1. |
- Behar, Etienne, et al.
(author)
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Mass-loading of the solar wind at 67P/Churyumov-Gerasimenko : Observations and modelling
- 2016
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In: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 596
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Journal article (peer-reviewed)abstract
- Context. The first long-term in-situ observation of the plasma environment in the vicinity of a comet, as provided by the European Rosetta spacecraft.Aims. Here we offer characterisation of the solar wind flow near 67P/Churyumov-Gerasimenko (67P) and its long term evolution during low nucleus activity. We also aim to quantify and interpret the deflection and deceleration of the flow expected from ionization of neutral cometary particles within the undisturbed solar wind.Methods. We have analysed in situ ion and magnetic field data and combined this with hybrid modeling of the interaction between the solar wind and the comet atmosphere.Results. The solar wind deflection is increasing with decreasing heliocentric distances, and exhibits very little deceleration. This is seen both in observations and in modeled solar wind protons. According to our model, energy and momentum are transferred from the solar wind to the coma in a single region, centered on the nucleus, with a size in the order of 1000 km. This interaction affects, over larger scales, the downstream modeled solar wind flow. The energy gained by the cometary ions is a small fraction of the energy available in the solar wind.Conclusions. The deflection of the solar wind is the strongest and clearest signature of the mass-loading for a small, low-activity comet, whereas there is little deceleration of the solar wind.
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2. |
- Behar, Etienne, et al.
(author)
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Solar wind dynamics around a comet : A 2D semi-analytical kinetic model
- 2018
-
In: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 620
-
Journal article (peer-reviewed)abstract
- Aims.We aim at analytically modelling the solar wind proton trajectories during their interaction with a partially ionised cometaryatmosphere, not in terms of bulk properties of the flow but in terms of single particle dynamics.Methods.We first derive a generalised gyromotion, in which the electric field is reduced to its motional component. Steady-stateis assumed, and simplified models of the cometary density and of the electron fluid are used to express the force experienced byindividual solar wind protons during the interaction.Results.A three-dimensional (3D) analytical expression of the gyration of two interacting plasma beams is obtained. Applying it to acomet case, the force on protons is always perpendicular to their velocity and has an amplitude proportional to 1/r2. The solar winddeflection is obtained at any point in space. The resulting picture presents a caustic of intersecting trajectories, and a circular regionis found that is completely free of particles. The particles do not lose any kinetic energy and this absence of deceleration, togetherwith the solar wind deflection pattern and the presence of a solar wind ion cavity, is in good agreement with the general results of theRosettamission.Conclusions.The qualitative match between the model and thein situdata highlights how dominant the motional electric field isthroughout most of the interaction region for the solar wind proton dynamics. The model provides a simple general kinetic descriptionof how momentum is transferred between these two collisionless plasmas. It also shows the potential of this semi-analytical modelfor a systematic quantitative comparison to the data.
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3. |
- Bengtsson, Caroline, et al.
(author)
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Chronic rhinosinusitis impairs sleep quality : results of the GA(2)LEN study
- 2017
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In: Sleep. - : Oxford University Press. - 0161-8105 .- 1550-9109. ; 40:1
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Journal article (peer-reviewed)abstract
- STUDY OBJECTIVES: To analyse the prevalence of sleep problems in subjects with CRS and to determine whether the disease severity of CRS affects sleep quality.METHODS: Questionnaires were sent to a random sample of 45 000 adults in four Swedish cities. Questions on CRS, asthma, allergic rhinitis, co-morbidities, tobacco use, educational level and physical activity were included. CRS was defined according to the European Position Paper on Rhinosinusitis and Nasal Polyps (EPOS) epidemiological criteria. The disease severity of CRS was defined by the number of reported CRS symptoms. Sleep quality was assessed using the Basic Nordic Sleep Questionnaire.RESULTS: Of the 26 647 subjects, 2249 (8.4%) had CRS. Reported sleep problems were 50-90% more common among subjects with CRS compared with those without or the total population. The prevalence of reported sleep problems increased in conjunction with the severity of CRS. After adjusting for gender, BMI, age, tobacco use, asthma, somatic diseases, physical activity level and educational level, participants with four symptoms of CRS (compared with subjects without CRS symptoms) displayed a higher risk of snoring (adj. OR (95% CI): 3.13 (2.22-4.41)), difficulties inducing sleep (3.98 (2.94-5.40)), difficulties maintaining sleep (3.44 (2.55-4.64)), early morning awakening (4.71 (3.47-6.38)) and excessive daytime sleepiness (4.56 (3.36-6.18)). The addition of persistent allergic rhinitis to CRS further increased the risk of sleep problems.CONCLUSIONS: Sleep problems are highly prevalent among subjects with CRS. The disease severity of CRS negatively affects sleep quality.
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4. |
- Bengtsson, Caroline, et al.
(author)
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Impact of nasal obstruction on sleep quality : a community-based study of women
- 2015
-
In: European Archives of Oto-Rhino-Laryngology. - : Springer Science and Business Media LLC. - 0937-4477 .- 1434-4726. ; 272:1, s. 97-103
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Journal article (peer-reviewed)abstract
- The aim of the study was to analyse the impact of self-reported nasal obstruction on sleep quality in women. A community-based sample of 400 women underwent a full night of polysomnography. Airway diseases, allergies and sleep-related symptoms were assessed by questionnaires. Women with subjective nasal obstruction were subdivided into three groups: persistent nasal obstruction (PNO, n = 46), hay fever (n = 88) and nasal obstruction at night (NON, n = 30). Sleep problems and related daytime symptoms were most prevalent among women with NON. After adjusting for age, BMI, smoking and asthma, NON was an independent predictor of 'Difficulties inducing sleep due to nasal obstruction' [adjusted odds ratio (95 % CI): 89.5 (27.0-296.7)], 'Snoring' [4.2 (1.7-10.2)], 'Sweating at night' [2.6 (1.1-6.1)], 'Difficulties maintaining sleep' [2.7 (1.2-6.2)], and 'Waking up hastily gasping for breath' [32.2 (8.7-119.1)]. 'Dry mouth on awakening' [7.7 (3.2-18.4)], 'Waking up unrefreshed' [2.7 (1.2-6.0)], 'Excessive daytime sleepiness' [2.6 (1.1-6.0)], and 'Daytime nasal obstruction' [12.2 (4.8-31.2)] were also associated with NON. Persistent nasal obstruction and hay fever were both associated with some reported sleep problems due to an overlap with NON. When women with NON were excluded, only 'Daytime nasal obstruction' was still significantly associated with PNO, while hay fever was associated with 'Daytime nasal obstruction' and 'Waking up hastily gasping for breath'. There were no significant differences in objectively measured sleep variables between any of the three subgroups and the study cohort. Self-reported nasal obstruction at night in women has a significant effect on several subjective day- and nighttime symptoms, but it does not appear to affect objectively measured sleep quality.
