No Excess of RR Lyrae Stars in the Canis Major Overdensity

Our multi-epoch survey of ~20 sq. deg. of the Canis Major overdensity has detected only 10 RR Lyrae stars (RRLS). We show that this number is consistent with the number expected from the Galactic halo and thick disk populations alone, leaving no excess that can be attributed to the dwarf spheroidal (dSph) galaxy that some authors have proposed as the origin of the CMa overdensity. If this galaxy resembles the dSph satellites of the Milky Way and of M31 and has the putative Mv~-14.5, our survey should have detected several tens of RRLS. Even if Mv10, which is not observed. Either the old stellar population of this galaxy has unique properties or, as others have argued before, the CMa overdensity is produced by the thin and thick disk and spiral arm populations of the Milky Way and not by a collision with a dSph satellite galaxy.Comment: 35 pages, 9 figures, 5 tables. Accepted for publication at the Astronomical Journa

The massive stellar content in NGC604 and its evolutionary state

The ultraviolet resonance wind stellar lines, the nebular optical emission lines and the higher order terms of the Balmer series and HeI absorption lines detected in the spectra of NGC 604 are interpreted using evolutionary models optimized for young star forming regions. The evolutionary state and the massive stellar content of the region is derived in a self-consistent way. The three techniques applied suggest that the central ionizing cluster in NGC 604 is very young, 3 Myr old, and that the stars in the cluster were formed in an instantaneous burst following a Salpeter or flatter IMF, having stars more massive that 80 Msol. The stellar cluster is able to provide most of the ionizing photons needed to photoionize the whole nebula, and the wind power to form the central shell structure where the cluster core is located. The stellar cluster is affected by an extinction similar to the average extinction that affects the ionized gas. The estimated number of massive stars in the cluster is also in agreement with that derived from previous studies based on the detection of individual stars. The results that we present here support the use of these techniques for the interpretation of the integrated light of more distant star forming regionsComment: To be published in MNRAS. 17 pages and 17 figure

Seeking order amidst chaos: a systematic review of classification systems for causes of stillbirth and neonatal death, 2009-2014.

BACKGROUND: Each year, about 5.3 million babies die in the perinatal period. Understanding of causes of death is critical for prevention, yet there is no globally acceptable classification system. Instead, many disparate systems have been developed and used. We aimed to identify all systems used or created between 2009 and 2014, with their key features, including extent of alignment with the International Classification of Diseases (ICD) and variation in features by region, to inform the World Health Organization's development of a new global approach to classifying perinatal deaths. METHODS: A systematic literature review (CINAHL, EMBASE, Medline, Global Health, and PubMed) identified published and unpublished studies and national reports describing new classification systems or modifications of existing systems for causes of perinatal death, or that used or tested such systems, between 2009 and 2014. Studies reporting ICD use only were excluded. Data were independently double-extracted (except from non-English publications). Subgroup analyses explored variation by extent and region. RESULTS: Eighty-one systems were identified as new, modifications of existing systems, or having been used between 2009 and 2014, with an average of ten systems created/modified each year. Systems had widely varying characteristics: (i) comprehensiveness (40 systems classified both stillbirths and neonatal deaths); (ii) extent of use (systems were created in 28 countries and used in 40; 17 were created for national use; 27 were widely used); (iii) accessibility (three systems available in e-format); (iv) underlying cause of death (64 systems required a single cause of death); (v) reliability (10 systems tested for reliability, with overall Kappa scores ranging from .35-.93); and (vi) ICD alignment (17 systems used ICD codes). Regional databases were not searched, so system numbers may be underestimated. Some non-differential misclassification of systems was possible. CONCLUSIONS: The plethora of systems in use, and continuing system development, hamper international efforts to improve understanding of causes of death. Recognition of the features of currently used systems, combined with a better understanding of the drivers of continued system creation, may help the development of a truly effective global system.The Mater Research Institute, University of Queensland, AustraliaThis is the final version of the article. It first appeared from BioMed Central via http://dx.doi.org/10.1186/s12884-016-1071-

Classification systems for causes of stillbirth and neonatal death, 2009-2014: an assessment of alignment with characteristics for an effective global system.

