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1.
Radiography (Lond) ; 30(1): 52-60, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37866158

RESUMO

INTRODUCTION: The timely communication of clinically significant image appearances to Emergency Department (ED) referrers is necessary for optimum patient care. Australian reliance on verbal communication only is time-limited, open to misinterpretation and lacks transparency. A combined radiographer alert and comment model was designed to reliably communicate image abnormalities to ED referrers in real-time. METHODS: A multidisciplinary steering group designed the model for all ED general imaging. Protocols were developed to document radiographer comments (critical, urgent and clinically significant) in patients' medical records. Critical findings were communicated directly to ED. Five NSW hospitals varying in size, complexity and population demographics piloted the model between three to twelve months during 2021-2022. Site auditors compared comments with the radiology report and designated each as True Positive (TP), False Positive (FP), indeterminate and clinically significant. Indeterminate cases were analysed by an external radiologist. Inter-observer consensus was obtained for all classifications via two independent auditors. The Positive Predictive Value (PPV), or precision of the comment, was calculated for each site. RESULTS: Radiographers (n = 69) provided comments for 1102 cases. The pooled average PPV for TP was 0.96; (0.947-0.971; 95% CI). The weighted mean error (FP comments) was 3.9%; (2.9% - 5.3%.; 95% CI). CONCLUSION: The Radiographer Comment model provided consistent levels of commenting precision and reproducibility across a range of sites with a pooled average PPV (0.96). The False Positive rate or weighted mean error (FP) of 3.9% (2.9% - 5.3%.; 95% CI) was low. IMPLICATIONS FOR FUTURE PRACTICE: A strategic, interprofessional approach in the implementation of an image alert combined with a Radiographer Comment can be adapted across a variety of hospital settings for ED and other departments.


Assuntos
Serviço Hospitalar de Emergência , Humanos , Raios X , Reprodutibilidade dos Testes , Projetos Piloto , Austrália
2.
Mar Environ Res ; 173: 105527, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34813993

RESUMO

Whether wild fish populations are food limited in some inshore and estuarine marine ecosystems is an area of increasing research and focus. To investigate this phenomenon, the abundance and behaviours of fish in a temperate South Pacific estuary were observed in response to the provision of supplementary feed. Observations were conducted over 120-weeks, involving a 60-week period over which fish were actively fed followed by a 60 week without feeding. During active feeding, estuarine associated fish (primarily yellow-eyed mullet Aldrichetta forsteri) showed a highly predictable pattern of fish abundance, biomass and behavioural formation coinciding with the almost daily feeder operation. Tidal current velocities and turbidity appeared to have little influence on the attendance and formations of fish over this period, although season did influence some variables. Peaking at close to 9000 individual fish and 880 kg biomass, fish attendance during the operation of the feeding station was markedly higher than during the period when the feed station was no longer active. Whereby only 0-100 individuals were typically present, and fish no longer showed collective behavioural formations. A direct result of the large number of fish aggregating on this feeding station was an increase in the secondary productivity of the observable zone around the feeding station. Whereby secondary productivity increased by a factor of ∼30 above that observed when the feed station was not operating. Supplementary feeding effectively transformed the study site - a highly modified intertidal location - from an area of very low productivity to one comparable with highly productive temperate estuary environments described elsewhere. The behavioural drivers and ecological relevance of these observations are discussed.


Assuntos
Ecossistema , Pesqueiros , Animais , Estuários , Peixes , Alimentos , Humanos
3.
J Fish Biol ; 97(2): 465-478, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32419147

RESUMO

To investigate whether wild fish populations are food limited, this study explored whether the provision of supplementary food had a positive effect on the abundance, condition and growth characteristics of estuarine fish assemblages in New Zealand. Feed (7690 kg) was delivered from an anthropogenic feeding station over a 60-week period to a naturally occurring assemblage of wild fish. Yellow-eyed mullet (Aldrichetta forsteri) of juvenile, sub-adult and newly matured size classes were the dominant species actively foraging at the feeding station throughout its operation, whereas larger piscivorous species visited and foraged from the feed station over the summer period only. Other species were present in the wider area of Nelson Haven, but not at the feed station. No obvious changes in the condition factor of yellow-eyed mullet were observed across the period of monitoring, and no changes in their catchability were detected - although marked seasonal variation in catch rates was observed. Results from tag-recapture data identify that the length-based growth rates of yellow-eyed mullet recaptured near the feed station were higher than those of tagged individuals recaptured at a nearby comparison site, and were higher than the growth rates observed in natural populations of yellow-eyed mullet in the wider region. Shifts in the median size of fish, as observed by acoustic observations, agreed with the tag-recapture data. Although some of the results identified were not amenable to statistical analyses, the attendance of yellow-eyed mullet at the feeding station, in combination with the improved estimates of growth by most of the techniques employed, indicates that yellow-eyed mullet are food limited in their natural environment and that the growth performance of these fish can be positively affected by the increased availability of food.


