999 resultados para Sculptors -- West (U.S.)
Resumo:
Koala (Phascolarctos cinereus) populations in eastern Australia are threatened by land clearing for agricultural and urban development. At the same time, conservation efforts are hindered by a dearth of information about inland populations. Faecal deposits offer a source of information that is readily available and easily collected non-invasively. We detail a faecal pellet sampling protocol that was developed for use in a large rangeland biogeographic region. The method samples trees in belt transects, uses a thorough search at the tree base to quickly identify trees with koala pellets under them, then estimates the abundance of faecal pellets under those trees using 1-m(2) quadrats. There was a strong linear relationship between these estimates and a complete enumeration of pellet abundance under the same trees. We evaluated the accuracy of our method in detecting trees where pellets were present by means of a misclassification index that was weighed more heavily for missed trees that had high numbers of pellets under them. This showed acceptable accuracy in all landforms except riverine, where some trees with large numbers of pellets were missed. Here, accuracy in detecting pellet presence was improved by sampling with quadrats, rather than basal searches. Finally, we developed a method to reliably age pellets and demonstrate how this protocol could be used with the faecal-standing-crop method to derive a regional estimate of absolute koala abundance.
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We detail the automatic construction of R matrices corresponding to (the tensor products of) the (O-m\alpha(n)) families of highest-weight representations of the quantum superalgebras Uq[gl(m\n)]. These representations are irreducible, contain a free complex parameter a, and are 2(mn)-dimensional. Our R matrices are actually (sparse) rank 4 tensors, containing a total of 2(4mn) components, each of which is in general an algebraic expression in the two complex variables q and a. Although the constructions are straightforward, we describe them in full here, to fill a perceived gap in the literature. As the algorithms are generally impracticable for manual calculation, we have implemented the entire process in MATHEMATICA; illustrating our results with U-q [gl(3\1)]. (C) 2002 Published by Elsevier Science B.V.
Resumo:
Measurements are given for all and full descriptions and illustrations for some of the following enenterid species: Enenterum aureum Linton, 1910 in Kyphosus bigibbus and K. sydneyanus? from Ningaloo Coral Reef, Western Australia, K. vaigiensis from off Heron Island, Queensland and K. vaigiensis from off Moorea, French Polynesia; E. mannarense Hafeezullah, 1980 in K. bigibbus and K. sydneyanus? from Ningaloo Coral Reef; E. elongatum Yamaguti, 1970 in K. vaigiensis from Heron Island, Queensland and K. bigibbus and K. sydneyanus? from Ningaloo Coral Reef; Koseiria alanwilliamsi sp. nov. in Kyphosus cornelii from off Kalbarri, Western Australia; Koseiria xishaense Gu et Shen, 1983 in K. vaigiensis from off Heron Island and K. bigibbus from off Palau, Micronesia; Proenenterum isocotylum Manter, 1954 in Aplodactylus arctidens from off Stanley, Tasmania; R ericotylum Manter, 1954 in A. arctidens from off Stanley; Cadenatella isuzumi Machida, 1993 from Kyphosus bigibbus and K. sydneyanus? from Ningaloo Coral Reef; Cadenatella pacifica (Yamaguti, 1970) from Kyphosus bigibbus from Ningaloo Coral Reef. Two recent cladistic studies of the Enenteridae are discussed and a further analysis has shown that Enenterum and Cadenatella are monophyletic, whilst Koseiria appears polyphyletic. The zoogeography and host-specificity of Kyphosus-inhabiting enenterids is discussed.
