219 research outputs found

    Applying a SNP-based tool for conservation of wild and managed black bees in Ireland

    Get PDF
    Apis mellifera mellifera (Amm) is threatened over much of its natural range. However, in Ireland microsatellite and mitochondrial data have shown that a significant population of this subspecies exists in pure form and is spread over a large geographical region on the Island. Black bees have been managed and protected by beekeepers on the island, some of whom formed the Native Irish Honeybee Society (NIHBS)in 2012 and a breeding programme was initiated for Amm in 2014/2015. The application of a SNP panel that detects hybridization between M and C lineages clearly supports other data showing that the majority of beekeepers included in the breeding programme indeed have bees with very low to no introgression from the C lineage. Furthermore, SNP data has also been applied to the first feral bee colonies located in Ireland subsequent to the introduction of Varroa. Here we will present on the use of molecular data as an aid to manage and conserve honeybees in Ireland, and to elucidate patterns in colour variation and honeybee subspecies purity in wild and managed bees with a view towards improving conservation approaches in the face of a potential hybridization threat.info:eu-repo/semantics/publishedVersio

    Effectiveness of exercise programs to reduce falls in older people with dementia living in the community: A systematic review and meta-analysis

    Get PDF
    Objective: The objective of this systematic review and meta-analysis is to evaluate the effectiveness of exercise programs to reduce falls in older people with dementia who are living in the community. Method: Peer-reviewed articles (randomized controlled trials [RCTs] and quasi-experimental trials) published in English between January 2000 and February 2014, retrieved from six electronic databases – Medline (ProQuest), CINAHL, PubMed, PsycInfo, EMBASE and Scopus – according to predefined inclusion criteria were included. Where possible, results were pooled and meta-analysis was conducted. Results: Four articles (three RCT and one single-group pre- and post-test pilot study) were included. The study quality of the three RCTs was high; however, measurement outcomes, interventions, and follow-up time periods differed across studies. On completion of the intervention period, the mean number of falls was lower in the exercise group compared to the control group (mean difference [MD] [95% confidence interval {CI}] =-1.06 [-1.67 to -0.46] falls). Importantly, the exercise intervention reduced the risk of being a faller by 32% (risk ratio [95% CI] =0.68 [0.55–0.85]). Only two other outcomes were reported in two or more of the studies (step test and physiological profile assessment). No between-group differences were observed in the results of the step test (number of steps) (MD [95% CI] =0.51 [-1.77 to 2.78]) or the physiological profile assessment (MD [95% CI] =-0.10 [-0.62 to 0.42]).Conclusion: Findings from this review suggest that an exercise program may potentially assist in preventing falls of older people with dementia living in the community. However, further research is needed with studies using larger sample sizes, standardized measurement outcomes, and longer follow-up periods, to inform evidence-based recommendations

    Can introgression in M-lineage honey bees be detected by abdominal colour patterns?

    Get PDF
    Honey bee abdominal pigmentation is one of the most recognisable traits and it is often used by beekeepers as an indicator of M-lineage subspecies purity. However, this approach may negatively impact population diversity and is futile if there is no association between tergite colour patterns and the genetic background. To assess whether this trait can be used as a proxy for introgression proportions in M-lineage subspecies, we genotyped, with highly informative SNP assays, A. m. mellifera and A. m. iberiensis individuals displaying four different colour phenotypes. The SNP data detected highly introgressed bees exhibiting a black phenotype and, at the same time, pure or marginally introgressed bees with yellow banding patterns, in both subspecies. Despite these observations, contrary to A. m. iberiensis , in A. m. mellifera , introgression proportions revealed to be a significant predictor of abdominal pigmentation. Therefore, abdominal pigmentation could be used by A. m. mellifera conservationists to guide colony selection when genetic tools are unavailable.KAB was funded by Dr. Tony Ryan research scholarship and an Irish Research Council scholarship. This work was financed by the Native Irish Honeybee Society (NIHBS), Federation of Irish Beekeeping Associations (FIBKA) and FEDER (Fundo Europeu de Desenvolvimento Regional) through the program COMPETE 2020–POCI (Programa Operacional para a Competividade e Internacionalização) and by the Portuguese funds through FCT (Fundação para a Ciência e a Tecnologia) in the framework of the project BeeHappy (POCI-01-0145-FEDER-029871).info:eu-repo/semantics/publishedVersio

    Conservation of European M-lineage honey bees using abdominal colour as an indicator of subspecies purity has pitfalls

