696 research outputs found

    Coral Colony-Scale Rugosity Metrics and Applications for Assessing Temporal Trends in the Structural Complexity of Coral Reefs.

    Get PDF
    Globally, coral reefs are experiencing reductions in structural complexity, primarily due to a loss of key reef building taxa. Monitoring these changes is difficult due to the time-consuming nature of in-situ measurements and lack of data concerning coral genus-specific contributions to reef structure. This research aimed to develop a new technique that uses coral colony level data to quantify reef rugosity (a 3-dimensional measure of reef structure) from three sources of coral survey data: 2D video imagery, line intercept data and UAV imagery. A database of coral colony rugosity data, comparing coral colony planar and contour length for 40 coral genera, 14 morphotypes and 9 abiotic reef substrates, was created using measurements from the Great Barrier Reef and Natural History Museum. Mean genus rugosity was identified as a key trait related to coral life history strategy. Linear regression analyses (y = mx) revealed statistically significant (p < 0.05) relationships between coral colony size and rugosity for every coral genus, morphotype and substrate. The gradient governing these relationships was unique for each coral taxa, ranging from mean = 1.23, for (encrusting) Acanthastrea, to m = 3.84, for (vase-shape) Merulina. These gradients were used as conversion factors to calculate reef rugosity from linear distances measured in video transects of both artificial reefs, used as a control test, and in-situ natural coral reefs, using Kinovea software. This calculated, ‘virtual’ rugosity had a strong, positive relationship with in-situ microscale rugosity (r2 = 0.96) measured from the control transects, but not with that measured at the meso-scale in natural, highly heterogeneous reef environments (r2 < 0.2). This showed that the technique can provide accurate rugosity information when considered at the coral colony level. The conversion factors were also applied to historic line intercept data from the Seychelles, where temporal changes in calculated rugosity were consistent with changes in coral cover between 2008 and 2017. Finally, on application to 2,283 corals digitised from UAV imagery of the Maldives, the conversion factors enabled calculation of rugosity for three 100 m2 reef areas and prediction of how this rugosity will decrease during two future scenarios of coral reef degradation and community change. The study highlights that the application of genera-specific coral rugosity data to both new and existing coral reef survey datasets could be a valuable tool for monitoring reef structural complexity over large spatial scales

    The influence of auditory feedback on speed choice, violations and comfort in a driving simulation game

    Get PDF
    Two experiments are reported which explore the relationships between auditory feedback (engine noise), speed choice, driving violations and driver comfort. Participants played a driving simulation game with different levels of auditory feedback in the form of engine noise. In Experiment 1, a between-subjects design revealed that no noise and low levels of engine noise (65 dB(A)) resulted in participants driving at faster speeds than in the medium (75 dB(A)) and high (85 dB(A)) levels of engine noise conditions. The low noise feedback conditions were also associated with decreases in driver comfort. Experiment 2 also demonstrated that low levels of engine noise feedback (no feedback and 70 dB(A)) were associated with increases in driving speed, and driving violations relative to higher levels of feedback (75 dB(A) and 80 dB(A)). Implications exist for current car manufacturing trends which emphasise a growing increase in noise insulation for the driver. © 2011 Elsevier Ltd. All rights reserved

    The syntax of generics and the absence of generic articles

    Get PDF
    Cross-linguistically, no language has a dedicated generic article. To address why this is, I decompose GEN into its quantificational and modal components and locate them inside nominal structure. Adopting an event licensing analysis of pre- and post-verbal bare subjects in Modern Hebrew, I use the restriction of pre-verbal bare subjects to generic interpretations and unacceptability of pre-verbal bare singulars to argue that the quantificational component of GEN is best analyzed as a D-quantifier. Evidence from adnominal conditionals further identifies a modal source for GEN within the nominal, which I suggest is adjectival and derived from a reduced relative clause source. I propose that the formation of generic articles is blocked by the non-local (e.g. non-spanning) relationship between these quantificational and modal components

