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An understanding of the mechanisms that determine host and parasite relationships is a central aim in parasitology. Association of a parasite species with a host species may be influenced primarily by phylogenetic constraints that cause parasite species to co-speciate with their host species, or predominantly by ecological parameters that influence all other co-evolutionary scenarios. This study aimed to investigate the role of co-speciation as well as other co-evolutionary scenarios in influencing the assemblages of tapeworm parasites (marine cestodes) in skate hosts (Rajiformes) using a modification of the PACo (Procrustean Approach to Cophylogeny) method. The study found that phylogeny and host ecology are both significant predictors of skate–tapeworm relationships, implying that co-speciation as well as other co-evolutionary scenarios are shaping these associations. The study also investigated the key ecological parameters influencing host-switching and found that host diet, distribution depth, average body size and geographical location have a combined effect. Given the importance of parasites in ensuring healthy and stable marine ecosystems, the findings of this study have implications for conservation management worldwide.
There are roughly 25 very metal-poor (VMP; [Fe/H] < -2.0), highly r-process-enhanced (‘r-II’; [Eu/Fe] > + 1.0) stars currently known, discovered over the past 20+ years. These stars provide nearly pure signatures of r-process events early in the Galactic history. We are conducting a high-resolution follow-up survey of RAVE and other bright targets to identify a total of > 100 r-II stars. Our pilot runs on the du Pont 2.5-m at Las Campanas Observatory and the ARC 3.5-m at Apache Point Observatory have already identified up to fourteen new r-II stars. We are continuing our high-resolution follow-up efforts to constrain the astrophysical site(s) and nature of the r-process.
We report the results of abundance analysis for high-resolution spectra of eight extremely metal-poor turn-off stars selected from SDSS/SEGUE. Based on differential analysis adopting stellar parameters from Balmer line profiles, we obtain the following results: i) Statistically significant scatter is found in [X/Fe] (X=Na, Mg, Cr, Ti, Sr and Ba), among which [Na/Fe] shows an apparent bimodal distribution, ii) Li abundances are ~0.3 dex lower in [Fe/H]<−3.5 than the Spite plateau value without significant scatter.
Studies on older lesbian, gay, bisexual and transgender (LGBT) adults in residential care point to their discrimination, invisibility and the taboo on LGBT lifestyles, and call for development of ‘gay-friendly’ care. Yet, the literature is short on how to create inclusive residential care for older LGBT people. We aim to acquire in-depth understanding of experiences and needs of LGBT older people concerning their inclusion and participation in care settings to contribute to development of inclusive and responsive care that structurally enhances visibility, ‘voice’ and wellbeing of LGBT residents. Responsive, multi-stakeholder research using interviews, participant observations and focus groups was conducted within three elderly care homes in the Netherlands. Thematic, interpretative analysis was performed. LGBT respondents reported social exclusion and the need to feel safe and at home and be yourself. Exclusive activities for LGBT people foster personal and relational empowerment. However, heterogenous activities seem crucial in dealing with stereotypical imaging, heteronormativity and an equality-as-sameness discourse that influenced culture and daily practice in the homes and negatively affected the position of LGBT older adults. For development of gay-friendly elderly care exclusionary social norms need to be addressed. Dialogical sharing of narratives can help to empower LGBT older adults and stimulate understanding and shared responsibility between LGBT and heterosexual older people, as well as professionals.
The earliest phases of Galactical chemical evolution and nucleosynthesis can be investigated by studying the old metal-poor stars. It has been recognized that a large fraction of metal-poor stars possess significant over-abundances of carbon relative to iron. Here we present the results of a 23-star homogeneously analyzed sample of metal-poor candidates from the Hamburg/ESO survey. We have derived abundances for a large number of elements ranging from Li to Pb. The sample includes four ultra metal-poor stars ([Fe/H] < −4.0), six CEMP-no stars, five CEMP-s stars, two CEMP-r stars and two CEMP-r/s stars. This broad variety of the sample stars gives us an unique opportunity to explore different abundance patterns at low metallicity.
We present preliminary results for the estimation of barium [Ba/Fe], and strontium [Sr/Fe], abundances ratios using medium-resolution spectra (1–2 Å). We established a calibration between the abundance ratios and line indices for Ba and Sr, using multiple regression and artificial neural network techniques. A comparison between the two techniques (showing the advantage of the latter), as well as a discussion of future work, is presented.
Prevalence monitoring of avian influenza in wild bird populations is important to estimate risks for the occurrence of potentially zoonotic and economically disastrous outbreaks of highly pathogenic avian influenza virus (AIV) in poultry worldwide. A targeted, cost-effective monitoring method for AIV in wild birds was developed, which is based on monitoring results for AIV in Germany and information on the distribution and abundance of wild bird species in selected habitat types. Spatial data were combined with virological and outbreak data for the period of 1 January 2006 to 31 December 2010. Using Germany as an example, we identified 11 indicator species. By concentrating monitoring efforts on these species in spatially confined locations, we propose a targeted and more cost-effective risk-based AIV monitoring approach that can be adapted universally for the identification of wild bird indicator species worldwide with the perspective of reducing sample sizes (and costs) without impairing the validity of the results.
