| 1. |
- Hilbert, Kevin, et al.
(författare)
-
Cortical and Subcortical Brain Alterations in Specific Phobia and Its Animal and Blood-Injection-Injury Subtypes: A Mega-Analysis From the ENIGMA Anxiety Working Group.
- 2024
-
Ingår i: The American Journal of Psychiatry. - 1535-7228.
-
Tidskriftsartikel (refereegranskat)abstract
- Specific phobia is a common anxiety disorder, but the literature on associated brain structure alterations exhibits substantial gaps. The ENIGMA Anxiety Working Group examined brain structure differences between individuals with specific phobias and healthy control subjects as well as between the animal and blood-injection-injury (BII) subtypes of specific phobia. Additionally, the authors investigated associations of brain structure with symptom severity and age (youths vs. adults).Data sets from 31 original studies were combined to create a final sample with 1,452 participants with phobia and 2,991 healthy participants (62.7% female; ages 5-90). Imaging processing and quality control were performed using established ENIGMA protocols. Subcortical volumes as well as cortical surface area and thickness were examined in a preregistered analysis.Compared with the healthy control group, the phobia group showed mostly smaller subcortical volumes, mixed surface differences, and larger cortical thickness across a substantial number of regions. The phobia subgroups also showed differences, including, as hypothesized, larger medial orbitofrontal cortex thickness in BII phobia (N=182) compared with animal phobia (N=739). All findings were driven by adult participants; no significant results were observed in children and adolescents.Brain alterations associated with specific phobia exceeded those of other anxiety disorders in comparable analyses in extent and effect size and were not limited to reductions in brain structure. Moreover, phenomenological differences between phobia subgroups were reflected in diverging neural underpinnings, including brain areas related to fear processing and higher cognitive processes. The findings implicate brain structure alterations in specific phobia, although subcortical alterations in particular may also relate to broader internalizing psychopathology.
|
|
| 2. |
- Hudson, Lawrence N, et al.
(författare)
-
The database of the PREDICTS (Projecting Responses of Ecological Diversity In Changing Terrestrial Systems) project
- 2017
-
Ingår i: Ecology and Evolution. - : John Wiley & Sons. - 2045-7758. ; 7:1, s. 145-188
-
Tidskriftsartikel (refereegranskat)abstract
- The PREDICTS project-Projecting Responses of Ecological Diversity In Changing Terrestrial Systems (www.predicts.org.uk)-has collated from published studies a large, reasonably representative database of comparable samples of biodiversity from multiple sites that differ in the nature or intensity of human impacts relating to land use. We have used this evidence base to develop global and regional statistical models of how local biodiversity responds to these measures. We describe and make freely available this 2016 release of the database, containing more than 3.2 million records sampled at over 26,000 locations and representing over 47,000 species. We outline how the database can help in answering a range of questions in ecology and conservation biology. To our knowledge, this is the largest and most geographically and taxonomically representative database of spatial comparisons of biodiversity that has been collated to date; it will be useful to researchers and international efforts wishing to model and understand the global status of biodiversity.
|
|
| 3. |
- Zamora, Juan Carlos, et al.
(författare)
-
Considerations and consequences of allowing DNA sequence data as types of fungal taxa
- 2018
-
Ingår i: IMA Fungus. - : INT MYCOLOGICAL ASSOC. - 2210-6340 .- 2210-6359. ; 9:1, s. 167-185
-
Tidskriftsartikel (refereegranskat)abstract
- Nomenclatural type definitions are one of the most important concepts in biological nomenclature. Being physical objects that can be re-studied by other researchers, types permanently link taxonomy (an artificial agreement to classify biological diversity) with nomenclature (an artificial agreement to name biological diversity). Two proposals to amend the International Code of Nomenclature for algae, fungi, and plants (ICN), allowing DNA sequences alone (of any region and extent) to serve as types of taxon names for voucherless fungi (mainly putative taxa from environmental DNA sequences), have been submitted to be voted on at the 11th International Mycological Congress (Puerto Rico, July 2018). We consider various genetic processes affecting the distribution of alleles among taxa and find that alleles may not consistently and uniquely represent the species within which they are contained. Should the proposals be accepted, the meaning of nomenclatural types would change in a fundamental way from physical objects as sources of data to the data themselves. Such changes are conducive to irreproducible science, the potential typification on artefactual data, and massive creation of names with low information content, ultimately causing nomenclatural instability and unnecessary work for future researchers that would stall future explorations of fungal diversity. We conclude that the acceptance of DNA sequences alone as types of names of taxa, under the terms used in the current proposals, is unnecessary and would not solve the problem of naming putative taxa known only from DNA sequences in a scientifically defensible way. As an alternative, we highlight the use of formulas for naming putative taxa (candidate taxa) that do not require any modification of the ICN.
|
|
| 4. |
|
|
| 5. |
|
|
| 6. |
|
|
| 7. |
- Behlke, Rico, et al.