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5. |
- Bjermer, Leif, et al.
(author)
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The complex pathophysiology of allergic rhinitis : Scientific rationale for the development of an alternative treatment option
- 2019
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In: Allergy, Asthma and Clinical Immunology. - : Springer Science and Business Media LLC. - 1710-1492. ; 15, s. 24-
-
Research review (peer-reviewed)abstract
- Allergic rhinitis (AR) poses a global health problem and can be challenging to treat. Many of the current symptomatic treatments for AR have been available for decades, yet there has been little improvement in patient quality of life or symptom burden over the years. In this review, we ask why this might be and explore the pathophysiological gaps that exist within the various AR treatment classes. We focus on the benefits and drawbacks of different treatment options and delivery routes for AR treatments and consider how, given what is known about AR pathophysiology and symptomatology, patients may be offered more effective treatment options for rapid, effective, and sustained AR control. In particular, we consider how a new AR preparation, MP-AzeFlu (Dymista ® , Meda, Sweden), comprising a formulation of an intranasal antihistamine (azelastine hydrochloride), an intranasal corticosteroid (fluticasone propionate), and excipients delivered in a single spray, may offer benefits over and above single and multiple AR therapy options. We review the evidence in support of this treatment across the spectrum of AR disease. The concept of AR control is also reviewed within the context of new European Union and Contre les Maladies Chroniques pour un VIeillissement Actif-Allergic Rhinitis and its Impact on Asthma initiatives.
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6. |
- Chaplin, John, et al.
(author)
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Varför ska du använda PROMIS? : Nytt system för patientrapporterad utfallsmått
- 2018
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Conference paper (other academic/artistic)abstract
- PROMIS är ett itembanksystem för hälso- och sjukvården. Syftet är att erbjuda moderna, patientrapporterade mått som kan användas för flertalet patientgrupper till en mycket låg kostnad och med ett nationellt supportsystem.En itembankär en modern form av elektronisk enkät som kan innehålla ett stort antal enkätfrågor. Ett datorprogram väljer ut de mest lämpade frågorna till varje person utifrån dennes svar på föregående frågor, på så sätt enkäten individanpassas.
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7. |
- Ehnhage, Anders, et al.
(author)
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Treatment of idiopathic rhinitis with kinetic oscillations : a multi-centre randomized controlled study
- 2016
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In: Acta Oto-Laryngologica. - : Informa UK Limited. - 0001-6489 .- 1651-2251. ; 136:8, s. 852-859
-
Journal article (peer-reviewed)abstract
- Conclusions: The potential effects of KOS are still uncertain regarding the most effective air pressure to be used as well as the physiological effects on the nasal mucosa. The results of the study do not support a convincing treatment effect by KOS on IR.Objectives: Idiopathic rhinitis (IR) is a common disorder, affecting ∼10-20% of the population. A new method for treating IR, Kinetic Oscillation Stimulation (KOS), has been reported to have beneficial effects on total vasomotor symptom scores (TVRSS). The primary objective with this study was to evaluate if a mean pressure of 65 mbar, pressure amplitude of 100 mbar, and 68Hz treatment with KOS had a positive effect on total vasomotor symptom scores (TVRSS), as compared with a mean pressure of 65 mbar, pressure amplitude of 4 mbar, and 68Hz treatment in patients with idiopathic rhinitis.Methods: Two hundred and seven patients were randomized (Full Analysis Set, FAS) in the study, including five visits and lasting for approximate to 25 weeks. All patients had two treatment episodes, and all patients had at least one treatment, meant as active, with high amplitude pressure for 10min in each nostril. Group 1 had two such treatments, and Group 2 had one treatment with low amplitude pressure, initially meant as placebo, on one occasion. Because of numerical improvements in these two groups, a new control group, Group 3, was introduced. They had one new control treatment where the balloon was inserted into the nose, without any air inflation and without oscillations.Results: KOS treatment with high amplitude pressure did not have significant beneficial effects as compared to low amplitude pressure on TVRSS. Numerical improvements in TVRSS and SNOT 22 were found when comparing high and low amplitude pressure treatments with uninflated balloon treatment. However, this part of the study was initially single-blinded, and these results were secondary objectives.
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8. |
- Eriksson, Jenny, 1975-, et al.
(author)
-
New ways of collecting individual travel information : Evaluation of data collection and recruitment methods
- 2018
-
Reports (other academic/artistic)abstract
- The overall purpose of the project is to conduct a demonstration study that shows how two data collection methods that have been developed to collect travel survey data perform in the field, and how they perform compared with traditional TS (i.e., postal questionnaires and/or telephone interviews). The project is also intended to provide a better understanding of the ways in which different recruitment methods of respondents can be used so that future TS can be more cost effective.The two collection methods tested consist of a mobile app and an online questionnaire with a map to assist the respondents to identify travel destinations. Three recruitment methods were used, i.e., recruitment via random sampling, a web panel, and crowdsourcing. The portion of the random sample that received an online questionnaire was divided into two groups. Half the group was given no incentive, while the other half received a gift card worth SEK 100 after answering the questioner. Those who were recruited via a web panel and were to use the mobile app were rewarded in the form of a gift card worth SEK 100 if, at minimum, they made corrections to trips made on one day registered in the mobile app. A nonresponse analysis was performed of the random sample for both the online questionnaire and the mobile app. Cost estimates for each collection method and recruitment method were also performed, as were uncertainty estimates.Overall, the study shows that the mobile app registered significantly more trips per respondent than did the online questionnaire, while the distances travelled were comparable. There are several possible interpretations of this. One is that people who responded to the online questionnaire either forget about and/or combined short trips (particularly trips made for the purposes of leisure or shopping, and using the travel modes walking and car). One presumable explanation for this is that it is easier to confirm/correct the trips that the mobile app suggests than it is to recall and enter all trips in an online questionnaire. Another possible interpretation is that people responding to different data collection methods have different travel patterns. Yet another explanation is connected to technique issues regarding the different data collection methods.
