Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99


Any time

2019 ( 128 )

2018 ( 823 )

2017 ( 831 )

2016 ( 1189 )

Custom range...

Search Results: 1 - 10 of 532093 matches for " Johanna M. P. Baas "
All listed articles are free for downloading (OA Articles)
Page 1 /532093
Display every page Item
Human Fear Acquisition Deficits in Relation to Genetic Variants of the Corticotropin Releasing Hormone Receptor 1 and the Serotonin Transporter
Ivo Heitland, Lucianne Groenink, Elisabeth Y. Bijlsma, Ronald S. Oosting, Johanna M. P. Baas
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0063772
Abstract: The ability to identify predictors of aversive events allows organisms to appropriately respond to these events, and failure to acquire these fear contingencies can lead to maladaptive contextual anxiety. Recently, preclinical studies demonstrated that the corticotropin-releasing factor and serotonin systems are interactively involved in adaptive fear acquisition. Here, 150 healthy medication-free human subjects completed a cue and context fear conditioning procedure in a virtual reality environment. Fear potentiation of the eyeblink startle reflex (FPS) was measured to assess both uninstructed fear acquisition and instructed fear expression. All participants were genotyped for polymorphisms located within regulatory regions of the corticotropin releasing hormone receptor 1 (CRHR1 - rs878886) and the serotonin transporter (5HTTLPR). These polymorphisms have previously been linked to panic disorder and anxious symptomology and personality, respectively. G-allele carriers of CRHR1 (rs878886) showed no acquisition of fear conditioned responses (FPS) to the threat cue in the uninstructed phase, whereas fear acquisition was present in C/C homozygotes. Moreover, carrying the risk alleles of both rs878886 (G-allele) and 5HTTLPR (short allele) was associated with increased FPS to the threat context during this phase. After explicit instructions regarding the threat contingency were given, the cue FPS and context FPS normalized in all genotype groups. The present results indicate that genetic variability in the corticotropin-releasing hormone receptor 1, especially in interaction with the 5HTTLPR, is involved in the acquisition of fear in humans. This translates prior animal findings to the human realm.
No Impact of Deep Brain Stimulation on Fear-Potentiated Startle in Obsessive–Compulsive Disorder
Johanna M. P. Baas,Floris Klumpers,Mariska H. Mantione,Martijn Figee,Nienke C. Vulink,Ali Mazaheri,Damiaan Denys
Frontiers in Behavioral Neuroscience , 2014, DOI: 10.3389/fnbeh.2014.00305
Abstract: Deep brain stimulation (DBS) of the ventral internal capsule is effective in treating therapy refractory obsessive–compulsive disorder (OCD). Given the close proximity of the stimulation site to the stria terminalis (BNST), we hypothesized that the striking decrease in anxiety symptoms following DBS could be the result of the modulation of contextual anxiety. However, the effect of DBS in this region on contextual anxiety is as of yet unknown. Thus, the current study investigated the effect of DBS on contextual anxiety in an experimental threat of shock paradigm. Eight patients with DBS treatment for severe OCD were tested in a double-blind crossover design with randomly assigned 2-week periods of active and sham stimulation. DBS resulted in significant decrease of obsessive–compulsive symptoms, anxiety, and depression. However, even though the threat manipulation resulted in a clear context-potentiated startle effect, none of the parameters derived from the startle recordings was modulated by the DBS. This suggests that DBS in the ventral internal capsule is effective in treating anxiety symptoms of OCD without modulating the startle circuitry. We hypothesize that the anxiety symptoms present in OCD are likely distinct from the pathological brain circuits in defensive states of other anxiety disorders.
How to kickstart a national biobanking infrastructure – experiences and prospects of BBMRI-NL
M. Brandsma,F. Baas,P.I.W. de Bakker,E.P. Beem
Norsk Epidemiologi , 2012,
Abstract: -
CI and CO in the nearby spiral galaxies IC 342 and Maffei 2
F. P. Israel,F. Baas
Physics , 2003, DOI: 10.1051/0004-6361:20030479
Abstract: We present J=2-1, J=3-2, J=4-3 12CO and 492 GHz [CI] maps as well as J=2-1 and J=3-2 13CO measurements of the central regions in the nearby Sc galaxies IC 342 and Maffei 2. In both galaxies, the distribution of CO and [CI] is strongly concentrated towards the modest starburst centers. Both galaxies have nearly identical 12CO transitional ratios but the relative intensities of their 13CO and [CI] emission lines differ significantly and require modelling with a multi-component molecular gas. Both have a dense component (n(H2) = 10**4 - 10**5 cm**-3) with kinetic temperatures T(kin) = 10 - 20 K (IC 342) or 20 - 60 K (Maffei 2), and a less dense (IC 342: a few hundred cm**-3 at most; Maffei 2: about 3 x 10**3 cm**-3 and hotter (T(kin) = 100 - 150 K) component. In both galaxies, neutral and ionized atomic carbon amounts are between 1.5 and 2.5 times those of CO, and in both about half to two thirds of the molecular gas mass is associated with a hot PDR phase. Within R = 0.25 kpc, the center of IC 342 contains an (atomic and molecular) gas mass of 1 x 10**7 M(sun) and a peak face-on gas mass density of about 70 M(sun) pc**-2. For Maffei 2 these numbers are less clearly defined, mainly because of its uncertain distance and carbon abundance. We find a gass mass M(gas) > 0.5 x 10**7 M(sun) and a peak face-on gas mass density of about 35 M(sun) pc**-2.
