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1.
J Environ Manage ; 295: 113067, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34171782

RESUMO

There is a growing need for water managers to refine and optimise environmental flow strategies (e-flows) to balance water requirements for humans and nature. With increasing demands for freshwater and consequent declines in biodiversity, managers are faced with the problem of how to adaptively manage e-flows for multiple stakeholders and species whose flow requirements may overlap or vary. This study assessed the effectiveness of a regulated e-flow release strategy from a dam, aimed at providing movement opportunities and facilitating reproductive processes for multiple threatened species. Movements of 24 Mary River cod (Maccullochella mariensis), 20 Australian lungfish (Neoceratodus forsteri) and 13 Mary River turtle (Elusor macrurus) were quantified using acoustic telemetry over a three-year period. The influence of regulated e-flow releases, season, river depth, water temperature and rainfall on animal movements was assessed using Generalised linear mixed models (GLMMs). Models showed that hydraulic connectivity provided by both natural flows and regulated e-flow releases facilitated movement of all three species between pool habitats, throughout the year. Mary River turtles made extensive use of regulated e-flow releases when moving between habitats, whereas Mary River cod and Australian lungfish required additional natural rises in river height above the regulated e-flows to trigger movements. Significant movement activity was also recorded for cod and turtles during the dry season (winter and spring), broadly coinciding with breeding periods for these species. The effectiveness of, and potential improvements to, current e-flow strategies to sustain key life-history requirements of these species is discussed. Findings suggest a revised e-flow strategy with relatively minor increases in the magnitude of e-flow releases throughout winter and spring, would be effective in providing movement opportunities and supporting reproductive success for all three species. This study demonstrates that by quantifying movement behaviour in an e-flow context, ecological risk assessment frameworks can then be used to assess and provide for critical life-history requirements of multiple species within the context of a highly regulated system under increasing water use demands.


Assuntos
Espécies em Perigo de Extinção , Rios , Animais , Austrália , Ecossistema , Movimentos da Água
2.
Sci Rep ; 9(1): 5677, 2019 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-30952875

RESUMO

The modification of river flow regimes poses a significant threat to the world's freshwater ecosystems. Northern Australia's freshwater resources, particularly dry season river flows, are being increasingly modified to support human development, potentially threatening aquatic ecosystems and biodiversity, including fish. More information is urgently needed on the ecology of fishes in this region, including their habitat requirements, to support water policy and management to ensure future sustainable development. This study used electrofishing and habitat survey methods to quantify the dry season habitat use of 20 common freshwater fish taxa in the Daly River in Australia's wet-dry tropics. Of twenty measured habitat variables, water depth and velocity were the two most important factors discriminating fish habitat use for the majority of taxa. Four distinct fish habitat guilds were identified, largely classified according to depth, velocity and structural complexity. Ontogenetic shifts in habitat use were also observed in three species. This study highlights the need to maintain dry season river flows that support a diversity of riverine mesohabitats for freshwater fishes. In particular, shallow fast-flowing areas provided critical nursery and refuge habitats for some species, but are vulnerable to water level reductions due to water extraction. By highlighting the importance of a diversity of habitats for fishes, this study assists water managers in future decision making on the ecological risks of water extractions from tropical rivers, and especially the need to maintain dry season low flows to protect the habitats of native fish.


Assuntos
Peixes/fisiologia , Animais , Austrália , Biodiversidade , Conservação dos Recursos Naturais/métodos , Ecologia , Ecossistema , Água Doce , Rios , Alimentos Marinhos , Estações do Ano , Água
3.
J Fish Biol ; 79(6): 1525-44, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22136238

RESUMO

In this study, relationships between flow variation across multiple temporal scales and the distribution and abundance of three fish species, western rainbowfish Melanotaenia australis, sooty grunter Hephaestus fuliginosus and barramundi Lates calcarifer were examined at eight sampling reaches in the Daly River, Northern Territory, Australia. Discharge was highly seasonal during the study period of 2006-2010 with a distinct wet-dry discharge pattern. Significant catchment-wide correlations were identified between species abundance and hydrologic variables across several scales describing the magnitude and variability of flow. A Bayesian hierarchical model which accounted for >80% of variation in abundances for all species and age classes (i.e. juvenile and adult), identified the extent to which the influence of short-term flow variation was dependent upon the historical flow regime. There were distinct ontogenetic differences in these relationships for H. fuliginosus, with variability of recent flows having a negative effect on juveniles which was stronger at locations with higher historical mean daily flow. Lates calcarifer also displayed ontogenetic differences in relationships to flow variation with adults showing a positive association with increase in recent flows and juveniles showing a negative one. The effect of increased magnitude of wet-season flows on M. australis was negative in locations with lower historical mean daily flow but positive in locations with higher historical mean daily flow. The results highlighted how interactions between multiple scales of flow variability influence the abundance of fish species according to their life-history requirements.