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9. |
- Eriksson, Jenny, 1975-, et al.
(author)
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Nya sätt att samla in individuell resvaneinformation : Utvärdering av insamlings- och rekryteringsmetoder
- 2018
-
Reports (other academic/artistic)abstract
- Inom samverkansprogrammet Nästa generations resor och transporter, som Trafikanalys är huvudansvarig för, har man identifierat ett behov av att finna och utveckla nya lösningar för resvaneundersökningar (RVU:er). Bakgrunden till detta är bland annat sjunkande svarsfrekvenser med dagens metoder, vilket skulle kunna ge problem med representativiteten. Det anses som mycket angeläget att utveckla nya metoder för datainsamling för framtidens RVU:er, både på kort och lång sikt.Det övergripande syftet med projektet är att göra en demonstrationsstudie som visar hur två datainsamlingsmetoder som har utvecklats för att samla in resevaneundersökningsdata presterar i fält, samt hur de presterar jämfört med ”traditionell” RVU (postal enkät och/eller telefonintervjuer). Projektet syftar också till att få bättre förståelse för hur olika rekryteringsmetoder kan användas för att framtida RVU:er ska kunna bli mer kostnadseffektiva. De två insamlingsmetoder som testats är webbenkät med karta och mobilapp. Tre rekryteringsmetoder har använts och dessa är rekrytering via slumpmässigt urval, webbpanel och crowdsourcing.
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10. |
- Fatemi, Shahab, et al.
(author)
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A modelling approach to infer the solar wind dynamic pressure from magnetic field observations inside Mercury's magnetosphere
- 2018
-
In: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 614
-
Journal article (peer-reviewed)abstract
- Aims: The lack of an upstream solar wind plasma monitor when a spacecraft is inside the highly dynamic magnetosphere of Mercury limits interpretations of observed magnetospheric phenomena and their correlations with upstream solar wind variations.Methods: We used AMITIS, a three-dimensional GPU-based hybrid model of plasma (particle ions and fluid electrons) to infer the solar wind dynamic pressure and Alfvén Mach number upstream of Mercury by comparing our simulation results with MESSENGER magnetic field observations inside the magnetosphere of Mercury. We selected a few orbits of MESSENGER that have been analysed and compared with hybrid simulations before. Then we ran a number of simulations for each orbit (~30–50 runs) and examined the effects of the upstream solar wind plasma variations on the magnetic fields observed along the trajectory of MESSENGER to find the best agreement between our simulations and observations.Results: We show that, on average, the solar wind dynamic pressure for the selected orbits is slightly lower than the typical estimated dynamic pressure near the orbit of Mercury. However, we show that there is a good agreement between our hybrid simulation results and MESSENGER observations for our estimated solar wind parameters. We also compare the solar wind dynamic pressure inferred from our model with those predicted previously by the WSA-ENLIL model upstream of Mercury, and discuss the agreements and disagreements between the two model predictions. We show that the magnetosphere of Mercury is highly dynamic and controlled by the solar wind plasma and interplanetary magnetic field. In addition, in agreement with previous observations, our simulations show that there are quasi-trapped particles and a partial ring current-like structure in the nightside magnetosphere of Mercury, more evident during a northward interplanetary magnetic field (IMF). We also use our simulations to examine the correlation between the solar wind dynamic pressure and stand-off distance of the magnetopause and compare it with MESSENGER observations. We show that our model results are in good agreement with the response of the magnetopause to the solar wind dynamic pressure, even during extreme solar events. We also show that our model can be used as a virtual solar wind monitor near the orbit of Mercury and this has important implications for interpretation of observations by MESSENGER and the future ESA/JAXA mission to Mercury, BepiColombo.
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11. |
- Felton, Adam, et al.
(author)
-
Replacing monocultures with mixed-species : Ecosystem service implications of two production forest alternatives in Sweden
- 2016
-
In: Ambio. - : Springer Science and Business Media LLC. - 0044-7447 .- 1654-7209. ; 45:Suppl. 2, s. 124-139
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Journal article (peer-reviewed)abstract
- Whereas there is evidence that mixed-species approaches to production forestry in general can provide positive outcomes relative to monocultures, it is less clear to what extent multiple benefits can be derived from specific mixed-species alternatives. To provide such insights requires evaluations of an encompassing suite of ecosystem services, biodiversity, and forest management considerations provided by specific mixtures and monocultures within a region. Here, we conduct such an assessment in Sweden by contrasting even-aged Norway spruce (Picea abies)-dominated stands, with mixed-species stands of spruce and birch (Betula pendula or B. pubescens), or spruce and Scots pine (Pinus sylvestris). By synthesizing the available evidence, we identify positive outcomes from mixtures including increased biodiversity, water quality, esthetic and recreational values, as well as reduced stand vulnerability to pest and pathogen damage. However, some uncertainties and risks were projected to increase, highlighting the importance of conducting comprehensive interdisciplinary evaluations when assessing the pros and cons of mixtures.
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12. |
- Felton, Adam, et al.
(author)
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Replacing monocultures with mixed-species stands : Ecosystem service implications of two production forest alternatives in Sweden
- 2016
-
In: Ambio. - : Springer Science and Business Media LLC. - 0044-7447 .- 1654-7209. ; 45, s. 124-139
-
Journal article (peer-reviewed)abstract
- Whereas there is evidence that mixed-species approaches to production forestry in general can provide positive outcomes relative to monocultures, it is less clear to what extent multiple benefits can be derived from specific mixed-species alternatives. To provide such insights requires evaluations of an encompassing suite of ecosystem services, biodiversity, and forest management considerations provided by specific mixtures and monocultures within a region. Here, we conduct such an assessment in Sweden by contrasting even-aged Norway spruce (Picea abies)-dominated stands, with mixed-species stands of spruce and birch (Betula pendula or B. pubescens), or spruce and Scots pine (Pinus sylvestris). By synthesizing the available evidence, we identify positive outcomes from mixtures including increased biodiversity, water quality, esthetic and recreational values, as well as reduced stand vulnerability to pest and pathogen damage. However, some uncertainties and risks were projected to increase, highlighting the importance of conducting comprehensive interdisciplinary evaluations when assessing the pros and cons of mixtures.
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13. |
- Gunell, Herbert, et al.
