82 results on '"Richard D. Evans"'
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52. Surveillance and Poaching on Inshore Reefs of the Great Barrier Reef Marine Park
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Richard D. Evans, David H. Williamson, K.L.F. Davis, and Garry R. Russ
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Fishery ,geography ,Multiple use ,geography.geographical_feature_category ,Recreational fishing ,Environmental Chemistry ,Poaching ,Marine park ,Zoning ,Coral reef protection ,Reef ,Great barrier reef ,General Environmental Science - Abstract
The Great Barrier Reef (GBR), Australia, is managed under the GBR Marine Park Act (1975) and is seen as a shining example of marine resource management. The principle tool of management is zoning for multiple use. We examined surveillance and illegal fishing around two inshore islands (Magnetic and Orpheus) of the GBR Marine Park in 2000/2001. Both islands are near Townsville, the largest city adjacent to the GBR. Surveillance effort was low, with vessels present on only 16% of days of the year. Measurable but low levels of illegal recreational fishing occurred within no-take zones. Levels decreased with increasing surveillance effort. Thus zoning was not completely successful in protecting fish targeted by fisheries, even within the most highly enforced sections of the Park. The expansion of no-take zones in 2004 from 4.6% to 33.4% of the area of the 358,000 km2 Park represents a considerable challenge for future surveillance and enforcement.
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- 2004
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53. Larger biomass of targeted reef fish in no-take marine reserves on the Great Barrier Reef, Australia
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Richard D. Evans and Garry R. Russ
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geography ,geography.geographical_feature_category ,Ecology ,biology ,Coral reef fish ,Plectropomus ,Fishing ,Marine reserve ,Aquatic Science ,biology.organism_classification ,Fishery ,Lutjanus carponotatus ,Benthic zone ,Fisheries management ,Reef ,Nature and Landscape Conservation - Abstract
1. An expansion of no-take marine reserve zones of Australia's 348 000 km2 Great Barrier Reef (GBR) Marine Park from 4.6% to 33.4% of the park area is proposed in 2004. However, limited evidence currently exists that no-take marine reserves on the GBR have increased abundance of reef fish targeted by fisheries. This study provides such evidence for inshore reefs of the GBR. 2. Underwater visual surveys were used to estimate the effect of no-take reserves on abundance of species targeted by hook-and-line fisheries around the Palm, Whitsunday and Keppel Islands, spanning 600 km of the length of the GBR. The reserves had been zoned no fishing for 14 yr. 3. Densities of Plectropomus spp. and Lutjanus carponotatus, both targeted by fisheries, were much higher in protected zones than fished zones in two of the three island groups. Plectropomus spp. were 3.6 and 2.3 times more abundant in protected than fished zones of the Palm and Whitsunday island groups. L. carponotatus were 2.3 and 2.2 times more abundant in protected zones than fished zones of the Whitsunday and Keppel island groups. 4. The biomasses of Plectropomus spp. and L. carponotatus were significantly greater (3.9 and 2.6 times respectively) in the protected zones than fished zones at all three island groups. 5. Legal minimum sizes of Plectropomus spp. and L. carponotatus are 38 cm and 25 cm TL respectively. There were significantly higher densities and biomasses of Plectropomus spp. >35 cm TL (density: 3.8 times; biomass: 5.1 times) and L. carponotatus >25 cm TL (density: 4.2 times; biomass: 5.3 times) in protected zones than fished zones at all three island groups. 6. No significant difference in abundance between protected and fished zones was found for two species not captured by fisheries (Siganus doliatus and Chaetodon aureofasciatus), and there were no significant differences in benthic characteristics between protected and fished zones. 7. Results suggest that no-take marine reserves have increased stock biomass of targeted fish species on inshore GBR reefs.
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- 2004
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54. The effects of marine reserve protection on the trophic relationships of reef fishes on the Great Barrier Reef
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Nicholas A. J. Graham, Richard D. Evans, and Garry R. Russ
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geography ,geography.geographical_feature_category ,Coral reef fish ,Ecology ,Plectropomus ,Health, Toxicology and Mutagenesis ,Marine reserve ,Coral reef ,Management, Monitoring, Policy and Law ,Biology ,biology.organism_classification ,Pollution ,Fishery ,Forage fish ,Fisheries management ,Coral reef protection ,Nature and Landscape Conservation ,Water Science and Technology ,Coral trout - Abstract
What are the effects of no-take marine reserves on trophic relationships of coral reef fish? Previous studies often have lacked detailed dietary information on major predators, and have often been confounded by differences in habitat complexity between reserve and fished sites. This study investigates the effects of marine reserve protection on predator-prey interactions of coral reef fish on the inshore islands of the Great Barrier Reef (GBR). The abundance of species of prey fish of Plectropomus leopardus (Serranidae), a piscivore and the major target of the hook and line fisheries on the GBR, were estimated in protected and fished zones. These prey species were identified from previous detailed studies of the diet of P. leopardus. Fish populations and habitat characteristics were surveyed by underwater visual census. Previous studies had determined that the biomass of P. leopardus was 3–4 times higher in protected than fished zones in the Whitsunday and Palm Islands, central GBR, after 14 years of protection. Eight of the nine prey species had a higher density within fished zones than protected zones, six significantly so. The density of all prey fish was twice that in the fished than the protected zone (p < 0.001). There were no significant differences in availability of different sized refuge holes, structural complexity or live coral cover between zones. Thus, important attributes of habitat complexity did not confound the comparisons between reserve and fished zones. Finally, a significant negative correlation (r = 0.46) between coral trout biomass and summed prey fish biomass suggested that predation may be an important structuring process in this system. The results have implications for the conservation of fishery targets and their prey. The study highlights the potential ecosystem implications of the use of no-take marine reserves as conservation and fisheries management tools.