Resumo:
An antigen capture immunoassay to detect West Nile (WN) virus antigen in infected mosquitoes and avian tissues has been developed. With this assay purified WN virus was detected at a concentration of 32 pg/0.1 ml, and antigen in infected suckling mouse brain and laboratory-infected mosquito pools could be detected when the WN virus titer was 10(2.1) to 10(3.7) PFU/0.1 ml. In a blindly coded set of field-collected mosquito pools (n = 100), this assay detected WN virus antigen in 12 of 18 (66.7%) TaqMan-positive pools, whereas traditional reverse transcriptase PCR detected 10 of 18 (55.5%) positive pools. A sample set of 73 organ homogenates from naturally infected American crows was also examined by WN virus antigen capture immunoassay and TaqMan for the presence of WN virus. The antigen capture assay detected antigen in 30 of 34 (88.2%) TaqMan-positive tissues. Based upon a TaqMan-generated standard curve of infectious WN virus, the limit of detection in the antigen capture assay for avian tissue homogenates was approximately 10(3) PFU/0.1 ml. The recommended WN virus antigen capture protocol, which includes a capture assay followed by a confirmatory inhibition assay used to retest presumptive positive samples, could distinguish between the closely related WN and St. Louis encephalitis viruses in virus-infected mosquito pools and avian tissues. Therefore, this immunoassay demonstrates adequate sensitivity and specificity for surveillance of WN virus activity in mosquito vectors and avian hosts, and, in addition, it is easy to perform and relatively inexpensive compared with the TaqMan assay.
Resumo:
We present whole-rock and zircon rare earth element (REE) data from two early Archaean gneisses (3.81 Ga and 3.64 Ga) from the Itsaq gneiss complex, south-west Greenland. Both gneisses represent extremely rare examples of unaltered, fresh and relatively undeformed igneous rocks of such antiquity. Cathodoluminescence imaging of their zircons indicates a single crystallisation episode with no evidence for either later metamorphic and/or anatectic reworking or inheritance of earlier grains. Uniform, single-population U/Pb age data confirm the structural simplicity of these zircons. One sample, a 3.64 Ga granodioritic gneiss from the Gothabsfjord, yields a chondrite-normalised REE pattern with a positive slope from La to Lu as well as substantial positive Ce and slight negative Eu anomalies, features generally considered to be typical of igneous zircon. In contrast, the second sample, a 3.81 Ga tonalite from south of the Isua Greenstone Belt, has variable but generally much higher light REE abundances, with similar middle to heavy REE. Calculation of zircon/melt distribution coefficients (D-REE(zircon/melt)) from each sample yields markedly different values for the trivalent REE (i.e. Ce and Eu omitted) and simple application of one set of D-REE(zircon/melt) to model the melt composition for the other sample yields concentrations that are in error by up to two orders of magnitude for the light REE (La-Nd). The observed light REE overabundance in the 3.81 Ga tonalite is a commonly observed feature in terrestrial zircons for which a number of explanations ranging from lattice strain to disequilibrium crystallisation have been proposed and are further investigated herein. Regardless of the cause of light REE overabundance, our study shows that simple application of zircon/melt distribution coefficients is not an unambiguous method for ascertaining original melt composition. In this context, recent studies that use REE data to claim that > 4.3 Ga Hadean detrital zircons originally crystallised from an evolved magma, in turn suggesting the operation of geological processes in the early Earth analogous to those of the present day (e.g. subduction and melting of hydrated oceanic crust), must be regarded with caution. Indeed, comparison of terrestrial Hadean and > 3.9 Ga lunar highland zircons shows remarkable similarities in the light REE, even though subduction processes that have been used to explain the terrestrial zircons have never operated on the Moon. (C) 2002 Elsevier Science B.V. All rights reserved.
Resumo:
It has been established that modern humans were living in the Levant and Africa ca. 100 ka ago. Hitherto, this has contrasted with the situation in China where no unequivocal specimens of this species have been securely dated to more than 30 ka. Here we present the results of stratigraphic studies and U-series dating of the Tongtianyan Cave, the discovery site of the Liujiang hominid, which represents one of the few well-preserved fossils of modern Homo sapiens in China. The human fossils are inferred to come from either a refilling breccia or a primarily deposited gravel-bearing sandy clay layer. In the former case, which is better supported, the fossils would date to at least similar to 68 ka, but more likely to similar to 111-139 ka. Alternatively, they would be older than, similar to 153 ka. Both scenarios would make the Liujiang hominid one of the earliest modem humans in East Asia, possibly contemporaneous with the earliest known representatives from the Levant and Africa. Parallel studies on other Chinese localities have provided supporting evidence for the redating of Liujiang, which may have important implications for, the origin of modem humans. (C) 2002 Elsevier Science Ltd. All rights reserved.