(author)
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The infant bow shock : a new frontier at a weak activity comet
- 2018
-
In: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 619
-
Journal article (peer-reviewed)abstract
- The bow shock is the first boundary the solar wind encounters as it approaches planets or comets. The Rosetta spacecraft was able to observe the formation of a bow shock by following comet 67P/Churyumov-Gerasimenko toward the Sun, through perihelion, and back outward again. The spacecraft crossed the newly formed bow shock several times during two periods a few months before and after perihelion; it observed an increase in magnetic field magnitude and oscillation amplitude, electron and proton heating at the shock, and the diminution of the solar wind further downstream. Rosetta observed a cometary bow shock in its infancy, a stage in its development not previously accessible to in situ measurements at comets and planets.
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14. |
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15. |
- Holmström Lind, Christine, 1969-, et al.
(author)
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MNC involvement in social innovations : the issue of knowledge, networks and power
- 2018
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In: Critical Perspectives on International Business. - : Emerald. - 1742-2043 .- 1758-6062. ; 16:1, s. 79-99
-
Journal article (peer-reviewed)abstract
- PurposeThis paper aims to develop a conceptual framework and presents a number of propositions relating to why and how multinational companies (MNCs) engage in social innovations. The central focus is on the role of MNC knowledge, networks and power for their involvement in social innovations.Design/methodology/approachThe authors combine literature on social innovations, business innovations and MNC literature, and present a number of propositions dealing with the link between MNC knowledge, networks and power-relations and their potential involvement in social innovations.FindingsThe authors emphasize that when social innovations are embraced by MNCs, the way that these corporations use their knowledge, networks and existing power-relations needs to be adapted to the new conditions present in the social innovation arena.Research limitations/implicationsThe main limitation of this work is that the propositions are based on anecdotal evidence and that they are restricted to literature revolving around a few theoretical concepts (knowledge, networks, power). Against this, the authors suggest that to address the call for more empirical work on MNCs engagement in social innovation, these concepts could be used as a starting point in future empirical investigations.Originality/valueThe paper brings together and outlines a theoretical framework based on three theoretical approaches to the MNC as suggested by the literature: the knowledge-based MNC, differentiated MNC and political MNC. Based on these three perspectives, the key contribution of this paper is to develop a broader understanding of why and how MNCs engage in social innovation and the potential underlying liabilities for this involvement.
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16. |
- Holmström, Mats, et al.
(author)
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Allergisk rinit drabbar en tredjedel av befolkningen: Individualiserad behandling viktig för att uppnå symtomfrihet
- 2016
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In: Läkartidningen. - Stockholm : Läkartidningen förlag AB. - 0023-7205 .- 1652-7518. ; 113:14, s. 1-5
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Journal article (peer-reviewed)abstract
- Allergic rhinitis is the most common form of allergy with a prevalence of 30%. Allergic rhinitis is associated with substantial health economic costs and patient suffering. Asthma is strongly associated with allergic rhinitis. The treatment of allergic rhinitis should be individualized and include the whole airway. The treatment goals should be a patient free of symptoms affecting their daily life or sleep. © 2016, Swedish Medical Association. All rights reserved.
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17. |
- Häggström, Marie, PhD, 1967-, et al.
(author)
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Establishing Patient Safety in Intensive Care -A Grounded Theory. : Building Trust-Important for Patient Safety
- 2017
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In: Open Journal of Nursing. - : Scientific Research Publishing, Inc.. - 2162-5336 .- 2162-5344. ; 07:10
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Journal article (peer-reviewed)abstract
- Background: The modern intensive care unit (ICU) is a complex and high-risk environment, and even small adverse events and changes may deteriorate the patient’s conditions and eventually cause harm. Many factors can potentially be associated within an increased amount of errors, leading to adverse events. Nurses, nurse managers, and other leaders all play important roles in establishing patient safety. Aim: This study aimed to obtain a deeper understanding of leaders’ and nurses’ main concerns in establishing patient safety in Swedish intensive care units. Method: A grounded theory methodology was used. Data from 15 interviews with leaders and nurses involved in critical care in Sweden were collected, analysed and constant compared. Findings: The main concern in establishing patient safety was promoting quality of care, work engagement, and staffs well-being in strained ICUs. The core category building trust explained how the leaders’ and nurses’ strove for quality of care and wished a healthy, safe work environment. This is further explained in the categories “Being an accessible and able leader”, “Creating knowledge and understanding”, and “Establishing collaborative practice”. Conclusion: Establishing patient safety in the ICU requires that staffs enjoy going to work, have good work relations, are committed and want to stay at the unit. A healthy, salutogenetic unit with a work environment marked by trust provides a better opportunity to establish patient safety, and various leaders have potential to achieve this.
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18. |
- Kanstrup, Marie, et al.
(author)
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A Clinical Pilot Study of Individual and Group Treatment for Adolescents with Chronic Pain and Their Parents : Effects of Acceptance and Commitment Therapy on Functioning
- 2016
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In: Children. - : MDPI AG. - 2227-9067. ; 3:4
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Journal article (peer-reviewed)abstract
- Pediatric chronic pain is common and can result in substantial long-term disability. Previous studies on acceptance and commitment therapy (ACT) have shown promising results in improving functioning in affected children, but more research is still urgently needed. In the current clinical pilot study, we evaluated an ACT-based interdisciplinary outpatient intervention (14 sessions), including a parent support program (four sessions). Adolescents were referred to the clinic if they experienced disabling chronic pain. They were then randomized, along with their parents, to receive group (n = 12) or individual (n = 18) treatment. Adolescent pain interference, pain reactivity, depression, functional disability, pain intensity and psychological flexibility, along with parent anxiety, depression, pain reactivity and psychological flexibility were assessed using self-reported questionnaires. There were no significant differences in outcomes between individual and group treatment. Analyses illustrated significant (p < 0.01) improvements (medium to large effects) in pain interference, depression, pain reactivity and psychological flexibility post-treatment. Additionally, analyses showed significant (p < 0.01) improvements (large effects) in parent pain reactivity and psychological flexibility post-treatment. On all significant outcomes, clinically-significant changes were observed for 21%-63% of the adolescents across the different outcome measures and in 54%-76% of the parents. These results support previous findings and thus warrant the need for larger, randomized clinical trials evaluating the relative utility of individual and group treatment and the effects of parental interventions.
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19. |
- Khurana, Krishan K., et al.