Assuntos
Perciformes , Rios , Movimentos da Água , Animais , Teorema de Bayes , Modelos Estatísticos , Northern Territory , Densidade Demográfica
4.
J Fish Biol ; 77(3): 731-53, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20701651

RESUMO

This article examines the trophic ecology of freshwater fishes (22 species in 15 families) in a wet and dry tropical Australian river of high intra-annual and interannual hydrological variability. Seven major trophic groups were identified by cluster analysis; however, four food items (filamentous algae, chironomid larvae, Trichoptera larvae and Ephemeroptera nymphs) comprised almost half of the average diet of all species. The influence of species, fish size, spatial effects and temporal effects on food use was investigated using redundancy analysis. Size, time and space accounted for little of the perceived variation. Ontogenetic changes in diet were minor and limited to a few large species. Spatial variation in trophic composition of the fish assemblages reflected the effects of the Burdekin Falls and dam, a major geographic barrier, on species distributions. Little spatial variation in diet was detected after accounting for this biogeographical effect. Temporal variations in flow, although marked, had little effect on variations in fish diet composition due to the low temporal diversity of food resources in physically monotonous sand and gravel channels. Species identity accounted for<50% of the observed variation in food choice; omnivory and generalism were pronounced. The aquatic food web of the Burdekin River appears simple, supported largely by autochthonous production (filamentous and benthic microalgae, and to some extent, aquatic macrophytes). Allochthonous food resources appear to be unimportant. The generalist feeding strategies, widespread omnivory and absence of pronounced trophic segregation reported here for Burdekin River fishes may be common to variable and intermittent rivers of subtropical and tropical northern Australia with similar fish communities and may be a general feature of rivers of low habitat diversity and characterized by flow regimes that vary greatly both within and between years.


Assuntos
Dieta/veterinária , Peixes/fisiologia , Rios , Animais , Austrália , Análise por Conglomerados , Ecossistema , Peixes/anatomia & histologia , Peixes/crescimento & desenvolvimento , Cadeia Alimentar , Boca/anatomia & histologia , Fatores de Tempo , Clima Tropical
6.
Image J Nurs Sch ; 29(3): 229-35, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9378477

RESUMO

PURPOSE: To examine nurse-patient communication about preferences for cardiopulmonary resuscitation (CPR). DESIGN: Prospective cohort. Sampled were patients and nurses caring for patients enrolled in SUPPORT (1989-91), a multicenter study of seriously-ill hospitalized adults at four U.S. hospitals. METHODS: Information about patient preferences was obtained by interviews with patients and their designated surrogates. For selected patients, nurses were interviewed prospectively about their understanding of patients' preferences and whether they discussed these preferences with their patients. Nurse demographic information was obtained by questionnaire. Additional patient data were obtained by interview and chart review. Logistic regression was used to identify independent correlates of nurse-patient communication and nurses' understanding of patients' preferences. FINDINGS: For 1,763 study patients, 1,427 nurse interviews (response rate 81%) were obtained. The median age of interviewed nurses was 29 years; 96% were women, 68% had a bachelor's or master's degree, and 62% had worked for 5 years or more as a nurse. Nurses reported discussions about CPR with 13% of their patients, and these discussions were more likely if the nurse thought the patient did not want CPR (adjusted odds ratio [AOR] 2.68; 95% CI 1.84 to 3.90), if the nurse had spent more time with the patient (AOR 1.05; 95% CI 1.02 to 1.08) per 5 additional days, if the patient had metastatic cancer (AOR 3.56; 95% CI 1.86 to 6.78), or if the patient was in an intensive care unit at the time of study entry (AOR 2.08; 95% CI 1.26 to 3.42). Diagnosis and study site were also associated with nurses' reports of discussions with patients. Of 551 patients with available data, 58% (n = 317) wanted CPR and 30% (n = 164) did not. Nurses understood patients' CPR preferences correctly for 74% of the patients. Nurses were more likely to understand patients' preferences to forego CPR if the patient was 75 years of age or older (AOR 6.6; 95% CI 2.0 to 22.0) or if the nurse and patient had discussed the patient's preferences (AOR 25.3; 95% CI 6.5 to 98.6) or if the patient had cancer (AOR 10.9; 95% CI 2.3 to 50.1). Nurses' understanding of patients' preferences for CPR was no better than that of physicians or patients' surrogate decision-makers. CONCLUSIONS: In this sample of seriously ill hospitalized adults, discussions between patients and nurses about CPR were infrequent. Nurses' understanding of patients' preferences for care was similar to that of physicians and patients' surrogate decision-makers. Educational interventions should focus on increasing the frequency of nurse-patient discussions about end-of-life care and improving nurses' understanding of patients' preferences for care.