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- 2003
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55. A tumor-associated β1 integrin mutation that abrogates epithelial differentiation control
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Richard D. Evans, Fiona M. Watt, Alistair James Henry, Martyn K. Robinson, Vivienne C. Perkins, and Paul E. Stephens
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Keratinocytes ,Models, Molecular ,Recombinant Fusion Proteins ,Cellular differentiation ,Molecular Sequence Data ,Mutant ,Integrin ,Chick Embryo ,Ligands ,medicine.disease_cause ,integrin ,keratinocyte ,differentiation ,adhesion ,tumor ,CD49c ,Article ,Cell Movement ,Cell Adhesion ,Tumor Cells, Cultured ,medicine ,Animals ,Humans ,Point Mutation ,Amino Acid Sequence ,Cell adhesion ,Mutation ,biology ,Integrin beta1 ,Cell Differentiation ,Cell Biology ,Protein Structure, Tertiary ,Cell biology ,Protein Subunits ,Integrin alpha M ,Carcinoma, Squamous Cell ,biology.protein ,Mitogen-Activated Protein Kinases ,Signal transduction ,Sequence Alignment ,Protein Binding ,Signal Transduction - Abstract
SCC4 human keratinocytes are derived from a squamous cell carcinoma of the tongue and undergo very little spontaneous differentiation. Introduction of a wild-type beta 1 integrin subunit into SCC4 cells stimulates differentiation, suggesting either that the cells have a defect in the integrin signaling pathways that control differentiation or that the beta1 subunit itself is defective. Here we describe a heterozygous mutation in the SCC4 beta 1 subunit. The mutation, T188I, maps to the I-like domain. It results in constitutive activation of ligand binding, irrespective of the partner alpha subunit, in solid phase assays with recombinant protein and in living cells. The mutation promotes cell spreading, but not proliferation, motility, or invasiveness. It results in sustained activation of Erk MAPK independent of cell spreading. When introduced into SCC4 keratinocytes, the wild-type beta1 integrin stimulates differentiation, whereas the mutant is inactive. Activation of beta 1 integrins in normal keratinocytes also suppresses differentiation. These results establish, for the first time, mutation as a mechanism by which integrins can contribute to neoplasia, because the degree of differentiation in epithelial cancers is inversely correlated with prognosis. They also provide new insights into how integrins regulate keratinocyte differentiation.
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- 2003
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56. Derelict fishing line provides a useful proxy for estimating levels of non-compliance with no-take marine reserves
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David H. Williamson, Jos K. Hill, Richard D. Evans, Garry R. Russ, and Daniela M. Ceccarelli
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Marine conservation ,Environmental Impacts ,Conservation of Natural Resources ,Oceans and Seas ,Fishing ,Biodiversity ,Fisheries ,lcsh:Medicine ,Marine Biology ,Research and Analysis Methods ,Fishing line ,Marine Conservation ,Marine Monitoring ,Animals ,Longitudinal Studies ,lcsh:Science ,Reef ,geography ,Multidisciplinary ,geography.geographical_feature_category ,Ecology ,Coral Reefs ,lcsh:R ,Marine reserve ,fungi ,Ecology and Environmental Sciences ,Australia ,Fishes ,Quantitative Analysis ,Biology and Life Sciences ,Fisheries Science ,Coral reef ,Fishery ,Environmental Management ,Habitat ,Research Design ,lcsh:Q ,Environmental Protection ,Research Article - Abstract
No-take marine reserves (NTMRs) are increasingly being established to conserve or restore biodiversity and to enhance the sustainability of fisheries. Although effectively designed and protected NTMR networks can yield conservation and fishery benefits, reserve effects often fail to manifest in systems where there are high levels of non-compliance by fishers (poaching). Obtaining reliable estimates of NTMR non-compliance can be expensive and logistically challenging, particularly in areas with limited or non-existent resources for conducting surveillance and enforcement. Here we assess the utility of density estimates and re-accumulation rates of derelict (lost and abandoned) fishing line as a proxy for fishing effort and NTMR non-compliance on fringing coral reefs in three island groups of the Great Barrier Reef Marine Park (GBRMP), Australia. Densities of derelict fishing line were consistently lower on reefs within old (>20 year) NTMRs than on non-NTMR reefs (significantly in the Palm and Whitsunday Islands), whereas line densities did not differ significantly between reefs in new NTMRs (5 years of protection) and non-NTMR reefs. A manipulative experiment in which derelict fishing lines were removed from a subset of the monitoring sites demonstrated that lines re-accumulated on NTMR reefs at approximately one third (32.4%) of the rate observed on non-NTMR reefs over a thirty-two month period. Although these inshore NTMRs have long been considered some of the best protected within the GBRMP, evidence presented here suggests that the level of non-compliance with NTMR regulations is higher than previously assumed.
