1.
  •  
9.
  •  
10.
  • Brorson, Håkan, et al. (author)
  • Liposuction
  • 2006
  • In: Lymphedema framework: Best practice for the management of lymphoedema. International consensus. ; , s. 50-50
  • Book chapter (peer-reviewed)
  •  
11.
  • Edlund, Petra, et al. (author)
  • The room temperature crystal structure of a bacterial phytochrome determined by serial femtosecond crystallography
  • 2016
  • In: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 6
  • Journal article (peer-reviewed)abstract
    • Phytochromes are a family of photoreceptors that control light responses of plants, fungi and bacteria. A sequence of structural changes, which is not yet fully understood, leads to activation of an output domain. Time-resolved serial femtosecond crystallography (SFX) can potentially shine light on these conformational changes. Here we report the room temperature crystal structure of the chromophore-binding domains of the Deinococcus radiodurans phytochrome at 2.1 angstrom resolution. The structure was obtained by serial femtosecond X-ray crystallography from microcrystals at an X-ray free electron laser. We find overall good agreement compared to a crystal structure at 1.35 angstrom resolution derived from conventional crystallography at cryogenic temperatures, which we also report here. The thioether linkage between chromophore and protein is subject to positional ambiguity at the synchrotron, but is fully resolved with SFX. The study paves the way for time-resolved structural investigations of the phytochrome photocycle with time-resolved SFX.
  •  
12.
  • Giritli Nygren, Katarina, 1971-, et al. (author)
  • Thoughts about intersectionality and risk. Interviews with key scholar
  • 2024
  • In: Journal of Risk Research. - : Routledge. - 1366-9877 .- 1466-4461.
  • Journal article (peer-reviewed)abstract
    • Since the early twenty first century, feminist and intersectional approaches to risk research have gained momentum, initially emerging from studies on HIV risks within health studies. Over the past decade, these approaches have expanded to other fields. As editors of this special issue, Katarina Giritli Nygren and Anna Olofsson introduce a reflection piece anchoring the issue. The reflection piece includes insights from seven influential scholars in the intersectionality, equality, and risk fields: Lisa Bowleg, Dean Curran, Kelly Hannah Moffat, Claudia Mitchell, Lori Peek, Ignacio Rubio C., and Jens O. Zinn. Each scholar offers personal reflections on the development of intersectional analyses in risk research, highlighting key areas for future research. Three themes emerged: challenging risk as a neutral concept, addressing the complexity of risks in everyday life, and navigating between social structures and identity struggles. Contributors argue for contextualising risk within broader societal structures, embracing complexity, and understanding the intertwined nature of inequalities. Some, but not all, also advocate for intersectionality as a critical concept for studies of systemic change and equality. Overall, the reflections underscore the importance of centring intersectionality in understanding the dimensions of inequality and risk. The piece concludes by calling for further conversations and reflections to deepen our understanding of risk mobilisations and their links to inequality, both locally and globally. Such conversations can challenge assumptions and revitalize risk research, envisioning alternative worlds that prioritize equality.
  •  
13.
  • Misra, Shivani, et al. (author)
  • The case for precision medicine in the prevention, diagnosis, and treatment of cardiometabolic diseases in low-income and middle-income countries
  • 2023
  • In: The Lancet Diabetes and Endocrinology. - 2213-8587. ; 11:11, s. 836-847
  • Research review (peer-reviewed)abstract
    • Cardiometabolic diseases are the leading preventable causes of death in most geographies. The causes, clinical presentations, and pathogenesis of cardiometabolic diseases vary greatly worldwide, as do the resources and strategies needed to prevent and treat them. Therefore, there is no single solution and health care should be optimised, if not to the individual (ie, personalised health care), then at least to population subgroups (ie, precision medicine). This optimisation should involve tailoring health care to individual disease characteristics according to ethnicity, biology, behaviour, environment, and subjective person-level characteristics. The capacity and availability of local resources and infrastructures should also be considered. Evidence needed for equitable precision medicine cannot be generated without adequate data from all target populations, and the idea that research done in high-income countries will transfer adequately to low-income and middle-income countries (LMICs) is problematic, as many migration studies and transethnic comparisons have shown. However, most data for precision medicine research are derived from people of European ancestry living in high-income countries. In this Series paper, we discuss the case for precision medicine for cardiometabolic diseases in LMICs, the barriers and enablers, and key considerations for implementation. We focus on three propositions: first, failure to explore and implement precision medicine for cardiometabolic disease in LMICs will enhance global health disparities. Second, some LMICs might already be placed to implement cardiometabolic precision medicine under appropriate circumstances, owing to progress made in treating infectious diseases. Third, improvements in population health from precision medicine are most probably asymptotic; the greatest gains are more likely to be obtained in countries where health-care systems are less developed. We outline key recommendations for implementation of precision medicine approaches in LMICs.