Assuntos
Reanimação Cardiopulmonar , Relações Enfermeiro-Paciente , Participação do Paciente , Ordens quanto à Conduta (Ética Médica) , Adulto , Idoso , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Curva ROC , Estatísticas não Paramétricas , Estados Unidos
7.
Clin Nurs Res ; 5(2): 199-219, 1996 May.
Artigo em Inglês | MEDLINE | ID: mdl-8704666

RESUMO

The purpose of this study is to describe the involvement of nurses in the decision-making process of seriously ill hospitalized adults. Nurses (696) completed interviews with 1,427 patients. Patient, surrogate, and physician interviews were also completed. Patients and surrogates perceive the nurse as more influential in decision making than does the nurse or physician. Many nurses reported having no (31%) or little (36%) knowledge of their patients' preferences, and 53% of the nurses did not advocate for their patients' preferences. Only 50% of the nurses reported educating their patients about the treatment plan chosen or discussing treatment options with their patients, and few (17%) discuss prognosis. This study indicates nurses are not actively involved in the decision-making process of their patients, especially older or more experienced nurses and those working in intensive care units.


Assuntos
Tomada de Decisões , Recursos Humanos de Enfermagem Hospitalar , Papel (figurativo) , Assistência Terminal/psicologia , Adulto , Idoso , Atitude do Pessoal de Saúde , Atitude Frente a Saúde , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Educação de Pacientes como Assunto , Prognóstico , Inquéritos e Questionários
8.
J Cardiovasc Nurs ; 9(3): 68-77, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7782815

RESUMO

The methods of the Study to Understand Prognosis and Preferences of Outcomes and Risks of Treatment (SUPPORT), a five year, five-center study of decision making and communication in patients near the end of life, are described. Aspects of the study propose to describe the role of the staff nurse and the specially trained nurse facilitator in decision making in patients near the end of life. The nurse is in a unique position to initiate discussions about patient preferences for end-of-life treatment and quality of life; however, a review of related research describes discordance between clinicians' understanding and patients' preferences for treatment. Ethical issues, practice barriers, and practice innovations in end-of-life treatment are discussed.


Assuntos
Ética em Enfermagem , Relações Enfermeiro-Paciente , Ordens quanto à Conduta (Ética Médica) , Assistência Terminal , Estudos de Coortes , Humanos , Relações Interprofissionais , Avaliação em Enfermagem , Equipe de Assistência ao Paciente , Estudos Prospectivos , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto
10.
Anesth Analg ; 67(1): 64-8, 1988 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3337347

RESUMO

Reports of whether or not bupivacaine affects neonatal neurobehavior have been contradictory. The purpose of this study was to test the hypothesis that scores on the Brazelton Neonatal Behavioral Assessment Scale (BNBAS) after epidural anesthesia with bupivacaine for cesarean section would not be different than those after chloroprocaine. Furthermore, if there were any effects, it was hypothesized that they would be related to cord blood levels of the drug. Fifty-five healthy mother/infant pairs were studied. Clinical characteristics, pharmacologic data, and BNBAS scores were obtained and analyzed using statistical techniques that included t-tests, repeated measures analysis of variance, and stepwise multiple regression. The results indicate that infants in the bupivacaine group do significantly better than those in the chloroprocaine group in the orientation cluster of the BNBAS (F[1,49] = 22, P less than 0.001); this cluster reflects higher cortical functioning. Furthermore, there was improvement in the bupivacaine group in the regulation of state cluster with age, whereas there was no improvement in the chloroprocaine group (F[1,53] = 4.34, P less than 0.01). This study suggests that performance on the BNBAS after exposure to bupivacaine is better than that after exposure to chloroprocaine.


Assuntos
Anestesia Epidural , Anestesia Obstétrica , Anestésicos Locais , Bupivacaína , Cesárea , Sistema Nervoso/efeitos dos fármacos , Procaína/análogos & derivados , Anestésicos Locais/efeitos adversos , Anestésicos Locais/sangue , Bupivacaína/efeitos adversos , Bupivacaína/sangue , Avaliação de Medicamentos , Feminino , Humanos , Recém-Nascido , Exame Neurológico/métodos , Gravidez , Procaína/efeitos adversos , Procaína/sangue
11.
Arch Environ Health ; 41(5): 287-91, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-3800431