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- 2014
57. Novel hypoglycemic injury mechanism: N-methyl-D-aspartate receptor-mediated white matter damage
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Xin, Yang, Margaret A, Hamner, Angus M, Brown, Richard D, Evans, Zu-Cheng, Ye, Shengdi, Chen, and Bruce R, Ransom
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Aspartic Acid ,Glycine ,Brain ,Glutamic Acid ,Hydrogen-Ion Concentration ,Kynurenic Acid ,Receptors, N-Methyl-D-Aspartate ,Hypoglycemia ,Article ,Mice, Inbred C57BL ,Disease Models, Animal ,Mice ,Leukoencephalopathies ,Optic Nerve Injuries ,Quinoxalines ,Excitatory Amino Acid Agonists ,Animals ,Calcium ,Lactic Acid ,Excitatory Amino Acid Antagonists ,alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid ,Glycogen - Abstract
Hypoglycemia is a common adverse event and can injure central nervous system (CNS) white matter (WM). We determined whether glutamate receptors were involved in hypoglycemic WM injury.Mouse optic nerves (MON), CNS WM tracts, were maintained at 37°C with oxygenated artificial cerebrospinal fluid (ACSF) containing 10mM glucose. Aglycemia was produced by switching to 0 glucose ACSF. Supramaximal compound action potentials (CAPs) were elicited using suction electrodes, and axon function was quantified as the area under the CAP. Amino acid release was measured using high-performance liquid chromatography. Extracellular lactate concentration ([lactate(-)]o) was measured using an enzyme electrode.About 50% of MON axons were injured after 60 minutes of aglycemia (90% after 90 minutes); injury extent was not affected by animal age. Blockade of N-methyl-D-aspartate (NMDA)-type glutamate receptors improved recovery after 90 minutes of aglycemia by 250%. Aglycemic injury was increased by reducing [Mg(2+)]o or increasing [glycine]o , and decreased by lowering pHo , expected results for NMDA receptor-mediated injury. pHo increased during aglycemia due to a drop in [lactate(-)]o. Aglycemic injury was dramatically reduced in the absence of [Ca(2+)]o. Extracellular aspartate, a selective NMDA receptor agonist, increased during aglycemia ([glutamate]o fell).Aglycemia injured WM by a unique excitotoxic mechanism involving NMDA receptors (located primarily on oligodendrocytes). During WM aglycemia, the selective NMDA agonist aspartate is released, probably from astrocytes. Injury is mediated by Ca(2+) influx through aspartate-activated NMDA receptors made permeable by an accompanying alkaline shift in pHo caused by a fall in [lactate(-)]o. These insights have important clinical implications.
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- 2013
58. Glycogen function in adult central and peripheral nerves
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Richard D, Evans, Angus M, Brown, and Bruce R, Ransom
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Adult ,Neurons ,Astrocytes ,Action Potentials ,Animals ,Humans ,Optic Nerve ,Schwann Cells ,Energy Metabolism ,Sciatic Nerve ,Axons ,Glycogen - Abstract
We studied the roles of glycogen in axonal pathways of the central nervous system (CNS) and peripheral nervous system (PNS). By using electrophysiological recordings, in combination with biochemical glycogen assay, it was possible to determine whether glycogen was crucial to axon function under different conditions. Glycogen was present both in mouse optic nerve (MON) and in mouse sciatic nerve (MSN). Aglycemia caused loss of the compound action potential (CAP) in both pathways after a latency of 15 min (MON) and 120 min for myelinated axons (A fibers) in the MSN. With the exception of unmyelinated axons (C fibers) in the MSN, CAP decline began when usable glycogen was exhausted. Glycogen was located in astrocytes in the MON and in myelinating Schwann cells in the MSN; it was absent from the Schwann cells surrounding unmyelinated C fibers. In MON, astrocytic glycogen is metabolized to lactate and "shuttled" to axons to support metabolism. The ability of lactate to support A fiber conduction in the absence of glucose suggests a common pathway in both the CNS and the PNS. Lactate is released from MON and MSN in substantial quantities. That lactate levels fall in MSN in the presence of diaminobenzidine, which inhibits glycogen phosphorylase, strongly suggests that glycogen metabolism contributes to lactate release under resting conditions. Glycogen is a "backup" energy substrate in both the CNS and the PNS and, beyond sustaining excitability during glucose deprivation, has the capacity to subsidize the axonal energy demands during times of intense activity in the presence of glucose.
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- 2012
59. Schwann cell glycogen selectively supports myelinated axon function
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Richard D. Evans, Bruce R. Ransom, Angus M. Brown, and Joel A. Black
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Male ,Time Factors ,Schwann cell ,Action Potentials ,Biology ,In Vitro Techniques ,Nerve Fibers, Myelinated ,Article ,law.invention ,chemistry.chemical_compound ,Mice ,Microscopy, Electron, Transmission ,law ,Neurofilament Proteins ,medicine ,Extracellular ,Animals ,Lactic Acid ,Axon ,Myelin Sheath ,Glycogen ,Glycogen Phosphorylase ,S100 Proteins ,Sciatic Nerve ,Electric Stimulation ,Compound muscle action potential ,Cell biology ,Electrophysiology ,medicine.anatomical_structure ,Glucose ,nervous system ,Neurology ,chemistry ,Neurology (clinical) ,Sciatic nerve ,Schwann Cells ,Electron microscope ,Energy Metabolism ,Neuroscience - Abstract
Objective: Interruption of energy supply to peripheral axons is a cause of axon loss. We determined whether glycogen was present in mammalian peripheral nerve, and whether it supported axon conduction during aglycemia. Methods: We used biochemical assay and electron microscopy to determine the presence of glycogen, and electrophysiology to monitor axon function. Results: Glycogen was present in sciatic nerve, its concentration varying directly with ambient glucose. Electron microscopy detected glycogen granules primarily in myelinating Schwann cell cytoplasm, and these diminished after exposure to aglycemia. During aglycemia, conduction failure in large myelinated axons (A fibers) mirrored the time course of glycogen loss. Latency to compound action potential (CAP) failure was directly related to nerve glycogen content at aglycemia onset. Glycogen did not benefit the function of slow-conducting, small-diameter unmyelinated axons (C fibers) during aglycemia. Blocking glycogen breakdown pharmacologically accelerated CAP failure during aglycemia in A fibers, but not in C fibers. Lactate was as effective as glucose in supporting sciatic nerve function, and was continuously released into the extracellular space in the presence of glucose and fell rapidly during aglycemia. Interpretation: Our findings indicated that glycogen is present in peripheral nerve, primarily in myelinating Schwann cells, and exclusively supports large-diameter, myelinated axon conduction during aglycemia. Available evidence suggests that peripheral nerve glycogen breaks down during aglycemia and is passed, probably as lactate, to myelinated axons to support function. Unmyelinated axons are not protected by glycogen and are more vulnerable to dysfunction during periods of hypoglycemia. ANN NEUROL 2012;72:406–418.
