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1.
Environ Monit Assess ; 194(6): 432, 2022 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-35568770

RESUMEN

Recurrent dust storms represent a significant concern in Australia because of their related hazards and damages since particulate matter (PM) has harmful impacts on the environmental, health and economic sectors. The particulate matter may be released from natural sources and human activities. The major part of natural particulate matter is emitted into the air by wind erosion processes from desert and semi-desert areas at the world scale. A huge dust storm crossed over several areas of New South Wales (NSW), Australia, including the Sydney region on 21-22 November 2018 and decreased the horizontal visibility to less than 1 km for 22 h. This study examined the synoptic weather conditions, and assessed the air quality and identified the source and transport trajectory of the dust storm over Sydney using ground and satellite remote sensing data. PM10 (< 10 µm) concentrations were obtained from selected air quality monitoring sites operated by the Environmental Protection Agency in NSW. The highest hourly concentration of PM10 (578.7 µg/m3) was recorded at Singleton in the Hunter Valley, while concentrations in Sydney ranged from 480 to 385 µg/m3, well above the standard air quality level in Australia (50 µg/m3 per 24 h). The HYSPLIT back trajectories of air parcels suggest that the potential sources of the dust episode originated from the Lake Eyre Basin and northeast South Australia, the Mundi Mundi plains west of Broken Hill, Cobar and the grazing lands and the red sandplains in northwestern NSW. It then travelled towards the east coast. These long-range airflows transported suspended dust particles, raising air quality to hazardous levels (elevated PM10 levels) over most areas of NSW. The results from the HYSPLIT model for dust movement are confirmed by MODIS satellite images. Many areas of NSW experienced this intense dust storm due to northwest wind generated by the low-pressure systems and cold fronts over South Australia and many parts of western NSW as it moved eastward.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , Polvo/análisis , Monitoreo del Ambiente , Humanos , Material Particulado/análisis , Tecnología de Sensores Remotos
2.
PLoS One ; 14(12): e0226065, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31805134

RESUMEN

The objectives of this study were to assess gastrointestinal transit times, sedation, and signs of nausea associated with intravenous lidocaine infusions in dogs following targeted acupuncture at Pericardium-6 (PC6) and Stomach-36 (ST36). In a randomized, blind crossover design, 6 healthy, adult Beagles were fed thirty 1.5 mm barium-impregnated polyethylene spheres (BIPS), then were subject to 30 minutes of: 1) no acupuncture, 2) bilateral targeted acupuncture at PC6 and ST36, or 3) bilateral non-target acupuncture at Lung-5 (LU5) and Bladder-55 (BL55). Lidocaine was immediately administered at 1 mg/kg intravenously followed by 50 µg/kg/min. BIPS were tracked radiographically; sedation and nausea were scored at baseline (Time 0) and for 11 hours during lidocaine infusions. Transit times and sedation and nausea scores were analyzed with a linear mixed-effects model; the number of BIPS at defined time points was analyzed with a piecewise linear mixed-effects model. All P values were two-sided and P < 0.05 was considered significant. Sedation and nausea scores did not differ between treatments at any time point (all P > 0.05). However, nausea scores in all groups were significantly greater at Times 5 through 7 and at Time 11 compared to Time 0 whereas sedation scores in all groups were significantly greater at Times 2 through 11 compared to Time 0 (all P < 0.05). The number of BIPs found out of the stomach, the number found in the large intestine, gastric emptying and gastrointestinal transit times did not differ between treatments (all P > 0.05). Acupuncture at PC6 and ST36 did not alleviate nausea and sedation associated with lidocaine infusions in clinically normal animals or affect gastric emptying and gastrointestinal transit.


Asunto(s)
Puntos de Acupuntura , Terapia por Acupuntura , Sedación Consciente , Motilidad Gastrointestinal/efectos de los fármacos , Lidocaína/administración & dosificación , Lidocaína/efectos adversos , Náusea/inducido químicamente , Animales , Perros , Femenino , Vaciamiento Gástrico/efectos de los fármacos , Infusiones Intravenosas , Masculino , Náusea/diagnóstico por imagen , Náusea/prevención & control , Radiografía
3.
PLoS One ; 14(7): e0218430, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31314758