Assuntos
Estuários , Pesqueiros , Peixes/fisiologia , Animais , Ecossistema , Alimentos , Nova Zelândia , Estações do Ano
4.
J Comp Physiol B ; 190(2): 169-183, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31996987

RESUMO

Shallow coastal and estuarine habitats function as nurseries for many juvenile fish. In this comparative study, metabolic profiles of two New Zealand finfish, snapper (Chrysophrys auratus) and yellow-eyed mullet-YEM (Aldrichetta forsteri) that as juveniles share the same temperate coastal environments, were examined. Metabolic parameters (routine and maximum metabolic rates, and specific dynamic action-SDA) were investigated at a set of temperatures (13, 17, 21 °C) within the range juveniles both species experience annually. SDA was also determined for a range of different feed rations to investigate the effects of meal size on postprandial metabolic response. Temperature was a strong modulator of snapper and YEM metabolic profile (routine and maximum metabolic rates, and absolute and factorial aerobic scope). Metabolic rates increased with temperature in both species as did absolute scope in YEM, though for snapper, it was only greater at the highest temperature. Factorial scope behaved in the same fashion for the two species, being greatest at 13 °C. Both absolute and factorial scope were ~ twofold greater in YEM than in snapper across the entire temperature range. Temperature also affected SDA response in snapper, while in YEM, SDA parameters were largely unaffected when temperature increased from 17 to 21 °C. Snapper were able to consume a large range of meal sizes (0.5-3.0% body mass-BM) with meal sizes > 1% BM having a pronounced effect on numerous SDA parameters, whereas mullet appeared to consume more limited ration sizes (≤ 1.0% BM). In both species, rations ≤ 1% BM produced similar changes in SDA parameters identifying comparable digestive bio-energetics. Overall, our metabolic characterisations demonstrate that both species can adjust to the variable temperate environmental temperatures and manage the energetic costs of digestion and feed assimilation. Yet, despite these general similarities, YEM's greater aerobic scope may point to better physiological adaptation to the highly variable temperate coastal environment than were observed in snapper.


Assuntos
Perciformes/fisiologia , Animais , Metabolismo Energético , Comportamento Alimentar/fisiologia , Nova Zelândia , Consumo de Oxigênio/fisiologia , Perciformes/classificação , Perciformes/metabolismo , Período Pós-Prandial , Temperatura
5.
Artigo em Inglês | MEDLINE | ID: mdl-28600601

RESUMO

The lateral line system is a mechanosensory organ found in all fish species and located on the skin or in subdermal canals. The basic functional units are superficial and canal neuromasts, which are involved in hydrodynamic sensing and cohesion in schooling fish. Yellow-eyed mullet (Aldrichetta forsteri) are an obligate schooling species found commonly in shallow coastal areas of New Zealand and Australia. Schooling is a fundamental part of their behavioural repertoire, yet little is known about the structure or functionality of the lateral line in this species. We used scanning electron microscopy to characterise the morphology of trunk superficial neuromasts. We then took a multi-sensory approach and conducted behavioural experiments comparing school structure in groups of fish with and without fully functioning lateral lines, under photopic and scotopic conditions. A highly developed hydro-sensing system exists on the trunk of yellow-eyed mullet consisting of superficial neuromasts containing hundreds of hair cells aligned, with respect to their most sensitive axis, in a rostrocaudal direction. Without functioning superficial neuromasts, schooling behaviour was disrupted under both photopic and scotopic conditions and the ability to detect stationary objects decreased. Results highlight the importance of this component of the lateral line system to schooling behaviour.


