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Habitat alteration and climate change are important threats to terrestrial biodiversity in the tropics. Endorsing flagship or umbrella species can help conserve sympatric biodiversity, restore degraded ecosystems and achieve United Nations Sustainable Development Goals (UN SDGs). The Ethiopian wolf (Canis simensis) is a rare and endemic Ethiopian canid. It is Africa’s most endangered canid species and is restricted to several isolated patches of Afroalpine habitats. While its behavioural ecology and conservation biology have been well studied, studies of the Ethiopian wolf’s significance for the conservation of its habitat and sympatric species are lacking. Here we use geographical range overlap and geospatial modelling to evaluate the importance of the Ethiopian wolf as a flagship and/or umbrella species. We assess whether conservation interventions targeting the Ethiopian wolf could help to restore and protect Afroalpine habitat and conserve sympatric species whilst simultaneously providing a wide range of socioeconomic and environmental benefits. We found that Ethiopian wolves share their range with 73 endemic and/or threatened vertebrate species, 68 of which are Afroalpine ecosystem species, and at least 121 endemic and/or threatened plant species. Ethiopian wolves are taxonomically distinctive and charismatic species classified as Endangered on the International Union for Conservation of Nature (IUCN) Red List. Thus, they meet both the flagship and umbrella species criteria to restore Afroalpine habitats and conserve threatened sympatric species. A conservation strategy protecting and restoring Afroalpine habitat has the potential to contribute to achieving at least five of the 17 UN SDGs. The protection of flagship and umbrella species should be integrated into broader regional biodiversity and habitat conservation.
Myrmecochory, the dispersal of seeds with lipid-rich appendages by ants, is a significant ant–plant interaction. Less well understood is the potential for ant dispersal of non-myrmecochorous seeds. Here we investigate ant–diaspore interactions in a West African montane habitat. We combine observation with depot experiments to determine ant species that move diaspores and distance moved across a forest-edge-grassland gradient. We recorded seed cleaning by ants using a bird/mammal dispersed Paullinia pinnata to determine whether seed cleaning improved plant fitness. We found that two out of a total of 17 ant species (Pheidole sp. 1 and Myrmicaria opaciventris) interacted with 10 species of non-myrmecochorous diaspores across nine plant families. Diaspores were from large canopy trees, understorey trees and vines. Both ant species interacted with small (≤0.24 g) and large (≥0.24 g) diaspores. Ants individually moved small diaspores up to 1.2 m and worked together to clean larger ones. Our experiments with P. pinnata showed that ants removed the pulp of 70% of fruit over 5 days. Cleaned seeds germinated significantly faster and produced seedlings with significantly longer shoot length and higher fresh weight than seedlings from intact seeds. Together our results suggest that ant dispersal may be less significant than seed cleaning in Afromontane forests. However, given the decline in vertebrate frugivores across Africa, a small dispersal advantage may become increasingly important to plant fitness.
In this paper, we describe the system design and capabilities of the Australian Square Kilometre Array Pathfinder (ASKAP) radio telescope at the conclusion of its construction project and commencement of science operations. ASKAP is one of the first radio telescopes to deploy phased array feed (PAF) technology on a large scale, giving it an instantaneous field of view that covers $31\,\textrm{deg}^{2}$ at $800\,\textrm{MHz}$. As a two-dimensional array of 36$\times$12 m antennas, with baselines ranging from 22 m to 6 km, ASKAP also has excellent snapshot imaging capability and 10 arcsec resolution. This, combined with 288 MHz of instantaneous bandwidth and a unique third axis of rotation on each antenna, gives ASKAP the capability to create high dynamic range images of large sky areas very quickly. It is an excellent telescope for surveys between 700 and $1800\,\textrm{MHz}$ and is expected to facilitate great advances in our understanding of galaxy formation, cosmology, and radio transients while opening new parameter space for discovery of the unknown.
To identify key school-level contexts and mechanisms associated with implementing a provincial school food and beverage policy.
Design:
Realist evaluation. Data collection included semi-structured interviews (n 23), structured questionnaires (n 62), participant observation at public events (n 3) and scans of school, school district and health authority websites (n 67). The realist heuristic, context + mechanism → outcome configuration was used to conduct the analysis.
Setting:
Public schools in five British Columbia (BC), Canada school districts.
Participants:
Provincial and regional health and education staff, private food vendors and school-level stakeholders.