RESUMEN

Reconstructing past sea levels can help constrain uncertainties surrounding the rate of change, magnitude, and impacts of the projected increase through the 21st century. Of significance is the mid-Holocene relative sea-level highstand in tectonically stable and remote (far-field) locations from major ice sheets. The east coast of Australia provides an excellent arena in which to investigate changes in relative sea level during the Holocene. Considerable debate surrounds both the peak level and timing of the east coast highstand. The southeast Australian site of Bulli Beach provides the earliest evidence for the establishment of a highstand in the Southern Hemisphere, although questions have been raised about the pretreatment and type of material that was radiocarbon dated for the development of the regional sea-level curve. Here we undertake a detailed morpho- and chronostratigraphic study at Bulli Beach to better constrain the timing of the Holocene highstand in eastern Australia. In contrast to wood and charcoal samples that may provide anomalously old ages, probably due to inbuilt age, we find that short-lived terrestrial plant macrofossils provide a robust chronological framework. Bayesian modelling of the ages provide improved dating of the earliest evidence for a highstand at 6,880±50 cal BP, approximately a millennium later than previously reported. Our results from Bulli now closely align with other sea-level reconstructions along the east coast of Australia, and provide evidence for a synchronous relative sea-level highstand that extends from the Gulf of Carpentaria to Tasmania. Our refined age appears to be coincident with major ice mass loss from Northern Hemisphere and Antarctic ice sheets, supporting previous studies that suggest these may have played a role in the relative sea-level highstand. Further work is now needed to investigate the environmental impacts of regional sea levels, and refine the timing of the subsequent sea-level fall in the Holocene and its influence on coastal evolution.


Asunto(s)
Fósiles , Cubierta de Hielo , Elevación del Nivel del Mar/historia , Regiones Antárticas , Australia , Isótopos de Carbono/análisis , Historia Antigua
5.
Environ Monit Assess ; 190(7): 375, 2018 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-29862438

RESUMEN

Monitoring estuarine ecological-geomorphological dynamics has become a crucial aspect of studying the impacts of climate change and worldwide infrastructure development in coastal zones. Together, these factors have changed the natural eco-geomorphic processes that affect estuarine regimes and comprehensive modelling of coastal resources can assist managers to make appropriate decisions about their sustainable use. This study has utilised Towamba estuary (southeastern NSW, Australia), to demonstrate the value and priority of modelling estuarine dynamism as a measure of the rates and consequences of eco-geomorphic changes. This research employs several geoinformatic modelling approaches over time to investigate and assess how climate change and human activities have altered this estuarine eco-geomorphic setting. Multitemporal trend/change analysis of sediment delivery, shoreline positions and land cover, determined from fieldwork and GIS analysis of remote sensing datasets, shows significant spatio-temporal changes to the elevation and areal extent of sedimentary facies in the Towamba estuary over the past 65 years. Geomorphic growth (~ 2600 m2 annually) has stabilised the estuarine habitats, particularly within native vegetation, salt marsh and mangrove areas. Geomorphic changes have occurred because of a combination of sediment runoff from the mostly unmodified terrestrial catchment, nearshore processes (ocean dynamics) and human activities. The construction of GIS models, verified with water and sediment samples, can characterise physical processes and quantify changes within the estuarine ecosystem. Such robust models will allow resource managers to evaluate the potential effects of changes to the current coastal ecosystems.


Asunto(s)
Monitoreo del Ambiente/métodos , Estuarios , Sistemas de Información Geográfica , Cambio Climático , Conservación de los Recursos Naturales , Ecosistema , Actividades Humanas , Humanos , Nueva Gales del Sur , Análisis Espacio-Temporal , Humedales
6.
PLoS One ; 13(4): e0193025, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29641524

RESUMEN

This paper presents a reassessment of the archaeological record at Leang Burung 2, a key early human occupation site in the Late Pleistocene of Southeast Asia. Excavated originally by Ian Glover in 1975, this limestone rock-shelter in the Maros karsts of Sulawesi, Indonesia, has long held significance in our understanding of early human dispersals into 'Wallacea', the vast zone of oceanic islands between continental Asia and Australia. We present new stratigraphic information and dating evidence from Leang Burung 2 collected during the course of our excavations at this site in 2007 and 2011-13. Our findings suggest that the classic Late Pleistocene modern human occupation sequence identified previously at Leang Burung 2, and proposed to span around 31,000 to 19,000 conventional 14C years BP (~35-24 ka cal BP), may actually represent an amalgam of reworked archaeological materials. Sources for cultural materials of mixed ages comprise breccias from the rear wall of the rock-shelter-remnants of older, eroded deposits dated to 35-23 ka cal BP-and cultural remains of early Holocene antiquity. Below the upper levels affected by the mass loss of Late Pleistocene deposits, our deep-trench excavations uncovered evidence for an earlier hominin presence at the site. These findings include fossils of now-extinct proboscideans and other 'megafauna' in stratified context, as well as a cobble-based stone artifact technology comparable to that produced by late Middle Pleistocene hominins elsewhere on Sulawesi.


