Herschel PACS and SPIRE spectroscopy of the Photodissociation Regions associated with S 106 and IRAS 23133+6050

Photodissociation regions (PDRs) contain a large fraction of all of the interstellar matter in galaxies. Classical examples include the boundaries between ionized regions and molecular clouds in regions of massive star formation, marking the point where all of the photons energetic enough to ionize hydrogen have been absorbed. In this paper we determine the physical properties of the PDRs associated with the star forming regions IRAS 23133+6050 and S 106 and present them in the context of other Galactic PDRs associated with massive star forming regions. We employ Herschel PACS and SPIRE spectroscopic observations to construct a full 55-650 {\mu}m spectrum of each object from which we measure the PDR cooling lines, other fine- structure lines, CO lines and the total far-infrared flux. These measurements are then compared to standard PDR models. Subsequently detailed numerical PDR models are compared to these predictions, yielding additional insights into the dominant thermal processes in the PDRs and their structures. We find that the PDRs of each object are very similar, and can be characterized by a two-phase PDR model with a very dense, highly UV irradiated phase (n $\sim$ 10^6 cm^(-3), G$_0$ $\sim$ 10^5) interspersed within a lower density, weaker radiation field phase (n $\sim$ 10^4 cm^(-3), G$_0$ $\sim$ 10^4). We employed two different numerical models to investigate the data, firstly we used RADEX models to fit the peak of the $^{12}$CO ladder, which in conjunction with the properties derived yielded a temperature of around 300 K. Subsequent numerical modeling with a full PDR model revealed that the dense phase has a filling factor of around 0.6 in both objects. The shape of the $^{12}$CO ladder was consistent with these components with heating dominated by grain photoelectric heating. An extra excitation component for the highest J lines (J > 20) is required for S 106.Comment: 20 pages, 10 figures, A&A Accepte

Towards a Robuster Interpretive Parsing

The input data to grammar learning algorithms often consist of overt forms that do not contain full structural descriptions. This lack of information may contribute to the failure of learning. Past work on Optimality Theory introduced Robust Interpretive Parsing (RIP) as a partial solution to this problem. We generalize RIP and suggest replacing the winner candidate with a weighted mean violation of the potential winner candidates. A Boltzmann distribution is introduced on the winner set, and the distribution’s parameter $T$ is gradually decreased. Finally, we show that GRIP, the Generalized Robust Interpretive Parsing Algorithm significantly improves the learning success rate in a model with standard constraints for metrical stress assignment

The characteristics of the IR emission features in the spectra of Herbig Ae stars: Evidence for chemical evolution

Herbig Ae/Be stars are a class of young pre-main sequence stellar objects of intermediate mass and are known to have varying amounts of natal cloud material still present in their direct vicinity. We characterise the IR emission bands, due to fluorescence by PAH molecules, in the spectra of Herbig Ae/Be stars and link observed variations to spatial aspects of the mid-IR emission. We analysed two PAH dominated spectra from a sample of 15 Herbig Ae/Be stars observed with Spitzer and derive profiles of the major PAH bands. The shape and the measured band characteristics show pronounced variations between the two Spitzer spectra. Those variations parallel those found between three ISO spectra of other, well-studied, Herbig Ae/Be stars. The derived profiles are compared to those from a broad sample of sources. The Spitzer and ISO spectra exhibit characteristics commonly interpreted respectively as interstellar matter-like (ISM), non-ISM-like, or a combination of the two. We argue that the PAH emission detected from the sources exhibiting a combination of ISM-like and non-ISM-like characteristics indicates the presence of two dissimilar, spatially separated, PAH families. As the shape of the individual PAH band profiles reflects the composition of the PAH molecules involved, this demonstrates that PAHs in subsequent, evolutionary linked stages of star formation are different from those in the general ISM, implying active chemistry. None of the detected PAH emission can be associated with the (unresolved) disk and is thus associated with the circumstellar cloud. This implies that chemical changes may already occur in the natal cloud and not necessarily in the disk