(author)
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The role of plasma slowdown in the generation of Rhea's Alfvén wings
- 2017
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In: Journal of Geophysical Research - Space Physics. - 2169-9380 .- 2169-9402. ; 122:2, s. 1778-1788
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Journal article (peer-reviewed)abstract
- Alfvén wings are known to form when a conducting or mass-loading object slows down a flowing plasma in its vicinity. Alfvén wings are not expected to be generated when an inert moon such as Rhea interacts with Saturn's magnetosphere, where the plasma impacting the moon is absorbed and the magnetic flux passes unimpeded through the moon. However, in two close polar passes of Rhea, Cassini clearly observed magnetic field signatures consistent with Alfvén wings. In addition, observations from a high-inclination flyby (Distance > 100 R Rh ) of Rhea on 3 June 2010 showed that the Alfvén wings continue to propagate away from Rhea even at this large distance. We have performed three-dimensional hybrid simulations of Rhea's interaction with Saturn's magnetosphere which show that the wake refilling process generates a plasma density gradient directed in the direction of corotating plasma. The resulting plasma pressure gradient exerts a force directed toward Rhea and slows down the plasma streaming into the wake along field lines. As on the same field lines, outside of the wake, the plasma continues to move close to its full speed, this differential motion of plasma bends the magnetic flux tubes, generating Alfvén wings in the wake. The current system excited by the Alfvén wings transfers momentum to the wake plasma extracting it from plasma outside the wake. Our work demonstrates that Alfvén wings can be excited even when a moon does not possess a conducting exosphere.
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20. |
- Lindkvist, Jesper, et al.
(author)
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Callisto plasma interactions : Hybrid modeling including induction by a subsurface ocean
- 2015
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In: Journal of Geophysical Research - Space Physics. - 2169-9380 .- 2169-9402. ; 120:6, s. 4877-4889
-
Journal article (peer-reviewed)abstract
- By using a hybrid plasma solver (ions as particles and electrons as a fluid), we have modeled the interaction between Callisto and Jupiter's magnetosphere for variable ambient plasma parameters. We compared the results with the magnetometer data from flybys (C3, C9, and C10) by the Galileo spacecraft. Modeling the interaction between Callisto and Jupiter's magnetosphere is important to establish the origin of the magnetic field perturbations observed by Galileo and thought to be related to a subsurface ocean. Using typical upstream magnetospheric plasma parameters and a magnetic dipole corresponding to the inductive response inside the moon, we show that the model results agree well with observations for the C3 and C9 flybys, but agrees poorly with the C10 flyby close to Callisto. The study does support the existence of a subsurface ocean at Callisto.
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21. |
- Lindkvist, Jesper, 1986-, et al.
(author)
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Ceres interaction with the solar wind
- 2017
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In: Geophysical Research Letters. - 0094-8276 .- 1944-8007. ; 44:5, s. 2070-2077
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Journal article (peer-reviewed)abstract
- The solar wind interaction with Ceres is studied for a high water vapor release from its surface using a hybrid model including photoionization. We use a water vapor production rate of 6 kg/s, thought to be due to subsurface sublimation, corresponding to a detection on 6 March 2013 by the Herschel Space Observatory. We present the general morphology of the plasma interactions, both close to Ceres and on a larger scale. Mass loading of water ions causes a magnetic pileup region in front of Ceres, where the solar wind deflects up to 15 ∘ and slows down by 15%. The global plasma interaction with Ceres is not greatly affected by the source location of water vapor nor on gravity, only on the production rate of water vapor. On a global scale, Ceres has a comet-like interaction with the solar wind with observable perturbations farther than 250 Ceres radii downstream of the body.
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22. |
- Lindkvist, Jesper, 1986-
(author)
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Plasma Interactions with Icy Bodies in the Solar System
- 2016
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Doctoral thesis (other academic/artistic)abstract
- Here I study the “plasma interactions with icy bodies in the solar system”, that is, my quest to understand the fundamental processes that govern such interactions. By using numerical modelling combined with in situ observations, one can infer the internal structure of icy bodies and their plasma environments.After a broad overview of the laws governing space plasmas a more detailed part follows. This contains the method on how to model the interaction between space plasmas and icy bodies. Numerical modelling of space plasmas is applied to the icy bodies Callisto (a satellite of Jupiter), the dwarf planet Ceres (located in the asteroid main belt) and the comet 67P/Churyumov-Gerasimenko.The time-varying magnetic field of Jupiter induces currents inside the electrically conducting moon Callisto. These create magnetic field perturbations thought to be related to conducting subsurface oceans. The flow of plasma in the vicinity of Callisto is greatly affected by these magnetic field perturbations. By using a hybrid plasma solver, the interaction has been modelled when including magnetic induction and agrees well with magnetometer data from flybys (C3 and C9) made by the Galileo spacecraft. The magnetic field configuration allows an inflow of ions onto Callisto’s surface in the central wake. Plasma that hits the surface knocks away matter (sputtering) and creates Callisto’s tenuous atmosphere.A long term study of solar wind protons as seen by the Rosetta spacecraft was conducted as the comet 67P/Churyumov-Gerasimenko approached the Sun. Here, extreme ultraviolet radiation from the Sun ionizes the neutral water of the comet’s coma. Newly produced water ions get picked up by the solar wind flow, and forces the solar wind protons to deflect due to conservation of momentum. This effect of mass-loading increases steadily as the comet draws closer to the Sun. The solar wind is deflected, but does not lose much energy. Hybrid modelling of the solar wind interaction with the coma agrees with the observations; the force acting to deflect the bulk of the solar wind plasma is greater than the force acting to slow it down.Ceres can have high outgassing of water vapour, according to observations by the Herschel Space Observatory in 2012 and 2013. There, two regions were identified as sources of water vapour. As Ceres rotates, so will the source regions. The plasma interaction close to Ceres depends greatly on the source location of water vapour, whereas far from Ceres it does not. On a global scale, Ceres has a comet-like interaction with the solar wind, where the solar wind is perturbed far downstream of Ceres.
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23. |
- Lyly-Yrjänäinena, Jouni, et al.
(author)
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Effects of combining product-centric control and direct digital manufacturing: The case of preparing customized hose assembly kits
- 2016
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In: Computers in Industry. - : Elsevier BV. - 0166-3615. ; 82, s. 82-94
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Journal article (peer-reviewed)abstract
- The case study presents the effects of combining product-centric control and direct digital manufacturing (DDM) in the preparation of customized assembly kits. The theoretical contribution of the paper is in describing a combinatorial innovation in operations and production management: how to use productcentriccontrol to make DDM highly efficient when there are many generic and partly generic production resources. Evidence is found of many beneficial outcomes such as waste reduction, simplified planning, and improved customer responsiveness for the case of preparing customized assembly kits for hydraulichoses.