Molecular Gas in the Bulge and Ring of NGC 7331
F. P. Israel,F. Baas
Physics , 1999,
Abstract: Maps of the J=2-1 12CO emission from the SbII galaxy NGC 7331 show a low-contrast ring at a radius of about 3.5 kpc. There is no evidence for a pronounced central hole in the CO distribution as claimed by others. The molecular ring is just outside the radius of peak emission from warm dust, but coincides with the peak of colder dust emission. Various 12CO and 13CO transitions have been observed from three positions including the center, which was also observed in the 492 GHz transition. The line measurements have been modelled by emission from a clumpy mixture of low-density molecular gas at about T(kin) = 10 K and high-density molecular gas at temperatures of 10 K and 20 K. The CO to H2 conversion factor in NGC 7331 is lower than that in the Milky Way, and lowest in the center of NGC 7331. The total interstellar gas mass is dominated by molecular hydrogen in the bulge and in the ring, and by atomic hydrogen outside the ring. Total hydrogen mass densities in the ring are about twice those in the bulge. Total gas to dynamic mass ratios increase from 1% in the bulge to 3% outside the ring. The bulge molecular gas may have originated in mass loss from bulge stars, in which case the molecular ring is probably the consequence of evacuation efficiency decreases at the outer bulge edge.
Neutral Atomic Carbon in Centers of Galaxies
F. P. Israel,F. Baas
Physics , 2001, DOI: 10.1051/0004-6361:20011736
Abstract: We present measurements of the emission from the centers of fifteen spiral galaxies in the 3P1-3P0 [CI] fine-structure transition at 492 GHz. Observed galaxy centers range from quiescent to starburst to active. The intensities of neutral carbon, the J=2-1 transition of 13CO and the J=4-3 transition of 12CO are compared in matched beams. Most galaxy centers emit more strongly in [CI] than in 13CO, completely unlike the situation pertaining to Galactic molecular cloud regions. [CI] intensities are lower than, but nevertheless comparable to J=4-3 12CO intensities, again rather different from Galactic sources. The ratio of [CI] to 13CO increases with the central [CI] luminosity of a galaxy; it is lowest for quiescent and mild starburst centers, and highest for strong starburst centers and active nuclei. Comparison with radiative transfer model calculations shows that most observed galaxy centers have neutral carbon abundances close to, or exceeding, carbon monoxide abundances, rather independent from the assumed model gas parameters. The same models suggest that the emission from neutral carbon and carbon monoxide, if assumed to originate in the same volumes, arises from a warm and dense gas rather than a hot and tenuous, or a cold and very dense gas. The observed [CI] intensities together with literature [CII] line and far-infrared continuum data likewise suggest that a significant fraction of the emission originates in medium-density gas (n = 10**3 - 10**4 cm**-3, subjected to radiation fields of various strengths.
CI and CO in the Spiral Galaxies NGC 6946 and M 83
F. P. Israel,F. Baas
Physics , 2001, DOI: 10.1051/0004-6361:20010354
Abstract: Multitransition 12CO, 13CO and 492 GHz [CI] measurements of the late-type spiral galaxies NGC 6946 and M 83 (NGC 5236) show pronounced molecular gas concentrations in rapid solid-body rotation within a few hundred parsec from both nuclei. Their 12CO, 13CO and [CI] relative intensities are nearly identical. However, the very different [CII] intensities imply that the physical conditions are not. The slow decrease of 12CO intensities with increasing rotational level marks the presence of significant amounts of warm and dense molecular gas in both galaxy centers. Detailed modelling indicates that both galaxiy centers contain at least two distinct molecular components: a warm and dense component with T(kin) = 30-60 K, n(H2) = 3000-10 000 cc, and a more tenuous hotter component with T(kin) = 100-150 K, n(H2) < 1000 cc). Atomic carbon column densities exceed CO column densities by a factor of about 1.5 in NGC 6946 and about 4 in M 83. Unlike NGC 6946, M 83 contains a significant amount of molecular hydrogen associated with ionized carbon rather than CO. The centers of NGC 6946 and M 83 contain nearly identical total (atomic and molecular) gas masses of about 3 x 10**7 M(sun). Despite their prominence, the central gas concentrations in these galaxies represent only a few per cent of the stellar mass in the same volume. The peak face-on gas mass density is much higher in M 83 (120 M(sun)/pc**2) than in NGC 6946 (45 M(sun)/pc**2). The more intense starburst in M 83 is associated with a more compact and somewhat hotter PDR zone than the milder starburst in NGC 6946.