Resumo:
Ethnographic data collected over a 5-year period is analyzed to determine how the Personal Responsibility & Work Opportunity Reconciliation Act of 1996 (PRWORA) has affected the lives of young male drug dealers from AIDS-afflicted families residing in Detroit. The data analysis indicated that the participants perceived drug dealing as the only viable employment opportunity for meeting the quotidian & health care needs of their families. The findings also revealed that the participants were highly aware of local political processes & the necessities of caring for relatives living with AIDS. Additional attention is dedicated to exploring the state of MI's rationale for ending the General Assistance Program, the sociocultural foundations of the PRWORA, various stipulations of the PRWORA, & how the PRWORA has augmented the legal vulnerability of welfare recipients. It is concluded that the PRWORA will force many welfare recipients to engage in illicit activities & will generally decrease recipients' health. 59 References. J. W. Parker
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A grey snapper (Lutjanus griseus), a grouper (Serranidae) and a blackjack (Caranx lugubris) were implicated in three different ciguatera poisonings in Guadeloupe, French West Indies. A mouse bioassay indicated toxicity for each specimens: 0.5-1, greater than or equal to 1 and > 1 M Ug g(-1), respectively. After purification by gel filtration chromatography, the samples were analysed by high-performance liquid chromatography coupled to mass spectrometry (LC-MS). The toxin profiles differ from one fish to another. C-CTX-1 was detected at 0.24, 0.90 and 13.8 ng g(-1) flesh in the snapper, grouper and jack, respectively. It contributed only to part of the whole toxicity determined by the mouse bioassay. Other toxins identified were C-CTX-2 (a C-CTX-1 epimer), three additional isomers of C-CTX-1 or -2, and five ciguatoxin congeners (C-CTX-1127, C-CTX-1143 and its isomer C-CTX-1143a, and C-CTX-1157 and its isomer C-CTX-1157b). Putative hydroxy-polyether-like compounds were also detected in the flesh of the grouper with [M+ + H](+) ions at m/z 851.51, 857.50, 875.51, 875.49 and 895.54 Da. Some of these compounds have the same mass range as some known dinoflagellate toxins. In conclusion, this study confirms the usefulness of LC-MS analysis to determine the ciguatoxins levels and the toxin profile in fish flesh hazardous to humans.
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We present and prove in detail a Poincare-Birkhoff-Witt commutator lemma for the quantum superalgebra U-q[gl(m\n)]. (C) 2003 American Institute of Physics.
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To date there have been few quantitative studies of the distribution of, and relative habitat utilisation by, koalas in the mulgalands of Queensland. To examine these parameters we applied habitat-accessibility and relative habitat-utilisation indices to estimates of faecal pellet density sampled at 149 sites across the region. Modelling the presence of pellets using logistic regression showed that the potential range of accessible habitats and relative habitat use varied greatly across the region, with rainfall being probably the most important determinant of distribution. Within that distribution, landform and rainfall were both important factors affecting habitat preference. Modelling revealed vastly different probabilities of finding a pellet under trees depending on the tree species, canopy size, and location within the region.
Resumo:
This study used faecal pellets to investigate the broadscale distribution and diet of koalas in the mulgalands biogeographic region of south-west Queensland. Koala distribution was determined by conducting faecal pellet searches within a 30-cm radius of the base of eucalypts on 149 belt transects, located using a multi-scaled stratified sampling design. Cuticular analysis of pellets collected from 22 of these sites was conducted to identify the dietary composition of koalas within the region. Our data suggest that koala distribution is concentrated in the northern and more easterly regions of the study area, and appears to be strongly linked with annual rainfall. Over 50% of our koala records were obtained from non-riverine communities, indicating that koalas in the study area are not primarily restricted to riverine communities, as has frequently been suggested. Cuticular analysis indicates that more than 90% of koala diet within the region consists of five eucalypt species. Our data highlights the importance of residual Tertiary landforms to koala conservation in the region.