(författare)
-
Solitary structures associated with short large-amplitude magnetic structures (SLAMS) upstream of the Earth's quasi-parallel bow shock
- 2004
-
Ingår i: Geophysical Research Letters. - 0094-8276 .- 1944-8007. ; 31:16
-
Tidskriftsartikel (refereegranskat)abstract
- [1] For the first time, solitary waves (SWs) have been observed within short large-amplitude magnetic structures (SLAMS) upstream of the Earth's quasi-parallel bow shock. The SWs often occur as bipolar pulses in the electric field data and move parallel to the background magnetic field at velocities of v = 400–1200 km/s. They have peak-to-peak amplitudes in the parallel electric field of up to E′∥ = 65 mV/m and parallel scale sizes of L∥ ∼ 10 λD. The bipolar solitary waves exhibit negative potential structures of ∣Φ∥∣ = 0.4–2.2 V, i.e., eΦ∥/kTe ∼ 0.1. None of the theories commonly used to describe SWs adequately address these negative potential structures moving at velocities above the ion thermal speed in a weakly magnetized plasma.
|
|
| 8. |
- Botling, Johan, et al.
(författare)
-
Biomarker Discovery in Non-Small Cell Lung Cancer : Integrating Gene Expression Profiling, Meta-analysis, and Tissue Microarray Validation
- 2013
-
Ingår i: Clinical Cancer Research. - 1078-0432 .- 1557-3265. ; 19:1, s. 194-204
-
Tidskriftsartikel (refereegranskat)abstract
- Purpose: Global gene expression profiling has been widely used in lung cancer research to identify clinically relevant molecular subtypes as well as to predict prognosis and therapy response. So far, the value of these multigene signatures in clinical practice is unclear, and the biologic importance of individual genes is difficult to assess, as the published signatures virtually do not overlap.Experimental Design: Here, we describe a novel single institute cohort, including 196 non-small lung cancers (NSCLC) with clinical information and long-term follow-up. Gene expression array data were used as a training set to screen for single genes with prognostic impact. The top 450 probe sets identified using a univariate Cox regression model (significance level P < 0.01) were tested in a meta-analysis including five publicly available independent lung cancer cohorts (n = 860).Results: The meta-analysis revealed 14 genes that were significantly associated with survival (P < 0.001) with a false discovery rate < 1%. The prognostic impact of one of these genes, the cell adhesion molecule 1 (CADM1), was confirmed by use of immunohistochemistry on tissue microarrays from 2 independent NSCLC cohorts, altogether including 617 NSCLC samples. Low CADM1 protein expression was significantly associated with shorter survival, with particular influence in the adenocarcinoma patient subgroup.Conclusions: Using a novel NSCLC cohort together with a meta-analysis validation approach, we have identified a set of single genes with independent prognostic impact. One of these genes, CADM1, was further established as an immunohistochemical marker with a potential application in clinical diagnostics. Clin Cancer Res; 19(1); 194-204. (c) 2012 AACR.
|
|
| 9. |
|
|
| 10. |
- Hudson, Lawrence N., et al.
(författare)
-
The PREDICTS database : a global database of how local terrestrial biodiversity responds to human impacts
- 2014
-
Ingår i: Ecology and Evolution. - : Wiley. - 2045-7758. ; 4:24, s. 4701-4735
-
Tidskriftsartikel (refereegranskat)abstract
- Biodiversity continues to decline in the face of increasing anthropogenic pressures such as habitat destruction, exploitation, pollution and introduction of alien species. Existing global databases of species' threat status or population time series are dominated by charismatic species. The collation of datasets with broad taxonomic and biogeographic extents, and that support computation of a range of biodiversity indicators, is necessary to enable better understanding of historical declines and to project - and avert - future declines. We describe and assess a new database of more than 1.6 million samples from 78 countries representing over 28,000 species, collated from existing spatial comparisons of local-scale biodiversity exposed to different intensities and types of anthropogenic pressures, from terrestrial sites around the world. The database contains measurements taken in 208 (of 814) ecoregions, 13 (of 14) biomes, 25 (of 35) biodiversity hotspots and 16 (of 17) megadiverse countries. The database contains more than 1% of the total number of all species described, and more than 1% of the described species within many taxonomic groups - including flowering plants, gymnosperms, birds, mammals, reptiles, amphibians, beetles, lepidopterans and hymenopterans. The dataset, which is still being added to, is therefore already considerably larger and more representative than those used by previous quantitative models of biodiversity trends and responses. The database is being assembled as part of the PREDICTS project (Projecting Responses of Ecological Diversity In Changing Terrestrial Systems - ). We make site-level summary data available alongside this article. The full database will be publicly available in 2015.
|
|
| 11. |
- McGinn, Steven, et al.
(författare)
-
New Technologies for DNA analysis-A review of the READNA Project.
- 2016
-
Ingår i: New Biotechnology. - : Elsevier BV. - 1876-4347 .- 1871-6784.
