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1.
J Fish Biol ; 88(5): 1731-45, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27170108

RESUMO

Coral reef fish communities were sampled at the Nayband Marine Park, Iran, using baited remote underwater video stations (BRUVSs) which incorporated animal (i.e. frigate tuna Auxis thazard and beef liver), or plant-based baits (i.e. raw dough and raw dough-turmeric powder mix). The A. thazard was found to record significantly (P < 0·05) higher species richness and number of carnivorous fishes than plant-based baits, while abundance of herbivores was maximum in raw dough-turmeric powder mix trials. There was also a significant difference in trophic composition of fish assemblages surveyed by animal- and plant-based baits which seemed to be due to variations in attraction patterns of carnivores and herbivores occurring at the earlier phases of each BRUV deployments. Meanwhile, the assemblage structure was comparable among fish assemblages sampled by different bait treatments, indicating that species-level responses to each bait type may be more complicated. In essence, the efficiency of mixed baits should also be examined in future studies.


Assuntos
Biodiversidade , Recifes de Corais , Peixes/fisiologia , Animais , Comportamento Alimentar , Cadeia Alimentar , Irã (Geográfico) , Perciformes
2.
J Fish Biol ; 85(5): 1413-28, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25098708

RESUMO

The aim of this study was to determine and compare habitat preferences for male and female adult and juvenile White's seahorse Hippocampus whitei and assess their movements and site fidelity over 4 years. Data were collected from three sites along 1.5 km of estuarine shoreline in Port Stephens, New South Wales, Australia, from 2006 to 2009 using H. whitei that had been tagged with visible implant fluorescent elastomer. Relative availability of 12 habitats and habitat preferences of H. whitei was determined, based on the habitat that H. whitei used as a holdfast. Hippocampus whitei occurred in nine different habitats; adults preferred sponge and soft coral Dendronephthya australis habitats with no difference between male and female habitat preferences whilst juveniles preferred gorgonian Euplexaura sp. habitat. There was a significant preference by adults for D. australis colonies with height >40 cm and avoidance of colonies <20 cm. Neither adults nor juveniles used sand or the seagrasses Zostera muelleri subsp. capricorni and Halophila ovalis. Hippocampus whitei showed cryptic behaviour with c. 50% of adult sightings cryptic and c. 75% for juveniles with crypsis occurring predominantly in Sargassum sp. for adults and Euplexaura sp. habitat for juveniles. Within sites, females moved significantly longer distances (maximum of 70 m) than males (maximum of 38 m) over 20 months. Strong site fidelity was displayed by H. whitei with males persisting at the same site for up to 56 months and females for 49 months and no H. whitei moved between sites. The longest period that an H. whitei was recorded on the same holdfast was 17 months for a male and 10 months for a female. As this species displays strong site fidelity, specific habitat preferences and has a limited distribution, future management needs to minimize the risk of habitat disturbance as loss of key habitats could have a negative effect on species abundance and distribution.


Assuntos
Comportamento de Escolha , Ecossistema , Fatores Sexuais , Smegmamorpha/fisiologia , Animais , Comportamento Animal , Conservação dos Recursos Naturais , Feminino , Masculino , New South Wales
3.
J Theor Biol ; 360: 271-278, 2014 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-25058806

RESUMO

Models of near-exclusive predator-prey systems such as that of the Canadian lynx and snowshoe hare have included factors such as a second prey species, a Holling Type II predator response and climatic or seasonal effects to reproduce sub-sets of six signature patterns in the empirical data. We present an agent-based model which does not require the factors or constraints of previous models to reproduce all six patterns in persistent populations. Our parsimonious model represents a generalised predator and prey species with a small prey refuge. The lack of the constraints of previous models, considered to be important for those models, casts doubt on the current hypothesised mechanisms of exclusive predator-prey systems. The implication for management of the lynx, a protected species, is that maintenance of an heterogeneous environment offering natural refuge areas for the hare is the most important factor for the conservation of this species.


Assuntos
Ecossistema , Cadeia Alimentar , Modelos Biológicos , Comportamento Predatório/fisiologia , Comportamento Espacial/fisiologia , Animais , Simulação por Computador , Lebres/fisiologia , Lynx/fisiologia , Dinâmica Populacional
4.
J Fish Biol ; 83(5): 1344-53, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24131331

RESUMO

The effect of flash photography on seahorse species has never been tested. An experiment was established to test the effect of flash photography and the handling of Hippocampus whitei, a medium-sized seahorse species endemic to Australia, on their behavioural responses, movements and site persistence. A total of 24 H. whitei were utilized in the experiment with eight in each of the three treatments (flash photography, handling and control). The effect of underwater flash photography on H. whitei movements was not significant; however, the effect of handling H. whitei to take a photograph had a significant effect on their short-term behavioural responses to the photographer. Kaplan-Meier log-rank test revealed that there was no significant difference in site persistence of H. whitei from each of the three treatments and that flash photography had no long-term effects on their site persistence. It is concluded that the use of flash photography by divers is a safe and viable technique with H. whitei, particularly if photographs can be used for individual identification purposes.


