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The short spined crown-of-thorns starfish Acanthaster brevispinus inhabits deeper water soft bottom habitats, in contrast to the more infamous Indo-Pacific Acanthaster species complex of which population outbreaks have been responsible for widespread coral mortality throughout the Indo-West Pacific region. Acanthaster brevispinus has not previously been regarded as a threat to corals or coral reefs. Here, we report A. brevispinus occurring on mesophotic off-reef or inter-reef habitats in 20–70-m depths dominated by solitary corals off both the western and eastern coasts of Australia. On Ningaloo Reef, A. brevispinus were found on mushroom coral (Cycloseris distorta) beds using an underwater towed camera and further exploration using a remotely operated vehicle (ROV) confirmed predation by A. brevispinus on C. distorta. On the southern Great Barrier Reef, A. brevispinus in large numbers were found in habitat dominated by the dendrophylliid Heteropsammia cf. cochlea. Predation on H. cf. cochlea was also directly observed. This is the first confirmed report of predation on hard corals by A. brevispinus, and while there are yet to be any records of population outbreaks of this species, such outbreaks could have a significant effect on mesophotic solitary coral assemblages. [ABSTRACT FROM AUTHOR]

Previous work based on conjectural responses of minors predicted that the 2003 Texas requirement for parental consent for state-funded birth control to minors would lead to a large increase in underage pregnancies. We use state- and county-level data to test this prediction. The latter allow us to compare the impact of parental consent in counties with and without state-funded family planning clinics. We control for characteristics systematically correlated with the presence of state-funded clinics by combining difference-in-difference estimation with propensity score–weighted regressions. The evidence suggests that the parental consent mandate led to a large decrease in attendance at family planning clinics among teens but did not lead to an increase in underage pregnancies. [ABSTRACT FROM AUTHOR]

Strategies to control transboundary diseases have in the past generated unintended negative consequences for both the environment and local human populations. Integrating perspectives from across disciplines, including livestock, veterinary and conservation sectors, is necessary for identifying disease control strategies that optimise environmental goods and services at the wildlife-livestock interface. Prompted by the recent development of a global strategy for the control and elimination of foot-and-mouth disease (FMD), this paper seeks insight into the consequences of, and rational options for potential FMD control measures in relation to environmental, conservation and human poverty considerations in Africa. We suggest a more environmentally nuanced process of FMD control that safe-guards the integrity of wild populations and the ecosystem dynamics on which human livelihoods depend while simultaneously improving socio-economic conditions of rural people. In particular, we outline five major issues that need to be considered: 1) improved understanding of the different FMD viral strains and how they circulate between domestic and wildlife populations; 2) an appreciation for the economic value of wildlife for many African countries whose presence might preclude the country from ever achieving an FMD-free status; 3) exploring ways in which livestock production can be improved without compromising wildlife such as implementing commodity-based trading schemes; 4) introducing a participatory approach involving local farmers and the national veterinary services in the control of FMD; and 5) finally the possibility that transfrontier conservation might offer new hope of integrating decision-making at the wildlife-livestock interface. [ABSTRACT FROM AUTHOR]

The concern about the effects of the noise of human activities on marine mammals, particularly whales, has led to a substantial amount of research but there is still much that is not understood, particularly in terms of the behavioural responses to noise and the longer term biological consequences of these responses. There are many challenges in conducting experiments that adequately assess behavioural reactions of whales to noise. These include the need to obtain an adequate sample size with the necessary controls and to measure the range of variables likely to affect the observed response. Analysis is also complex. Well designed experiments are complex and logistically difficult, and thus expensive. This paper discusses the challenges involved and how these are being met in a major series of experiments in Australian waters on the response of humpback whales to the noise of seismic airgun arrays. The project is known as BRAHSS (Behavioural Response of Australian Humpback whales to Seismic Surveys) and aims to provide the information that will allow seismic surveys to be conducted efficiently with minimal impact on whales. It also includes a study of the response to ramp-up in sound level which is widely used at the start of operations, but for which there is little information to show that it is effective. BRAHSS also aims to infer the longer term biological significance of the responses from the results and the knowledge of normal behaviour. The results are expected to have relevance to other sources and species. [ABSTRACT FROM AUTHOR]