    Get PDF
    There are 31 honey bee (Apis mellifera) recognized subspecies, which have been grouped into four main lineages. Two of these lineages occur naturally in Europe: M in western and northern Europe and C in southeastern Europe. In Europe, M-lineage groups only two subspecies, Apis mellifera mellifera and Apis mellifera iberiensis, both being black in colour. C-Lineage groups have instead eight subspecies, including one of the beekeepers-favored and phenotypically distinct, the yellow Apis mellifera ligustica from Italy. M-lineage honey bees’ distribution has been changing and in some countries, the native bee is being replaced or hybridised with C-lineage subspecies. Honey bee abdominal pigmentation is one of the most recognisable traits and it has been used by beekeepers as an indicator of subspecies identity. However, this approach may negatively impact population diversity and is futile if there is no association between tergite colour patterns and genetic background. To test this approach, we calculated the introgression level of A. m. mellifera (N=162) and A. m. iberiensis individuals (N=559) with different colour phenotypes and from a wide geographical range using informative SNPs. In this study, many A. m. mellifera samples showed high levels of C-lineage introgression. The individuals collected in Iberia were revealed to be pure. Introgressed A. m. iberiensis individuals were all from the Azores, where a high frequency of C-lineage mitotypes exists in several islands. Our results showed that for both subspecies, it is not possible to directly identify introgressed individuals from observed colour patterns, as we found black honey bees with a considerable amount of introgression and honey bees with yellow banding that were pure or marginally introgressed. With this study, we hope to increase awareness among stakeholders of the need to use other tools to select honey bees for conservation and breeding purposes.This work was financed by the Native Irish Honeybee Society (NIHBS), Federation of Irish Beekeeping Associations (FIBKA) and FEDER (Fundo Europeu de Desenvolvimento Regional) through the program COMPETE 2020–POCI (Programa Operacional para a Competividade e Internacionalização) and by the Portuguese funds through FCT (Fundação para a Ciência e a Tecnologia) in the framework of the project BeeHappy (POCI-01-0145-FEDER-029871). FCT provided financial support by national funds (FCT/MCTES) to CIMO (UIDB/00690/2020). Dora Henriques is funded by BeeHappy and MEDIBEES which is part of the PRIMA programme supported by the European Union.info:eu-repo/semantics/publishedVersio

    The \u3cem\u3eHubble Space Telescope\u3c/em\u3e Sample of Radio-loud Quasars: Ultraviolet Spectra of the First 31 Quasars

    Get PDF
    We report the first results from a continuing program to investigate the multifrequency spectrophotometric and other properties of a sample of about 50 radio-loud quasars in the redshift range ˜0.3-1.3. Here we present spectrophotometric data of high signal-to-noise ratio (≳20 in the continuum) of the first 31 radio-loud quasars, over the wavelength range from below Lyα to an observed wavelength of 3250 or 4800 Å, obtained using the Faint Object Spectrograph on the Hubble Space Telescope. We have also made quasi-simultaneous observations to extend these spectra beyond the Balmer lines -- either Hβ or Hα -- and those data will be presented in companion papers. In the ultraviolet and optical, the resolution is 300-400 km s-1 and in the infrared, about 1000 km s-1. The sample was selected by luminosity of the extended radio emission, and to cover a range of radio core-dominance, in order to test ideas relating to orientation of the continuum and emission- line regions to the observer\u27s line of sight. We present the ultraviolet spectra, and tabulate basic spectroscopic measurements: continuum flux densities and spectral indices, intensities and equivalent widths for all strong emission lines after deblending, as well as profile parameters such as various line widths and asymmetries. The relations between these and other parameters will be presented in detail in a later paper. In our low-redshift sample we have good coverage from C III λ977 to O VI λ1035, a region that is very confused by Lyman forest absorption in high-redshift quasars observed from the ground. We find that Lyβ is less than 10% of the strength of O VI λ1035. The ratio O VI λ1035/Lyα ˜0.21 supports photoionization models with high ionization and a small, dense broad-line region, although the weakness of C III λ977 typically 5% of Lyα-limits the amount of gas with densities ≳ 1010-1011 cm-3. The N III λ991 line is present at about 4% the strength of Lyα. In contrast to the lobe-dominant quasars, which have flat ultraviolet-optical continua (in Fv) all quasars with steep continua are radio core-dominant, and their broad lines tend to have lower equivalent width. Associated absorption is more prominent in the lobe-dominant quasars. Both these results are consistent with unified schemes in which a synchrotron-emitting jet is viewed at small angles to the line-of-sight in core-dominant quasars, and the line-of-sight at larger angles passes through cooler gas. In addition, we find and discuss significant differences in C IV λ1549 line asymmetries: the profiles of core-dominant quasars have stronger red wings, profiles of lobe-dominant quasars tend to be symmetric with both red and blue wings, and radio-quiet QSO profiles have stronger blue wings

    Towards precision radial velocity science with SALT’s High-Resolution Spectrograph

    Get PDF
    We describe efforts to equip the Southern African Large Telescope (SALT) for precision radial velocity (PRV) work. Our current focus is on commissioning the high-stability (HS) mode of the High-Resolution Spectrograph (HRS), the mode intended to support exoplanet science. After replacing the original commercial iodine cell with a custom-built, precisely characterised one and following established best practice in terms of observing strategy and data reduction, this system now delivers 3-4 m/s radial velocity stability on 5th and 6th magnitude stars. Unfortunately, the throughput is compromised by the HRS dichroic split being at 555 nm (i.e. roughly midway through the 100 nm span of the iodine absorption spectrum). Furthermore, SALT’s fixed elevation axis limits the exposure time available for a given target and hence the depth and/or precision achievable with the iodine cell. The HS mode’s simultaneous ThAr option uses the full 370–890 nm passband of the HRS and does not suffer gas cell absorption losses, so it may be more suitable for exoplanet work. The first step was to quantify the internal stability of the spectrograph, which requires simultaneously injecting arc light into the object and calibration fibres. The HS mode’s optical feed was modified accordingly, stability test runs were conducted and the necessary analysis tools were developed. The initial stability test yielded encouraging results and though more testing is still to be done, SAL a laser frequency comb to support the development of HRS PRV capability
    • …
    corecore