-
Forskningsöversikt (refereegranskat)abstract
- The REvolutionary Approaches and Devices for Nucleic Acid analysis (READNA) project received funding from the European Commission for 4 1/2 years. The objectives of the project revolved around technological developments in nucleic acid analysis. The project partners have discovered, created and developed a huge body of insights into nucleic acid analysis, ranging from improvements and implementation of current technologies to the most promising sequencing technologies that constitute a 3(rd) and 4(th) generation of sequencing methods with nanopores and in situ sequencing, respectively.
|
|
| 12. |
|
|
| 13. |
- Allen, R. C., et al.
(författare)
-
A statistical study of EMIC waves observed by Cluster : 1. Wave properties
- 2014
-
Ingår i: 2014 XXXITH URSI General Assembly And Scientific Symposium (URSI GRASS). - 9781467352253
-
Konferensbidrag (refereegranskat)abstract
- Electromagnetic ion cyclotron (EMIC) waves are an important mechanism for particle energization and losses inside the magnetosphere. In order to better understand the effects of these waves on particle dynamics, detailed information about the ellipticity, normal angle, energy propagation angle distributions, and local plasma parameters are required. Previous statistical studies have used in situ observations to investigate the distribution of these parameters in the L-MLT frame within a limited MLAT range. In this study, we present a statistical analysis of EMIC wave properties using ten years (2001-2010) of data from Cluster, totaling 17,987 minutes of wave activity. Due to the polar orbit of Cluster, we are able to investigate EMIC waves at all MLATs and MLTs. This allows us to further investigate the MLAT dependence of various wave properties inside different MLT sectors and further explore the effects of Shabansky orbits on EMIC wave generation and propagation. The current paper focuses on the wave occurrence distribution as well as the distribution of wave properties.
|
|
| 14. |
- Allen, R. C., et al.
(författare)
-
A statistical study of EMIC waves observed by Cluster : 2. Associated plasma conditions
- 2016
-
Ingår i: Journal of Geophysical Research - Space Physics. - 2169-9380 .- 2169-9402. ; 121:7, s. 6458-6479
-
Tidskriftsartikel (refereegranskat)abstract
- This is the second in a pair of papers discussing a statistical study of electromagnetic ion cyclotron (EMIC) waves detected during 10years (2001-2010) of Cluster observations. In the first paper, an analysis of EMIC wave properties (i.e., wave power, polarization, normal angle, and wave propagation angle) is presented in both the magnetic latitude (MLAT)-distance as well as magnetic local time (MLT)-L frames. This paper focuses on the distribution of EMIC wave-associated plasma conditions as well as two EMIC wave generation proxies (the electron plasma frequency to gyrofrequency ratio proxy and the linear theory proxy) in these same frames. Based on the distributions of hot H+ anisotropy, electron and hot H+ density measurements, hot H+ parallel plasma beta, and the calculated wave generation proxies, three source regions of EMIC waves appear to exist: (1) the well-known overlap between cold plasmaspheric or plume populations with hot anisotropic ring current populations in the postnoon to dusk MLT region; (2) regions all along the dayside magnetosphere at high L shells related to dayside magnetospheric compression and drift shell splitting; and (3) off-equator regions possibly associated with the Shabansky orbits in the dayside magnetosphere.
|
|
| 15. |
- Allen, R. C., et al.
(författare)
-
A statistical study of EMIC waves observed by Cluster : 1. Wave properties
- 2015
-
Ingår i: Journal of Geophysical Research - Space Physics. - 2169-9380 .- 2169-9402. ; 120:7, s. 5574-5592
-
Tidskriftsartikel (refereegranskat)abstract
- Electromagnetic ion cyclotron (EMIC) waves are an important mechanism for particle energization and losses inside the magnetosphere. In order to better understand the effects of these waves on particle dynamics, detailed information about the occurrence rate, wave power, ellipticity, normal angle, energy propagation angle distributions, and local plasma parameters are required. Previous statistical studies have used in situ observations to investigate the distribution of these parameters in the magnetic local time versus L-shell (MLT-L) frame within a limited magnetic latitude (MLAT) range. In this study, we present a statistical analysis of EMIC wave properties using 10years (2001-2010) of data from Cluster, totaling 25,431min of wave activity. Due to the polar orbit of Cluster, we are able to investigate EMIC waves at all MLATs and MLTs. This allows us to further investigate the MLAT dependence of various wave properties inside different MLT sectors and further explore the effects of Shabansky orbits on EMIC wave generation and propagation. The statistical analysis is presented in two papers. This paper focuses on the wave occurrence distribution as well as the distribution of wave properties. The companion paper focuses on local plasma parameters during wave observations as well as wave generation proxies.
|
|
| 16. |
- Allen, R. C., et al.