Assuntos
Comportamento Animal/efeitos da radiação , Fotografação , Smegmamorpha/fisiologia , Animais , Feminino , Luz , Locomoção , Masculino , New South Wales
5.
J Environ Manage ; 114: 84-91, 2013 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-23220604

RESUMO

Marine protected areas (MPAs) are a primary policy instrument for managing and protecting coral reefs. Successful MPAs ultimately depend on knowledge-based decision making, where scientific research is integrated into management actions. Fourteen coral reef MPA managers and sixteen academics from eleven research, state and federal government institutions each outlined at least five pertinent research needs for improving the management of MPAs situated in Australian coral reefs. From this list of 173 key questions, we asked members of each group to rank questions in order of urgency, redundancy and importance, which allowed us to explore the extent of perceptional mismatch and overlap among the two groups. Our results suggest the mismatch among MPA managers and academics is small, with no significant difference among the groups in terms of their respective research interests, or the type of questions they pose. However, managers prioritised spatial management and monitoring as research themes, whilst academics identified climate change, resilience, spatial management, fishing and connectivity as the most important topics. Ranking of the posed questions by the two groups was also similar, although managers were less confident about the achievability of the posed research questions and whether questions represented a knowledge gap. We conclude that improved collaboration and knowledge transfer among management and academic groups can be used to achieve similar objectives and enhance the knowledge-based management of MPAs.


Assuntos
Conservação dos Recursos Naturais , Recifes de Corais , Academias e Institutos , Austrália , Governo , Pesquisa
6.
J Fish Biol ; 81(4): 1297-314, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22957871

RESUMO

The aim of this study was to collect data on population dynamics and life history for White's seahorse Hippocampus whitei, a geographically restricted species that is listed as data deficient under the IUCN Red List. Data from H. whitei populations were collected from two regions, Port Stephens (north) and Sydney Harbour (south) in New South Wales, Australia, covering most of the known range of H. whitei, from 2005 to 2010. Over 1000 individuals were tagged using fluorescent elastomer and on subsequent recaptures were re-measured for growth data that were used in a forced Gulland-Holt plot to develop growth parameters for use in a specialized von Bertalanffy growth-function model. Growth parameters for Port Stephens were: females L(∞) = 149·2 mm and K = 2·034 per year and males L(∞) = 147·9 mm and K = 2·520 per year compared with estimates from Sydney Harbour: females L(∞) = 139·8 mm and K = 1·285 per year and males L(∞) = 141·6 mm and K = 1·223 per year. Whilst there was no significant difference in growth between sexes for each region, H. whitei in Port Stephens grew significantly quicker and larger and matured and reproduced at a younger age than those from Sydney Harbour. The life span of H. whitei is at least 5 years in the wild with six individuals recorded reaching this age. Data collected on breeding pairs found that H. whitei displays life-long monogamy with three pairs observed remaining pair bonded over three consecutive breeding years. Baseline population densities were derived for two Port Stephens' sites (0·035 and 0·110 m(-2)) and for Manly in Sydney Harbour (1·050 m(-2)). Even though the life-history parameters of H. whitei suggest it may be reasonably resilient, precaution should be taken in its future management as a result of its limited geographical distribution and increasing pressures from anthropogenic sources on its habitats.


Assuntos
Reprodução/fisiologia , Smegmamorpha/fisiologia , Animais , Tamanho Corporal , Feminino , Longevidade/fisiologia , Masculino , New South Wales , Densidade Demográfica , Dinâmica Populacional , Estações do Ano , Comportamento Sexual Animal/fisiologia , Maturidade Sexual , Smegmamorpha/anatomia & histologia , Smegmamorpha/crescimento & desenvolvimento
7.
Acta Paediatr ; 81(1): 79-81, 1992 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1376181

RESUMO

An infant with delayed development and peripheral myopathy, nourished on a soy-based liquid diet deficient in carnitine, had gastrointestinal dysmotility manifested by postprandial vomiting, oral drooling, delayed gastric emptying and infrequent bowel movements. Oesophageal manometry showed a reduced lower oesophageal sphincter pressure for age with abnormal distal motility. Serum carnitine concentration was 9.9 mumol l-1. After dietary supplementation of carnitine the gastrointestinal symptoms resolved, oesophageal manometry returned to normal, and serum carnitine increased to 37.2 mumol l-1. Dietary carnitine deficiency in infancy may be a cause of smooth muscle dysmotility of the gastrointestinal tract.


