The role of thermal and non-thermal processes in the ISM of the Magellanic Clouds

Radio continuum emission is a dust-unbiased tracer of both thermal and non-thermal processes in the interstellar medium. We present new maps of the free–free and synchrotron emission in the Magellanic Clouds (MCs) at 0.166, 1.4, and 4.8 GHz with no prior assumption about the radio non-thermal spectrum. The maps were constructed using a de-reddened H α map as a template for the thermal radio emission, which we subtract from maps of the total radio continuum emission. To de-redden the H α emission, it is important to know the fraction of dust surface density that attenuates the H α emission along the line of sight, fd. This fraction is obtained by comparing the dust opacity obtained through the infrared emission spectrum and the Balmer decrement method. In star-forming regions, the median fd is about 0.1, which is lower than that in diffuse regions by a factor of three. We obtain a global thermal radio fraction, fth, of 30 per cent (35 per cent) in the LMC (SMC) at 1.4 GHz. Furthermore, we present maps of the equipartition magnetic field strength with average values of ≃10.1μG in the LMC and ≃5.5μG in the SMC. The magnetic field is proportional to the star-formation rate to the power of 0.24 and 0.20 for the LMC and SMC, respectively. This study shows that non-thermal processes control the interstellar medium in the MCs

Stellar Feedback and Resolved Stellar IFU Spectroscopy in the nearby Spiral Galaxy NGC 300

We present MUSE Integral Field Unit (IFU) observations of five individual HII regions in two giant (> 100 pc in radius) star-forming complexes in the low-metallicity (Z~0.33 Z) nearby (D ~ 2 Mpc) dwarf spiral galaxy NGC 300. We combine the IFU data with high spatial resolution HST photometry to demonstrate the extraction of stellar spectra and the classification of individual stars from ground-based data at the distance of 2 Mpc. For the two star-forming complexes, in which no O-type stars had previously been identified, we find a total of 13 newly identified O-type stars in the mass range 15-50 M, as well as 4 Wolf-Rayet stars. We use the derived massive stellar content to analyze the impact of stellar feedback on the HII regions. As already found for HII regions in the Magellanic Clouds, the dynamics of the analyzed NGC 300 HII regions are dominated by a combination of the pressure of the ionized gas and stellar winds. By comparing the derived ionized gas mass loading factors to the total gas mass loading factor across the NGC 300 disk, we find that the latter is an order of magnitude higher, either indicating very early evolutionary stages for these HII regions, or being a direct result of the multi-phase nature of feedback-driven bubbles. Moreover, we analyze the relation between the star formation rate and the pressure of the ionized gas as derived from small (<100 pc) scales, as both quantities are systematically overestimated when derived on galactic scales. With the wealth of ongoing and upcoming IFU instruments and programs, this study serves as a pathfinder for the systematic investigation of resolved stellar feedback in nearby galaxies, and it delivers the necessary analysis tools to enable massive stellar content and feedback studies sampling an unprecedented range of HII region properties across entire galaxies in the nearby Universe

Dose-response model of murine typhus (Rickettsia typhi): time post inoculation and host age dependency analysis

<p>Abstract</p> <p>Background</p> <p><it>Rickettsia typhi (R. mooseri) </it>is the causative agent of murine typhus. It is one of the most widely distributed flea-borne diseases with a relatively mild febrile initial illness with six to 14 days of incubation period. The bacterium is gram negative and an obligate intracellular pathogen. The disease is transmitted to humans and vertebrate host through fleabites or via contact with infected feces. This paper develops dose-response models of different routes of exposure for typhus in rodents.</p> <p>Methods</p> <p>Data from published articles were analyzed using parametric dose-response relationship models. Dose-response relationships were fit to data using the method of maximum likelihood estimation (MLE).</p> <p>Results</p> <p>Dose-response models quantifying the effects of different ages of rats and time post inoculation in BALB/c mice were analyzed in the study. Both the adult rats (inoculated intradermally) and newborn rats (inoculated subcutaneously) were best fit by exponential models and both distributions could be described by a single dose-response relationship. The BALB/C mice inoculated subcutaneously were best fit by Beta-Poisson models. The time post inoculation analysis showed that there was a definite time and response relationship existed in this case.</p> <p>Conclusions</p> <p>Intradermally or subcutaneously inoculated rats (adult and newborn) models suggest that less than 1 plaque-forming unit (PFU) (1.33 to 0.38 in 95% confidence limits) of the pathogen is enough to seroconvert 50% of the exposed population on average. For the BALB/c mouse time post inoculation model, an average dose of 0.28 plaque-forming units (PFU) (0.75 to 0.11 in 95% confidence limits) will seroconvert 50% of the exposed mice.</p