(författare)
-
Multiple bidirectional EMIC waves observed by Cluster at middle magnetic latitudes in the dayside magnetosphere
- 2013
-
Ingår i: Journal of Geophysical Research: Space Physics. - : American Geophysical Union (AGU). - 2169-9380 .- 2169-9402. ; 118:10, s. 6266-6278
-
Tidskriftsartikel (refereegranskat)abstract
- It is well accepted that the propagation of electromagnetic ion cyclotron (EMIC) waves are bidirectional near their source regions and unidirectional when away from these regions. The generally believed source region for EMIC waves is around the magnetic equatorial plane. Here we describe a series of EMIC waves in the Pc1 (0.2-5 Hz) frequency band above the local He+ cyclotron frequency observed in situ by all four Cluster spacecraft on 9 April 2005 at midmagnetic latitudes (MLAT = similar to 33 degrees-49 degrees) with L = 10.7-11.5 on the dayside (MLT = 10.3-10.4). A Poynting vector spectrum shows that the wave packets consist of multiple groups of packets propagating bidirectionally, rather than unidirectionally, away from the equator, while the local plasma conditions indicate that the spacecraft are entering into a region sufficient for local wave excitation. One possible interpretation is that, while part of the observed waves are inside their source region, the others are either close enough to the source region, or mixed with the wave packets from multiple source regions at different latitudes.
|
|
| 17. |
- Alm, Love, et al.
(författare)
-
Magnetotail Hall Physics in the Presence of Cold Ions
- 2018
-
Ingår i: Geophysical Research Letters. - : Blackwell Publishing Ltd. - 0094-8276 .- 1944-8007. ; 45:20, s. 10,941-10,950
-
Tidskriftsartikel (refereegranskat)abstract
- We present the first in situ observation of cold ionospheric ions modifying the Hall physics of magnetotail reconnection. While in the tail lobe, Magnetospheric Multiscale mission observed cold (tens of eV) E × B drifting ions. As Magnetospheric Multiscale mission crossed the separatrix of a reconnection exhaust, both cold lobe ions and hot (keV) ions were observed. During the closest approach of the neutral sheet, the cold ions accounted for ∼30% of the total ion density. Approximately 65% of the initial cold ions remained cold enough to stay magnetized. The Hall electric field was mainly supported by the j × B term of the generalized Ohm's law, with significant contributions from the ∇·P e and v c ×B terms. The results show that cold ions can play an important role in modifying the Hall physics of magnetic reconnection even well inside the plasma sheet. This indicates that modeling magnetic reconnection may benefit from including multiscale Hall physics.
|
|
| 18. |
- Alm, Love, et al.
(författare)
-
MMS Observations of Multiscale Hall Physics in the Magnetotail
- 2019
-
Ingår i: Geophysical Research Letters. - : AMER GEOPHYSICAL UNION. - 0094-8276 .- 1944-8007.
-
Tidskriftsartikel (refereegranskat)abstract
- We present Magnetospheric Multiscale mission (MMS) observations of Hall physics in the magnetotail, which compared to dayside Hall physics is a relatively unexplored topic. The plasma consists of electrons, moderately cold ions (T similar to 1.5 keV) and hot ions (T similar to 20 keV). MMS can differentiate between the cold ion demagnetization region and hot ion demagnetization regions, which suggests that MMS was observing multiscale Hall physics. The observed Hall electric field is compared with a generalized Ohm's law, accounting for multiple ion populations. The cold ion population, despite its relatively high initial temperature, has a significant impact on the Hall electric field. These results show that multiscale Hall physics is relevant over a much larger temperature range than previously observed and is relevant for the whole magnetosphere as well as for other astrophysical plasma.
|
|
| 19. |
- Alvesson, Mats, et al.
(författare)
-
A Stupidity-Based Theory of Organizations
- 2012
-
Ingår i: Journal of Management Studies. - : Wiley. - 1467-6486 .- 0022-2380. ; 49:7, s. 1194-1220
-
Tidskriftsartikel (refereegranskat)abstract
- In this paper we question the one-sided thesis that contemporary organizations rely on the mobilization of cognitive capacities. We suggest that severe restrictions on these capacities in the form of what we call functional stupidity are an equally important if under-recognized part of organizational life. Functional stupidity refers to an absence of reflexivity, a refusal to use intellectual capacities in other than myopic ways, and avoidance of justifications. We argue that functional stupidity is prevalent in contexts dominated by economy in persuasion which emphasizes image and symbolic manipulation. This gives rise to forms of stupidity management that repress or marginalize doubt and block communicative action. In turn, this structures individuals' internal conversations in ways that emphasize positive and coherent narratives and marginalize more negative or ambiguous ones. This can have productive outcomes such as providing a degree of certainty for individuals and organizations. But it can have corrosive consequences such as creating a sense of dissonance among individuals and the organization as a whole. The positive consequences can give rise to self-reinforcing stupidity. The negative consequences can spark dialogue, which may undermine functional stupidity.
|
|
| 20. |
- Alvesson, Mats, et al.