Assuntos
Meio Ambiente , Mecanorreceptores/fisiologia , Smegmamorpha/anatomia & histologia , Smegmamorpha/fisiologia , Comportamento Social , Animais , Corpo Ciliar/ultraestrutura , Combinação de Medicamentos , Estradiol/análogos & derivados , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Sistema da Linha Lateral/anatomia & histologia , Sistema da Linha Lateral/fisiologia , Sistema da Linha Lateral/ultraestrutura , Mecanorreceptores/ultraestrutura , Microscopia Eletrônica de Varredura , Rede Nervosa/fisiologia , Rede Nervosa/ultraestrutura , Noretindrona , Natação , Testosterona/análogos & derivados , Gravação em Vídeo
6.
J Comp Physiol B ; 184(4): 437-47, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24604294

RESUMO

Although spiny rock lobster (Jasus edwardsii) is a wholly sub-littoral species, they show a considerable ability to survive prolonged emersion, a fact exploited during the commercial export of this species. Yet, despite this remarkable hardiness, basic information on how this species responds physiologically to emersion is somewhat lacking. Using flow-through respirometry and electrophysiological techniques, we identified that J. edwardsii undergoes marked physiological changes during rest, emersion and recovery over a broad range of temperatures (3.7-17.8 °C). Under resting conditions, routine metabolic rates (RMR) were 22.57 ± 2.39, 9.69 ± 0.55 and 8.09 ± 0.27 mL O2 h(-1), average heart rates (Hr) were 54.72 ± 4.46, 37.68 ± 2.86 and 29.67 ± 0.59 BPM, and ventilation frequencies were 83.71 ± 5.86, 45.34 ± 2.91 and 41.62 ± 0.65 BPM at 15.0, 7.5 and 3.7 °C, respectively. Notably, the surgical implantation of electrodes elevated RMR compared with non-surgical treatments. In surgery and non-surgery groups, Q 10 was calculated to be ca. 3.0. Upon emersion, rate of oxygen consumption and Hr decreased below resting rates in a temperature-dependent manner, but, along with rate of CO2 production, increased steadily during 24-h emersion. Ventilation frequencies upon emersion showed a contrasting response and increased significantly above resting rates. When returned to flow-through sea water for recovery, elevated respiration rates provided clear evidence of an O2 debt, and near-complete recovery was observed after 17 h at both 15.0 and 7.5 °C, but close to no debt was recovered at 3.7 °C. In addition, J. edwardsii was observed to undergo marked diurnal and periodic ventilation cycles, characterised by synchronous changes in RMR, Hr and ventilation frequency.


Assuntos
Palinuridae/fisiologia , Temperatura , Animais , Metabolismo Basal/fisiologia , Fenômenos Fisiológicos Cardiovasculares , Masculino , Recuperação de Função Fisiológica/fisiologia , Fenômenos Fisiológicos Respiratórios , Descanso/fisiologia
7.
J Exp Biol ; 216(Pt 3): 369-78, 2013 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-23038727

RESUMO

It was hypothesised that chronic hypoxia acclimation (preconditioning) would alter the behavioural low-O(2) avoidance strategy of fish as a result of both aerobic and anaerobic physiological adaptations. Avoidance and physiological responses of juvenile snapper (Pagrus auratus) were therefore investigated following a 6 week period of moderate hypoxia exposure (10.2-12.1 kPa P(O(2)), 21 ± 1 °C) and compared with those of normoxic controls (P(O(2))=20-21 kPa, 21 ± 1 °C). The critical oxygen pressure (P(crit)) limit of both groups was unchanged at ~7 kPa, as were standard, routine and maximum metabolic rates. However, hypoxia-acclimated fish showed increased tolerances to hypoxia in behavioural choice chambers by avoiding lower P(O(2)) levels (3.3 ± 0.7 vs 5.3 ± 1.1 kPa) without displaying greater perturbations of lactate or glucose. This behavioural change was associated with unexpected physiological adjustments. For example, a decrease in blood O(2) carrying capacity was observed after hypoxia acclimation. Also unexpected was an increase in whole-blood P(50) following acclimation to low O(2), perhaps facilitating Hb-O(2) off-loading to tissues. In addition, cardiac mitochondria measured in situ using permeabilised fibres showed improved O(2) uptake efficiencies. The proportion of the anaerobic enzyme lactate dehydrogenase, at least relative to the aerobic marker enzyme citrate synthase, also increased in heart and skeletal red muscle, indicating enhanced anaerobic potential, or in situ lactate metabolism, in these tissues. Overall, these data suggest that a prioritization of O(2) delivery and O(2) utilisation over O(2) uptake during long-term hypoxia may convey a significant survival benefit to snapper in terms of behavioural low-O(2) tolerance.