Background: Congestive heart failure (CHF) has been associated with impaired cognitive function, but it is unclear if these changes are specific to CHF and if they get worse with time. We designed this study to determine if adults with CHF show evidence of cognitive decline compared with adults with and without coronary artery disease (CAD).
Methods: A longitudinal study was carried out of 77 adults with CHF (ejection fraction, EF < 0.4), 73 adults with a clinical history of CAD and EF > 0.6, and 81 controls with no history of CAD. The Cambridge Cognitive Examination of the Elderly (CAMCOG) was the primary outcome measure. Secondary measures included the California Verbal Learning Test (CVLT), digit coding and copying, Hospital Anxiety and Depression Scale (HADS), and the short form health survey (SF36). Endpoints were collected at baseline and after 12 and 24 months.
Results: The adjusted CAMCOG scores of CHF participants declined 0.9 points over two years (p = 0.022) compared with controls without CAD. There were no differences between the groups on other cognitive measures. Participants with CHF and with CAD experienced similar changes in cognitive function over two years. Left ventricular EF and six-minute walk test results could not explain the observed associations.
Conclusions: The changes in cognitive function and mood associated with CHF over two years are subtle and not specific to CHF.
Operation Smile International (OSI) is a Non-Government Organization (NGO) with experience providing surgical care throughout the world. OSI has vast logistical capacity, skilled and credential providers, and international relationships. Disaster response had been considered by OSI in the past, but never initiated. However, the magnitude of the Haiti disaster, coupled with request from Haitian OS Partners led to the initial disaster response of the OSI organization.
Discussion and Observations
This presentation will: (1) Describe the considerations and rationale that led OSI to this intervention. (2) Discuss the process of developing a disaster response within a relatively short period of time. (3) The response itself, and (4) Present how the lessons learned will be adapted to future OSI capacity and planning.
Background: Despite high levels of participation in dementia education, general practitioners (GPs) and residential care facility (RCF) staff report perceived learning needs. Small group education, which is flexible, individualized, practical and case-based, is sought. We aimed to develop educational interventions for GPs and RCF staff tailored to meet their perceived educational needs.
Methods: We used a consultative process to develop education programs. A flexible program for RCF staff was developed in 30-minute blocks, which could be combined in sessions of different lengths. The RCF program aimed to facilitate sustainable change by engaging local “Dementia Champions”. For GPs, face-to-face and self-directed packages were developed. We collected participant feedback to evaluate the program.
Results: GPs and RCF staff were recruited as part of a larger intervention study. Sixteen of the 27 GPs who were offered the dementia education participated. Two of the 16 GPs participated in both learning packages. A total of 45 GP feedback responses were received from 16 GPs: 28 out of 45 GPs (62%) reported that the participants' learning needs were entirely met. Eighteen of 19 facilities offered the intervention participated and 326 RCF staff attended one or more of the 94 RCF education sessions. Feedback was collected from 93 sessions: 1013 out of 1067 RCF staff feedback responses (95%) reported that the session met the participants' learning needs. Qualitative feedback was also strongly positive.
Conclusion: Participants perceived the education programs as meeting their needs. Despite explicit attempts to provide flexible delivery options, overall participation rates remained low.
The aim of this study was to investigate the assumed positive association of pre-existent and pregnancy-induced hypertension with the offspring’s weight and length gain in the first 14 months of life. We studied 3994 pregnant women and their offspring in a prospective community-based cohort study, starting between 2003 and 2004 (Amsterdam Born Children and their Development, ABCD study). Questionnaires obtaining information about hypertension during pregnancy were completed, and this was complemented with additional information from the obstetric caregiver. Anthropometry of the offspring was followed during the first 14 months of life. Main outcome measures were presence or absence of growth acceleration in weight or length (normal: ΔSDS ⩽ 0.67 v. growth acceleration: ΔSDS > 0.67). The relation between hypertension during pregnancy and weight and length gain was addressed by logistic regression analyses. We found that pre-existent hypertension was related to growth acceleration in weight and length. After correction for birth weight and pregnancy duration, the effect remained significant for growth acceleration in weight (OR 1.89; 95% CI 1.21–2.97; P < 0.01). Pregnancy-induced hypertension showed similar results, although correction for birth weight and pregnancy duration rendered the associations non-significant. In conclusion, infants of women with pre-existent hypertension during pregnancy more frequently have growth acceleration in weight and length, and yet the mechanisms acting on postnatal growth appear to be different.