Assuntos
Carnitina/deficiência , Gastroenteropatias/etiologia , Alimentação com Mamadeira , Pré-Escolar , Constipação Intestinal/etiologia , Constipação Intestinal/fisiopatologia , Deficiências do Desenvolvimento/etiologia , Alimentos Fortificados , Gastroenteropatias/diagnóstico , Gastroenteropatias/fisiopatologia , Motilidade Gastrointestinal , Humanos , Lactente , Recém-Nascido , Masculino , Músculo Liso/fisiopatologia , Sialorreia/etiologia
8.
Brain Res ; 525(1): 45-58, 1990 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-2245325

RESUMO

Overt circadian rhythms are permanently disrupted following lesions of the suprachiasmatic nucleus (SCN) in hamsters. It has previously been demonstrated that whole tissue grafts which include the fetal SCN restore circadian locomotor rhythms to hamsters previously made arrhythmic by SCN lesions. In the present study, we ask whether the intrinsic peptidergic organization of the SCN is a prerequisite for functional recovery of circadian rhythms of locomotor activity. To this end, dispersed cell suspensions of [3H]thymidine-labelled fetal anterior hypothalamic tissue which contains the SCN, were injected stereotaxically into the brain of adult hamsters. Dispersed cell suspensions restored free-running locomotor rhythms, but not entrainment or gonadal regression. The period of the restored free-running rhythms following injections of SCN cell suspensions was shorter than 24 h, in contrast to intact hamsters and SCN-lesioned hamsters whose rhythms are restored by whole tissue grafts. In animals with restored rhythms, a majority of [3H]thymidine-labelled cells were located within nuclei of the midline thalamus and zona incerta. In a few individuals, donor cells were also deposited along the injection tract as far ventrally as the medial hypothalamus. Restoration of free-running locomotor rhythmicity was correlated with the presence of small numbers of isolated VIP cells along with small plexuses of VIP fibers. In animals which did not recover locomotor rhythmicity, grafts were identical in location and size to those in recovered hamsters, but did not contain peptidergic cells characteristic of the SCN. The results suggest that structural integrity of the fetal SCN is not necessary for restoration of rhythmicity after grafting.


Assuntos
Transplante de Tecido Encefálico/fisiologia , Ritmo Circadiano/fisiologia , Transplante de Tecido Fetal/fisiologia , Núcleo Supraquiasmático/embriologia , Núcleo Supraquiasmático/fisiologia , Animais , Cricetinae , Imuno-Histoquímica , Injeções Intraventriculares , Masculino , Mesocricetus , Atividade Motora/fisiologia , Núcleo Supraquiasmático/citologia
9.
Aust Health Rev ; 11(2): 110-21, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-10290490

RESUMO

2,200 enrolled nurses (ENs) in N.S.W. were surveyed about their current participation in the workforce. The survey showed that ENs tended to move in and out the workforce. More than 75% of respondents had left the EN workforce during their career for an average period of five years. The employment status of three cohorts (1980, 1982, and 1984) of ENs as examined over several years. Most losses from a cohort occurred within the first 12 months; trainee ENs showed the highest losses. Two important movements by ENs in recent years were uncovered. There has been an increase in the proportion of respondents working part-time and casual. Also, in more recent years ther has been an increased return of ENs to the workforce, resulting in a net gain in employment in 1985. In the latter case it appears that the increased returns follow a peak in the number of ENs trained in the late 1970s. As such, the growth in employment in unlikely to continue. The increase in the rate of return may also relate to the shortage of RNs. Shortages of nurses may have increased the opportunities for part-time or preferred shifts employment which attracted ENs to return to the workforce. ENs seem to leave the workforce due to family reasons particularly child bearing. The most frequently mentioned reason for returning to work is financial necessity. Whilst the turnover indicated in this study is high the net wastage is very low. Whilst the rate of loss remains constant the rate of return increases. It is difficult to determine whether the low wastage rate means that ENs are not as dissatisfied as they reported in this study or that they do not have better employment opportunities.