Results:
We identified four mechanisms influencing the implementation of BC’s school food and beverage sales policy. First, the mandatory nature of the policy triggered some actors’ implementation efforts, influenced by their normative acceptance of the educational governance system. Second, some expected implementers had an opposite response to the mandate where they ignored or ‘skirted’ the policy, influenced by values and beliefs about the role of government and school food. A third mechanism related to economics demonstrated ways vendors’ responses to school demand for compliance with nutritional Guidelines were mediated by beliefs about food preferences of children, health and food. The last mechanism demonstrated how resource constraints and lack of capacity led otherwise motivated stakeholders to not implement the mandatory policy.
Conclusion:
Implementation of the food and beverage sales policy at the school level is shaped by interactions between administrators, staff, parent volunteers and vendors with contextual factors such as varied motivations, responsibilities and capacities.
A Miocene porphyry belonging to the sheshonite association contains 7 cm sanidine megacrysts in a groundmass of microphenocrysts of labradoritebytownite, augite, sporadic hastingsite, magnetite, sphene, K feldspar, apatite, Ca zeolite and calcite. The megacrysts (Or78–94) are enriched in BaO (≃ 2.0 wt%) and SrO relative to the groundmass. Although mineralogr and texture suggest that the megacrysts were suspended in a liquid, now represented by the groundmass, calculated liquid densities except for dry melts are less than those observed for the megacrysts and it is concluded that the original magma contained very little water. It possibly originated in a subduction zone with the main hycration taking place at shallow levels of intrusion during contact with groundwater. This produced zeolitization of the feldspars and may have played a part in the K enrichment at the margins of the sanidine megacrysts.
Jointed goatgrass is an exotic species introduced into the western United States from Eurasia. The weed is an agricultural pest infesting winter wheat fields and causing economic loss. Common ancestry between the two species enables interspecific hybridization, thus providing a mechanism for gene flow to occur. This can facilitate the accumulation of novel genes, which could increase the wild species' competitiveness with wheat and its ability to invade novel habitats. Interest in the development of transgenic wheat cultivars has increased the concern for interspecific gene flow. Gene introgression requires recurrent backcrossing to the weedy species after the initial hybridization event. Field experiments were conducted at two locations in Colorado in 2007–2008 and 2008–2009, with jointed goatgrass acting as the sole source of viable pollen for fertilization of transplanted hybrid plants. Backcrossing rates were determined by conducting germination studies on spikes collected from a total of 206 hybrid plants. Pollination by jointed goatgrass led to the production of 463 BC1 plants from seed produced on these 206 hybrid plants. Ninety-five percent confidence intervals estimate the rate of backcrossing at 0.028 to 0.306% and 0.077 to 0.604%, with medians of 0.062 and 0.152%, respectively, at the two locations. The results demonstrate that backcrossing to jointed goatgrass can occur, despite low rates of hybrid fertility. Subsequent backcrossing would make it likely that a wheat gene conferring a selective advantage will introgress into the weedy population. For the U.S. Great Plains, it is possible that transgenic wheat cultivars will be released in the future and determining proper management of these cultivars is necessary to minimize hybridization and advantageous gene introgression into weedy relatives.
The Parkes pulsar data archive currently provides access to 144044 data files obtained from observations carried out at the Parkes observatory since the year 1991. Around 105 files are from surveys of the sky, the remainder are observations of 775 individual pulsars and their corresponding calibration signals. Survey observations are included from the Parkes 70 cm and the Swinburne Intermediate Latitude surveys. Individual pulsar observations are included from young pulsar timing projects, the Parkes Pulsar Timing Array and from the PULSE@Parkes outreach program. The data files and access methods are compatible with Virtual Observatory protocols. This paper describes the data currently stored in the archive and presents ways in which these data can be searched and downloaded.
Theory predicts that not all plant species will be equally affected by disruption to their pollinator mutualisms because traits such as breeding system and mutualism strength can affect their response. We investigated these traits in three species of Afromontane mistletoe Globimetula braunii, Agelanthus brunneus and A. djurensis in Ngel Nyaki Forest Reserve, Nigeria, to test whether the traits were reliable indicators of relative reproductive success and could be used to predict relative vulnerability to pollinator loss. For each mistletoe species, insect and bird visitors were identified during a 160–240-min observation period of 4–10 plants and their roles in flower opening and fruit set were investigated using exclusion experiments applied to 250–500 flowers. We found that all three mistletoes are self-compatible but not capable of autonomous self-fertilization. The pollinator assemblage comprised four species of sunbird (Cyanomitris spp., Cinnyris spp.) and a small social wasp (Vespinae). None of the mistletoes requires birds for flower opening: G. braunii flowers self-opened in the absence of pollinators, whereas insects opened both Agelanthus spp. Irrespective of flower opening, each mistletoe species requires sunbirds for effective pollination and fruit set. Only G. braunii demonstrated pollen limitation (pollen limitation index = 0.504) which may be an early indication of mutualism breakdown. We suggest that mistletoes be considered as indicators of habitat condition and functioning within Afromontane forest ecosystems.