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- 2012
60. Digitise this! A quick and easy remote sensing method to monitor the daily extent of dredge plumes
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George Shedrawi, Peter Fearns, Bart Huntley, M. Broomhall, Kathy Murray, Stuart N. Field, James A. Y. Moore, Richard D. Evans, Daniel Marrable, and Lachlan I. W. McKinna
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Geographic information system ,lcsh:Medicine ,Marine and Aquatic Sciences ,Oceanography ,Marine Monitoring ,Water Quality ,Environmental monitoring ,Geoinformatics ,Humans ,lcsh:Science ,Radiometry ,Environmental Geology ,Remote sensing ,Physics ,Multidisciplinary ,Remote Sensing Imagery ,business.industry ,lcsh:R ,Marine Ecology ,Western Australia ,Floods ,Plume ,Waves and shallow water ,Benthic zone ,Remote Sensing Technology ,Computer Science ,Geographic Information Systems ,Earth Sciences ,lcsh:Q ,Sediment ,Stage (hydrology) ,Moderate-resolution imaging spectroradiometer ,business ,Marine Geology ,Environmental Sciences ,Coastal Ecology ,Environmental Monitoring ,Research Article ,Physical Oceanography - Abstract
Technological advancements in remote sensing and GIS have improved natural resource managers' abilities to monitor large-scale disturbances. In a time where many processes are heading towards automation, this study has regressed to simple techniques to bridge a gap found in the advancement of technology. The near-daily monitoring of dredge plume extent is common practice using Moderate Resolution Imaging Spectroradiometer (MODIS) imagery and associated algorithms to predict the total suspended solids (TSS) concentration in the surface waters originating from floods and dredge plumes. Unfortunately, these methods cannot determine the difference between dredge plume and benthic features in shallow, clear water. This case study at Barrow Island, Western Australia, uses hand digitising to demonstrate the ability of human interpretation to determine this difference with a level of confidence and compares the method to contemporary TSS methods. Hand digitising was quick, cheap and required very little training of staff to complete. Results of ANOSIM R statistics show remote sensing derived TSS provided similar spatial results if they were thresholded to at least 3 mg L(-1). However, remote sensing derived TSS consistently provided false-positive readings of shallow benthic features as Plume with a threshold up to TSS of 6 mg L(-1), and began providing false-negatives (excluding actual plume) at a threshold as low as 4 mg L(-1). Semi-automated processes that estimate plume concentration and distinguish between plumes and shallow benthic features without the arbitrary nature of human interpretation would be preferred as a plume monitoring method. However, at this stage, the hand digitising method is very useful and is more accurate at determining plume boundaries over shallow benthic features and is accessible to all levels of management with basic training.
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- 2012
61. Functions of Glycogen in the Central Nervous System
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Angus M. Brown, Richard D. Evans, and Bruce R. Ransom
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chemistry.chemical_compound ,medicine.anatomical_structure ,Glycogen breakdown ,Glycogen ,chemistry ,Central nervous system ,Extracellular ,medicine ,Energy metabolism ,Biology ,Mammalian brain ,Neuroscience ,Astrocyte - Abstract
Glycogen is present in the mammalian brain and has the intriguing feature of being predominantly located in astrocytes. Its importance was discounted for decades because of the presumption that it was found in concentrations too low to be meaningful. Recent studies have begun a full re-evaluation of the physiological role of brain glycogen and many of the findings have been unexpected. Moreover, they have helped expand our whole concept of brain energy metabolism. Among the new concepts is evidence that astrocyte glycogen can be broken down to an energy substrate, lactic acid most likely, that traverses the extracellular space and supports energy metabolism in adjacent neural elements under conditions of need. There is now strong evidence in favor of rapid coupling between active neurons and nearby astrocytes in terms of energy metabolism. Active neurons ‘communicate’ their energy needs, which are promptly met by astrocytes via glycogen breakdown. We are still learning the rules about this altruism among brain cells.
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- 2011
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62. Comparative Analysis of Regression Output Summary Statistics in Common Statistical Packages
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Richard D. Evans, Albert A. Okunade, and Cyril F. Chang
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Statistics and Probability ,General Mathematics ,Statistics ,Econometrics ,Regression analysis ,Cross-sectional regression ,Statistics, Probability and Uncertainty ,Software package ,Regression diagnostic ,Summary statistics ,Regression ,Mathematics - Abstract
An important question in applied statistics is whether statistical regression programs output distorted summary statistics (F and R 2) for a no-intercept regression model. Uyar and Erdem recently confirmed this problem using one of the premier statistical packages. This article extends the Uyar-Erdem experiment to eight common statistical and econometric regression packages. Only four of them warn users that the R 2 has been redefined for a model without an explicit intercept. Consequently, the problem Uyar and Erdem identified extends in varying degrees, ranging from mild to severe, to many other regression packages.