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24. |
- Löfstedt, Håkan, 1963-, et al.
(author)
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Respiratory symptoms and lung function in relation to wood dust and monoterpene exposure in the wood pellet industry
- 2017
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In: Upsala Journal of Medical Sciences. - : Taylor & Francis. - 0300-9734 .- 2000-1967. ; 122:2, s. 78-84
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Journal article (peer-reviewed)abstract
- INTRODUCTION: Wood pellets are used as a source of renewable energy for heating purposes. Common exposures are wood dust and monoterpenes, which are known to be hazardous for the airways. The purpose of this study was to study the effect of occupational exposure on respiratory health in wood pellet workers.MATERIALS AND METHODS: Thirty-nine men working with wood pellet production at six plants were investigated with a questionnaire, medical examination, allergy screening, spirometry, and nasal peak expiratory flow (nasal PEF). Exposure to wood dust and monoterpenes was measured.RESULTS: The wood pellet workers reported a higher frequency of nasal symptoms, dry cough, and asthma medication compared to controls from the general population. There were no differences in nasal PEF between work and leisure time. A lower lung function than expected (vital capacity [VC], 95%; forced vital capacity in 1 second [FEV1], 96% of predicted) was noted, but no changes were noted during shifts. There was no correlation between lung function and years working in pellet production. Personal measurements of wood dust at work showed high concentrations (0.16-19 mg/m(3)), and exposure peaks when performing certain work tasks. Levels of monoterpenes were low (0.64-28 mg/m(3)). There was no association between exposure and acute lung function effects.CONCLUSIONS: In this study of wood pellet workers, high levels of wood dust were observed, and that may have influenced the airways negatively as the study group reported upper airway symptoms and dry cough more frequently than expected. The wood pellet workers had both a lower VC and FEV1 than expected. No cross-shift changes were found.
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25. |
- Morén, Staffan, et al.
(author)
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Speech in Adults Treated for Unilateral Cleft Lip and Palate : Long-Term Follow-Up After One- or Two-Stage Palate Repair
- 2017
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In: The Cleft Palate-Craniofacial Journal. - : SAGE Publications. - 1055-6656 .- 1545-1569. ; 54:6, s. 639-649
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Journal article (peer-reviewed)abstract
- OBJECTIVE: To evaluate speech in adults treated for unilateral cleft lip and palate with one-stage or two-stage palate closure and compare the speech of the patients with that of a noncleft control group.DESIGN: Cross-sectional study with long-term follow-up.PARTICIPANTS/SETTING: All unilateral cleft lip and palate patients born from 1960 to 1987 and treated at Uppsala University Hospital, Sweden, were invited (n = 109). Participation rate was 67% (n = 73) at a mean of 35 years after primary surgery. Forty-seven had been treated according to one-stage palate closure and 26 according to two-stage palate closure. Pharyngeal flap surgery had been performed in 11 of the 73 patients (15%). The noncleft control group consisted of 63 age-matched volunteers.MAIN OUTCOME MEASURE(S): Speech-language pathologists rated perceptual speech characteristics from blinded audio recordings.RESULTS: Among patients, seven (10%) presented with hypernasality, 12 (16%) had audible nasal emission and/or nasal turbulence, five (7%) had consonant production errors, one (2%) had glottal reinforcements/substitutions, and one (2%) had reduced intelligibility. Controls had no audible signs of velopharyngeal insufficiency and no quantifiable problems with the other speech production variables. No significant differences were identified between patients treated with one-stage and two-stage palate closure for any of the variables.CONCLUSIONS: The prevalence of speech outcome indicative of velopharyngeal insufficiency among adult patients treated for unilateral cleft lip and palate was low but higher compared with individuals without cleft. Whether palatal closure is performed in one or two stages does not seem to affect the speech outcome at a mean age of 35 years.
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26. |
- Morén, Staffan
(author)
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Unilateral Cleft Lip and Palate : Speech, Voice and Nasal Function in Adults
- 2018
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Doctoral thesis (other academic/artistic)abstract
- Cleft lip and palate (CLP) is the most common craniofacial malformation. Even after repair of the cleft there may be persistent symptoms affecting speech, voice, nasal breathing, dentition, appearance and quality of life. The aims of the thesis were to: (I) investigate subjective nasal function and nasal airway at clinical examination, (II) evaluate speech by perceptual evaluation, (III) assess voice quality by perceptual evaluation and acoustic analysis and (IV) compare ratings of speech by naïve listeners, speech-language pathologists (SLPs) and patients.All consecutive patients with complete unilateral CLP, born 1960-1987, and treated at Uppsala University Hospital were invited. A total of 83 (76%) (I) and 73 (67%) (II, III, IV) of the 109 eligible patients and non-cleft controls (n=63) participated. Patients had been treated in childhood with one- or two-stage palate closure. The participants underwent clinical examination, recording of speech and filled in questionnaires.The results showed that: (I) Patients earlier treated for UCLP suffer from more nasal symptoms than controls. However, nasal symptoms were not associated with clinical findings or method of palate closure. (II) Seven patients (10%) presented with hypernasality, 12 (16%) had audible nasal emission and/or nasal turbulence, five (7%) had consonant production errors, one (2%) had glottal reinforcements/substitutions, and one had reduced intelligibility. Controls had no quantifiable problems with speech. (III) Among patients, the mean values for the 12 perceptual voice variables on a visual analogue scale (0 = no abnormality, 100 = maximal abnormality) ranged between 1 and 22 and the mean for all was 6 mm. Voice variables were similar between patients and controls except “vocal fry”; this and total mean of all the perceptual voice variables were slightly lower among patients (p = 0.009 and p = 0.018 ). No clear association was found between velopharyngeal insufficiency and dysphonia. (IV). There were positive correlations between speech ratings by naïve listeners and SLPs (r =0.44 to 0.69, p always < 0.001, Spearman). The correlations between ratings of any of these groups and the patients’ self-ratings were weaker (r < 0.40). The patients were less satisfied with their speech and rated themselves to have more speech abnormalities than controls (p < 0.001). There were no statistically significant differences in any of the variables regarding speech, voice or nose between patients treated with one-stage and two-stage palate closure in any of the studies.This thesis shows that adults treated for unilateral CLP have more nasal symptoms and cleft related speech abnormalities compared to the controls, however the prevalence of speech abnormalities are relatively low. Voice quality is not affected. Speech quality is rated differently by naïve listeners, SLPs and patients.