RESUMO

It has been suggested that lead (Pb) at low exposure levels is a behavioral teratogen. Blood lead (Pb-B) was measured in 185 samples of maternal blood and in 162 samples of cord blood drawn from members of a cohort of mother-infant pairs. Routine newborn assessments, an examination for minor anomalies, the Brazelton Neonatal Behavioral Assessment (NBAS), and part of the Graham/Rosenblith Behavioral Examination (G/R) were administered. Maternal and cord Pb-B correlated 0.80. In regression analyses, Apgar scores, birthweight, length, head circumference, neonatal anomalies, and seven behavioral scales were unrelated to either maternal or cord Pb-B. Three scales--the NBAS Abnormal Reflexes, the G/R Neurological Soft Sign, and the G/R Muscle Tonus Scales--were related minimally to either cord or maternal Pb-B. Because of the contrast in maternal and cord results, despite the high correlation of maternal and cord Pb-B, the data were reanalyzed for 132 cases with paired data. Only the Soft Sign Scale remained significant and that only for cord, but not maternal Pb-B. Regression analysis revealed a suppression with the Soft Sign Scale related to the variance of the cord Pb-B that was not common with maternal Pb-B. The possibility that the fetus under stress tends to accumulate Pb was considered.


Assuntos
Desenvolvimento Embrionário e Fetal/efeitos dos fármacos , Sangue Fetal/análise , Chumbo/sangue , Teratogênicos , Consumo de Bebidas Alcoólicas , Índice de Apgar , Feminino , Humanos , Recém-Nascido , Chumbo/toxicidade , Troca Materno-Fetal , Placenta/análise , Gravidez , Reflexo Anormal/induzido quimicamente , Fumar
12.
Alcohol Clin Exp Res ; 9(5): 447-53, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-3904510

RESUMO

Fetal alcohol effects in 359 infants born to disadvantaged women identified as having a history of alcohol abuse or as controls and who provided reports of alcohol use in pregnancy are being studied in a prospective design. Alcohol abuse was assessed with the Michigan Alcoholism Screening Test (MAST). Alcohol use (AA/day) was based on short-term recall covering 2-week periods prior to each antenatal visit. A tally of anomalies associated with fetal alcohol syndrome was obtained in a blinded examination of each infant. This tally was significantly related to the MAST classification and, for the MAST+ subjects, the tally was related to first trimester AA/day. Birth weight, length, and head circumference were negatively correlated with AA/day (entire pregnancy); however, the effect was attenuated and not statistically significant in models with covariate control. It is possible that these measures were near the threshold of effect. Scale scores of the Brazelton Neonatal Behavioral Assessment Scale and three scale scores of the Graham/Rosenblith Behavioral Examination of the Neonate were unrelated to the MAST classification and to AA/day.


Assuntos
Transtornos do Espectro Alcoólico Fetal/epidemiologia , Anormalidades Induzidas por Medicamentos/epidemiologia , Alcoolismo/diagnóstico , Feminino , Transtornos do Espectro Alcoólico Fetal/diagnóstico , Retardo do Crescimento Fetal/epidemiologia , Humanos , Recém-Nascido , Gravidez , Complicações na Gravidez/diagnóstico , Primeiro Trimestre da Gravidez
13.
Anesth Analg ; 64(3): 335-42, 1985 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-3977093

RESUMO

After meperidine administration during labor, meperidine reaches its highest level in fetal tissues within 2-3 hr. The highest levels of normeperidine, the active metabolite of meperidine, are, on the other hand, determined in fetal tissues by the time between administration of meperidine to the mother and delivery: the greater the drug-to-delivery interval (DDI), the higher the fetal levels of normeperidine. Because of the different times to peak fetal levels of meperidine and normeperidine, it may be possible to partially separate the effects of meperidine and its metabolite on the neonate using the DDI. The purpose of this study was to determine whether low doses of meperidine affected performance on the Brazelton Neonatal Behavioral Assessment Scale (BNBAS), and whether this performance is related to the DDI or to levels of meperidine or to normeperidine. Sixteen control neonates whose mothers received no meperidine and 41 study infants whose mothers received 25-100 mg meperidine intravenously (mean 39 +/- 19 mg) were studied. Comparisons of BNBAS scores of control and study infants measured at less than 12 hr, again at 3 days of age, and the effect of DDI were made using repeated measures analyses of variance (ANOVA). Correlation techniques were used to examine relationships between BNBAS performance and clinical and pharmacological variables related to drug administration. The BNBAS cluster scores representing regulation of state and number of abnormal reflexes were significantly different in study neonates from control neonates. Performance depended upon test day. Further analysis showed that longer DDIs resulted in less optimal BNBAS performance.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Comportamento Infantil/efeitos dos fármacos , Recém-Nascido , Meperidina/farmacologia , Reflexo/efeitos dos fármacos , Adulto , Anestesia Obstétrica , Feminino , Sangue Fetal/análise , Humanos , Meperidina/sangue , Gravidez , Fatores de Tempo
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