Effects of high CO2 and warming on a Baltic Sea microzooplankton community

Global warming and ocean acidification are among the most important stressors for aquatic ecosystems in the future. To investigate their direct and indirect effects on a near-natural plankton community, a multiple-stressor approach is needed. Hence, we set up mesocosms in a full-factorial design to study the effects of both warming and high CO2 on a Baltic Sea autumn plankton community, concentrating on the impacts on microzooplankton (MZP). MZP abundance, biomass, and species composition were analysed over the course of the experiment. We observed that warming led to a reduced time-lag between the phytoplankton bloom and an MZP biomass maximum. MZP showed a significantly higher growth rate and an earlier biomass peak in the warm treatments while the biomass maximum was not affected. Increased pCO2 did not result in any significant effects on MZP biomass, growth rate, or species composition irrespective of the temperature, nor did we observe any significant interactions between CO2 and temperature. We attribute this to the high tolerance of this estuarine plankton community to fluctuations in pCO2, often resulting in CO2 concentrations higher than the predicted end-of-century concentration for open oceans. In contrast, warming can be expected to directly affect MZP and strengthen its coupling with phytoplankton by enhancing its grazing pressure

Inzicht en toezicht: controle in de kennissamenleving

Nieuwe technieken maken het opslaan en verwerken van informatie eenvoudiger. Sterker\ud nog: ze maken de weg vrij om gegevens vast te leggen voordat duidelijk is welk inzicht\ud we eigenlijk nastreven. Toezicht wint zo terrein ten opzichte van de kennisverwerving.\ud \ud Voorbeelden van toenemend toezicht zijn elektronische dossiers over burgers,\ud informatievergaring door de politie en in private initiatieven zoals Google Earth. Deze\ud systemen maken het mogelijk om op grote schaal verbanden te ontdekken en afwijkingen op\ud te sporen, zonder dat er duidelijke kennisvragen aan vooraf gaan.\ud \ud De relatie tussen inzicht en toezicht is bepalend voor hoe we met de verzamelde kennis\ud omgaan. Ligt de nadruk daarbij op inzicht, overzicht, toezicht, of nog iets anders? Dit\ud Jaarboek Kennissamenleving 2010 stelt kritische vragen bij de alomtegenwoordige blik van\ud toezicht. Het draagt ideeën aan om deze in de toekomst anders te richten, zodat inzicht en\ud toezicht in balans kunnen blijven

Treatment for Mayer-Rokitansky-Küster-Hauser syndrome (MRKH) - Development and evaluation of a group cognitive-behavioural programme

