RESUMO
Understanding the age distribution of groundwater can provide information on both the recharge history as well as the geochemical evolution of groundwater flow systems. Of the few candidates available that can be used to date old groundwater, 81Kr shows the most promise because its input function is constant through time and there are less sources and sinks to complicate the dating procedure in comparison to traditional tracers such as 36Cl and 4He. In this paper we use 81Kr in a large groundwater basin to obtain a better understanding of the residence time distribution of an unconfined-confined aquifer system. A suite of environmental tracers along a groundwater flow path in the south-west Great Artesian Basin of Australia have been sampled. All age tracers (85Kr, 39Ar 14C, 81Kr, 36Cl and 4He) display a consistent increase in groundwater age with distance from the recharge area indicating the presence of a connected flow path. Assuming that 81Kr is the most accurate dating technique the 36Cl/Cl systematics was unravelled to reveal information on recharge mechanism and chloride concentration at the time of recharge. Current-day recharge occurs via ephemeral river recharge beneath the Finke River, while diffuse recharge is minor in the young groundwaters. Towards the end of the transect the influence of ephemeral recharge is less while diffuse recharge and the initial chloride concentration at recharge were higher.
Assuntos
Cloretos , Água Subterrânea , Rios , Radioisótopos , Monitoramento Ambiental/métodosRESUMO
While metal nanoparticles are being increasingly used in many sectors of the economy, there is growing interest in the biological and environmental safety of their production. The main methods for nanoparticle production are chemical and physical approaches that are often costly and potentially harmful to the environment. The present review is devoted to the possibility of metal nanoparticle synthesis using plant extracts. This approach has been actively pursued in recent years as an alternative, efficient, inexpensive, and environmentally safe method for producing nanoparticles with specified properties. This review provides a detailed analysis of the various factors affecting the morphology, size, and yield of metal nanoparticles. The main focus is on the role of the natural plant biomolecules involved in the bioreduction of metal salts during the nanoparticle synthesis. Examples of effective use of exogenous biomatrices (peptides, proteins, and viral particles) to obtain nanoparticles in plant extracts are discussed.
RESUMO
Continuous (hourly) measurements of dissolved oxygen and chlorophyll (determined by fluorimetry) were made for an inter-linked lowland river and canal system. The dissolved oxygen data were used to estimate daily rates of re-aeration, photosynthesis and respiration, using a process-based analytical technique (the Delta method). In-situ fluorimeter measurements of chlorophyll were ground-truthed on a fortnightly basis using laboratory methanol extraction of chlorophyll and spectrophotometric analysis. Water samples were also analysed for algal species on a fortnightly basis. The river and canal exhibited very similar rates of photosynthesis and respiration during the summer of 2001, despite much higher chlorophyll concentrations and total algal counts, indicating that benthic algae and/or aquatic macrophytes may be making an important contribution to photosynthesis rates in the river. Suspended algal populations in the canal are dominated by planktonic species, whereas the river has a higher proportion of species which are predominantly benthic in habitat. The river exhibited higher rates of respiration, reflecting a higher organic loading from external (e.g. sewage effluent) sources.
Assuntos
Clorofila/análise , Monitoramento Ambiental/métodos , Oxigênio/análise , Eucariotos , Fluorometria , Fotossíntese , Plâncton , Dinâmica Populacional , Rios , Esgotos , SolubilidadeRESUMO
Toronto's SATP (Sexual Abuse Treatment Project), the first sexual abuse treatment program in a child welfare setting in Canada, provides comprehensive treatment resources for sexually abused children, their families, and offenders. The authors include a description of the program's major components, as well as an evaluation of SATP's first eighteen months.
Assuntos
Abuso Sexual na Infância/prevenção & controle , Proteção da Criança , Psicoterapia/métodos , Criança , Abuso Sexual na Infância/psicologia , Aconselhamento , Terapia Familiar , Humanos , Psicoterapia de GrupoRESUMO
The respiratory effects of intravenous indoprofen 400 mg, a highly effective non-steroidal anti-inflammatory analgesic, were compared with those of morphine 10 mg in 10 healthy volunteers. Morphine exhibited its characteristic adverse respiratory depressant properties, Indoprofen, in contrast, did not influence the subjects' breathing pattern.
Assuntos
Indoprofen/farmacologia , Morfina/farmacologia , Fenilpropionatos/farmacologia , Respiração/efeitos dos fármacos , Adolescente , Adulto , Dióxido de Carbono/fisiologia , Feminino , Humanos , Injeções Intravenosas , Medidas de Volume Pulmonar , Masculino , Pressão Parcial , Distribuição Aleatória , Volume de Ventilação Pulmonar , Fatores de TempoRESUMO
Indoprofen (400 mg), a non-opioid, non-steroidal anti-inflammatory drug, was compared on a random, double-blind basis with pethidine (1,5 mg/kg) after elective caesarean section (40 patients) and after orthopaedic surgery (40 patients). The drugs were given intravenously during anaesthesia and provided adequate analgesia for a period of up to 2 hours postoperatively. No significant differences between the two drugs were noted in terms of efficacy and side-effects.