Assuntos
Oxigênio/metabolismo , Perciformes/fisiologia , Aclimatação , Animais , Hemoglobinas/metabolismo , Mitocôndrias/metabolismo , Mitocôndrias/ultraestrutura , Músculos/fisiologia , Oxigênio/sangue , Consumo de Oxigênio , Perciformes/sangue , Respiração
8.
Artigo em Inglês | MEDLINE | ID: mdl-22507523

RESUMO

It is already known that the New Zealand snapper (Pagrus auratus, Sparidae) does not avoid hypoxia until reaching an oxygen partial pressure (PO(2)) of 3.1±1.2 kPa at 18 °C. Avoidance at this level of PO(2) and temperature is below the critical oxygen partial pressure of the species (P(crit)=5.8±0.6 kPa, 43.5±4.5 mmHg) and is therefore expected to result in major physiological stress. Results from the current study showed that avoidance was associated with numerous physiological perturbations, including a significant endocrine response, haematological changes, osmoregulatory disturbance and metabolic adjustments in the heart, liver and muscle. Snapper clearly experienced physiological stress at the point of avoidance but they were not however in a state of physiological exhaustion since some fuel reserves were still available. In addition to avoidance, snapper also showed a subtle reduction in swimming speed - this energy-saving response may have helped snapper minimise the physiological challenge of low O(2) residence. It is therefore concluded that snapper can reside in water below their P(crit) threshold for brief periods of time and, without any evidence of physiological exhaustion at the point of avoidance, fish should recover quickly once normoxia is selected. Lastly, with signs of anaerobic metabolism in cardiac tissue at the point of avoidance, we tentatively suggest that snapper may leave hypoxia to protect heart function.


Assuntos
Comportamento Animal , Hipóxia , Perciformes/fisiologia , Animais , Metabolismo Basal , Glicemia , Glicogênio/metabolismo , Hematócrito , Hidrocortisona/sangue , Ácido Láctico/sangue , Ácido Láctico/metabolismo , Fígado/metabolismo , Músculos/metabolismo , Miocárdio/metabolismo , Consumo de Oxigênio , Perciformes/metabolismo , Natação
9.
J Exp Biol ; 214(Pt 17): 2927-34, 2011 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-21832136

RESUMO

The effect of altered oxygen transport potential on behavioural responses to environmental hypoxia was tested experimentally in snapper, Pagrus auratus, treated with a haemolytic agent (phenylhydrazine) or a sham protocol. Standard metabolic rate was not different between anaemic and normocythaemic snapper (Hct=6.7 and 25.7 g dl(-1), respectively), whereas maximum metabolic rate, and hence aerobic scope (AS), was consistently reduced in anaemic groups at all levels of water P(O(2)) investigated (P<0.01). This reduction of AS conferred a higher critical oxygen limit (P(crit)) to anaemic fish (8.6±0.6 kPa) compared with normocythaemic fish (5.3±0.4 kPa), thus demonstrating reduced hypoxic tolerance in anaemic groups. In behavioural choice experiments, the critical avoidance P(O(2)) in anaemic fish was 6.6±2.5 kPa compared with 2.9±0.5 kPa for controls (P<0.01). Behavioural avoidance was not associated with modulation of swimming speed. Despite differences in physiological and behavioural parameters, both groups avoided low P(O(2)) just below their P(crit), indicating that avoidance was triggered consistently when AS limits were reached and anaerobic metabolism was unavoidable. This was confirmed by high levels of plasma lactate in both treatments at the point of avoidance. This is the first experimental demonstration of avoidance behaviour being modulated by internal physiological state. From an ecological perspective, fish with disturbed oxygen delivery potential arising from anaemia, pollution or stress are likely to avoid environmental hypoxia at a higher P(O(2)) than normal fish.


Assuntos
Anemia/metabolismo , Hipóxia/metabolismo , Oxigênio/metabolismo , Perciformes/fisiologia , Anemia/induzido quimicamente , Animais , Aprendizagem da Esquiva , Comportamento Animal , Metabolismo Energético , Oxidantes , Fenil-Hidrazinas
10.
J Psychiatr Ment Health Nurs ; 9(4): 391-7, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12164900

RESUMO

This inquiry's purpose was to describe the meaning (essence) of moral perspective in adult women's experiences of anger expression. Moral perspectives have been perceived as pivotal to how one constructs and problem-solves real life dilemmas. Since some modes of anger expression have been identified as unhealthy, uncovering the meaning of moral perspectives in women's anger expression experiences could be significant to women's health. Through phenomenological interviews, 24 women, aged 21-65 (4 African-American and 20 Euro-American), reflected on an experience when they were angry and had to think about the right way to express their anger. Significant statements were extracted and thematized. Next, themes were clustered into the following essences of the experience: the realities of the self as moral, the morality of anger expression and the morality of outcomes.


Assuntos
Ira , Emoções Manifestas , Princípios Morais , Percepção , Mulheres/psicologia , Adulto , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Fatores Sexuais
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