Biology and population studies of two endemic Nematoceras (orchid) species on sub-Antarctic Macquarie Island

Two endemic orchid species, Nematoceras dienemum and N. sulcatum, are known from sub-Antarctic Macquarie Island. Several additional orchid populations on the island are reported and deistogamy is documented in N. dienemum for the first time. The known population sizes, habitats and locations for both orchid species are documented here, and new information on their biology and population ecology is provided

What is current practice in offering debriefing services to post partum women and what are the perceptions of women in accessing these services: A critical review of the literature

Objective: The main research question is to describe current practice in offering debriefing services to postpartum women and learn about the perceptions of women accessing these services Design: Critical review of the literature using a meta ethnography approach. Findings: Twenty papers were identified. These included four surveys, three qualitative studies, one mixed methods study and three literature reviews. Nine randomised controlled trials (RCTs) provided additional information from alongside surveys and description of interventions. Two types of debriefing were identified: structured and unstructured. The more formal psychoanalytic forms took place within the RCTs whilst the unstructured discussion sessions commonly with midwives were identified in other research papers. In addition there is confusion amongst service providers about the nature of debriefing and what is delivered. Various aspects of providing a postnatal debriefing service were identified including the optimal timing, specific groups offered debriefing and the number of sessions offered. Postnatal debriefing enabled women to have their birth experiences validated by talking and being listened to and being provided with information. Finally from the limited literature identified relating to midwives’ perceptions of postnatal debriefing there was an overall feeling from midwives that they considered it to be beneficial to women. Key conclusions: The findings of this literature review imply that women’s responses to receiving postnatal debriefing are generally positive. This review has found that women appear to value talking and being listened to by a midwife following birth. They seem to have a strong need to have their story heard. This discussion also allows the women to have questions answered and information given where necessary. The whole process places a seal on a woman’s birth experience which is validated. Implications for practice: Although there is no evidence to suggest that postnatal debriefing reduces morbidity, women find the service of value. Maternity providers should consider offering a postnatal debriefing service to meet those needs in advance of further research in this area

A community-based geological reconstruction of Antarctic Ice Sheet deglaciation since the Last Glacial Maximum

A robust understanding of Antarctic Ice Sheet deglacial history since the Last Glacial Maximum is important in order to constrain ice sheet and glacial-isostatic adjustment models, and to explore the forcing mechanisms responsible for ice sheet retreat. Such understanding can be derived from a broad range of geological and glaciological datasets and recent decades have seen an upsurge in such data gathering around the continent and Sub-Antarctic islands. Here, we report a new synthesis of those datasets, based on an accompanying series of reviews of the geological data, organised by sector. We present a series of timeslice maps for 20ka, 15ka, 10ka and 5ka, including grounding line position and ice sheet thickness changes, along with a clear assessment of levels of confidence. The reconstruction shows that the Antarctic Ice sheet did not everywhere reach the continental shelf edge at its maximum, that initial retreat was asynchronous, and that the spatial pattern of deglaciation was highly variable, particularly on the inner shelf. The deglacial reconstruction is consistent with a moderate overall excess ice volume and with a relatively small Antarctic contribution to meltwater pulse 1a. We discuss key areas of uncertainty both around the continent and by time interval, and we highlight potential priorit. © 2014 The Authors

Mutational spectrum in a worldwide study of 29,700 families with BRCA1 or BRCA2 mutations.

The prevalence and spectrum of germline mutations in BRCA1 and BRCA2 have been reported in single populations, with the majority of reports focused on White in Europe and North America. The Consortium of Investigators of Modifiers of BRCA1/2 (CIMBA) has assembled data on 18,435 families with BRCA1 mutations and 11,351 families with BRCA2 mutations ascertained from 69 centers in 49 countries on six continents. This study comprehensively describes the characteristics of the 1,650 unique BRCA1 and 1,731 unique BRCA2 deleterious (disease-associated) mutations identified in the CIMBA database. We observed substantial variation in mutation type and frequency by geographical region and race/ethnicity. In addition to known founder mutations, mutations of relatively high frequency were identified in specific racial/ethnic or geographic groups that may reflect founder mutations and which could be used in targeted (panel) first pass genotyping for specific populations. Knowledge of the population-specific mutational spectrum in BRCA1 and BRCA2 could inform efficient strategies for genetic testing and may justify a more broad-based oncogenetic testing in some populations

Measurement of moss growth in continental Antarctica

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Measurement of moss growth in continental Antarctica

Using steel pins inserted into growing moss colonies near Casey Station, Wilkes Land, continental Antarctica, we have measured the growth rate of three moss species: Bryum pseudotriquetrum and Schistidium antarctici over 20 years and Ceratodon purpureus over 10 years. This has provided the first long-term growth measurements for plants in Antarctica, confirming that moss shoots grow extremely slowly in Antarctica, elongating between 1 and 5 mm per year. Moss growth rates are dependent on availability of water. Antheridia were observed on some stems of B. pseudotriquetrum; no archegonia or sporophytes were observed. Stems bearing antheridia elongated much more slowly than vegetative stems in the same habitat. Two other methods of growth rate measurement were tested, and gave similar rates of elongation over shorter periods of time. However, for long-term measurements, the steel pin measurements proved remarkably reproducible and reliable

New records of three moss species (Ptychostomum pseudotriquetrum, Schistidium antarctici, and Coscinodon lawianus) from the southern Prince Charles Mountains, Mac.Robertson Land, Antarctica

We have used a combination of traditional morphological examination and molecular DNA analysis to characterise 16 moss specimens collected from the Mawson Escarpment and Clemence Massif, exposures of bedrock and glacial debris in the southern Prince Charles Mountains of East Antarctica. The nuclear ribosomal ITS region and the chloroplast rps4 gene were sequenced and compared with those of other mosses known from coastal East Antarctica. The moss specimens from the southern Prince Charles Mountains were identified as Ptychostomum pseudotriquetrum (Hedw.) D. T. Holyoak and N. Pedersen, Schistidium antarctici (Cardot) 'L.I. Savicz & Smirnova' and Coscinodon lawianus (J.H. Willis) Ochyra. These constitute a new record for S. antarctici in the Prince Charles Mountains, and confirm and extend southwards previous records for P. pseudotriquetrum and C. lawianus in the region

High levels of genetic variability in the moss Ceratodon purpureus from continental Antarctica, subantarctic Heard and Macquarie Islands, and Australasia

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Genetic diversity and dispersal of the moss Sarconeurum glaciale on Ross Island, East Antarctica

The extent of genetic variation and dispersal mechanisms were investigated over short distances of 1-100 m, and up to 3 km, by the random amplified polymorphic DNA (RAPD) technique, for the moss Sarconeurum glaciale, at three locations on Ross Island, Antarctica. At Arrival Heights, genetic variation occurred within single colonies, and the relationships between clumps indicated that they were dispersed down small, meltwater drainage channels by water. The genetic similarities between the colonies from Arrival Heights and others from Scott Base and Crater Hill, a few km away, together with the prevailing wind direction and absence of this moss in the intervening snow-covered area, suggested longer-distance dispersal by wind. Overall, the Ross Island samples appeared to form a single, polymorphic population that was distinct from another population at Canada Glacier, 110 km distant. Somatic mutation, rather than immigration of genetically different propagules from elsewhere, appeared to be the most probable cause of genetic variability in these haploid, vegetatively reproducing Antarctic moss populations. Initiation of recolonization of S. glaciale across a dirt track at Arrival Heights was also investigated by RAPDs, to investigate how regrowth of mosses in disturbed areas occurred in the extreme environment of Antarctica