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Important Bird and Biodiversity Areas (IBAs) are sites identified as being globally important for the conservation of bird populations on the basis of an internationally agreed set of criteria. We present the first review of the development and spread of the IBA concept since it was launched by BirdLife International (then ICBP) in 1979 and examine some of the characteristics of the resulting inventory. Over 13,000 global and regional IBAs have so far been identified and documented in terrestrial, freshwater and marine ecosystems in almost all of the world’s countries and territories, making this the largest global network of sites of significance for biodiversity. IBAs have been identified using standardised, data-driven criteria that have been developed and applied at global and regional levels. These criteria capture multiple dimensions of a site’s significance for avian biodiversity and relate to populations of globally threatened species (68.6% of the 10,746 IBAs that meet global criteria), restricted-range species (25.4%), biome-restricted species (27.5%) and congregatory species (50.3%); many global IBAs (52.7%) trigger two or more of these criteria. IBAs range in size from < 1 km2 to over 300,000 km2 and have an approximately log-normal size distribution (median = 125.0 km2, mean = 1,202.6 km2). They cover approximately 6.7% of the terrestrial, 1.6% of the marine and 3.1% of the total surface area of the Earth. The launch in 2016 of the KBA Global Standard, which aims to identify, document and conserve sites that contribute to the global persistence of wider biodiversity, and whose criteria for site identification build on those developed for IBAs, is a logical evolution of the IBA concept. The role of IBAs in conservation planning, policy and practice is reviewed elsewhere. Future technical priorities for the IBA initiative include completion of the global inventory, particularly in the marine environment, keeping the dataset up to date, and improving the systematic monitoring of these sites.
To date, Ireland has been a leading light in the provision of youth mental health services. However, cognisant of the efforts of governmental and non-governmental agencies working in youth mental health, there is much to be done. Barriers into care as well as discontinuity of care across the spectrum of services remain key challenges. This editorial provides guidance for the next stage of development in youth mental care and support that will require significant national engagement and resource investment.
We present a multi-frequency study of the intermediate spiral SAB(r)bc type galaxy NGC 6744, using available data from the Chandra X-Ray telescope, radio continuum data from the Australia Telescope Compact Array and Murchison Widefield Array, and Wide-field Infrared Survey Explorer infrared observations. We identify 117 X-ray sources and 280 radio sources. Of these, we find nine sources in common between the X-ray and radio catalogues, one of which is a faint central black hole with a bolometric radio luminosity similar to the Milky Way’s central black hole. We classify 5 objects as supernova remnant (SNR) candidates, 2 objects as likely SNRs, 17 as H ii regions, 1 source as an AGN; the remaining 255 radio sources are categorised as background objects and one X-ray source is classified as a foreground star. We find the star-formation rate (SFR) of NGC 6744 to be in the range 2.8–4.7 M⊙~yr − 1 signifying the galaxy is still actively forming stars. The specific SFR of NGC 6744 is greater than that of late-type spirals such as the Milky Way, but considerably less that that of a typical starburst galaxy.
Identifying the transmission sources and reservoirs of Streptococcus pneumoniae (SP) is a long-standing question for pneumococcal epidemiology, transmission dynamics, and vaccine policy. Here we use serotype to identify SP transmission and examine acquisitions (in the same household, local community, and county, or of unidentified origin) in a longitudinal cohort of children and adults from the Navajo Nation and the White Mountain Apache American Indian Tribes. We found that adults acquire SP relatively more in the household than other age groups, and children 2–8 years old typically acquire in their own or surrounding communities. Age-specific transmission probability matrices show that transmissions within household were mostly seen from older to younger siblings. Outside the household, children most often transmit to other children in the same age group, showing age-assortative mixing behavior. We find toddlers and older children to be most involved in SP transmission and acquisition, indicating their role as key drivers of SP epidemiology. Although infants have high carriage prevalence, they do not play a central role in transmission of SP compared with toddlers and older children. Our results are relevant to inform alternative pneumococcal conjugate vaccine dosing strategies and analytic efforts to inform optimization of vaccine programs, as well as assessing the transmission dynamics of pathogens transmitted by close contact in general.
A radiochemical 71Ga−71 Ge experiment to determine the integral flux of neutrinos from the sun has been constructed at the Baksan Neutrino Observatory in the USSR. Measurements have begun with 30 tonnes of gallium. The experiment is being expanded with the addition of another 30 tonnes. The motivation, experimental procedures, and present status of this experiment are presented.
The discrete source of radio emission in Sagittarius is among the most intense in the whole sky, but its situation in the belt of emission from ionized hydrogen and other sources associated with the galactic plane makes it difficult to observe. The observations described in this paper were made at frequencies of 38, 81·5, 210, and 500 Mc./s.; at these low frequencies it is particularly difficult to obtain sufficient aerial resolving power to distinguish the discrete source from the background. Interferometer aerials were therefore used, and at 38 and 210 Mc./s. spacings up to λ60 were used, sufficient to resolve the source completely. At 81·5 Mc./s. various sections of the large interferometer aerial were used.