The broad aim of this thesis was to develop and evaluate an intervention addressing the psychological sequelae of MRKH. Given that MRKH is relatively rare, distressing to those affected, and has multiple and diverse psychosocial sequelae it was clear from the out-set that any intervention would have to be multi-faceted and complex. In other words I was less preoccupied with developing a ‘pure’ intervention consisting of one ‘active ingredient’ but rather wanted to give it ‘my best shot’ and devise an intervention which would be able to address a multitude of psychological difficulties arising in the context of MRKH. A framework for the development and evaluation of complex health interventions has been published by the Medical Research Council (2002). Complex interventions are defined as those “built up from a number of components, which may act both independently and inter-dependently. The components usually include behaviours, parameters of behaviours (e g. frequency, timing), and methods of organizing and delivering those behaviours (e.g. type(s) of practitioner, setting and location). It is not easy precisely to define the “active ingredients” of a complex intervention. The framework suggests a series of five phases of investigation in the development and evaluation of such interventions, ranging from a pre-clinical or theory phase, a model development phase (phase 1), an exploratory trial phase (phase 2), a definitive randomized controlled trial phase (phase 3) and a long-term implementation phase (phase 4). The work presented in the present thesis was conducted with the MRC framework in mind and covers the first three phases. A diagrammatic representation of the MRC framework and how the chapters of the present thesis map onto the different phases is given in figure 1.2. Given the time constraints of producing a thesis, by necessity some of the work on different phases has had to happen in parallel rather than strictly sequentially. The MRC framework acknowledges this point by saying that the framework “should not be read as an inflexible “to do list” but rather as advice to apply to the extent to which it is relevant at each stage” of a given project. Chapters 2 and 3 both relate to the pre-clinical or theory phase. The aims in this phase are to assess theory and evidence that may help to identify the most promising kind of intervention and study design. In chapter 2,1 present a systematic review of the literature on psychological sequelae of MRKH addressing questions on the immediate and longer term psychological impact of being diagnosed with this condition and receiving treatment. Chapter 3 contains a narrative review of the literature on adolescent development of identity and sexual milestones with the aim of getting a better understanding of how discovery/diagnosis of MRKH affects normal development. Chapter 4 relates to the model development phase of the framework. Here I describe the development of a cognitive-behavioural model of adjustment to the diagnosis of MRKH and the treatment package based on this. Chapter 5, relates to the exploratory trial phase of the MRC framework. The aims of this phase of the development of a complex intervention are to describe the constant and variable components of a replicable intervention and a feasible protocol for comparing the intervention to an appropriate alternative. The chapter details the (a) design of and setting for the study, (b) participants’ inclusion and exclusion criteria, (c) ethical considerations, and (d) recruitment. It also provides descriptions of (i) the intervention, (ii) outcome measures and assessments, (iii) sample size, (iv) randomization, and (v) method of statistical analysis chosen. It, finally, details the findings from the randomized controlled trial, outlining (a) the flow of participants through the study, (b) participants’ characteristics at baseline, reports on the (c) quantitative results of primary and secondary outcome measures (including a qualitative component), providing a (d) discussion of the limitations of the research, with suggestions and recommendations for further research, as well as outlining its strengths and noting the issued raised by the study. Chapter 6 reports a cross-sectional comparison study of participants, non-participants and comparison women, which was run in parallel with the trial. Since very little is known from research into MRKH about the psychological functioning of women with the disorder, this chapter aims to identify how these women compare with other women in terms of levels of psychiatric problems, interpersonal problems or self-esteem. Moreover, this chapter aims to address the question of (a) how within the group of women with MRKH those who decide not to take up the offer of psychological treatment compare to those who do in terms of their psychological functioning and the related question of (b) what the characteristics of MRKH women who complete psychological treatment are and how do they compare to those of women who drop out from treatment. Finally, it addresses the question of (c) whether following psychological treatment the psychological functioning of women with MRKH becomes similar to that of women without the disorder. Chapter 7, in closing, summarises the key findings of the research and provides an overarching discussion of the issues raised by the study and goes back to the MRC framework to discuss what the definitive RCT phase and the long-term implementation phase which are not covered in this thesis, might look like

Double Neutron Star Systems and Natal Neutron Star Kicks

We study the four double neutron star systems found in the Galactic disk in terms of the orbital characteristics of their immediate progenitors and the natal kicks imparted to neutron stars. Analysis of the effect of the second supernova explosion on the orbital dynamics, combined with recent results from simulations of rapid accretion onto neutron stars lead us to conclude that the observed systems could not have been formed had the explosion been symmetric. Their formation becomes possible if kicks are imparted to the radio-pulsar companions at birth. We identify the constraints imposed on the immediate progenitors of the observed double neutron stars and calculate the ranges within which their binary characteristics (orbital separations and masses of the exploding stars) are restricted. We also study the dependence of these limits on the magnitude of the kick velocity and the time elapsed since the second explosion. For each of the double neutron stars, we derive a minimum kick magnitude required for their formation, and for the two systems in close orbits we find it to exceed 200km/s. Lower limits are also set to the center-of-mass velocities of double neutron stars, and we find them to be consistent with the current proper motion observations.Comment: 25 pages, 6 figs (9 parts), 4 tables, AASTeX, Accepted in Ap

Cost-effectiveness analysis on elderly pneumococcal vaccination in the Netherlands:Challenging the Dutch Health Council's advice

Recently, the Dutch Health Council advised on elderly pneumococcal vaccination favouring the conventional polysaccharide vaccine over the novel conjugated vaccine. This advice was strongly inspired by a cost-effectiveness analysis considered to show favourable outcomes for the polysaccharide but not for the conjugated vaccine. We argue that using the same data and methods as presented by the Health Council, a different perspective on the results leads to a conclusion that not only the polysaccharide but also the conjugated pneumococcal vaccine is cost-effective. Our alternative perspective concerns the use of realistic vaccine prices, and applying an adequate time horizon for cost-effectiveness modelling. Notably, for one-off vaccination of 65-years old elderly, in all investigated analyses, also the conjugated vaccine seems cost-effective; i.e. well below the threshold of €20,000 per quality-adjusted life year, reflecting the most stringent threshold used for vaccines in the Netherlands