BACKGROUND: To reduce the burden of 5.3 million stillbirths and neonatal deaths annually, an understanding of causes of deaths is critical. A systematic review identified 81 systems for classification of causes of stillbirth (SB) and neonatal death (NND) between 2009 and 2014. The large number of systems hampers efforts to understand and prevent these deaths. This study aimed to assess the alignment of current classification systems with expert-identified characteristics for a globally effective classification system. METHODS: Eighty-one classification systems were assessed for alignment with 17 characteristics previously identified through expert consensus as necessary for an effective global system. Data were extracted independently by two authors. Systems were assessed against each characteristic and weighted and unweighted scores assigned to each. Subgroup analyses were undertaken by system use, setting, type of death included and type of characteristic. RESULTS: None of the 81 systems were aligned with more than 9 of the 17 characteristics; most (82 %) were aligned with four or fewer. On average, systems were aligned with 19 % of characteristics. The most aligned system (Frøen 2009-Codac) still had an unweighted score of only 9/17. Alignment with individual characteristics ranged from 0 to 49 %. Alignment was somewhat higher for widely used as compared to less used systems (22 % v 17 %), systems used only in high income countries as compared to only in low and middle income countries (20 % vs 16 %), and systems including both SB and NND (23 %) as compared to NND-only (15 %) and SB-only systems (13 %). Alignment was higher with characteristics assessing structure (23 %) than function (15 %). CONCLUSIONS: There is an unmet need for a system exhibiting all the characteristics of a globally effective system as defined by experts in the use of systems, as none of the 81 contemporary classification systems assessed was highly aligned with these characteristics. A particular concern in terms of global effectiveness is the lack of alignment with "ease of use" among all systems, including even the most-aligned. A system which meets the needs of users would have the potential to become the first truly globally effective classification system.The Mater Research Institute of the University of Queensland, AustraliaThis is the final version of the article. It first appeared from BioMed Central via http://dx.doi.org/10.1186/s12884-016-1040-

A Smoking Gun in the Carina Nebula

The Carina Nebula is one of the youngest, most active sites of massive star formation in our Galaxy. In this nebula, we have discovered a bright X-ray source that has persisted for ~30 years. The soft X-ray spectrum, consistent with kT ~128 eV blackbody radiation with mild extinction, and no counterpart in the near- and mid-infrared wavelengths indicate that it is a ~1e6-year-old neutron star housed in the Carina Nebula. Current star formation theory does not suggest that the progenitor of the neutron star and massive stars in the Carina Nebula, in particular Eta Carinae, are coeval. This result suggests that the Carina Nebula experienced at least two major episodes of massive star formation. The neutron star may be responsible for remnants of high energy activity seen in multiple wavelengths.Comment: 9 pages, 3 figures, accepted for publication to ApJ

Levels, timing, and etiology of stillbirths in Sylhet district of Bangladesh

<p>Abstract</p> <p>Background</p> <p>Lack of data is a critical barrier to addressing the problem of stillbirth in countries with the highest stillbirth burden. Our study objective was to estimate the levels, types, and causes of stillbirth in rural Sylhet district of Bangladesh.</p> <p>Methods</p> <p>A complete pregnancy history was taken from all women (n = 39 998) who had pregnancy outcomes during 2003-2005 in the study area. Verbal autopsy data were obtained for all identified stillbirths during the period. We used pre-defined case definitions and computer programs to assign causes of stillbirth for selected causes containing specific signs and symptoms. Both non-hierarchical and hierarchical approaches were used to assign causes of stillbirths.</p> <p>Results</p> <p>A total of 1748 stillbirths were recorded during 2003-2005 from 48,192 births (stillbirth rate: 36.3 per 1000 total births). About 60% and 40% of stillbirths were categorized as antepartum and intrapartum, respectively. Maternal conditions, including infections, hypertensive disorders, and anemia, contributed to about 29% of total antepartum stillbirths. About 50% of intrapartum stillbirths were attributed to obstetric complications. Maternal infections and hypertensive disorders contributed to another 11% of stillbirths. A cause could not be assigned in nearly half (49%) of stillbirths.</p> <p>Conclusion</p> <p>The stillbirth rate is high in rural Bangladesh. Based on algorithmic approaches using verbal autopsy data, a substantial portion of stillbirths is attributable to maternal conditions and obstetric complications. Programs need to deliver community-level interventions to prevent and manage maternal complications, and to develop strategies to improve access to emergency obstetric care. Improvements in care to avert stillbirth can be accomplished in the context of existing maternal and child health programs. Methodological improvements in the measurement of stillbirths, especially causes of stillbirths, are also needed to better define the burden of stillbirths in low-resource settings.</p

Characteristics of a global classification system for perinatal deaths: a Delphi consensus study.

