SLUG IV: a novel forward-modelling method to derive the demographics of star clusters

We describe a novel method for determining the demographics of a population of star clusters, for example distributions of cluster mass and age, from unresolved photometry. This method has a number of desirable properties: it fully exploits all the information available in a data set without any binning, correctly accounts for both measurement error and sample incompleteness, naturally handles heterogenous data (e.g. fields that have been imaged with different sets of filters or to different depths), marginalizes over uncertain extinctions, and returns the full posterior distributions of the parameters describing star cluster demographics. We demonstrate the method using mock star cluster catalogues and show that our method is robust and accurate, and that it can recover the demographics of star cluster populations significantly better than traditional fitting methods. For realistic sample sizes, our method is sufficiently powerful that its accuracy is ultimately limited by the accuracy of the underlying physical models for stellar evolution and interstellar dust, rather than by statistical uncertainties. Our method is implemented as part of the Stochastically Lighting Up Galaxies (SLUG) stellar populations code, and is freely available.MRK acknowledges support from the Australian Research Council’s Discovery Projects funding scheme (project DP160100695) and from NASA through grants from the Space Telescope Science Institute research (program numbers 13256 and 13364

Venous thromboembolism and chronic venous disease among people who inject drugs: A systematic review and meta-analysis

Introduction Intravenous drug use continues to pose a substantial burden worldwide and little is known about the risk of venous thromboembolism (VTE) and its sequelae in people who inject drugs (PWID). Methods A systematic literature search was conducted on the prevalence of VTE and chronic venous disease in intravenous drug users, as well as on the prevalence of intravenous drug use among selected VTE patients. Two reviewers independently selected the articles and appraised their quality. A random-effect meta-analysis was performed to pool risks across studies. Results We included 18 studies with a total of 7691 patients. The overall prevalence of VTE among PWID was 29% (95%CI: 19–40%). Among patients diagnosed with VTE, 15% (95%CI: 10–20%) were PWID. Similar rates were confirmed in more recent studies published in the past decade, although these studies are often based on the general population from higher-risk areas. Reported rates of chronic venous disease ranged between 58% and 61%. The majority of the included studies had a low to moderate quality of evidence. We could not exclude a selection bias in the studies in geographical regions with high intravenous drug use prevalence. Conclusion VTE and chronic venous disease appear to be common and understudied complications of injective drug use. National programs for PWID patients should also focus on early and late VTE-associated complications

Preparation and Characterization of a Novel Skin Substitute

Autologous epidermal cell cultures (CEA) represent a possibility to treat extensive burn lesions, since they allow a significative surface expansion which cannot be achieved with other surgical techniques based on autologous grafting. Moreover currently available CEA preparations are difficult to handle and their take rate is unpredictable. This study aimed at producing and evaluating a new cutaneous biosubstitute made up of alloplastic acellular glycerolized dermis (AAGD) and CEA to overcome these difficulties. A procedure that maintained an intact basement membrane was developed, so as to promote adhesion and growth of CEA on AAGD. Keratinocytes were seeded onto AAGD and cultured up to 21 days. Viability tests and immunohistochemical analysis with specific markers were carried out at 7, 14, and 21 days, to evaluate keratinocyte adhesion, growth, and maturation. Our results support the hypothesis that this newly formed skin substitute could allow its permanent engraftment in clinical application

miRNA expression is increased in serum from patients with semantic variant primary progressive aphasia

Primary progressive aphasia (PPA) damages the parts of the brain that control speech and language. There are three clinical PPA variants: nonfluent/agrammatic (nfvPPA), logopenic (lvPPA) and semantic (svPPA). The pathophysiology underlying PPA variants is not fully understood, including the role of micro (mi)RNAs which were previously shown to play a role in several neurodegenerative diseases. Using a two-step analysis (array and validation through real-time PCR), we investigated the miRNA expression pattern in serum from 54 PPA patients and 18 controls. In the svPPA cohort, we observed a generalized upregulation of miRNAs with miR-106b-5p and miR-133a-3p reaching statistical significance (miR-106b-5p: 2.69 ± 0.89 mean ± SD vs. 1.18 ± 0.28

PRNP P39L variant is a rare cause of frontotemporal dementia in Iialian population