Asunto(s)
Arqueología , Fósiles , Tecnología , Animales , Hominidae , Humanos , Indonesia , Islas
7.
Am J Vet Res ; 78(5): 550-557, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28441056

RESUMEN

OBJECTIVE To quantify nausea and sedation scores, gastric emptying time, and gastrointestinal transit time after IV administration of a lidocaine hydrochloride bolus followed by a constant rate infusion (CRI) in clinically normal dogs. ANIMALS 6 Beagles. PROCEDURES In a crossover study, dogs were fed thirty 1.5-mm barium-impregnated spheres (BIPS) and received a saline (0.9% NaCl) solution bolus (0.05 mL/kg) IV (time 0) followed by a CRI at 10 mL/h, a lidocaine bolus (1 mg/kg) IV followed by a CRI at 25 µg/kg/min, or a lidocaine bolus (1 mg/kg) IV followed by a CRI at 50 µg/kg/min; CRIs were for 12 hours. Nausea and sedation scores were assessed and abdominal radiographs obtained immediately after feeding of BIPS and every hour for 12 hours and again 16 hours after CRI start. Percentage of BIPSs in the small and large intestines, gastric emptying time, and gastrointestinal transit time were assessed. RESULTS Gastric emptying time did not differ significantly among treatments. Significantly more BIPS were in the large intestine 4 to 7 hours after treatment start for the 50-µg/kg/min treatment than for the other 2 treatments. Six hours after treatment start, significantly more BIPS were in the large intestine for the 25-µg/kg/min treatment than for the saline solution treatment. Higher sedation and nausea scores were associated with the 50-µg/kg/min CRI. CONCLUSIONS AND CLINICAL RELEVANCE In clinically normal dogs, lidocaine CRI did not significantly affect gastric emptying. However, gastrointestinal transit time was mildly decreased and sedation and nausea scores increased in dogs administered a lidocaine CRI at clinically used doses.


Asunto(s)
Lidocaína/farmacología , Animales , Estudios Cruzados , Perros , Femenino , Vaciamiento Gástrico/efectos de los fármacos , Tránsito Gastrointestinal/efectos de los fármacos , Infusiones Intravenosas , Lidocaína/administración & dosificación , Lidocaína/efectos adversos , Lidocaína/metabolismo , Masculino , Náusea/inducido químicamente , Método Simple Ciego
8.
Am J Vet Res ; 78(4): 458-464, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28346006

RESUMEN

OBJECTIVE To characterize and compare MRI susceptibility artifacts related to titanium and stainless steel monocortical screws in the cervical vertebrae and spinal cord of canine cadavers. SAMPLE 12 canine cadavers. PROCEDURES Cervical vertebrae (C4 and C5) were surgically stabilized with titanium or stainless steel monocortical screws and polymethylmethacrylate. Routine T1-weighted, T2-weighted, and short tau inversion recovery sequences were performed at 3.0 T. Magnetic susceptibility artifacts in 20 regions of interest (ROIs) across 4 contiguous vertebrae (C3 through C6) were scored by use of an established scoring system. RESULTS Artifact scores for stainless steel screws were significantly greater than scores for titanium screws at 18 of 20 ROIs. Artifact scores for titanium screws were significantly higher for spinal cord ROIs within the implanted vertebrae. Artifact scores for stainless steel screws at C3 were significantly less than at the other 3 cervical vertebrae. CONCLUSIONS AND CLINICAL RELEVANCE Evaluation of routine MRI sequences obtained at 3.0 T revealed that susceptibility artifacts related to titanium monocortical screws were considered mild and should not hinder the overall clinical assessment of the cervical vertebrae and spinal cord. However, mild focal artifacts may obscure small portions of the spinal cord or intervertebral discs immediately adjacent to titanium screws. Severe artifacts related to stainless steel screws were more likely to result in routine MRI sequences being nondiagnostic; however, artifacts may be mitigated by implant positioning.