We examine the roles of actuaries in UK life offices, along with trends, challenges to and opportunities for actuaries. We carry out an analysis of senior roles in life offices, a questionnaire survey and interviews with relevant senior personnel. We find that actuaries occupy many important roles in life offices and are regarded as having good industry knowledge and technical skills, especially in financial modelling. There are fewer executive directors and more non-executive directors of life offices who are actuaries compared with the position in 1990. A higher proportion of reserved roles is outsourced to consultants than was the case in 1990. Only a small number of Actuarial Function Holders are directors. Actuaries are more siloed than was the case in the past, although actuaries are well represented in the finance and risk functions of many offices. Although actuarial work in connection with the preparation for Solvency II will decline, there will be important ongoing requirements for actuaries following Solvency II implementation. We also see opportunities for actuaries in four areas: in risk management, in financial analysis and management based on Solvency II and international financial reporting standards, in connection with “big data”, and in product development and the customer proposition. There are implications for the examination syllabus, continuing professional development and research.
Methods that accurately estimate animal abundance or density are crucial for wildlife management. Although numerous techniques are available, there have been few comparisons of the precision and cost-effectiveness of different approaches. We assess the precision and cost of three methods for estimating densities of the Endangered Grevy's zebra Equus grevyi. We compare distance sampling and photographic capture–recapture, and a new technique, the random encounter model (REM) that uses camera-trap encounter rates to estimate density. All three methods provide comparable density estimates for Grevy's zebra and are preferable to the common practice of raw counts. Photographic capture–recapture is the most precise and line-transect distance sampling the least precise. Line transects and photographic capture–recapture surveys are cost-effective in the first year and REM is most cost-effective in the long-term. The methods used here for Grevy's zebra may be applied to other rangeland ungulates. We suggest that for single species monitoring programmes in which individuals can be identified, photographic capture–recapture surveys may be the preferred method for estimating wildlife abundances. When encounter rates are low, distance sampling lacks the precision of the other methods but its cost advantage may make it appropriate for long-term or multi-species monitoring programmes. The REM is an efficient and precise method of estimating densities but has high initial equipment costs. We believe REM has the potential to work well for many species but it requires independent estimates of animal movements and group size.
By building reconstruction models for a case of gastroenteritis in the general population moving through different steps of the surveillance pyramid we estimated that millions of illnesses occur annually in the European population, leading to thousands of hospitalizations. We used data on the healthcare system in seven European Union member states in relation to pathogen characteristics that influence healthcare seeking. Data on healthcare usage were obtained by harmonized cross-sectional surveys. The degree of under-diagnosis and underreporting varied by pathogen and country. Overall, underreporting and under-diagnosis were estimated to be lowest for Germany and Sweden, followed by Denmark, The Netherlands, UK, Italy and Poland. Across all countries, the incidence rate was highest for Campylobacter spp. and Salmonella spp. Incidence estimates resulting from the pyramid reconstruction approach are adjusted for biases due to different surveillance systems and are therefore a better basis for international comparisons than reported data.
This study explores the consequences of structure on the electronic properties of magnetic multilayers. Epitaxial layers of Co and Cu are grown on Cu(100) in a new deposition system that couples sputter-deposition with MBE and contains a wide range of characterization tools, including RHEED, LEED, and Kerr effect. This system can be coupled in situ to spin-polarized, angle-resolved photoemission and to resonant, magnetic X-ray scattering, both employing synchrotron radiation. The interface structure turns out to be critical in determining the coercivity and the presence of quantum well states, which determine oscillatory magnetic coupling.
Nanophosphors correspond to nanostructured inorganic insulator materials that emit light under particle or electromagnetic radiation excitation. In this work we investigate the structure and luminescent properties of Ce-doped Lu2SiO5 (LSO) nanophosphors prepared by solution combustion synthesis with the Ce content 0.1 to 12 at. %. Samples were characterized by transmission electron microscopy (TEM), line scan electron energy-loss spectroscopy (EELS), x-ray diffraction (XRD), and electron paramagnetic resonance (EPR) spectroscopy. Photoluminescence excitation and emission spectra are composed of two major bands centered at 360 and 430 nm, respectively. These results reveal a red-shift and enhanced Stokes shift for the nanophosphors when compared to bulk. Ce content was also found to affect photoluminescence emission intensity and fluorescent lifetime. The nanophosphor concentration quenching curve presents a broad maximum centered at 1 at.%. Lifetime measurements show a continuous decrease from 34 to 21 ns as Ce content is increased.
New copper rich alloys with elemental additions of transition metals and group IIIA and IVA elements have been prepared by casting and rapid solidification. The prepared alloys show very interesting microstructures; a thick surface layer with nanocrystalline eutectic like structure, while in the bulk the microstructure is coarser lamellar or dendritic. Their microhardness was found to be exceptionally high for Cu rich alloys, reaching values of 450-550HV. Furthermore, the microhardness of the surface layer is higher than that in the bulk, indicating that these alloys can be considered for a variety of applications including tribological and structural.
The effects of snowmobile traffic on the winter home-ranges, movements, and activity patterns, of White-tailed Deer (Odocoileus virginianus), were studied during two winters in northern Wisconsin. There were no significant differences in home-range size and habitat use of the Deer in areas with and without snowmobiling. However, snowmobiling caused some Deer to leave the immediate vicinity of the snowmobile trail. Deer were most affected when they were within 61 m of the snowmobile trail.
1. An epizootic killing 90% of a stock of 500 guinea-pigs has been described; cultures from these guinea-pigs frequently gave an organism indistinguishable by cultural or serological tests from the B. aertryck and the B. suipestifer.
2. This organism was highly pathogenic when inoculated subcutaneously into guinea-pigs and of low pathogenicity when given to them with food.
3. Healthy contacts put with animals infected subcutaneously or fed with the bacillus did not die.
4. Sterile filtrates of organs of guinea-pigs of the infected stock administered by different methods frequently killed.
5. The evidence definitely suggests that the essential infecting agent in the epizootic was a filter-passer.