  •  
14.
  • Norris, Shane A., et al. (author)
  • Understanding and acting on the developmental origins of health and disease in Africa would improve health across generations
  • 2017
  • In: Global Health Action. - : TAYLOR & FRANCIS LTD. - 1654-9716 .- 1654-9880. ; 10:1
  • Journal article (peer-reviewed)abstract
    • Data from many high- and low- or middle-income countries have linked exposures during key developmental periods (in particular pregnancy and infancy) to later health and disease. Africa faces substantial challenges with persisting infectious disease and now burgeoning non-communicable disease. This paper opens the debate to the value of strengthening the developmental origins of health and disease (DOHaD) research focus in Africa to tackle critical public health challenges across the life-course. We argue that the application of DOHaD science in Africa to advance life-course prevention programmes can aid the achievement of the Sustainable Development Goals, and assist in improving health across generations. To increase DOHaD research and its application in Africa, we need to mobilise multisectoral partners, utilise existing data and expertise on the continent, and foster a new generation of young African scientists engrossed in DOHaD.
  •  
15.
  • Pablo, H., et al. (author)
  • epsilon Lupi : measuring the heartbeat of a doubly magnetic massive binary with BRITE Constellation
  • 2019
  • In: Monthly notices of the Royal Astronomical Society. - : OXFORD UNIV PRESS. - 0035-8711 .- 1365-2966. ; 488:1, s. 64-77
  • Journal article (peer-reviewed)abstract
    • epsilon Lupi A is a binary system consisting of two main-sequence early B-type stars Aa and Ab in a short period, moderately eccentric orbit. The close binary pair is the only doubly magnetic massive binary currently known. Using photometric data from the BRITE Constellation we identify a modest heartbeat variation. Combining the photometry with radial velocities of both components we determine a full orbital solution including empirical masses and radii. These results are compared with stellar evolution models as well as interferometry and the differences discussed. We also find additional photometric variability at several frequencies, finding it unlikely these frequencies can be caused by tidally excited oscillations. We do, however, determine that these signals are consistent with gravity mode pulsations typical for slowly pulsating B stars. Finally we discuss how the evolution of this system will be affected by magnetism, determining that tidal interactions will still be dominant.
  •  
16.
  • Perez, Carlos Herrera, et al. (author)
  • Emotions as a bridge to the environment : On the role of body in organisms and robots
  • 2006
  • In: From Animals to Animats 9. - Berlin, Heidelberg : Springer. - 9783540386087 - 9783540386155 ; , s. 3-16
  • Conference paper (peer-reviewed)abstract
    • Adaptive agents exhibit tightly coupled interactions between nervous system, body and environment. Parisi recently suggested that the current focus on sensorimotor interaction between agent and environment needs to be complemented by an "internal robotics", i.e. modeling of the interaction between internal physiology and nervous system in, for example, emotional mechanisms. The dynamical systems notion of "collective variables" can help understanding such interactions. In emotions physiological states are key parameters that trace the global dynamic concern relevance of the situation. Such variables may be key, in adaptive systems, to monitoring and controlling the agent's interaction with the external environment. We show in a simple robotic simulation that the neural controller can self-organize to exploit the dynamical regularities traced by these variables. We conclude this can prove to be a useful technique in robots and animals, towards evolving emotion-based adaptive behaviors.
  •  
17.
  • Ravanfar, P, et al. (author)
  • In Vivo 7-Tesla MRI Investigation of Brain Iron and Its Metabolic Correlates in Chronic Schizophrenia
  • 2022
  • In: Schizophrenia (Heidelberg, Germany). - : Springer Science and Business Media LLC. - 2754-6993. ; 8:1, s. 86-
  • Journal article (peer-reviewed)abstract
    • Brain iron is central to dopaminergic neurotransmission, a key component in schizophrenia pathology. Iron can also generate oxidative stress, which is one proposed mechanism for gray matter volume reduction in schizophrenia. The role of brain iron in schizophrenia and its potential link to oxidative stress has not been previously examined. In this study, we used 7-Tesla MRI quantitative susceptibility mapping (QSM), magnetic resonance spectroscopy (MRS), and structural T1 imaging in 12 individuals with chronic schizophrenia and 14 healthy age-matched controls. In schizophrenia, there were higher QSM values in bilateral putamen and higher concentrations of phosphocreatine and lactate in caudal anterior cingulate cortex (caCC). Network-based correlation analysis of QSM across corticostriatal pathways as well as the correlation between QSM, MRS, and volume, showed distinct patterns between groups. This study introduces increased iron in the putamen in schizophrenia in addition to network-wide disturbances of iron and metabolic status.