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- 1993
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63. Unit root and cointegration tests on the efficiency and biasedness of forward exchange rates
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C. S. Pyun and Richard D. Evans
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Economics and Econometrics ,Exchange rate ,Cointegration ,Autoregressive model ,Forward rate ,Statistics ,Economics ,Econometrics ,Unit root ,Finance - Abstract
This paper analyzes the stationarity of spot and forward exchange rates by testing for the presence of unit roots in the autoregressive process of the exchange rate time series. The results of the unit root and cointegration tests for forward exchange rates of six major currencies are inconsistent with earlier studies by others that found the existence of unit roots but the absence of cointegration. Our results show that realized spot rates are cointegrated with past forward rates. Both Dickey-Fuller and Augmented Dickey-Fuller tests affirm the unbiased forward rate hypothesis for 30- and 90-day forward rates. The Augmented Dickey-Fuller tests on the longer term forward rate, however, reveal the existence of cointegration that leads to the rejection of the hypothesis.
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- 1993
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64. A Transfer Function Analysis of Real Estate Capitalization Rates
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Richard D. Evans
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Earnings ,Financial economics ,Economics, Econometrics and Finance (miscellaneous) ,Business cycle ,Econometrics ,Economics ,Cost approach ,Real estate ,Stock market ,Autoregressive integrated moving average ,jel:L85 ,Income approach ,Capitalization rate - Abstract
A national multifamily and nonresidential real estate capitalization rate shows sensitivity to the analogous earnings/price ratio aggregated from the stock market. Both time series seen to have the same ARIMA characteristics. However, a transfer function analysis indicates that the sensitivity comes with a one quarter lag. Thus, even sophisticated real estate investors seem slow to adjust to changes in business cycle and monetary conditions that cause quicker changes in the stock market.
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- 1990
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65. Analyses of MT1-MMP activity in cells
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Richard D, Evans and Yoshifumi, Itoh
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Enzyme Precursors ,Tissue Inhibitor of Metalloproteinase-2 ,Tissue Inhibitor of Metalloproteinase-1 ,Blotting, Western ,Synovial Membrane ,Fluorescent Antibody Technique ,Metalloendopeptidases ,Dipeptides ,Fibroblasts ,Immunohistochemistry ,Collagen Type I ,Cell Line ,Arthritis, Rheumatoid ,Enzyme Activation ,Gelatinases ,Matrix Metalloproteinase 14 ,Gelatin ,Humans ,Protease Inhibitors - Abstract
Membrane-type 1 matrix metalloproteinase (MT1-MMP) is a type I transmembrane protein which exhibits biological activities on the cell surface. One of the characteristic functions of this enzyme is activation of proMMP-2 on the cell surface (1). This process can be monitored using gelatin zymography to detect the pro- and active forms of MMP-2. Cellular MT1-MMP activity can also be directly detected by in situ degradation of layers of either gelatin or collagen. By combining inhibitors, western blotting, and immunohistochemistry, one can detect and conclude the presence of MT1-MMP activity in the cells.
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- 2007
66. Sequence variation in the I-like domain of the beta1 integrin subunit in human oral squamous cell carcinomas
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Claire Taylor, Judith Jones, Fiona M. Watt, and Richard D. Evans
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Cancer Research ,Protein subunit ,Cell ,Integrin ,DNA Mutational Analysis ,Biology ,Ligands ,Polymerase Chain Reaction ,Extracellular matrix ,Exon ,Polymorphism (computer science) ,medicine ,Humans ,skin and connective tissue diseases ,chemistry.chemical_classification ,Polymorphism, Genetic ,Integrin beta1 ,DNA, Neoplasm ,Molecular biology ,Introns ,Amino acid ,stomatognathic diseases ,medicine.anatomical_structure ,Oncology ,chemistry ,biology.protein ,Carcinoma, Squamous Cell ,Mouth Neoplasms ,Keratinocyte - Abstract
We recently identified a heterozygous mutation in the beta1 integrin subunit of a squamous cell carcinoma (SCC) that maps to the I-like domain and activates ligand binding. To investigate the frequency of such mutations we screened 124 human oral SCCs. We identified six single nucleotide changes, all of which were also present in normal tissue, suggestive of polymorphisms. Two were in non-coding intronic sequences. Three were silent changes in exons. One caused a change in amino acid (A239V) that is unlikely to disturb integrin structure. We conclude that mutations in the beta1 I-like domain are uncommon in SCCs. However, population based studies of the polymorphisms we found may reveal an association with SCC development or prognosis.
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- 2004
67. Rapid increase in fish numbers follows creation of world's largest marine reserve network
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David H. Williamson, Ian Miller, Alistair J. Cheal, Hugh Sweatman, Garry R. Russ, Richard D. Evans, Andrew M. Dolman, and Michael J. Emslie
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Marine conservation ,Conservation of Natural Resources ,Time Factors ,Oceans and Seas ,Fishing ,Biodiversity ,Marine Biology ,Biology ,General Biochemistry, Genetics and Molecular Biology ,Species Specificity ,Animals ,Marine ecosystem ,Ecosystem ,Reef ,Population Density ,geography ,geography.geographical_feature_category ,Agricultural and Biological Sciences(all) ,Biochemistry, Genetics and Molecular Biology(all) ,Ecology ,Marine reserve ,Australia ,Anthozoa ,biology.organism_classification ,Perciformes ,Fishery ,General Agricultural and Biological Sciences ,Program Evaluation ,Coral trout - Abstract
SummaryNo-take marine reserves (NTMRs) are much advocated as a solution to managing marine ecosystems, protecting exploited species and restoring natural states of biodiversity [1,2]. Increasingly, it is becoming clear that effective marine conservation and management at ecosystem and regional scales requires extensive networks of NTMRs [1,2]. The world's largest network of such reserves was established on Australia's Great Barrier Reef (GBR) in 2004. Closing such a large area to all fishing has been socially and politically controversial, making it imperative that the effectiveness of this new reserve network be assessed. Here we report evidence, first, that the densities of the major target species of the GBR reef line fisheries were significantly higher in the new NTMRs, compared with fished sites, in just two years; and second, that the positive differences were consistent for multiple marine reserves over an unprecedented spatial scale (>1,000 km).