The growing awareness of the importance of the fossil record in the Milky Way for
constraining galaxy formation theory is reflected by the increasing number of new ground-
and space-based surveys designed to unravel the formation history of the Galaxy. Recently,
a new kinematic survey has been produced by means of spectro-photometric data from the
Sloan Digital Sky Survey (SDSS-DR7) and high-quality proper motions derived from
multiepoch positions from the Guide Star Catalogue II (GSC-II). In this framework, we
assembled a sample of ~ 30 000 FGK nearby metal-poor (sub)dwarfs for which
selection and distance estimates take advantage of accurate stellar atmospheric parameters
(effective temperature, surface gravity and metallicity) derived from SDSS spectra. Here,
as one of the most interesting applications of this catalogue, we consider the feasibility
of probing fossil signatures of the formation of the Milky Way by selecting and analysing
subsamples of stars as tracers of the seven-dimensional space distribution (full
phase-space coordinates plus chemical abundance) of the Galactic halo population within a
few kiloparsecs from the Sun. Preliminary results exhibit statistical evidence for
discrete overdensities localised in kinematics and in the space of adiabatic invariants
(angular momentum and energy). By examination of their intrinsic properties, we suggest
that they may be possible fossil signatures of past mergers or other accretion events.
We recently presented (Sbordone et al., 2009a) the largest sample to date of lithium abundances in extremely metal-poor (EMP) Halo dwarf and Turn-Off (TO) stars. One of the most crucial aspects in estimating Li abundances is the Teff determination, since the Li I 670.8 nm doublet is highly temperature sensitive. In this short contribution we concentrate on the Teff determination based on Hα wings fitting, and on its sensitivity to the chosen stellar gravity.
The abundance derivation of heavy r-elements may provide a better understanding of the r-process, and the determination of several reference r-elements should allow a better determination of the star's age. The spatial ultraviolet (UV) region presents a large number of lines of heavy elements, and in some cases such as Bi, Pt, Au, detectable lines are only available in the UV. The extreme “r-process star” CS 31082-001 ([Fe/H] = −2.9) was observed in the spatial UV in order to determine abundances of the heavy elements, using STIS on board HST.
The structure and kinematics of the recognized stellar components of the Milky Way are explored, based on well-determined atmospheric parameters and kinematic quantities for 32360 “calibration stars” from the Sloan Digital Sky Survey (SDSS) and its first extension, (SDSS-II), which included the sub-survey SEGUE: Sloan Extension for Galactic Understanding and Exploration. Full space motions for a sub-sample of 16920 stars, exploring a local volume within 4 kpc of the Sun, are used to derive velocity ellipsoids for the inner- and outer-halo components of the Galaxy, as well as for the canonical thick-disk and proposed metal-weak thick-disk populations. This new sample of calibration stars represents an increase of 60% relative to the numbers used in a previous analysis. A Maximum Likelihood analysis of a local sub-sample of 16920 calibration stars has been developed in order to extract kinematic information for the major Galactic components (thick disk, inner halo, and outer halo), as well as for the elusive metal-weak thick disk (MWTD). We measure velocity ellipsoids for the thick disk, the MWTD, the inner halo, and the outer halo, demonstrate that the MWTD may be a component that is kinematically and chemically independent of the canonical thick disk (and put limits on the metallicity range of the MWTD), and derive the inferred spatial density profiles of the inner/outer halo components. We also present evidence for tilts in the velocity ellipsoids for stars in our sample as a function of height above the plane, for several ranges in metallicity, and confirm the shift of the observed metallicity distribution function (MDF) from the inner-halo to the outer-halo dominated sample.
We present the largest sample available to date of lithium abundances in extremely metal poor (EMP) Halo dwarfs. Four Teff estimators are used, including IRFM and Hα wings fitting against 3D hydrodynamical synthetic profiles. Lithium abundances are computed by means of 1D and 3D-hydrodynamical NLTE computations. Below [Fe/H]~−3, a strong positive correlation of A(Li) with [Fe/H] appears, not influenced by the choice of the Teff estimator. A linear fit finds a slope of about 0.30 dex in A(Li) per dex in [Fe/H], significant to 2–3 σ, and consistent within 1 σ among all the Teff estimators. The scatter in A(Li) increases significantly below [Fe/H]~−3. Above, the plateau lies at 〈A(Li)3D, NLTE〉 = 2.199 ± 0.086. If the primordial A(Li) is the one derived from standard Big Bang Nucleosynthesis (BBN), it appears difficult to envision a single depletion phenomenon producing a thin, metallicity independent plateau above [Fe/H] = −2.8, and a highly scattered, metallicity dependent distribution below.
We report on medium-resolution near-IR spectroscopy of a sample of over 60 Carbon-Enhanced Metal-Poor (CEMP) stars observed with SOAR/OSIRIS, selected from the HK survey of Beers and colleagues and the Hamburg/ESO Survey of Christlieb and colleagues. Oxygen abundances from the molecular CO lines as well as rough estimates of 12C/13C ratios are estimated from the near-IR spectra of these stars. Near-IR model spectra with varying oxygen abundances, in combination with previously determined parameters from optical spectra are used for the estimation of abundances for this sample. As both oxygen abundances and 12C/13C ratios are tracers of nucleosynthesis, we hope to gain information about Galactic nucleosynthesis through the analysis of this sample.