The impact of pre-supernova feedback and its dependence on environment

Integral field units enable resolved studies of a large number of star-forming regions across entire nearby galaxies, providing insight on the conversion of gas into stars and the feedback from the emerging stellar populations over unprecedented dynamic ranges in terms of spatial scale, star-forming region properties, and environments. We use the VLT/MUSE legacy data set covering the central $35$ arcmin$^{2}$ (${\sim}12$ kpc$^{2}$) of the nearby galaxy NGC 300 to quantify the effect of stellar feedback as a function of the local galactic environment. We extract spectra from emission line regions identified within dendrograms, combine emission line ratios and line widths to distinguish between HII regions, planetary nebulae, and supernova remnants, and compute their ionised gas properties, gas-phase oxygen abundances, and feedback-related pressure terms. For the HII regions, we find that the direct radiation pressure ($P_\mathrm{dir}$) and the pressure of the ionised gas ($P_{HII}$) weakly increase towards larger galactocentric radii, i.e. along the galaxy's (negative) abundance and (positive) extinction gradients. While the increase of $P_{HII}$ with galactocentric radius is likely due to higher photon fluxes from lower-metallicity stellar populations, we find that the increase of $P_\mathrm{dir}$ is likely driven by the combination of higher photon fluxes and enhanced dust content at larger galactocentric radii. In light of the above, we investigate the effect of increased pre-supernova feedback at larger galactocentric distances (lower metallicities and increased dust mass surface density) on the ISM, finding that supernovae at lower metallicities expand into lower-density environments, thereby enhancing the impact of supernova feedback

Vaccines against toxoplasma gondii : challenges and opportunities

Development of vaccines against Toxoplasma gondii infection in humans is of high priority, given the high burden of disease in some areas of the world like South America, and the lack of effective drugs with few adverse effects. Rodent models have been used in research on vaccines against T. gondii over the past decades. However, regardless of the vaccine construct, the vaccines have not been able to induce protective immunity when the organism is challenged with T. gondii, either directly or via a vector. Only a few live, attenuated T. gondii strains used for immunization have been able to confer protective immunity, which is measured by a lack of tissue cysts after challenge. Furthermore, challenge with low virulence strains, especially strains with genotype II, will probably be insufficient to provide protection against the more virulent T. gondii strains, such as those with genotypes I or II, or those genotypes from South America not belonging to genotype I, II or III. Future studies should use animal models besides rodents, and challenges should be performed with at least one genotype II T. gondii and one of the more virulent genotypes. Endpoints like maternal-foetal transmission and prevention of eye disease are important in addition to the traditional endpoint of survival or reduction in numbers of brain cysts after challenge

Transient Receptor Potential (TRP) and Cch1-Yam8 Channels Play Key Roles in the Regulation of Cytoplasmic Ca2+ in Fission Yeast