In this paper we demonstrate how standard techniques for measuring productivity growth can be applied to the broadcasting sector to provide a benchmark for reasonable efficiency savings which public finance officials might expect public service broadcasting (PSB) to achieve. Using establishment level data from the UK, we produce estimates of productivity growth amongst commercial broadcasters between 1999 and 2003, which provide some evidence that improvements to PSB can reasonably be expected to be funded by efficiency savings rather than solely by increases in public funding. [ABSTRACT FROM AUTHOR]

In this paper we demonstrate that the measurement of stock market efficiency is an important activity in establishing whether eastern European countries satisfy the Copenhagen Criteria for EU membership. Specifically, we argue that developing an efficient stock market should be an important policy focus for countries with aspirations to join the EU as it helps to demonstrate the existence of a functioning market economy. We illustrate this issue by examining the evolution of stock market efficiency in the Bucharest Stock Exchange from mid-1997 to September 2002. We use a GARCH model on daily price data and model the disturbances using the Student- t distribution to allow for ‘fat-tails’. We find strong evidence of inefficiency in the Bucharest Stock Exchange in that the lagged stock price index is a significant predictor of the current price index. This result is robust to the inclusion of variables controlling for calendar effects of the sort that have been observed in more developed stock markets. The level of inefficiency appears to diminish over time and we find evidence consistent with stock market efficiency in Romania after January 2000. [ABSTRACT FROM AUTHOR]

Argues that the pricing strategies companies in the British betting industry are likely to be an important source of monopoly rents, particularly in the market rents. Structure of the betting industry in Great Britain; Price setting behavior for various bets; Formal tests for the presence of monopoly power and results based on Great Britain betting data.

The genetic diversity of classical swine fever virus (CSFV) was studied by RT-PCR amplification and sequencing of a 409 bp fragment of the NS5B polymerase region. A total of 106 viruses isolated from 20 countries over a period of 52 years (1945–1997) were included in the phylogenetic study. The results showed that the viruses could be divided into two main groups. Group 1 consisted of Asian and South American isolates from the 1980s, as well as of old European and American isolates. Group 2 consisted mostly of recent European viruses from the 1980s and 1990s, and was further divided into three subgroups largely according to geographic origin and/or year of isolation. Five 1997 CSFV isolates from Germany, Netherlands and Italy clustered together indicating a common origin for these outbreaks, but two other 1997 isolations in different regions of Germany are likely due to different epidemiological events. The results show that the NS5B region of the genome gives a good resolution for phylogenetic studies of CSFV. Molecular epidemiology based on nucleotide sequence diversity is a useful tool for tracing virus spread and for developing disease control strategies. [ABSTRACT FROM AUTHOR]

Specific PCR primers were selected for each pestivirus genotype which flanked the 3′-part of the NS5B gene and more than three quarters of the 3′-UTR. PCR products were sequenced in both directions using an automatic sequencing device and analyzed by computer package program DNASTAR. A comparative analysis of the 3′ untranslated region (3′-UTR) of 82 viruses, representing the four genotypes of the Pestivirus genus, provided a similar phylogenetic grouping as other genomic regions. Intertypic recombination was not observed, but Border disease virus (BDV) and Bovine viral diarrhoea virus type 1 (BVDV I) showed great intragenotypic variability. In most pestiviruses the stop codon is TGA, but BDV isolates were found to have either a TAG or a TAA stop codon. Various deletions and insertions were observed in the 3′-UTR region. Viruses of the BVDV Ib group contained a characteristic deletion of 41 nucleotides. Compared to the 5′-UTR, the 3′-UTR was less conserved. The first 50–60 nucleotides were particularly variable, whilst the most conserved part was found at the 3′ end of the studied region. All 82 viruses contained AT-rich stretches, the positions and sizes of which differed between the genotypes. [ABSTRACT FROM AUTHOR]

The ability of a series of N-modified N-alkyl-5′-uronamides to cause presynaptic inhibition of transmitter release was examined in isolated guinea-pig ileum stimulated at 0.2 Hz. These analogs inhibited the twitch responses to nerve stimulation, the majority being full agonists with their inhibitory effects being antagonised by theophylline. These analogs had no significant effects on responses of ileum to carbachol. N-ethyl 5′-uronamide substitution resulted in an up to four-fold reduction in activity of N-substituted adenosine analogs, while stereoselectivity of the N-substituted analogs continued to be present. 5′-Uronamide substitutions to N-(3-pentyl)-adenosine resulted in a marked loss of activity when there were large alkyl groups at the amide or with amides of secondary amines. It was concluded that adenosine analogs interact with both the N6 and C-5′ regions of the adenosine receptor in this tissue, with the interaction being less than additive. [ABSTRACT FROM AUTHOR]