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- 2008
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68. Richard St Barbe Baker 1889–1982: A Keepsake Book For All Ages and Generations. Published by The Men of The Trees, 3 Over Avenue, Lesmurdie, Western Australia 6076, Australia: 72 pp., illustr., 21.5 × 15.5 × 1 cm, limited edition, all copies numbered. Published Oct. 1989, price hardback (Australian) $28.50 posted or paperback (Australian) $14 posted, 1989
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Richard D. Evans
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Health, Toxicology and Mutagenesis ,Management, Monitoring, Policy and Law ,Pollution ,Nature and Landscape Conservation ,Water Science and Technology - Published
- 1990
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69. A Test of Weak-Form Efficiency in Residential Real Estate Returns
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Michael Devaney, William Rayburn, and Richard D. Evans
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Transaction cost ,Economics and Econometrics ,education.field_of_study ,Financial economics ,Population ,Nonmarket forces ,Variance (accounting) ,Commission ,Urban planning ,Accounting ,Economics ,Econometrics ,education ,Database transaction ,Investment performance ,Finance - Abstract
This paper tests weak-form efficiency of residential real estate returns for the city of Memphis, Tennessee. The database for the study is comprised of the population of all sales of single-unit residential property over a fifteen-year period, 1970–1984. The city was divided into ten submarkets based on Memphis City Planning Commission planning districts. An analysis of variance procedure was utilized to stabilize the variance both within and across submarkets and nonmarket financing was partially controlled by eliminating transactions with loan-to-value ratios greater than 95%. The remaining transactions were then used to generate a mean return series. The advantage of the mean over the single transaction series used by Gau is that it represents the most likely outcome for the investor trying to duplicate investment performance since “property unique” features would be expected to cancel. Seven of the ten submarkets exhibited time patterns; however, after adjusting for transaction costs, all ten submarkets were determined weak-form efficient for the period 1970–1984. This was not true for the short horizon holding period, 1970–1975. In four sub-markets an asymmetric version of Alexander's filter rule was able to outperform a buy-and-hold, even for round- trip transaction costs as high as 10%.
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- 1987
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70. Ranking Occupations as Risky Income Prospects
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Richard D. Evans and Robert Weinstein
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Attractiveness ,Organizational Behavior and Human Resource Management ,Labour economics ,Public use ,Ranking ,Management of Technology and Innovation ,Strategy and Management ,Economics ,Stochastic dominance ,Sample (statistics) ,Census - Abstract
This study investigates the problem of how best to measure the income attractiveness of various occupations, allowing for the differences among occupations in their stability of income. Analyzing data for eleven occupations from the one percent Public Use Sample of the 1970 U.S. Census of Occupations, the authors demonstrate the weaknesses of measures used in previous studies and the advantages of using stochastic dominance analysis.
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- 1982
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71. An exercise in OPEC taxonomy
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Richard D. Evans
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Economics and Econometrics ,Knowledge management ,business.industry ,Taxonomy (general) ,business ,Psychology ,Law - Published
- 1983
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72. Residential Construction Volatility: A Seasonal and Cyclical Inventory Adjustment Analysis
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Richard D. Evans
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Stabilization policy ,Economics and Econometrics ,Market economy ,Specification ,Accounting ,Econometrics ,medicine ,Economics ,Housing starts ,Seasonality ,Volatility (finance) ,medicine.disease ,Finance - Abstract
The seasonality of inventories and the seasonality and cyclicality of sales of new single-family residences by speculative builders may be formally introduced into a partial production adjustment inventory model of housing starts. The theoretical results include variables that imply an interaction between seasonality and cyclicality. A specification error bias in the estimation of the partial adjustment coefficient is evaluated for models that exclude the interaction between seasonality and cyclicality. Stabilization policy is more complex when cyclical instability changes season to season. In this view, justification is found for a seasonal stabilization policy in housing.
- Published
- 1981
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73. A Comparative Study of Rabbits Maintained on Barley or Alfalfa
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W. D. Sansum, M. Louisa Long, Richard D. Evans, and Fritz Bischoff
- Subjects
Nutrition and Dietetics ,Animal science ,Urinary system ,Botany ,medicine ,Medicine (miscellaneous) ,Composition (visual arts) ,Urine ,Biology ,Hordeum ,medicine.disease ,biology.organism_classification ,Nephritis - Published
- 1932
- Full Text
- View/download PDF
74. Hormones in Cancer: VIII. Influence of the Hypophysis
- Author
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L. C. Maxwell, H. J. Ullmann, Fritz Bischoff, and Richard D. Evans
- Subjects
Cancer Research ,medicine.medical_specialty ,Pituitary gland ,business.industry ,Active principle ,Cancer ,medicine.disease ,Endocrinology ,medicine.anatomical_structure ,Oncology ,Internal medicine ,medicine ,Tumor growth ,business ,Hormone - Abstract
Introduction The present paper is a summation of results obtained leading to the conclusion that the pituitary gland may be concerned in neoplastic extension. Preliminary reports2 (1, 2, 3) of our earlier findings have been presented, and it was originally intended that further publication should be withheld until the results warranted some degree of finality as to conclusion. In the meantime others (4, 5, 6) have entered the field and new relations (7) of the anterior lobe hormones to each other have been established. It appeared timely, therefore, to present our evidence demonstrating the effect of the pituitary, since it is now clear that more ground must be covered before the mechanism of the hormonal influence of the pituitary upon neoplastic extension is elucidated. Plan of Study In studying the possible role of the pituitary in neoplastic extension, two methods are feasible: the active glandular principles may be administered, or the gland or fraction of the gland elaborating the active principle may be removed, and the effects upon tumor growth noted. We have resorted to roentgen irradiation of the pituitary region in an attempt to inhibit the normal function of the gland and have studied the effect of dosage of all the established active principles of the gland.