(författare)
-
Critical leadership studies: The case for critical performativity
- 2012
-
Ingår i: Human Relations. - : SAGE Publications. - 0018-7267 .- 1741-282X. ; 65:3, s. 367-390
-
Tidskriftsartikel (refereegranskat)abstract
- Existing accounts of leadership are underpinned by two dominant approaches: functionalist studies, which have tried to identify correlations between variables associated with leadership; and interpretive studies, which have tried to trace out the meaning-making process associated with leadership. Eschewing these approaches, we turn to an emerging strand of literature that develops a critical approach to leadership. This literature draws our attention to the dialectics of control and resistance and the ideological aspect of leadership. However, it largely posits a negative critique of leadership. We think this is legitimate and important, but extend this agenda. We posit a performative critique of leadership that emphasizes tactics of circumspect care, progressive pragmatism and searching for present potentialities. We use these tactics to sketch out a practice of deliberated leadership that involves collective reflection on when, what kind and if leadership is appropriate.
|
|
| 21. |
- Alvesson, Mats, et al.
(författare)
-
Critical perspectives on leadership
- 2014
-
Ingår i: The Oxford Handbook of Leadership and Organizations. - : Oxford University Press. - 9780199755615
-
Bokkapitel (refereegranskat)abstract
- This chapter reviews the emerging body of literature on critical theories of leadership. It begins by putting critical approaches to leadership in the context of broader debates about leadership. It notes that most existing work builds on either functional or interpretive assumptions. After noting some of the shortcomings with these directions, this chapter offers an alternative set of ideas based on critical theory. These suggest that leadership should be denaturalized and studied reflexively, and that this research should be done with a noninstrumental intent. The chapter then reviews the growing body of work that has built on these ideas. This work addresses issues including ideology, identity, exclusions and inclusions, and interventions. The chapter concludes by outlining a range of areas for future research.
|
|
| 22. |
- Alvesson, Mats, et al.
(författare)
-
Does leadership create stupidity?
- 2013
-
Ingår i: Critical Perspectives on Leadership – Emotion, Toxicity and Dysfunction. - 978 0 85793 112 2
-
Bokkapitel (refereegranskat)
|
|
| 23. |
|
|
| 24. |
- Alvesson, Mats, et al.
(författare)
-
Neo-Institutional Theory and Organization Studies : A Mid-Life Crisis?
- 2019
-
Ingår i: Organization Studies. - : SAGE Publications. - 0170-8406 .- 1741-3044. ; 40:2, s. 199-218
-
Tidskriftsartikel (refereegranskat)abstract
- We trace the development of neo-institutional theory in Organization Studies from a marginal topic to the dominant theory. We show how it has evolved from infancy, through adolescence and early adulthood to being a fully mature theory, which we think is now facing a mid-life crisis. Some of the features of this mid-life crisis include over-reach, myopia, tautology, pseudo-progress and re-inventing the wheel. To address these problems, we argue that institutional theorists should limit the range of the concept, sharpen their lens, avoid tautologies and problematize the concept. By doing this, we think institutional theorists could develop a narrower and more focused conception of institutions.
|
|
| 25. |
|
|
| 26. |
- Alvesson, Mats, et al.
(författare)
-
(Un)Conditional surrender? Why do professionals willingly comply with managerialism
- 2016
-
Ingår i: Journal of Organizational Change Management. - 0953-4814. ; 29:1, s. 1-19
-
Tidskriftsartikel (refereegranskat)abstract
- Purpose– The purpose of this paper is to explore the question – why do professionals surrender their autonomy? This paper looks at the case of academics, in particular business school academics. It traces how this group of professionals have progressively surrendered their autonomy and complied with the demands of managerialism. Design/methodology/approach – This largely theoretical paper looks to develop an understanding of (over)compliance with the bureaucratization of research using the four faces of power – coercive, agenda setting, ideological and discursive.Findings– The discussion of this paper argues that the surrendering of autonomy has been reinforced through coercive forms of power like rewards and punishment and bureaucratization; manipulation and mainstreaming through pushing a particular version of research to the top of the agenda; domination through shaping norms and values; and subjectification through creating new identities.Originality/value– The paper explores how academics deal with tensions and paradoxes such as compliance and resistance, as well as love of work and loathing of it. To deal with these paradoxes, academics often treat their work as a game and see themselves as players. While this process enables academics to reconcile themselves with their loss of autonomy, it has troubling collective outcomes: the production of increasing uninteresting and irrelevant research.
|
|
| 27. |
|
|
| 28. |
- Alvesson, Mats, et al.
(författare)
-
Uninhibited Institutionalisms
- 2019
-
Ingår i: Journal of Management Inquiry. - : SAGE Publications. - 1056-4926 .- 1552-6542. ; 28:2, s. 119-127
-
Tidskriftsartikel (refereegranskat)abstract
- Institutional theory (IT) is a very influential set of approaches in organization studies. There is increasing critique that the set is becoming uninhibited: too broad, dispersed, and confusing. Efforts to rejuvinate the field(s) have led to all-embracing definitions and efforts to account for too much, which makes it difficult to identify what is distinct about the assembly of research. This article discusses critically the state of IT and suggests some reconceptualizations of institution and institutional theory and points at some alternative lines of development.
|
|
| 29. |
- Amata, E., et al.