This study explored the nature of the purine domain N regions of the presynaptic adenosine receptors of guinea-pig ileum and of rat vas deferens. The experimental design tested a model of these receptors which is complementary to the structure of the N substituent of the classical A adenosine receptor agonist N-1-phenyl-2R-propyladenosine, ( R-PIA). Assays of activity employed ileal segments or the midportions of vasa deferentia under continuous electrical stimulation at 0.2 Hz. Structure activity correlations compared the EC-50s for twitch inhibition. As shown previously, R-PIA was 60-80 times more potent than its S diastereomer, the resultant of the positive contribution of propyl C-3 to activity as well as the negative influence of steric hindrance exerted by propyl C-3 of the S diastereomer. Other pairs of diastereomers having a chiral center adjacent to N showed that the stereoselectivity of the PIAs was generalizable. Biological activity appears to reside wholly in the N alkyl moiety; the phenyl or aryl groups of similar size actually diminished potency. The receptor subregions interacting with propyl C-1 and C-3 of R-PIA are each large enough to accomodate two - but not three - methylene residues, each methylene contributing additively to activity. Hydrophobicity is a prominent attribute of the propyl C-1 and C-3 subregions. The potencies of these analogs as inhibitors of presynaptic transmission in ileum or vas deferens are covariant with inhibition of [H]N-cyclohexyl-adenosine binding to rat cerebral cortical membranes. Singular exceptions to this generalization may represent organ- or species-dependent differences in receptor fine structure. [ABSTRACT FROM AUTHOR]

In the isolated rat vas deferens stimulated at 0.2 Hz, a series of 2′, 3′-, and 5′-substituted adenine nucleotides all inhibited the twitch responses, their actions being potentiated by the nucleoside transport inhibitors, HNBTGR, NBMPR and dipyridamole. The metabolism of these nucleotides was examined utilising HPLC analysis of the bathing medium after exposure to 30 μM nucleoside or nucleotide for 5 min. 5′-AMP, 5′-ADP, 5′-ATP, and NAD were all partially hydrolysed to adenosine, the relative extent of this being 5′-AMP>5′-ADP=5′-ATP≫NAD. However, the other nucleotides examined were not detectably converted to adenosine or to adenosine deamination products. These results indicate that the 2′-, 3′- and 5′-substituted nucleotides studied act at a P-purinoceptor in rat vas deferens to inhibit neurotransmission and, with the exception of 5′-AMP, 5′-ADP, 5′-ATP and NAD, all appear to act directly at this receptor. However, the 5′-adenine nucleotides (AMP, ADP and ATP) and NAD all appear to act at least partially indirectly subsequent to their hydrolysis to adenosine. [ABSTRACT FROM AUTHOR]

In the isolated rat vas deferens stimulated at 0.2 Hz, [C]labelled 5′-AMP, 5′-ADP and 5′-ATP (10 μM) inhibited twitch responses, were broken down to [C]adenosine in the medium and incorporated into [C]adenine ribonucleotides in the tissue. Pretreatment of tissues with 6-(2-hydroxy-5-nitrobenzyl)-thioguanosine (NBTGR), a potent inhibitor of adenosine transport, potentiated the presynaptic inhibitory action of these 5′ nucleotides and reduced their incorporation in [C]adenine nucleotides, but did not alter the appearance of [C]adenosine in the medium. A series of 2′, 3′ and 5′-substituted adenine nucleotides (10 μM) inhibited the twitch responses of the vas deferens stimulated at 0.2 Hz. This effect was potentiated by NBTGR. Addition of exogenous adenosine deaminase very significantly reduced the inhibitory actions of adenosine, 5′-AMP, 5′-ADP and 5′-ATP and also reduced those of 2′, 5′-ADP, NAD and dePCoA. The inhibitory actions of the other 2′, 3′ and 5′ adenine nucleotides studied were not altered by exogenous adenosine deaminase. These results indicated that the presynaptic inhibitory actions of 5′-AMP, 5′-ADP and 5′-ATP in rat vas deferens predominantly result from their prior hydrolysis to adenosine whereas the 2′, 3′ and 5′-substituted adenine nucleotides appear to act mainly directly to inhibit transmitter release. [ABSTRACT FROM AUTHOR]