- Published
- 1934
- Full Text
- View/download PDF
75. Ischemic pain in exercising muscles
- Author
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Albert H. Elliot and Richard D. Evans
- Subjects
medicine.medical_specialty ,business.industry ,Physical therapy ,medicine ,Cardiology and Cardiovascular Medicine ,business ,Ischemic pain - Published
- 1936
- Full Text
- View/download PDF
76. CLINICAL AND ELECTROCARDIOGRAPHIC PICTURE OF CORONARY OCCLUSION PRODUCED BY RUPTURED ANEURYSM OF THE ABDOMINAL AORTA
- Author
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Richard D. Evans and Albert H. Elliot
- Subjects
medicine.medical_specialty ,Aneurysm ,business.industry ,Coronary occlusion ,medicine.artery ,Internal medicine ,Abdominal aorta ,medicine ,Cardiology ,General Medicine ,business ,medicine.disease - Published
- 1936
- Full Text
- View/download PDF
77. Expectations and Outcomes of Reserve Network Performance following Re-zoning of the Great Barrier Reef Marine Park
- Author
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Daniela M. Ceccarelli, Hugh Sweatman, Ian Miller, David H. Williamson, Michelle Jonker, Murray Logan, Michael J. Emslie, Kate Osborne, Garry R. Russ, M. Aaron MacNeil, Kerryn Johns, Anthony M. Ayling, Richard D. Evans, and Alistair J. Cheal
- Subjects
Conservation of Natural Resources ,Coral reef fish ,Trout ,General Biochemistry, Genetics and Molecular Biology ,Animals ,Aquaculture of coral ,Reef ,Ecosystem ,geography ,geography.geographical_feature_category ,biology ,Ecology ,Resilience of coral reefs ,Coral Reefs ,fungi ,Fishes ,technology, industry, and agriculture ,Coral reef ,Biodiversity ,biochemical phenomena, metabolism, and nutrition ,biology.organism_classification ,Anthozoa ,Fishery ,population characteristics ,General Agricultural and Biological Sciences ,Environmental issues with coral reefs ,Coral reef protection ,geographic locations ,Coral trout - Abstract
SummaryNetworks of no-take marine reserves (NTMRs) are widely advocated for preserving exploited fish stocks and for conserving biodiversity. We used underwater visual surveys of coral reef fish and benthic communities to quantify the short- to medium-term (5 to 30 years) ecological effects of the establishment of NTMRs within the Great Barrier Reef Marine Park (GBRMP). The density, mean length, and biomass of principal fishery species, coral trout (Plectropomus spp., Variola spp.), were consistently greater in NTMRs than on fished reefs over both the short and medium term. However, there were no clear or consistent differences in the structure of fish or benthic assemblages, non-target fish density, fish species richness, or coral cover between NTMR and fished reefs. There was no indication that the displacement and concentration of fishing effort reduced coral trout populations on fished reefs. A severe tropical cyclone impacted many survey reefs during the study, causing similar declines in coral cover and fish density on both NTMR and fished reefs. However, coral trout biomass declined only on fished reefs after the cyclone. The GBRMP is performing as expected in terms of the protection of fished stocks and biodiversity for a developed country in which fishing is not excessive and targets a narrow range of species. NTMRs cannot protect coral reefs directly from acute regional-scale disturbance but, after a strong tropical cyclone, impacted NTMR reefs supported higher biomass of key fishery-targeted species and so should provide valuable sources of larvae to enhance population recovery and long-term persistence.
- Full Text
- View/download PDF
78. Probabilistic Income-Maximizing Behavior in Regional Migration: An Empirical Test
- Author
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Richard D. Evans and Robert Weinstein
- Subjects
education.field_of_study ,Actuarial science ,Internal migration ,Income risk ,Geography, Planning and Development ,Population ,Probabilistic logic ,Net migration rate ,Empirical research ,Econometrics ,Economics ,Economic model ,education ,Developed country ,Earth-Surface Processes - Abstract
This paper provides an empirical test of the hypothesis that migrants consider income risk in their evaluation of the returns to migration in that higher levels of income risk for a given region reduce the rate of net migration into that region. Theoretical approaches to the incorporation of income risk in migration models are first considered and alternative approaches are then tested using data on white and nonwhite net migration in the United States between 1960 and 1970. The results indicate support for the hypothesis that the extent of net migration is inversely affected by income risk. (EXCERPT)
- Published
- 1980
- Full Text
- View/download PDF
79. Doom and boom on a resilient reef: climate change, algal overgrowth and coral recovery
- Author
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Scarla J. Weeks, Laurence J. McCook, Sophie Dove, Richard D. Evans, David H. Williamson, George Roff, David I. Kline, Guillermo Diaz-Pulido, Ray Berkelmans, and Ove Hoegh-Guldberg
- Subjects
Ecology/Global Change Ecology ,Ecology/Community Ecology and Biodiversity ,Coral bleaching ,Coral ,Climate ,Science ,Atoll ,Biology ,Ecology/Marine and Freshwater Ecology ,Animals ,Aquaculture of coral ,Reef ,Marine and Aquatic Sciences/Ecology ,geography ,Multidisciplinary ,geography.geographical_feature_category ,Ecology ,Resilience of coral reefs ,Ecology/Plant-Environment Interactions ,Marine and Aquatic Sciences/Climate Change ,fungi ,technology, industry, and agriculture ,Eukaryota ,Coral reef ,biochemical phenomena, metabolism, and nutrition ,Anthozoa ,Marine and Aquatic Sciences/Conservation Science ,Ecology/Population Ecology ,population characteristics ,Medicine ,Environmental issues with coral reefs ,geographic locations ,Research Article - Abstract