(författare)
-
Experimental study of nonlinear interaction of plasma flow with charged thin current sheets : 1. Boundary structure and motion
- 2006
-
Ingår i: Nonlinear processes in geophysics. - 1023-5809 .- 1607-7946. ; 13:4, s. 365-376
-
Tidskriftsartikel (refereegranskat)abstract
- We study plasma transport at a thin magnetopause (MP), described hereafter as a thin current sheet (TCS), observed by Cluster at the southern cusp on 13 February 2001 around 20:01 UT. The Cluster observations generally agree with the predictions of the Gas Dynamic Convection Field (GDCF) model in the magnetosheath (MSH) up to the MSH boundary layer, where significant differences are seen. We find for the MP a normal roughly along the GSE x-axis, which implies a clear departure from the local average MP normal, a similar to 90 km thickness and an outward speed of 35 km/s. Two populations are identified in the MSH boundary layer: the first one roughly perpendicular to the MSH magnetic field, which we interpret as the "incident" MSH plasma, the second one mostly parallel to B. Just after the MP crossing a velocity jet is observed with a peak speed of 240 km/s, perpendicular to B, with M-A=3 and beta> 10 (peak value 23). The magnetic field clock angle rotates by 70 degrees across the MP. E-x is the main electric field component on both sides of the MP, displaying a bipolar signature, positive on the MSH side and negative on the opposite side, corresponding to a similar to 300 V electric potential jump across the TCS. The E x B velocity generally coincides with the perpendicular velocity measured by CIS; however, in the speed jet a difference between the two is observed, which suggests the need for an extra flow source. We propose that the MP TCS can act locally as an obstacle for low-energy ions (<350 eV), being transparent for ions with larger gyroradius. As a result, the penetration of plasma by finite gyroradius is considered as a possible source for the jet. The role of reconnection is briefly discussed. The electrodynamics of the TCS along with mass and momentum transfer across it are further discussed in the companion paper by Savin et al. (2006).
|
|
| 30. |
- Amato, Fulvio, et al.
(författare)
-
Urban air quality : The challenge of traffic non-exhaust emissions
- 2014
-
Ingår i: Journal of Hazardous Materials. - : Elsevier BV. - 0304-3894 .- 1873-3336. ; 275, s. 31-36
-
Tidskriftsartikel (refereegranskat)abstract
- About 400,000 premature adult deaths attributable to air pollution occur each year in the European Region. Road transport emissions account for a significant share of this burden. While important technological improvements have been made for reducing particulate matter (PM) emissions from motor exhausts, no actions are currently in place to reduce the non-exhaust part of emissions such as those from brake wear, road wear, tyre wear and road dust resuspension. These "non-exhaust" sources contribute easily as much and often more than the tailpipe exhaust to the ambient air PM concentrations in cities, and their relative contribution to ambient PM is destined to increase in the future, posing obvious research and policy challenges.This review highlights the major and more recent research findings in four complementary fields of research and seeks to identify the current gaps in research and policy with regard to non-exhaust emissions. The objective of this article is to encourage and direct future research towards an improved understanding on the relationship between emissions, concentrations, exposure and health impact and on the effectiveness of potential remediation measures in the urban environment.
|
|
| 31. |
- Andersson, Leif, et al.
(författare)
-
Ecological adaptation in cod and herring and possible consequences of future climate change in the Baltic Sea
- 2023
-
Ingår i: Frontiers in Marine Science. - : Frontiers Media S.A.. - 2296-7745. ; 10
-
Forskningsöversikt (refereegranskat)abstract
- The Atlantic herring and Atlantic cod are two marine fish species that have successfully adapted to the brackish Baltic Sea, and the former is able to spawn in near-freshwater conditions in the inner Gulf of Bothnia. Here, we review the state of current knowledge concerning ecological adaptation in the two species and make an attempt to predict how they will be able to cope with future climate change. Previous whole genome sequencing studies in Atlantic herring have revealed hundreds of genetic loci underlying ecological adaptation, including several loci that show very strong associations to variation in salinity and temperature. These results suggest the existence of standing genetic variation available for adaptation to a changing environment. However, although Atlantic herring probably has the genetic potential to adapt, its future status also depends on how climate change will affect plankton production and competing species, such as sprat and three-spined stickleback. In cod, the situation is challenging, as there is only one true Baltic population, spawning east of Bornholm and then dispersing towards the east and north. This Baltic cod population is threatened by overfishing, low oxygen levels in benthic waters and generally bad physiological condition of individual fish, in addition to being completely isolated from gene flow from nearby cod populations at the entrance of the Baltic Sea.
|
|
| 32. |
- Andre, C., et al.
(författare)
-
Fertilization efficiency and gamete viability of a sessile, free-spawning bivalve, Cerastoderma edule
- 1995
-
Ingår i: Ophelia. - : Informa UK Limited. - 0078-5326. ; 43:3, s. 215-227
-
Tidskriftsartikel (refereegranskat)abstract
- The fertilization biology of the free-spawning bivalve Cerastoderma edule was studied in the laboratory. Fertilization success declined drastically with decreasing sperm concentration. Viability of both eggs and sperm decreased with age so that no fertilization took place after 4-8 hours. A dilution model suggests that in the field sperm is rapidly diluted to concentrations that would result in very low fertilization efficiencies. The dilution process thus operates on a much smaller time scale than gamete ageing, indicating that most eggs are fertilized close to spawning males. However, it is also shown that under certain circumstances high concentrations of sperm may accumulate over dense populations of bivalves.
|
|
| 33. |
- Andre, C., et al.