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Measuring perceptions of customers can be a major problem for marketers of tourism and travel services. Much of the problem is to determine which attributes carry most weight in the purchasing decision. Older travellers weigh many travel features before making their travel decisions. This paper presents a descriptive analysis of neural network methodology and provides a research technique that assesses the weighting of different attributes and uses an unsupervised neural network model to describe a consumer-product relationship. The development of this rich class of models was inspired by the neural architecture of the human brain. These models mathematically emulate the neurophysical structure and decision making of the human brain, and, from a statistical perspective, are closely related to generalised linear models. Artificial neural networks or neural networks are, however, nonlinear and do not require the same restrictive assumptions about the relationship between the independent variables and dependent variables. Using neural networks is one way to determine what trade-offs older travellers make as they decide their travel plans. The sample of this study is from a syndicated data source of 200 valid cases from Western Australia. From senior groups, active learner, relaxed family body, careful participants and elementary vacation were identified and discussed. (C) 2003 Published by Elsevier Science Ltd.
Resumo:
Fifteen years ago it was proposed that the conversion of kangaroos from a pest to an economically valuable resource would allow graziers to reduce the numbers of domestic stock and thereby lower total grazing pressure. Since then, little progress towards this goal has been achieved. This is believed to be due mainly to the low prices obtained for kangaroo products. A survey of graziers in south-west Queensland was carried out to discover their opinions on kangaroos as a potential economic resource. Questions on the harvesting of feral goats were also included in the survey because of the contrast this industry provides to kangaroo harvesting in terms of grazier involvement. The results of the survey are discussed in relation to resource ownership rights; kangaroo product prices and marketing; and competition within the kangaroo harvesting industry. They show that while low kangaroo product prices do act as a disincentive to graziers, other administrative, legal and institutional factors are also important impediments to their entry to the industry. It is concluded that until the focus of attention widens to include consideration of these as well as just market factors, little progress will be made towards integrating graziers into the kangaroo harvesting industry.
Resumo:
The movements of the ricefield rats (Rattus argentiventer) near a trap-barrier system (TBS) were assessed in lowland flood-irrigated rice crops in West Java, Indonesia, to test the hypothesis that a TBS with a 'trap-crop' modifies the movements of rats within 200 m from the trap-crop. The home range use and locations of rat burrows were assessed using radiotelemetry at two sites, one with a TBS with trap-crop (Treatment site, the crop inside the fence was planted 3 weeks earlier than the surrounding crop) and the other with a TBS without trap-crop (Control site, the crop inside the fence was planted at the same time as the surrounding crop). Each TBS was a 50 x 50 m plastic fence with eight multiple-capture rat traps set at the base. More than 700 rats were caught in the TBS with trap-crop, whereas only 10 rats were caught in the TBS without trap-crop. The home range size of females was significantly smaller at the Treatment site (0.96 ha) than the Control site (2.99 ha), but there was no difference for males. Seventy-eight per cent of rats caught in the TBS and fitted with radiocollars had their daytime burrow locations within 200 m of the TBS. We could not determine if the rats caught in the TBS were residents or transients according to demographic parameters. Our results support the hypothesis that a TBS with a trap-crop protects the surrounding rice crop out to a distance of at least 200 m.
Resumo:
A plasmid DNA directing transcription of the infectious full-length RNA genome of Kunjin (KUN) virus in vivo from a mammalian expression promoter was used to vaccinate mice intramuscularly. The KUN viral cDNA encoded in the plasmid contained the mutation in the NS1 protein (Pro-250 to Leu) previously shown to attenuate KUN virus in weanling mice. KUN virus was isolated from the blood of immunized mice 3-4 days after DNA inoculation, demonstrating that infectious RNA was being transcribed in vivo; however, no symptoms of virus-induced disease were observed. By 19 days postimmunization, neutralizing antibody was detected in the serum of immunized animals. On challenge with lethal doses of the virulent New York strain of West Nile (WN) or wild-type KUN virus intracerebrally or intraperitoneally, mice immunized with as little as 0.1-1 mug of KUN plasmid DNA were solidly protected against disease. This finding correlated with neutralization data in vitro showing that serum from KUN DNA-immunized mice neutralized KUN and WN,viruses with similar efficiencies. The results demonstrate that delivery of an attenuated but replicating KUN virus via a plasmid DNA vector may provide an effective vaccination strategy against virulent strains of WN virus.