We report a study of the relation between dust and gas over a 100 deg2 area inthe Taurus molecular cloud. We compare the H2 column density derived from dustextinction with the CO column density derived from the 12CO and 13COJ = 1 → 0 lines. We derive the visual extinction from reddeningdetermined from 2MASS data. The comparison is done at an angular size of 200′′,corresponding to 0.14 pc at a distance of 140 pc. We find that the relation between visualextinction AV and N(CO) is linear betweenAV ≃ 3 and 10 mag in the region associated with theB213–L1495 filament. In other regions the linear relation flattens forAV ≳ 4 mag. Accounting for the observed relation between thecolumn density of CO and CO2 ices and AV, we find alinear relationship between the column of carbon monoxide and dust for observed visualextinctions up to the maximum value in our data ≃23 mag.
This paper examines two related problems from liquid-film theory. Firstly, a steady-state flow of a liquid film down a pre-wetted plate is considered, in which there is a precursor film in front of the main film. Assuming the former to be thin, a full asymptotic description of the problem is developed and simple analytical estimates for the extent and depth of the precursor film's influence on the main film are provided. Secondly, the so-called drag-out problem is considered, where an inclined plate is withdrawn from a pool of liquid. Using a combination of numerical and asymptotic means, the parameter range where the classical Landau–Levich–Wilson solution is not unique is determined.
In August 1988 an increase was noted in the number of cases of cryptosporidiosis identified by the microbiology laboratory at Doncaster Royal Infirmary. By 31 October, 67 cases had been reported. Preliminary investigations implicated the use of one of two swimming pools at a local sports centre and oocysts were identified in the pool water. Inspection of the pool revealed significant plumbing defects which had allowed ingress of sewage from the main sewer into the circulating pool water. Epidemiological investigation confirmed an association between head immersion and illness. The pools were closed when oocysts were identified in the water and extensive cleaning and repair work was undertaken. The pool water was retested for cryptosporidial oocysts and found to be negative before the pool re-opened.
Previous methods of survey by American workers are described and the differences between the species of seaweed involved are emphasized. The small stature of the European kelps renders all methods of survey difficult and the results can only be described as the best approximations. The British survey was divided into (1) a preliminary survey in order to determine the regions with the biggest beds, and (2) a detailed survey, when some of these major beds were mapped in detail. The primary survey was a rapid affair and the results were based on information obtained from (a) use of boat and grapnel, (b) existence of cast weed, (c) lobster fishermen, (d) coastguards, fishery officers, borough surveyors, harbour-masters, (e) inspection from cliffs, (f) a study of Admiralty Charts.
In the section on the detailed survey the different types of grapnel employed and also the method of using the box sextant are described. The use of an echo-sounder to locate weed beds is discussed and the different types of record obtained over various types of bottom or weed are noted. The use of a viewbox and personal observation is also mentioned, and finally an account is given of aerial photography as a means of survey. The most suitable conditions for success are noted and also the technique of interpretation for both oblique and vertical photographs. The plotting of these two types of photograph is described in some detail.
A low activity mutant of glucose-6-phosphate dehydrogenase, G6pda-m1Neu has been used to position G6pd in the mouse X chromosome. Linkage tests with tabby, Ta and harlequin, Hq, indicate a likely gene order of Hq–G6pd–Ta. Muscular dystrophy, mdx, has been located by two-and three-point crosses using Hprt, Pgk-1 and Moblo and suggest a gene order of Hprt–mdx–Pgk-1–Moblo. Together with existing linkage data a tentative order for the seven loci is Hq–Hprt–G6pd–mdx–Ta–Pgk-1–Moblo. The relative positions of G6pd and mdx have not been directly tested and G6pd is assigned provisionally proximal to mdx. In the three point test using Hq, G6pd and Ta the recombination frequency found between Hq and Ta was 9·9 ± 2·6%, substantially less than the value of 20·5 ± 2·1% reported by Isaacson et al. (1974).