In the isolated rat vas deferens, various 2-substituted adenosine derivatives and adenosine inhibited contractions elicited by field stimulation but had little effect on responses to exogenous noradrenaline. 2-Chloroadenosine, 2-bromoadenosine, 2-hydroxyadenosine and 2-fluoroadenosine were all more potent than adenosine. Theophylline antagonized the action of the 2-substituted derivatives. The inhibitory action of adenosine was potentiated by dipyridamole, 2-amino-6-[(2-hydroxy-5-nitro)benzylthio]-9-β- d-ribofuranosylpurine (HNBTG) or 2′-deoxycoformycin while that of 2-chloroadenosine was not altered by any of these drugs or by phenoxybenzamine, atropine or indomethacin. Pretreatment of the vas deferens with both HNBTG and 2′-deoxycoformycin eliminated the difference in inhibitory potency between adenosine and 2-chloroadenosine. These results indicate that 2-substituted adenosine derivatives, like adenosine, produce inhibition of transmission by acting on a presynaptic site which can be blocked by theophylline. The high apparent potency of 2-chloroadenosine compared to adenosine appears to be duc to the former being neither taken up nor deaminated, while the apparent potency of adenosine is masked by uptake and deamination in this tissue. [ABSTRACT FROM AUTHOR]

Sugar intake rates of captive Australian honeyeaters (Meliphagidae) feeding at artificial flowers varied across species, and as a function of nectar volume and concentration within each species. Red Wattlebirds ( Anthochaera carunculata, 110 g), achieved higher intake rates than New Holland Honeyeaters ( Phylidonyris novaehollandiae, 20 g), and both achieved higher rates than Eastern Spinebills ( Acanthorhynchus tenuirostris, 10 g). These results reflect differences in bill and tongue dimensions as well as in body mass. Sugar intake rates for all three species increased with volume (5-50 μl) at any given concentration (10-60% mass/mass sucrose). For a given volume, sugar intake rates peaked at intermediate concentrations: 40-50% for the two larger species, and 30-40% for the smallest species. Published studies for other nectarivores foraging at unlimited volume feeders also show optimal nectar concentrations of 30-50%. However, biophysical theory predicts optima at 20-26% for small volumes, and plants presumed to be adapted for bird-pollination often have dilute nectar (20-30%). To explore this discrepancy further, we presented New Holland Honeyeaters with a range of sucrose concentrations (10-50%) using two presentation schemes. In the first we varied concentration but kept volume constant, thus varying gross sugar reward available in each concentration. This gave maximum sugar intake rates at 50%. In the second we varied both volume and concentration so that gross sugar rewards were equal for all solutions, decoupling high concentrations and large sugar rewards. This gave optima at 20%. We argue that variation among plants in nature more closely resembles the latter, 'equal sugar presentation' scheme, and therefore, that dilute nectars may indeed represent adaptations for bird pollination. [ABSTRACT FROM AUTHOR]

Knowledge about the movement ecology of endangered species is needed to identify biologically important areas and the spatio-temporal scale of potential human impacts on species. Blue whales (Balaenoptera musculus) are endangered due to twentieth century whaling and currently threatened by human activities. In Australia, they feed in the Great Southern Australian Coastal Upwelling System (GSACUS) during the austral summer. We investigate their movements, occupancy, behaviour, and environmental drivers to inform conservation management. Thirteen whales were satellite tagged, biopsy sampled and photo-identified in 2015. All were genetically confirmed to be of the pygmy subspecies (B. m. brevicauda). In the GSACUS, whales spent most of their time over the continental shelf and likely foraging in association with several seascape variables (sea surface temperature variability, depth, wind speed, sea surface height anomaly, and chlorophyll a). When whales left the region, they migrated west and then north along the Australian coast until they reached West Timor and Indonesia, where their movements indicated breeding or foraging behaviour. These results highlight the importance of the GSACUS as a foraging ground for pygmy blue whales inhabiting the eastern Indian Ocean and indicate the whales' migratory route to proposed breeding grounds off Indonesia. Information about the spatio-temporal scale of potential human impacts can now be used to protect this little-known subspecies of blue whale. [ABSTRACT FROM AUTHOR]