BACKGROUND: Despite the global burden of perinatal deaths, there is currently no single, globally-acceptable classification system for perinatal deaths. Instead, multiple, disparate systems are in use world-wide. This inconsistency hinders accurate estimates of causes of death and impedes effective prevention strategies. The World Health Organisation (WHO) is developing a globally-acceptable classification approach for perinatal deaths. To inform this work, we sought to establish a consensus on the important characteristics of such a system. METHODS: A group of international experts in the classification of perinatal deaths were identified and invited to join an expert panel to develop a list of important characteristics of a quality global classification system for perinatal death. A Delphi consensus methodology was used to reach agreement. Three rounds of consultation were undertaken using a purpose built on-line survey. Round one sought suggested characteristics for subsequent scoring and selection in rounds two and three. RESULTS: The panel of experts agreed on a total of 17 important characteristics for a globally-acceptable perinatal death classification system. Of these, 10 relate to the structural design of the system and 7 relate to the functional aspects and use of the system. CONCLUSION: This study serves as formative work towards the development of a globally-acceptable approach for the classification of the causes of perinatal deaths. The list of functional and structural characteristics identified should be taken into consideration when designing and developing such a system.This project was initially undertaken as part of the Harmonized Reproductive Health Registries project through the Norwegian Institute of Public Health in Partnership with the Mater Medical Research Institute, Brisbane, Australia, and in collaboration with the Department of Reproductive Health and Research, WHO.This is the author accepted manuscript. It is currently under an indefinite embargo pending publication by BioMed Central

Assembly, assessment and availability of de novo generated transcriptomes

De novo assembly of a complete transcriptome without the need for a guiding reference genome is attractive, particularly where the cost and complexity of generating a eukaryote genome is prohibitive. The transcriptome should not however be seen as just a quick and cheap alternative to building a complete genome. Transcriptomics allows the understanding and comparison of spatial and temporal samples within an organism and allows surveying of multiple individuals or closely related species. De novo assembly in theory allows the building of a complete transcriptome without any prior knowledge of the genome it also allows the discovery of alternate splice forms of coding RNAs and also non-coding RNAs, which are often missed by proteomic approaches or are incompletely annotated in genome studies. The limitations of the method are that generation of a truly complete assembly is unlikely and so we require some method for assessment of the quality and appropriateness of a generated transcriptome. Whilst no single consensus pipeline or tools is agreed as optimal, various algorithms and easy to use software do exist making transcriptome generation a more common approach. With this expansion of data, questions still exist relating to how do we make these datasets fully discoverable, comparable and most useful to understand complex biological systems

Identifying Fishes through DNA Barcodes and Microarrays

Background: International fish trade reached an import value of 62.8 billion Euro in 2006, of which 44.6% are covered by the European Union. Species identification is a key problem throughout the life cycle of fishes: from eggs and larvae to adults in fisheries research and control, as well as processed fish products in consumer protection. Methodology/Principal Findings: This study aims to evaluate the applicability of the three mitochondrial genes 16S rRNA (16S), cytochrome b (cyt b), and cytochrome oxidase subunit I (COI) for the identification of 50 European marine fish species by combining techniques of ‘‘DNA barcoding’’ and microarrays. In a DNA barcoding approach, neighbour Joining (NJ) phylogenetic trees of 369 16S, 212 cyt b, and 447 COI sequences indicated that cyt b and COI are suitable for unambiguous identification, whereas 16S failed to discriminate closely related flatfish and gurnard species. In course of probe design for DNA microarray development, each of the markers yielded a high number of potentially species-specific probes in silico, although many of them were rejected based on microarray hybridisation experiments. None of the markers provided probes to discriminate the sibling flatfish and gurnard species. However, since 16S-probes were less negatively influenced by the ‘‘position of label’’ effect and showed the lowest rejection rate and the highest mean signal intensity, 16S is more suitable for DNA microarray probe design than cty b and COI. The large portion of rejected COI-probes after hybridisation experiments (.90%) renders the DNA barcoding marker as rather unsuitable for this high-throughput technology. Conclusions/Significance: Based on these data, a DNA microarray containing 64 functional oligonucleotide probes for the identification of 30 out of the 50 fish species investigated was developed. It represents the next step towards an automated and easy-to-handle method to identify fish, ichthyoplankton, and fish products