Leishmania turanica n.sp., found infecting the desert rodent Rhombomys opimus in the southern territories of the USSR and the Mongolian People's Republic, is described. This parasite exists sympatrically with L. major and L. gerbilli in R. opimus and is the predominant species. A total of 284 isolates of L. turanica from R. opimus, 3 from naturally infected Phlebotomus andrejevi and 1 from P. papatasi were characterized and found to be clearly distinguishable on isoenzyme and nuclear DNA characteristics from all other Old World taxa of Leishmania.
An experiment to measure the variation in the phenological and apical development ofwinter wheat (cv. Avalon) in England and Scotland is described. Ten sites which ranged from Aberdeen (57·2° N), the most northerly, to Newton Abbot (50·6° N), the most southerly, were included in the survey, and at each site seed was hand-sown in mid-September, October and November 1983. Developmental stages and sampling procedures were precisely defined to ensure uniformity in scoring by the observers at each site. Temperatures during the growing season were in line with the long-term means, though spring was cooler at all sites and summer warmer at most. The range of monthly-mean temperatures between sites was about the same as the difference between consecutive months. The method of analysis of development rates and durations was in terms of thermal time, modified by sensitivity to photoperiod and a vernalization requirement that slowed early development until a number of days of low temperatures had been experienced. In general, crops at northern sites developed more slowly than those in the south and particularly the south-west of England. There was less variation in the timing of apical stages for later sowings. Developmental rates responded linearly to temperature and photoperiod, with the base temperature increasing for later phases of development. The effect of photoperiod in modifying the rate of development was apparent for all developmental phases from emergence to anthesis, longer days accelerating development, but there was no effect on the duration of the grain-filling period. Vernalization exerted its effect solely within the phase from emergence to double ridge, and had a major influence on the variation between sites only for the first sowing.
The initiation of leaf and spikelet primordia was studied at sites ranging in latitude from Newton Abbot (50·6°N) to Aberdeen (57·2°N) in crops sown in the middle of September, October and November 1983. The rate of primordium initiation tended to decrease from south to north but there were also marked differences between quite close sites.
The rate of leaf initiation increased with temperature but photoperiod had little effect; the rate of spikelet initiation was affected both by temperature and by photoperiod. There were differences in the total number of leaves initiated which were only partlyexplained by differences in vernalization.
Expressing leaf and spikelet initiation rates in terms of thermal and photo-thermal time respectively showed a constant rate of leaf initiation and a constant and more rapid rate of spikelet initiation.
Photodynamic therapy is an innovative modality in the treatment of malignant and non-malignant diseases. Owing to its widespread use, there will be an increase in the number of photosensitized patients presenting for both elective and emergency anaesthesia. As one of the few centres involved in providing this specialized treatment for maxillofacial conditions, we would like to highlight its main anaesthetic considerations.
The English HCV lookback programme has identified some individuals with transfusion-transmitted HCV infection. The path from the collection of donations from HCV-infected donors to the identification of infected recipients was constructed. The probability of different outcomes at each branch was derived from data collected during this programme. This path of probabilities was then used to produce a complete estimate of the number of recipients infected by blood transfusions (dead and alive at the end of 1995) by re-entry of blood components that fell out of the lookback at various steps prior to recipient testing, and entry of components from HCV-infected donations that were never identified for lookback. Less than 14 000 recipients were estimated to have been infected with HCV during the decade prior to the start of donation testing. Over 60% of these were expected to have died by the end of 1995. Transfusion has infected a large group of individuals. However, this group constitutes a very small, and declining, proportion of all HCV infections in the population.
The variation of road surface temperature across a road network is influenced regionally by meteorological parameters and locally by geographical parameters. A fast and reliable technique is described which allows the continuous collection of high resolution, geographical data including the sky-view factor which is suitable for use in road climate modelling studies. Then, by use of regression analysis, the relative importance of five geographical parameters (altitude, topography, sky-view factor, landuse and road construction) is assessed with respect to road surface temperature and atmospheric stability. Results show that sky-view factors dominate surface temperatures at high atmospheric stability whereas altitude becomes increasingly important as stability decreases. Finally, a statistical road surface temperature model is discussed with the ability to explain up to 75% of the variation of residual road surface temperatures in the study area entirely by the interaction of geographical parameters.