Asunto(s)
Tornillos Óseos/veterinaria , Vértebras Cervicales/diagnóstico por imagen , Perros , Imagen por Resonancia Magnética/veterinaria , Polimetil Metacrilato , Médula Espinal/diagnóstico por imagen , Animales , Artefactos , Cadáver , Vértebras Cervicales/patología , Imagen por Resonancia Magnética/métodos , Acero Inoxidable , Titanio
9.
Arch Environ Contam Toxicol ; 72(2): 247-259, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27990606

RESUMEN

Measurement of elevated trace elements is an important component of environmental assessment and management of estuarine marine sediments in systems adjacent to concentrated human activity. The present study surveys the estuarine sediments in selected tributary bays, creeks, and the upper segments of the Georges River system, NSW, Australia, which flows into the Tasman Sea through Botany Bay. A total of 146 surface sediment samples were analysed by X-ray fluorescence. Potential pollution of sediments was evaluated using potential load index, modified degree of contamination, and potential ecological risk index. The spatial distribution of trace elements varies between sites. Variable sources of contamination, including runoff from catchment areas, and emissions from watercraft and boatyards are contributing sources. Bay morphologies and their interactions with catchment and tidal flows play significant roles in the distribution of trace elements. The greatest concentration of trace elements occurs around discharge points and in the inner parts of bays that have high percentages of mud particles and organic matter. The lowest contamination by trace elements was found in sandy sediments along the shoreline and edges of the bays. Trace element distributions decline in concentration in residential-free areas and reach background levels in deeper sediment cores. The concentrations of trace elements were controlled by discharge points from the catchment area, marine boat activities, bay morphology, and sediment types (sand, silt, and clay). The highest pollutant concentrations are the result of past legal, but uncontrolled, discharge of waste from manufacturing into Salt Pan Creek.


Asunto(s)
Sedimentos Geológicos/análisis , Oligoelementos/análisis , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente , Humanos , Nueva Gales del Sur , Medición de Riesgo , Ríos/química
10.
Environ Monit Assess ; 187(2): 20, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25626565

RESUMEN

The distribution of trace metals (spatial and temporal) and sedimentary fractions were investigated to identify the concentrations and sources of trace metals within Kogarah Bay, NSW, Australia. A total of 59 surface sediments and six subsurface samples from core of the sediment were collected. The contamination factor and pollution load index indices used to evaluate environmental effects of trace metals. The study area was found to be uncontaminated with Cr and Ni, moderately contaminated with As and considerably contaminated with Cu, Zn and Pb. The concentrations of Cr and Ni were below both effect range low and effect range median, while As, Cu, Zn and Pb were slightly above effect range low. The highest concentrations of these trace metals such as Cu, Zn and Pb were found in the north, northwest and southeast of the bay, close to discharge points, stormwater outlets and around boatyards and watercrafts. The spatial distributions of metals were strongly related to muddy particles and organic matter. The temporal sediments of metals declined with increased sediment depth, which reflects accumulation of trace metals since European settlement in this area. Furthermore, the source of the trace metals was found to be stormwater outlets, gasoline fumes, boatyards and other human activities.


Asunto(s)
Bahías/química , Monitoreo del Ambiente , Sedimentos Geológicos/química , Metales/análisis , Contaminantes Químicos del Agua/análisis , Nueva Gales del Sur
11.
Bull Environ Contam Toxicol ; 94(1): 52-7, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25432296

RESUMEN

The disposal of untreated urban and industrial wastewater has a deleterious effect on both the water and sediment quality of Oyster Bay located in south Sydney, Australia. The present investigation was undertaken to evaluate the potential pollution of marine sediments in Oyster Bay. The results of metals were compared with adverse biological effect values effect range low (ERL) and effect range median (ERM). Spatial distribution of trace metals was estimated by applying geographic information system. The results indicated that the sediments were polluted with Cu, Zn, As and Pb, which exceeded ERL levels. However, these metals were still below ERM values, and other metals Cr and Ni were below ERL. Moreover, the highest concentrations of metals were around discharge points and in the inner bay. Further, trace metals could be attributed to human activities within the bay as they declined in concentrations with increasing sediment depth.