    Dissecting the complex environment of a distant quasar with MUSE

    Get PDF
    High redshift quasars can be used to trace the early growth of massive galaxies and may be triggered by galaxy-galaxy interactions. We present MUSE science verification data on one such interacting system consisting of the well-studied z=3.2 PKS1614+051 quasar, its AGN companion galaxy and bridge of material radiating in Lyalpha between the quasar and its companion. We find a total of four companion galaxies (at least two galaxies are new discoveries), three of which reside within the likely virial radius of the quasar host, suggesting that the system will evolve into a massive elliptical galaxy by the present day. The MUSE data are of sufficient quality to split the extended Lyalpha emission line into narrow velocity channels. In these the gas can be seen extending towards each of the three neighbouring galaxies suggesting that the emission-line gas originates in a gravitational interaction between the galaxies and the quasar host. The photoionization source of this gas is less clear but is probably dominated by the two AGN. The quasar's Lyalpha emission spectrum is double-peaked, likely due to absorbing neutral material at the quasar's systemic redshift with a low column density as no damping wings are present. The spectral profiles of the AGN and bridge's Lyalpha emission are also consistent with absorption at the same redshift indicating this neutral material may extend over > 50 kpc. The fact that the neutral material is seen in the line of sight to the quasar and transverse to it, and the fact that we see the quasar and it also illuminates the emission-line bridge, suggests the quasar radiates isotropically and any obscuring torus is small. These results demonstrate the power of MUSE for investigating the dynamics of interacting systems at high redshift.Comment: 9 pages, 6 figures, published in MNRA

    Glen E. Dickenson and M. W. Husband to Governor Ross Barnett, 28 September 1962

    Get PDF
    Senders discuss the attempted invasions of both Cuba and Mississippi.https://egrove.olemiss.edu/west_union_gov/1057/thumbnail.jp

    Identifying clustering at high redshift through actively star-forming galaxies

    Get PDF
    Identifying galaxy clustering at high redshift (i.e. z > 1) is essential to our understanding of the current cosmological model. However, at increasing redshift, clusters evolve considerably in star-formation activity and so are less likely to be identified using the widely-used red sequence method. Here we assess the viability of instead identifying high redshift clustering using actively star-forming galaxies (SMGs associated with over-densities of BzKs/LBGs). We perform both a 2- and 3-D clustering analysis to determine whether or not true (3D) clustering can be identified where only 2D data are available. As expected, we find that 2D clustering signals are weak at best and inferred results are method dependant. In our 3D analysis, we identify 12 SMGs associated with an over-density of galaxies coincident both spatially and in redshift - just 8% of SMGs with known redshifts in our sample. Where an SMG in our target fields lacks a known redshift, their sightline is no more likely to display clustering than blank sky fields; prior redshift information for the SMG is required to identify a true clustering signal. We find that the strength of clustering in the volume around typical SMGs, while identifiable, is not exceptional. However, we identify a small number of highly clustered regions, all associated with an SMG. The most notable of these, surrounding LESSJ033336.8-274401, potentially contains an SMG, a QSO and 36 star-forming galaxies (a > 20sig over-density) all at z~1.8. This region is highly likely to represent an actively star-forming cluster and illustrates the success of using star-forming galaxies to select sites of early clustering. Given the increasing number of deep fields with large volumes of spectroscopy, or high quality and reliable photometric redshifts, this opens a new avenue for cluster identification in the young Universe.Comment: 24 pages, 14 figures, accepted MNRA

    Compositional states

    Get PDF
    Whether a transitive stative predicate licenses an existential interpretaiton of its subject (EIS) depends on the type of object it has. While previous theories have related this to the object's ability to function as a topic, I present evidence that the quantized/homogeneous distinction between objects better captures EIS and propose an event composition analysis of EIS for transitive stative predicates. This analysis points to the aspectual nature of EIS and also illuminates other aspectual behaviors of stage-level/individual-level states

    Prediction of phonological and gender information:An event-related potential study in Italian