(författare)
-
Predation on Settling Bivalve Larvae by Benthic Suspension Feeders - the Role of Hydrodynamics and Larval Behavior
- 1993
-
Ingår i: Marine Ecology-Progress Series. - 0171-8630. ; 97:2, s. 183-192
-
Tidskriftsartikel (refereegranskat)abstract
- Predation by the suspension-feeding infaunal bivalve Cerastoderma edule on settling C. edule larvae was studied in a flume boundary-layer flow. The density of settled larvae was reduced by 33% in an area of 5 cm2 enclosing individual adults. Mean survival time for competent C. edule larvae drifting over sediment populated with feeding adults (380 ind. m-2) was 64 s, and 75% of the observed larvae were inhaled by adults. Observations of the siphonal currents produced by C. edule and the swimming behaviour of larvae were combined in a computer model to assess the importance of adult density and boundary-layer flow on the predation risk experienced by settling larvae. Survival of settling larvae decreased drastically with increasing adult density, whereas increased flow velocity caused only a slightly higher predation risk. Although reduction in larval settlement on the scale of individual adults may be small or moderate, inhalation of settling larvae by populations of resident suspension feeders may cause a significant decrease in settlement on a larger scale (10(1) to 10(3) m).
|
|
| 34. |
- Andre, C., et al.
(författare)
-
Species identification of bivalve larvae using random amplified polymorphic DNA (RAPD): differentiation between Cerastoderma edule and C-lamarcki
- 1999
-
Ingår i: Journal of the Marine Biological Association of the United Kingdom. - 0025-3154. ; 79:3, s. 563-565
-
Tidskriftsartikel (refereegranskat)abstract
- The polymerase chain reaction (PCR) was used to produce species-specific DNA markers (RAPDs) from two sibling cockle species and five other co-occurring intertidal bivalves. Amplification reactions with one single primer readily distinguished larvae and adults of Cerastoderma edule from larvae and adults of C. lamarcki, and from adults of Mya arenaria Macoma balthica, Scrobicularia plana, Venerupis pulastra and Mytilus edulis. Random amplified polymorphic DNA (RAPD) is suggested as a simple and quick method to determine species identity in taxa that are difficult to identify on the basis of morphological characters alone, such as marine bivalve larvae.
|
|
| 35. |
|
|
| 36. |
|
|
| 37. |
- André, Malin, et al.
(författare)
-
Asking for ’rules of thumb’ : a way to discover tacit knowledge in general practice
- 2002
-
Ingår i: Family Practice. - : Oxford University Press (OUP). - 0263-2136 .- 1460-2229. ; 19:6, s. 617-622
-
Tidskriftsartikel (refereegranskat)abstract
- Background. Research in decision-making has identified heuristics (rules of thumb) as shortcuts to simplify search and choice. Objective. To find out if GPs recognize the use of rules of thumb and if they could describe what they looked like. Methods. An explorative and descriptive study was set up using focus group interviews. The interview guide contained the questions: Do you recognize the use of rules of thumb? Are you able to give some examples? What are the benefits and dangers in using rules of thumb? Where do they come from? The interviews were transcribed and analysed using the templates in the interview guide, and the examples of rules were classified by editing analysis. Results. Four groups with 23 GPs were interviewed. GPs recognized using rules of thumb, producing examples covering different aspects of the consultation. The rules for somatic problems were formulated as axiomatic simplified medical knowledge and taken for granted, while rules for psychosocial problems were formulated as expressions of individual experience and were followed by an explanation. The rules seemed unaffected by the sparse objections given. A GP’s clinical experience was judged a prerequisite for applying the rules. The origin of many rules was via word-of-mouth from a colleague. The GPs acknowledged the benefits of using the rules, thereby simplifying work. Conclusion. GPs recognize the use of rules of thumb as an immediate and semiconscious kind of knowledge that could be called tacit knowledge. Using rules of thumb might explain why practice remains unchanged although educational activities result in more elaborate knowledge.
|
|
| 38. |
|
|
| 39. |
|
|
| 40. |
|
|
| 41. |
|
|
| 42. |
|
|
| 43. |
|
|
| 44. |
|
|
| 45. |
|
|
| 46. |
- André, Mats, et al.