Assuntos
Emprego/estatística & dados numéricos , Enfermeiras e Enfermeiros/provisão & distribuição , New South Wales , Inquéritos e Questionários
10.
Med J Aust ; 147(7): 339-41, 1987 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-3657660

RESUMO

Education in Australian medical schools is presently under review, including teaching about alcohol and other drugs. In August 1986, the Alcohol and Drug Foundation, Australia (ADFA) presented to the Deans of Australasian medical faculties (including those of Fiji, Papua New Guinea, and New Zealand) a number of options to develop the alcohol and other drugs content of medical courses. It was proposed that a coordinator of education in alcohol and other drugs be appointed in medical faculties; this proposal had been modelled on the US Career Teacher Training Program in Alcohol and Drug Abuse. The Deans expressed interest in ADFA's proposal. This paper discusses the role of undergraduate medical education in alcohol and other drugs, and the background to, and some guide-lines from, the ADFA proposal.


Assuntos
Alcoolismo , Educação de Graduação em Medicina , Transtornos Relacionados ao Uso de Substâncias , Austrália , Currículo , Fiji , Humanos , Nova Zelândia , Papua Nova Guiné , Faculdades de Medicina
11.
J Neurosci ; 7(6): 1626-38, 1987 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-3598638

RESUMO

It is well established that overt circadian rhythms are permanently disrupted following lesions of the hamster hypothalamic suprachiasmatic nucleus (SCN). In the present study, we show that implantations of brain grafts containing the fetal SCN reestablish circadian rhythms of locomotor activity in adult hamsters previously made arrhythmic by SCN lesions. The restoration of free-running rhythms in conditions of constant darkness is correlated with the presence in the graft of neuropeptides normally present in the SCN of unlesioned hamsters, including vasoactive intestinal polypeptide (VIP), neuropeptide Y (NPY), and vasopressin (VP). In several recipients, grafts were found to receive retinal input, and appeared to send efferents into the host brain. Not all functions of the SCN were reinstated by the graft: animals with restored locomotor rhythms did not show gonadal regression in the absence of light, and failed to synchronize (entrain) to light intensities to which SCN-intact animals responded.


Assuntos
Encéfalo/cirurgia , Ritmo Circadiano , Núcleo Supraquiasmático/transplante , Animais , Encéfalo/metabolismo , Cricetinae , Histocitoquímica , Imunoquímica , Masculino , Mesocricetus , Atividade Motora/fisiologia , Vias Neurais/fisiologia , Neuropeptídeos/metabolismo , Retina/fisiologia , Núcleo Supraquiasmático/embriologia
13.
J Reprod Med ; 14(4): 138-43, 1975 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1142349

RESUMO

Coagulation and fibrinolytic profiles have been studied in two groups of sterility patients receiving low dosage regimens of human gonadotropins for ovarian stimulation. This investigation was prompted by a report of two patients with severe episodes of intravascular coagulation associated with periods of "hyperstimulation" from these drugs. No statistically significant changes were found as a result of administration of one ampoule of human menopausal (HMG) or pituitary gonadotropins (HPG) for 8 days followed by 9000 units of human chorionic gonadotrophin (HCG). A course of 2-3 ampoules HMG on alternate days for longer periods of time prior to administration of HCG also failed to produce significant alterations of the coagulation or fibrinolytic mechanisms. In two patients with severe hyperstimulation there were elevated levels of factor V, platelets, fibrinogen, profibrinolysin, and fibrinolytic inhibitors. Generation of thromboplastin was also increased when plasma was diluted one to fifty in the thromboplastin generation test. These results suggest a possibly increased coagulation potential in patients with "hyperstimulation syndrome" but not in those receiving the low dosage regimens of human gonadotropins more commonly used for ovarian stimulation at the present time.


Assuntos
Fatores de Coagulação Sanguínea/biossíntese , Coagulação Sanguínea/efeitos dos fármacos , Fibrinólise/efeitos dos fármacos , Gonadotropinas/farmacologia , Síndrome de Meigs/sangue , Testes de Coagulação Sanguínea , Gonadotropina Coriônica/administração & dosagem , Gonadotropina Coriônica/efeitos adversos , Gonadotropina Coriônica/farmacologia , Estrogênios/metabolismo , Fator V/biossíntese , Feminino , Fibrinogênio/biossíntese , Gonadotropinas Hipofisárias/administração & dosagem , Gonadotropinas Hipofisárias/efeitos adversos , Gonadotropinas Hipofisárias/farmacologia , Humanos , Infertilidade Feminina/tratamento farmacológico , Síndrome de Meigs/induzido quimicamente , Menotropinas/administração & dosagem , Menotropinas/efeitos adversos , Menotropinas/farmacologia , Progestinas/metabolismo , Tromboplastina/biossíntese , Trombose/etiologia , Fatores de Tempo
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