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27. |
- Morén, Staffan, et al.
(author)
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Voice quality in adults treated for unilateral cleft lip and palate : Long-Term Follow-Up After One- or Two-Stage Palate Repair
- 2018
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In: The Cleft Palate-Craniofacial Journal. - : SAGE Publications. - 1055-6656 .- 1545-1569. ; 55:8, s. 1103-1114
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Journal article (peer-reviewed)abstract
- Objectives: The aim of the current study was to assess voice quality among adults treated for unilateral cleft lip and palate (UCLP), after 1- or 2-stage palate closure, and compare it to a noncleft control group.Study Design: Cross-sectional study in UCLP patients with long-term follow-up and noncleft controls.Participants: UCLP patients born 1960-1987, treated at Uppsala University Hospital, Sweden, were examined (n = 73) at a mean of 35 years after primary surgery. Forty-seven patients (64%) had been treated with 1-stage palate closure and 26 with 2-stage closure (36%). The noncleft control group consisted of 63 age-matched volunteers.Main Outcome Measure(s): Ratings of perceptual voice characteristics from blinded voice recordings with Swedish Voice Evaluation Approach (SVEA) method. Acoustic voice analysis including pitch and spectral measures.Results: Among the patients, the mean values for the 12 evaluated variables on a VAS scale (0 = no abnormality, 100 = maximal abnormality) ranged between 1 and 22 and the mean for all was 6 mm. Voice variables were similar between patients and controls except the total mean of all the perceptual voice variables, as well as “vocal fry”—both slightly lower among patients (P = .018 and P = .009). There was no difference in any variable between patients treated with 1-stage and 2-stage palate closure. No clear relationship was found between VPI and dysphonia.Conclusion: The voice characteristics among adults treated for UCLP in childhood are not different from those of individuals without cleft.
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28. |
- Peroz, Roshan, et al.
(author)
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Can objective measurements of the nasal form and function represent the clinical picture in unilateral cleft lip and palate?
- 2017
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In: Journal of Plastic, Reconstructive & Aesthetic Surgery. - : Elsevier. - 1748-6815 .- 1878-0539. ; 70:5, s. 653-658
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Journal article (peer-reviewed)abstract
- Background: The present study aimed to evaluate the potential correlations between objective measurements of nasal function and self-assessed nasal symptoms or clinical findings at nasal examination among adults treated for unilateral cleft lip and palate (UCLP), respectively. Methods: All UCLP patients born between 1960 and 1987 (n = 109) treated at a tertiary referring center were invited. Participation rate was 76% (n = 83) at a mean of 37 years after the initial surgery. All participants completed the same study protocol including acoustic rhinometry (AR), rhinomanometry (RM), anterior rhinoscopy, and questionnaires regarding self-experienced nasal symptoms. Results: A reduced volume of the anterior nasal cavity on the operated side (measured by AR) correlated to an expressed wish by the patient to change the function of the nose. A similar correlation was seen for the minimal cross-sectional area of anterior nasal cavity on the operated side. Furthermore, correlations were found between smaller volume and area of nasal cavity and a greater frequency of nasal obstruction. No further correlations were found. Conclusion: Objective measurements partly correlate to the clinical picture among adults treated for UCLP. However, these need to be combined with findings at clinical examination and patient self-assessment to represent the complete clinical picture. (C) 2017 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.
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29. |
- Ramstad, Robin, 1986-, et al.
(author)
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Effects of the crustal magnetic fields on the Martian atmospheric ion escape rate
- 2016
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In: Journal of Geophysical Research - Space Physics. - 2169-9380 .- 2169-9402. ; 43:20, s. 10574-10579
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Journal article (peer-reviewed)abstract
- Eight years (2007–2015) of ion flux measurements from Mars Express are used to statisticallyinvestigate the influence of the Martian magnetic crustal fields on the atmospheric ion escape rate.We combine all Analyzer of Space Plasmas and Energetic Atoms/Ion Mass Analyzer (ASPERA-3/IMA)measurements taken during nominal upstream solar wind and solar extreme ultraviolet conditions tocompute global average ion distribution functions, individually for the north/south hemispheres and forvarying solar zenith angles (SZAs) of the strongest crustal magnetic field. Escape rates are subsequentlycalculated from each of the average distribution functions. The maximum escape rate (4.2 ± 1.2) × 1024 s−1 is found for SZA = 60∘–80∘, while the minimum escape rate (1.7±0.6)×1024 s−1 is found for SZA = 28∘–60∘,showing that the dayside orientation of the crustal fields significantly affects the global escape rate (p=97%). However, averaged over time, independent of SZA, we find no statistically significant difference inthe escape rates from the two hemispheres (escape from southern hemisphere 46% ± 18% of global rate).
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30. |
- Ramstad, Robin, 1986-, et al.
(author)
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Global Mars-solar wind coupling and ion escape
- 2017
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In: Journal of Geophysical Research - Space Physics. - Washington : American Geophysical Union (AGU). - 2169-9380 .- 2169-9402. ; 122:8, s. 8051-8062
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Journal article (peer-reviewed)abstract
- Loss of the early Martian atmosphere is often thought to have occurred due to an effective transfer of the solar wind energy through the Martian induced magnetic barrier to the ionosphere. We have quantified the coupling efficiency by comparing the power of the heavy ion outflow with the available power supplied by the upstream solar wind. Constraining upstream solar wind density nsw, velocity vsw, and EUV intensity IEUV/photoionizing flux FXUV in varying intervals reveals a decrease in coupling efficiency, k,with solar wind dynamic pressure as k ∝ pdyn−0.74±0.13 and with FXUV as k ∝ FXUV−2.28±0.30. Despite the decreasein coupling efficiency, higher FXUV enhances the cold ion outflow, increasing the total ion escape rate as Q(FXUV) = 1010(0.82 ± 0.05)FXUV. The discrepancy between coupling and escape suggests that ion escapefrom Mars is primarily production limited in the modern era, though decreased coupling may lead to an energy-limited solar wind interaction under early Sun conditions.
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31. |
- Ramstad, Robin, 1986-, et al.