  •  
18.
  •  
19.
  • Rosenblad, C, et al. (author)
  • Protection and regeneration of nigral dopaminergic neurons by neurturin or GDNF in a partial lesion model of Parkinson's disease after administration into the striatum or the lateral ventricle
  • 1999
  • In: European Journal of Neuroscience. - 1460-9568. ; 11:5, s. 1554-1566
  • Journal article (peer-reviewed)abstract
    • Both glial cell line-derived neurotrophic factor (GDNF) and its recently discovered congener, neurturin (NTN), have been shown to exert neuroprotective effects on lesioned nigral dopamine (DA) neurons when administered at the level of the substantia nigra. In the present study, we have explored the relative in vivo potency of these two neurotrophic factors using two alternative routes of administration, into the striatum or the lateral ventricle, which may be more relevant in a clinical setting. In rats subjected to an intrastriatal (IS) 6-hydroxydopamine (6-OHDA) lesion, GDNF and NTN were injected every third day for 3 weeks starting on the day after the 6-OHDA injection. GDNF provided almost complete (90-92%) protection of the lesioned nigral DA neurons after both IS and intracerebroventricular (ICV) administration. NTN, by contrast, was only partially effective after IS injection (72% sparing) and totally ineffective after ICV injection. Although the trophic factor injections protected the nigral neurons from lesion-induced cell death, the level of expression of the phenotypic marker, tyrosine hydroxylase (TH), was markedly reduced in the rescued cell bodies. The extent of 6-OHDA-induced DA denervation in the striatum was unaffected by both types of treatment; consistent with this observation, the high rate of amphetamine-induced turning seen in the lesioned control animals was unaltered by either GDNF or NTN treatment. In the GDNF-treated animals, and to a lesser extent also after IS NTN treatment, prominent axonal sprouting was observed within the globus pallidus, at the level where the lesioned nigrostriatal axons are known to end at the time of onset of the neurotrophic factor treatment. The results show that GDNF is highly effective as a neuroprotective and axon growth-stimulating agent in the IS 6-OHDA lesion model after both IS and ICV administration. The lower efficacy of NTN after IS, and particularly ICV, administration may be explained by the poor solubility and diffusion properties at neutral pH.
  •  
20.
  • Zwintz, K., et al. (author)
  • beta Cas : The first ffi Scuti star with a dynamo magnetic field
  • 2020
  • In: Astronomy and Astrophysics. - : EDP SCIENCES S A. - 0004-6361 .- 1432-0746. ; 643
  • Journal article (peer-reviewed)abstract
    • Context. F-type stars are characterised by several physical processes such as different pulsation mechanisms, rotation, convection, diffusion, and magnetic fields. The rapidly rotating delta Scuti star beta Cas can be considered as a benchmark star to study the interaction of several of these effects.Aims. We investigate the pulsational and magnetic field properties of beta Cas. We also determine the star's apparent fundamental parameters and chemical abundances.Methods. Based on photometric time series obtained from three different space missions (BRITE-Constellation, SMEI, and TESS), we conduct a frequency analysis and investigate the stability of the pulsation amplitudes over four years of observations. We investigate the presence of a magnetic field and its properties using spectropolarimetric observations taken with the Narval instrument by applying the least-squares deconvolution and Zeeman-Doppler imaging techniques.Results. The star beta Cas shows only three independent p-mode frequencies down to the few ppm-level; its highest amplitude frequency is suggested to be an n=3, l=2, m=0 mode. Its magnetic field structure is quite complex and almost certainly of a dynamo origin. The atmosphere of beta Cas is slightly deficient in iron peak elements and slightly overabundant in C, O, and heavier elements.Conclusions. Atypically for delta Scuti stars, we can only detect three pulsation modes down to exceptionally low noise levels for beta Cas. The star is also one of very few delta Scuti pulsators known to date to show a measurable magnetic field and the first delta Scuti star with a dynamo magnetic field. These characteristics make beta Cas an interesting target for future studies of dynamo processes in the thin convective envelopes of F-type stars, the transition region between fossil and dynamo fields, and the interaction between pulsations and magnetic field.
  •  
Skapa referenser, mejla, bekava och länka
  • Result 1-20 of 20

Kungliga biblioteket hanterar dina personuppgifter i enlighet med EU:s dataskyddsförordning (2018), GDPR. Läs mer om hur det funkar här.
Så här hanterar KB dina uppgifter vid användning av denna tjänst.

 
pil uppåt Close

Copy and save the link in order to return to this view