Institutional trust and alcohol consumption in Sweden: The Swedish National Public Health Survey 2006
Johanna Ahnquist, Martin Lindstr?m, Sarah P Wamala
BMC Public Health , 2008, DOI: 10.1186/1471-2458-8-283
Abstract: Data from the 2006 Swedish National Survey of Public Health were used for analyses. The total study population comprised a randomly selected representative sample of 26.305 men and 30.584 women aged 16–84 years. Harmful alcohol consumption was measured using a short version the Alcohol Use Disorders Identification Test (AUDIT), developed and recommended by the World Health Organisation. Low institutional trust was defined based on trust in ten main welfare institutions in Sweden.Independent of age, country of birth and socioeconomic circumstances, low institutional trust was associated with increased likelihood of harmful alcohol consumption (OR (men) = 1.52, 95% CI 1.34–1.70) and (OR (women) = 1.50, 95% CI 1.35–1.66). This association was marginally altered after adjustment for interpersonal trust.Findings of the present study show that lack of trust in institutions is associated with increased likelihood of harmful alcohol consumption. We hope that findings in the present study will inspire similar studies in other contexts and contribute to more knowledge on the association between institutional trust and lifestyle patterns. This evidence may contribute to policies and strategies related to alcohol consumption.Social capital entails civic engagement, social participation, trust in other people, trust in the formal institutions of society and generalized reciprocity[1]. Some authors have studied social capital as contextual characteristics of society [2,3], while others have investigated it from a micro-level perspective. Thus social capital in previous studies entails both social relations in the local environment and trust between individuals [4,5]. Social capital has often been operationalized as social participation and trust [1], but these two core components of social capital are not strongly correlated [6]. Trust includes the expectation that an individual or institution will act competently, fairly, openly, and with concern [7,8].In the literature there ha
Knotworking in Academic Libraries: Two Case Studies from the University of Helsinki
Yrj? Engestr?m,Heli Kaatrakoski,P?lvi Kaiponen,Johanna Lahikainen
Liber Quarterly : The Journal of European Research Libraries , 2012,
Abstract: Librarians in academic libraries are facing major changes in their work due to, e.g., the internet, digitization, and increasing use of new channels for information retrieval by their most important clients, namely researchers. This creates challenges for librarians: both to deepen their own expertise and to develop innovative service models for their clients. In this paper we present a development project entitled ‘Knotworking in the Library’ from the Helsinki University Library. The project made use of the Change Laboratory method, which is an intensive developmental effort which facilitates improvements in the activities of organizations and changes in the organizational culture. The process started in Viikki Campus Library in 2009–2010 and continued in the City Centre Campus Library in 2010–2011. The aim was to create new kinds of partnership between libraries and research groups in the form of knotworking. By knotworking we mean a boundary-crossing, collective problem-solving way of organizing work. The knotworking model presented in this paper generated practical tools to assist selected research groups in dealing with data management related-issues.
Monitoring the T-Cell Receptor Repertoire at Single-Clone Resolution
Hendrik P.J. Bonarius, Frank Baas, Ester B.M. Remmerswaal, René A.W. van Lier, Ineke J.M. ten Berge, Paul P. Tak, Niek de Vries
PLOS ONE , 2006, DOI: 10.1371/journal.pone.0000055
Abstract: The adaptive immune system recognizes billions of unique antigens using highly variable T-cell receptors. The αβ T-cell receptor repertoire includes an estimated 106 different rearranged β chains per individual. This paper describes a novel micro-array based method that monitors the β chain repertoire with a resolution of a single T-cell clone. These T-arrays are quantitative and detect T-cell clones at a frequency of less than one T cell in a million, which is 2 logs more sensitive than spectratyping (immunoscope), the current standard in repertoire analysis. Using T-arrays we detected CMV-specific CD4+ and CD8+ T-cell clones that expanded early after viral antigen stimulation in vitro and in vivo. This approach will be useful in monitoring individual T-cell clones in diverse experimental settings, and in identification of T-cell clones associated with infectious disease, autoimmune disease and cancer.
Page 1 /532093
Display every page Item

Copyright © 2008-2017 Open Access Library. All rights reserved.