The missense P39L variant in the prion protein gene (PRNP) has recently been associated with frontotemporal dementia (FTD). Here, we analyzed the presence of the P39L variant in 761 patients with FTD and 719 controls and found a single carrier among patients. The patient was a 67-year-old male, with a positive family history for dementia, who developed apathy, short term memory deficit, and postural instability at 66. Clinical and instrumental workup excluded prion disease. At MRI, bilateral frontal lobe atrophy was present. A diagnosis of FTD was made, with a mainly apathetic phenotype. The PRNP P39L mutation may be an extremely rare cause of FTD (0.13%)

Modeling the Effects of Star Formation Histories on Halpha and Ultra-Violet Fluxes in Nearby Dwarf Galaxies

We consider the effects of non-constant star formation histories (SFHs) on Halpha and GALEX far ultra-violet (FUV) star formation rate (SFR) indicators. Under the assumption of a fully populated Chabrier IMF, we compare the distribution of Halpha-to-FUV flux ratios from ~ 1500 simple, periodic model SFHs with observations of 185 galaxies from the Spitzer Local Volume Legacy survey. We find a set of SFH models that are well matched to the data, such that more massive galaxies are best characterized by nearly constant SFHs, while low mass systems experience bursts amplitudes of ~ 30 (i.e., an increase in the SFR by a factor of 30 over the SFR during the inter-burst period), burst durations of tens of Myr, and periods of ~ 250 Myr; these SFHs are broadly consistent with the increased stochastic star formation expected in systems with lower SFRs. We analyze the predicted temporal evolution of galaxy stellar mass, R-band surface brightness, Halpha-derived SFR, and blue luminosity, and find that they provide a reasonable match to observed flux distributions. We find that our model SFHs are generally able to reproduce both the observed systematic decline and increased scatter in Halpha-to-FUV ratios toward low mass systems, without invoking other physical mechanisms. We also compare our predictions with those from the Integrated Galactic IMF theory with a constant SFR. We find that while both predict a systematic decline in the observed ratios, only the time variable SFH models are capable of producing the observed population of low mass galaxies ($M_{*}$ < 10$^{7}$ Msun) with normal Halpha-to-FUV ratios. These results demonstrate that a variable IMF alone has difficulty explaining the observed scatter in the Halpha-to-FUV ratios. We conclude by considering the limitations of the model SFHs, and discuss the use of additional empirical constraints to improve future SFH modeling efforts.Comment: 15 pages, 11 Figures. Accepted for publication in Ap

Critical issues for the proper diagnosis of Metachromatic Leukodystrophy

n/

LEVANTAMENTO DO USO DE PLANTAS MEDICINAIS NA UNIVERSIDADE FEDERAL DO PARANÁ, PALOTINA – PR, BRASIL

As plantas medicinais representam uma alternativa de tratamento e/ou de prevenção de doenças de grande importância na vida das pessoas, não somente por sua eficácia na ação terapêutica, mas também por se inserir simultaneamente como parte da cultura de um povo. Neste contexto, o presente trabalho teve como objetivo realizar um levantamento do uso das plantas medicinais entre os funcionários da Universidade Federal do Paraná, Palotina, Paraná, Brasil. Foram aplicados questionários semiestruturados sobre a utilização de plantas medicinais aos docentes, técnico-administrativos e funcionários terceirizados responsáveis pela manutenção da estrutura, jardins e da limpeza da universidade, totalizando 107 entrevistados. Detectou-se que 72% fazem uso de plantas medicinais, sendo que a maioria utiliza por ser um produto natural e que obtiveram o conhecimento a partir da tradição familiar. A cidreira, hortelã, boldo, camomila, guaco e a marcela foram as plantas citadas como mais utilizadas, e o resfriado, a gripe, cólicas e a enxaqueca como a doença e/ou mal estar mais frequentemente tratados com plantas medicinais. A partir dos resultados foram planejadas atividades de extensão, como palestras, dinâmicas, práticas e visitas ao horto medicinal da universidade. As atividades foram direcionadas numa primeira fase às funcionárias responsáveis pela limpeza, uma vez que preparavam chás diariamente para os demais envolvidos no estudo. A troca de saberes, a aquisição de novos conhecimentos e a interação entre alunos, professores e o público-alvo envolvido foram os aspectos mais evidentes durante as atividades realizadas, contribuindo para a formação dos alunos e a melhoria da qualidade de vida das pessoas