(author)
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Mars Under Primordial Solar Wind Conditions: Mars Express Observations of the Strongest CME Detected at Mars Under Solar Cycle #24 and its Impact on Atmospheric Ion Escape
- 2017
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In: Geophysical Research Letters. - 0094-8276 .- 1944-8007.
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Journal article (peer-reviewed)abstract
- An extremely strong Coronal Mass Ejection (CME) impacted Mars on 12 July 2011, while theMars Express spacecraft was present inside the nightside ionosphere. Estimated solar wind density andspeed during the event are 39 particles cm−3 and 730 km/s, corresponding to nominal solar wind fluxat Mars when the solar system was ∼1.1 Ga old. Comparing with expected average atmospheric heavy ionfluxes under similar XUV conditions, the CME impact is found to have no significant effect on the escaperate 3.3 × 1024 s−1, with an upper limit at 1025 s−1 if the observed tail contraction is not taken into account.On the subsequent orbit, 7 h later after magnetosphere response, fluxes were only 2.4% of average. As such,even under primordial solar wind conditions we are unable to find support for a strong solar wind-driven ion escape, rather the main effect appears to be acceleration of the escaping ions by ×10–×20 typicalcharacteristic energy.
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32. |
- Ramstad, Robin, 1986-, et al.
(author)
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Solar wind- and EUV-dependent models for the shapes of the Martian plasma boundaries based on Mars Express measurements
- 2017
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In: Journal of Geophysical Research - Space Physics. - 2169-9380 .- 2169-9402. ; 122:7, s. 7279-7290
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Journal article (peer-reviewed)abstract
- The long operational life (2003-present) of Mars Express (MEX) has allowed the spacecraft tomake plasma measurements in the Martian environment over a wide range of upstream conditions. Wehave analyzed ∼7000 MEX orbits, covering three orders of magnitude in solar wind dynamic pressure, withdata from the on board Analyzer of Space Plasmas and Energetic Particles (ASPERA-3) package, mappingthe locations where MEX crosses the main plasma boundaries, induced magnetosphere boundary (IMB), ionosphere boundary (IB), and bow shock (BS). A coincidence scheme was employed, where data fromthe Ion Mass Analyzer (IMA) and the Electron Spectrometer (ELS) had to agree for a positive boundaryidentification, which resulted in crossings from 1083 orbit segments that were used to create dynamictwo-parameter (solar wind density, nsw, and velocity vsw) dependent global dynamic models for the IMB, IB,and BS. The modeled response is found to be individual to each boundary. The IMB scales mainly dependenton solar wind dynamic pressure and EUV intensity. The BS location closely follows the location of the IMB atthe subsolar point, though under extremely low nsw and vsw the BS assumes a more oblique shape. The IBclosely follows the IMB on the dayside and changes its nightside morphology with different trends for nswand vsw. We also investigate the influence of extreme ultraviolet (EUV) radiation on the IMB and BS, findingthat increased EUV intensity expands both boundaries.
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33. |
- Ramstad, Robin, 1986-, et al.
(author)
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The Martian atmospheric ion escape rate dependence on solar wind and solar EUV conditions : 1. Seven years of Mars Express observations
- 2015
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In: Journal of Geophysical Research - Planets. - 2169-9097 .- 2169-9100. ; 120:7, s. 1298-1309
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Journal article (peer-reviewed)abstract
- More than 7 years of ion flux measurements in the energy range 10 eV–15 keV have allowed the ASPERA-3/IMA (Analyzer of Space Plasmas and Energetic Ions/Ion Mass Analyzer) instrument on Mars Express to collect a large database of ion measurements in the Mars environment, over a wide range of upstream solar wind (density and velocity) and radiation (solar EUV intensity) conditions. We investigate the influence of these parameters on the Martian atmospheric ion escape rate by integrating IMA heavy ionflux measurements taken in the Martian tail at similar (binned) solar wind density (nsw), velocity (vsw), and solar EUV intensity (IEUV) conditions. For the same solar wind velocity and EUV intensity ranges (vsw and IEUV constrained), we find a statistically significant decrease of up to a factor of 3 in the atmospheric ion escape rate with increased average solar wind density (5.6 × 1024 s−1 to 1.9 × 1024 s−1 for 0.4 cm−3 and 1.4 cm−3, respectively). For low solar wind density (0.1–0.5 cm−3) and low EUV intensity, the escape rate increaseswith increasing solar wind velocity from 2.4 × 1024 s−1 to 5.6 × 1024 s−1. During high solar EUV intensities the escape fluxes are highly variable, leading to large uncertainties in the estimated escape rates; however, a statistically significant increase in the escape rate is found between low/high EUV for similar solar wind conditions. Empirical-analytical models for atmospheric escape are developed by fitting calculated escape rates to all sufficiently sampled upstream conditions.
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34. |
- Vorburger, Audrey, et al.
(author)
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Three‐Dimensional Modeling of Callisto's Surface Sputtered Exosphere Environment
- 2019
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In: Journal of Geophysical Research - Space Physics. - 2169-9380 .- 2169-9402. ; 124:8, s. 7157-7169
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Journal article (peer-reviewed)abstract
- We study the release of various elements from Callisto's surface into its exosphere by plasma sputtering. The cold Jovian plasma is simulated with a 3‐D plasma‐planetary interaction hybrid model, which produces 2‐D surface precipitation maps for magnetospheric H+, O+, O++, and S++. For the hot Jovian plasma, we assume isotropic precipitation onto the complete spherical surface. Two scenarios are investigated: one where no ionospheric shielding takes place and accordingly full plasma penetration is implemented (no‐ionosphere scenario) and one where an ionosphere lets virtually none of the cold plasma but all of the hot plasma reach Callisto's surface (ionosphere scenario). In the 3‐D exosphere model, neutral particles are sputtered from the surface and followed on their individual trajectories. The 3‐D density profiles show that whereas in the no‐ionosphere scenario the ram direction is favored, the ionosphere scenario produces almost uniform density profiles. In addition, the density profiles in the ionosphere scenario are reduced by a factor of ∼2.5 with respect to the no‐ionosphere scenario. We find that the Neutral Gas and Ion Mass Spectrometer, which is part of the Particle Environment Package on board the JUpiter ICy moons Explorer mission, will be able to detect the different sputter populations from Callisto's icy surface and the major sputter populations from Callisto's nonicy surface. The chemical composition of Callisto's exosphere can be directly linked to the chemical composition of its surface and will offer us information not only on Callisto's formation scenario but also on the building blocks of the Jupiter system.
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35. |
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