The regulation of cytoplasmic Ca2+ is crucial for various cellular processes. Here, we examined the cytoplasmic Ca2+ levels in living fission yeast cells by a highly sensitive bioluminescence resonance energy transfer-based assay using GFP-aequorin fusion protein linked by 19 amino acid. We monitored the cytoplasmic Ca2+ level and its change caused by extracellular stimulants such as CaCl2 or NaCl plus FK506 (calcineurin inhibitor). We found that the extracellularly added Ca2+ caused a dose-dependent increase in the cytoplasmic Ca2+ level and resulted in a burst-like peak. The overexpression of two transient receptor potential (TRP) channel homologues, Trp1322 or Pkd2, markedly enhanced this response. Interestingly, the burst-like peak upon TRP overexpression was completely abolished by gene deletion of calcineurin and was dramatically decreased by gene deletion of Prz1, a downstream transcription factor activated by calcineurin. Furthermore, 1 hour treatment with FK506 failed to suppress the burst-like peak. These results suggest that the burst-like Ca2+ peak is dependent on the transcriptional activity of Prz1, but not on the direct TRP dephosphorylation. We also found that extracellularly added NaCl plus FK506 caused a synergistic cytosolic Ca2+ increase that is dependent on the inhibition of calcineurin activity, but not on the inhibition of Prz1. The synergistic Ca2+ increase is abolished by the addition of the Ca2+ chelator BAPTA into the media, and is also abolished by deletion of the gene encoding a subunit of the Cch1-Yam8 Ca2+ channel complex, indicating that the synergistic increase is caused by the Ca2+ influx from the extracellular medium via the Cch1-Yam8 complex. Furthermore, deletion of Pmk1 MAPK abolished the Ca2+ influx, and overexpression of the constitutively active Pek1 MAPKK enhanced the influx. These results suggest that Pmk1 MAPK and calcineurin positively and negatively regulate the Cch1-Yam8 complex, respectively, via modulating the balance between phosphorylation and dyphosphorylation state

Case Management as a Significant Component of Usual Care Psychotherapy for Youth with Disruptive Behavior Problems

Youth with disruptive behavior problems (DBPs) represent the majority of youth served in usual care (UC) psychotherapy, and are at high risk for maladaptive outcomes. Little is known about UC psychotherapeutic strategies utilized with this population. Researchers and clinicians suggest that case management (CM) is a major activity occurring in usual care. CM includes coordinating care with service providers and individuals, including schools, psychiatrists, and community-based services. This study assesses the prevalence and predictors of clinician use of CM in usual care. Results from this study suggest that CM is frequently used in UC psychotherapy with youth with DBPs. The extent of use of CM in UC may have implications for implementation of evidence-based practices in usual care psychotherapy

Differential susceptibility in youth: evidence that 5-HTTLPR x positive parenting is associated with positive affect ‘for better and worse'

Positive affect has been implicated in the phenomenological experience of various psychiatric disorders, vulnerability to develop psychopathology and overall socio-emotional functioning. However, developmental influences that may contribute to positive affect have been understudied. Here, we studied youths' 5-HTTLPR genotype and rearing environment (degree of positive and supportive parenting) to investigate the differential susceptibility hypothesis (DSH) that youth carrying short alleles of 5-HTTLPR would be more influenced and responsive to supportive and unsupportive parenting, and would exhibit higher and lower positive affect, respectively. Three independent studies tested this gene–environment interaction (GxE) in children and adolescents (age range 9–15 years; total N=1874). In study 1 (N=307; 54% girls), positive/supportive parenting was assessed via parent report, in study 2 (N=197; 58% girls) via coded observations of parent–child interactions in the laboratory and in study 3 (N=1370; 53% girls) via self report. Results from all the three studies showed that youth homozygous for the functional short allele of 5-HTTLPR were more responsive to parenting as environmental context in a ‘for better and worse' manner. Specifically, the genetically susceptible youth (that is, S'S' group) who experienced unsupportive, non-positive parenting exhibited low levels of positive affect, whereas higher levels of positive affect were reported by genetically susceptible youth under supportive and positive parenting conditions. These GxE findings are consistent with the DSH and may inform etiological models and interventions in developmental psychopathology focused on positive emotion, parenting and genetic susceptibility

Causal Network Accounts Of Ill-being: Depression & Digital Well-being

Depression is a common and devastating instance of ill-being which deserves an account. Moreover, the ill-being of depression is impacted by digital technology: some uses of digital technology increase such ill-being while other uses of digital technology increase well-being. So a good account of ill-being would explicate the antecedents of depressive symptoms and their relief, digitally and otherwise. This paper borrows a causal network account of well-being and applies it to ill-being, particularly depression. Causal networks are found to provide a principled, coherent, intuitively plausible, and empirically adequate account of cases of depression in every-day and digital contexts. Causal network accounts of ill-being also offer philosophical, scientific, and practical utility. Insofar as other accounts of ill-being cannot offer these advantages, we should prefer causal network accounts of ill-being