BackgroundCoral reefs around the world are experiencing large-scale degradation, largely due to global climate change, overfishing, diseases and eutrophication. Climate change models suggest increasing frequency and severity of warming-induced coral bleaching events, with consequent increases in coral mortality and algal overgrowth. Critically, the recovery of damaged reefs will depend on the reversibility of seaweed blooms, generally considered to depend on grazing of the seaweed, and replenishment of corals by larvae that successfully recruit to damaged reefs. These processes usually take years to decades to bring a reef back to coral dominance.Methodology/principal findingsIn 2006, mass bleaching of corals on inshore reefs of the Great Barrier Reef caused high coral mortality. Here we show that this coral mortality was followed by an unprecedented bloom of a single species of unpalatable seaweed (Lobophora variegata), colonizing dead coral skeletons, but that corals on these reefs recovered dramatically, in less than a year. Unexpectedly, this rapid reversal did not involve reestablishment of corals by recruitment of coral larvae, as often assumed, but depended on several ecological mechanisms previously underestimated.Conclusions/significanceThese mechanisms of ecological recovery included rapid regeneration rates of remnant coral tissue, very high competitive ability of the corals allowing them to out-compete the seaweed, a natural seasonal decline in the particular species of dominant seaweed, and an effective marine protected area system. Our study provides a key example of the doom and boom of a highly resilient reef, and new insights into the variability and mechanisms of reef resilience under rapid climate change.
80. Some Aspects of Hypertension
- Author
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Franklin R. Nuzum and Richard D. Evans
- Subjects
General Medicine ,General Nursing - Published
- 1928
- Full Text
- View/download PDF
81. Digitise this! A quick and easy remote sensing method to monitor the daily extent of dredge plumes.
- Author
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Richard D Evans, Kathy L Murray, Stuart N Field, James A Y Moore, George Shedrawi, Barton G Huntley, Peter Fearns, Mark Broomhall, Lachlan I W McKinna, and Daniel Marrable
- Subjects
Medicine ,Science - Abstract
Technological advancements in remote sensing and GIS have improved natural resource managers' abilities to monitor large-scale disturbances. In a time where many processes are heading towards automation, this study has regressed to simple techniques to bridge a gap found in the advancement of technology. The near-daily monitoring of dredge plume extent is common practice using Moderate Resolution Imaging Spectroradiometer (MODIS) imagery and associated algorithms to predict the total suspended solids (TSS) concentration in the surface waters originating from floods and dredge plumes. Unfortunately, these methods cannot determine the difference between dredge plume and benthic features in shallow, clear water. This case study at Barrow Island, Western Australia, uses hand digitising to demonstrate the ability of human interpretation to determine this difference with a level of confidence and compares the method to contemporary TSS methods. Hand digitising was quick, cheap and required very little training of staff to complete. Results of ANOSIM R statistics show remote sensing derived TSS provided similar spatial results if they were thresholded to at least 3 mg L(-1). However, remote sensing derived TSS consistently provided false-positive readings of shallow benthic features as Plume with a threshold up to TSS of 6 mg L(-1), and began providing false-negatives (excluding actual plume) at a threshold as low as 4 mg L(-1). Semi-automated processes that estimate plume concentration and distinguish between plumes and shallow benthic features without the arbitrary nature of human interpretation would be preferred as a plume monitoring method. However, at this stage, the hand digitising method is very useful and is more accurate at determining plume boundaries over shallow benthic features and is accessible to all levels of management with basic training.
- Published
- 2012
- Full Text
- View/download PDF
82. Doom and boom on a resilient reef: climate change, algal overgrowth and coral recovery.
- Author
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Guillermo Diaz-Pulido, Laurence J McCook, Sophie Dove, Ray Berkelmans, George Roff, David I Kline, Scarla Weeks, Richard D Evans, David H Williamson, and Ove Hoegh-Guldberg
- Subjects
Medicine ,Science - Abstract
BackgroundCoral reefs around the world are experiencing large-scale degradation, largely due to global climate change, overfishing, diseases and eutrophication. Climate change models suggest increasing frequency and severity of warming-induced coral bleaching events, with consequent increases in coral mortality and algal overgrowth. Critically, the recovery of damaged reefs will depend on the reversibility of seaweed blooms, generally considered to depend on grazing of the seaweed, and replenishment of corals by larvae that successfully recruit to damaged reefs. These processes usually take years to decades to bring a reef back to coral dominance.Methodology/principal findingsIn 2006, mass bleaching of corals on inshore reefs of the Great Barrier Reef caused high coral mortality. Here we show that this coral mortality was followed by an unprecedented bloom of a single species of unpalatable seaweed (Lobophora variegata), colonizing dead coral skeletons, but that corals on these reefs recovered dramatically, in less than a year. Unexpectedly, this rapid reversal did not involve reestablishment of corals by recruitment of coral larvae, as often assumed, but depended on several ecological mechanisms previously underestimated.Conclusions/significanceThese mechanisms of ecological recovery included rapid regeneration rates of remnant coral tissue, very high competitive ability of the corals allowing them to out-compete the seaweed, a natural seasonal decline in the particular species of dominant seaweed, and an effective marine protected area system. Our study provides a key example of the doom and boom of a highly resilient reef, and new insights into the variability and mechanisms of reef resilience under rapid climate change.
- Published
- 2009
- Full Text
- View/download PDF
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