Asunto(s)
Sedimentos Geológicos/química , Metales Pesados/análisis , Contaminantes Químicos del Agua/análisis , Animales , Australia , Bahías , Monitoreo del Ambiente , Contaminación Ambiental/análisis , Metales/análisis , Metales Pesados/química , Oligoelementos , Contaminantes Químicos del Agua/química
12.
Vet Radiol Ultrasound ; 53(5): 486-91, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22818244

RESUMEN

Tracheobronchial lymphadenomegaly is commonly associated with lymphosarcoma and disseminated mycotic infection. Available data also suggest other pathologic causes of enlarged tracheobronchial lymph nodes. Our objective was to establish the distribution and prevalence of diseases that cause radiographically evident tracheobronchial lymphadenomegaly in a large population of dogs. Patients were divided into groups based on the methods of diagnoses with 25 having confirmed diagnoses and 85 with presumptive diagnoses. Of the 110 dogs in the study, 92 (84%) had neoplasia and 18 (16%) had infectious diseases. Infections were attributed to Coccidioides (12, 67%), Aspergillus (3, 17%), and 1 each (6%) to Nocardia, Penicillium, and Mycobacteriosis. Tumors were characterized as lymphoma (66, 60%) or nonlymphoid (26, 23.6%). Nonlymphomas in Group 1 included histiocytic sarcoma complex (16%), carcinoma (12%), adenocarcinoma (8%), osteosarcoma (8%), chemodectoma (4%), ganglioneuroblastoma (4%), and neuroendocrine (4%). The number of dogs with tracheobronchial lymphadenomegaly scores 1, 2, 3, 4, or 5 (with 5 being the greatest) was 8 (7%), 15 (14%), 30 (27%), 15 (14%), and 44 (38%), respectively. The results suggest that in addition to diagnoses of lymphoma and fungal infections, other neoplasms and in particular histiocytic sarcoma and metastatic adenocarcinoma, should be considered when tracheobronchial lymphadenomegaly is identified radiographically in dogs. When comparing the degree of tracheobronchial lymphadenopathy by disease category, there was no significant affiliation (P = 0.33).


Asunto(s)
Enfermedades de los Perros/diagnóstico por imagen , Enfermedades Linfáticas/veterinaria , Neoplasias/veterinaria , Radiografía Torácica/veterinaria , Animales , Bronquios , Enfermedades de los Perros/diagnóstico , Perros , Ganglios Linfáticos/diagnóstico por imagen , Enfermedades Linfáticas/complicaciones , Enfermedades Linfáticas/diagnóstico por imagen , Linfoma/complicaciones , Linfoma/diagnóstico por imagen , Linfoma/veterinaria , Infecciones por Mycobacterium/complicaciones , Infecciones por Mycobacterium/diagnóstico , Infecciones por Mycobacterium/diagnóstico por imagen , Infecciones por Mycobacterium/veterinaria , Micosis/complicaciones , Micosis/diagnóstico , Micosis/diagnóstico por imagen , Micosis/veterinaria , Neoplasias/complicaciones , Neoplasias/diagnóstico , Neoplasias/diagnóstico por imagen , Tráquea
13.
J Environ Radioact ; 99(7): 1111-20, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18289748

RESUMEN

Environmental radionuclides can be employed as tracers of sediment movement and delivery to water bodies such as lakes and reservoirs. The chronologies of sediments that have accumulated in the Cordeaux reservoir in Sydney, Australia, were determined by the rate of change of (210)Pb(ex) with depth and indicate slow accretion in the reservoir. The ratio of enrichment of radionuclides in sediment cores to (210)Pb(ex) and (137)Cs concentrations in a reference soil sample within the Cordeaux catchment indicates that the dominant source of sediment in the Cordeaux reservoir is surface erosion (detachment and removal of sediment at depths less than 30 cm). However, in the Kembla Creek arm of the reservoir a mixture of sources was detected and includes sheet and rill erosion together with sub-soil contributions. Implications for the utility of these radionuclide sedimentation assessments, especially where samples are limited, are that well-constrained chronologies and sources of soil erosion are facilitated.


Asunto(s)
Monitoreo del Ambiente/métodos , Sedimentos Geológicos/análisis , Contaminantes Radiactivos del Agua/análisis , Australia , Radioisótopos de Cesio/análisis , Geografía , Radioisótopos de Plomo/análisis , Ríos
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