    Get PDF
    Do people predict different aspects of a predictable word to the same extent? We tested prediction of phonological and gender information by creating phonological and gender mismatches between an article and a predictable noun in Italian. Native Italian speakers read predictive sentence contexts followed by the expected noun (e.g., un incidente: ‘accident’) or another plausible, but unexpected noun, either beginning with a different phonological class (consonant vs. vowel, e.g., uno scontro: ‘collision’; phonological mismatch) or belonging to a different gender class (e.g., un'inondazione: ‘flooding’; gender mismatch). Phonological mismatch articles elicited greater negativity than expected articles at posterior channels around 450–800 ms post-stimulus. In contrast, gender mismatch articles elicited greater negativity than expected articles at left posterior channels around 250–800 ms. Unexpected nouns showed an N400 effect followed by frontal positivity relative to expected nouns. The earlier effect for the gender mismatch articles suggests that people are quicker or more likely to pre-activate gender information vs. phonological information of a predictable word. We interpret the results with respect to production-based prediction accounts

    An Analysis of Overstory Tree Canopy Cover in Sites Occupied by Native and Introduced Cottontails in the Northeastern United States with Recommendations for Habitat Management for New England Cottontail

    Get PDF
    The New England cottontail (Sylvilagus transitionalis) is a high conservation priority in the Northeastern United States and has been listed as a candidate species under the Endangered Species Act. Loss of early successional habitat is the most common explanation for the decline of the species, which is considered to require habitat with dense low vegetation and limited overstory tree canopy. Federal and state wildlife agencies actively encourage landowners to create this habitat type by clearcutting blocks of forest. However, there are recent indications that the species also occupies sites with moderate overstory tree canopy cover. This is important because many landowners have negative views about clearcutting and are more willing to adopt silvicultural approaches that retain some overstory trees. Furthermore, it is possible that clearcuts with no overstory canopy cover may attract the eastern cottontail (S. floridanus), an introduced species with an expanding range. The objective of our study was to provide guidance for future efforts to create habitat that would be more favorable for New England cottontail than eastern cottontail in areas where the two species are sympatric. We analyzed canopy cover at 336 cottontail locations in five states using maximum entropy modelling and other statistical methods. We found that New England cottontail occupied sites with a mean overstory tree canopy cover of 58% (SE±1.36), and was less likely than eastern cottontail to occupy sites with lower overstory canopy cover and more likely to occupy sites with higher overstory canopy cover. Our findings suggest that silvicultural approaches that retain some overstory canopy cover may be appropriate for creating habitat for New England cottontail. We believe that our results will help inform critical management decisions for the conservation of New England cottontail, and that our methodology can be applied to analyses of habitat use of other critical wildlife species

    Impact of phosphate dosing on the microbial ecology of drinking water distribution systems: fieldwork studies in chlorinated networks

    Get PDF
    Phosphate is routinely dosed to ensure regulatory compliance for lead in drinking water distribution systems. Little is known about the impact of the phosphate dose on the microbial ecology in these systems and in particular the endemic biofilms. Disturbance of the biofilms and embedded material in distribution can cause regulatory failures for turbidity and metals. To investigate the impact of phosphate on developing biofilms, pipe wall material from four independent pipe sections was mobilised and collected using two twin-flushing operations a year apart in a chlorinated UK network pre- and post-phosphate dosing. Intensive monitoring was undertaken, including turbidity and water physico-chemistry, traditional microbial culture-based indicators, and microbial community structure via sequencing the 16S rRNA gene for bacteria and the ITS2 gene for fungi. Whole metagenome sequencing was used to study shifts in functional characteristics following the addition of phosphate. As an operational consequence, turbidity responses from the phosphate-enriched water were increased, particularly from cast iron pipes. Differences in the taxonomic composition of both bacteria and fungi were also observed, emphasising a community shift towards microorganisms able to use or metabolise phosphate. Phosphate increased the relative abundance of bacteria such as Pseudomonas, Paenibacillus, Massilia, Acinetobacter and the fungi Cadophora, Rhizophagus and Eupenicillium. Whole metagenome sequencing showed with phosphate a favouring of sequences related to Gram-negative bacterium type cell wall function, virions and thylakoids, but a reduction in the number of sequences associated to vitamin binding, methanogenesis and toxin biosynthesis. With current faecal indicator tests only providing risk detection in bulk water samples, this work improves understanding of how network changes effect microbial ecology and highlights the potential for new approaches to inform future monitoring or control strategies to protect drinking water quality
    • 

    corecore