(författare)
-
Low-energy ions : A previously hidden solar system particle population
- 2012
-
Ingår i: Geophysical Research Letters. - 0094-8276 .- 1944-8007. ; 39, s. L03101-
-
Tidskriftsartikel (refereegranskat)abstract
- Ions with energies less than tens of eV originate from the Terrestrial ionosphere and from several planets and moons in the solar system. The low energy indicates the origin of the plasma but also severely complicates detection of the positive ions onboard sunlit spacecraft at higher altitudes, which often become positively charged to several tens of Volts. We discuss some methods to observe low-energy ions, including a recently developed technique based on the detection of the wake behind a charged spacecraft in a supersonic flow. Recent results from this technique show that low-energy ions typically dominate the density in large regions of the Terrestrial magnetosphere on the nightside and in the polar regions. These ions also often dominate in the dayside magnetosphere, and can change the dynamics of processes like magnetic reconnection. The loss of this low-energy plasma to the solar wind is one of the primary pathways for atmospheric escape from planets in our solar system. We combine several observations to estimate how common low-energy ions are in the Terrestrial magnetosphere and briefly compare with Mars, Venus and Titan.
|
|
| 47. |
- André, Mats, et al.
(författare)
-
Lower hybrid waves at comet 67P/Churyumov-Gerasimenko
- 2017
-
Ingår i: Monthly notices of the Royal Astronomical Society. - : OXFORD UNIV PRESS. - 0035-8711 .- 1365-2966. ; 469, s. S29-S38
-
Tidskriftsartikel (refereegranskat)abstract
- We investigate the generation of waves in the lower hybrid frequency range by density gradients in the near plasma environment of comet 67P/Churyumov-Gerasimenko. When the plasma is dominated by water ions from the comet, a situation with magnetized electrons and unmagnetized ions is favourable for the generation of lower hybrid waves. These waves can transfer energy between ions and electrons and reshape the plasma environment of the comet. We consider cometocentric distances out to a few hundred km. We find that when the electron motion is not significantly interrupted by collisions with neutrals, large average gradients within tens of km of the comet, as well as often observed local large density gradients at larger distances, are often likely to be favourable for the generation of lower hybrid waves. Overall, we find that waves in the lower hybrid frequency range are likely to be common in the near plasma environment.
|
|
| 48. |
- André, Mats, et al.
(författare)
-
Magnetic reconnection and cold plasma at the magnetopause
- 2010
-
Ingår i: Geophysical Research Letters. - 0094-8276 .- 1944-8007. ; 37:22, s. L22108-
-
Tidskriftsartikel (refereegranskat)abstract
- We report on detailed observations by the four Cluster spacecraft of magnetic reconnection and a Flux Transfer Event (FTE) at the magnetopause. We detect cold (eV) plasma at the magnetopause with two independent methods. We show that the cold ions can be essential for the electric field normal to the current sheet in the separatrix region at the edge of the FTE and for the associated acceleration of ions from the magnetosphere into the reconnection jet. The cold ions have small enough gyroradii to drift inside the limited separatrix region and the normal electric field can be balanced by this drift, E approximate to -v x B. The separatrix region also includes cold accelerated electrons, as part of the reconnection current circuit.
|
|
| 49. |
- André, Mats, et al.
(författare)
-
Magnetic reconnection and modification of the Hall physics due to cold ions at the magnetopause
- 2016
-
Ingår i: Geophysical Research Letters. - : Blackwell Publishing. - 0094-8276 .- 1944-8007. ; 43:13, s. 6705-6712
-
Tidskriftsartikel (refereegranskat)abstract
- Observations by the four Magnetospheric Multiscale spacecraft are used to investigate the Hall physics of a magnetopause magnetic reconnection separatrix layer. Inside this layer of currents and strong normal electric fields, cold (eV) ions of ionospheric origin can remain frozen-in together with the electrons. The cold ions reduce the Hall current. Using a generalized Ohm's law, the electric field is balanced by the sum of the terms corresponding to the Hall current, the vxB drifting cold ions, and the divergence of the electron pressure tensor. A mixture of hot and cold ions is common at the subsolar magnetopause. A mixture of length scales caused by a mixture of ion temperatures has significant effects on the Hall physics of magnetic reconnection.
|
|
| 50. |
- André, Mats, et al.
(författare)
-
Outflow of low-energy ions and the solar cycle
- 2015
-
Ingår i: Journal of Geophysical Research - Space Physics. - 2169-9380 .- 2169-9402. ; 120:2, s. 1072-1085
-
Tidskriftsartikel (refereegranskat)abstract
- Magnetospheric ions with energies less than tens of eV originate from the ionosphere. Positive low-energy ions are complicated to detect onboard sunlit spacecraft at higher altitudes, which often become positively charged to several tens of volts. We use two Cluster spacecraft and study low-energy ions with a technique based on the detection of the wake behind a charged spacecraft in a supersonic ion flow. We find that low-energy ions usually dominate the density and the outward flux in the geomagnetic tail lobes during all parts of the solar cycle. The global outflow is of the order of 10(26) ions/s and often dominates over the outflow at higher energies. The outflow increases by a factor of 2 with increasing solar EUV flux during a solar cycle. This increase is mainly due to the increased density of the outflowing population, while the outflow velocity does not vary much. Thus, the outflow is limited by the available density in the ionospheric source rather than by the energy available in the magnetosphere to increase the velocity.
|
|
