Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 10 de 10
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
2.
PLoS One ; 16(2): e0240952, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33606695

RESUMO

Intertidal systems are complex and dynamic environments with many interacting factors influencing biochemical characteristics and microbial communities. One key factor are the actions of resident fauna, many of which are regarded as ecosystem engineers because of their bioturbation, bioirrigation and sediment stabilising activities. The purpose of this investigation was to elucidate the evolutionary implications of the ecosystem engineering process by identifying, if any, aspects that act as selection pressures upon microbial communities. A mesocosm study was performed using the well characterised intertidal ecosystem engineers Corophium volutator, Hediste diversicolor, and microphytobenthos, in addition to manual turbation of sediments to compare effects of bioturbation, bioirrigation and stabilisation. A range of sediment functions and biogeochemical gradients were measured in conjunction with 16S rRNA sequencing and diatom taxonomy, with downstream bacterial metagenome function prediction, to identify selection pressures that incited change to microbial community composition and function. Bacterial communities were predominantly Proteobacteria, with the relative abundance of Bacteroidetes, Alphaproteobacteria and Verrucomicrobia being partially displaced by Deltaproteobacteria, Acidobacteria and Chloroflexi as dissolved oxygen concentration and redox potential decreased. Bacterial community composition was driven strongly by biogeochemistry; surface communities were affected by a combination of sediment functions and overlying water turbidity, and subsurface communities by biogeochemical gradients driven by sediment reworking. Diatom communities were dominated by Nitzschia laevis and Achnanthes sp., and assemblage composition was influenced by overlying water turbidity (manual or biogenic) rather than direct infaunal influences such as grazing.


Assuntos
Monitorização de Parâmetros Ecológicos/métodos , Estuários , Sedimentos Geológicos/microbiologia , Microbiota/genética , Acidobacteria/genética , Animais , Bactérias/genética , DNA Bacteriano/genética , Ecossistema , Microbiota/fisiologia , Filogenia , Poliquetos/genética , RNA Ribossômico 16S/genética , Escócia , Análise de Sequência de DNA/métodos , Microbiologia do Solo
3.
J Med Radiat Sci ; 67(4): 294-301, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32627421

RESUMO

INTRODUCTION: Deep inspiration breath hold (DIBH) has been proven to reduce cardiac dose for women receiving left breast and chest wall radiation therapy. However, it utilises extra departmental resources and patient exertion. The aim of this exploratory study was to investigate if any factors existed that could identify breast cancer patients who may benefit most from DIBH, to facilitate appropriate utilisation of departmental resources. METHODS: Left-sided breast cancer patients aged 18-70 years, and right-sided breast cancer patients with internal mammary nodes included, were recruited. DIBH and free breathing (FB) plans were created for all patients. Patient demographic and clinical history were recorded. Variables including lung threshold value, lung volume, patient separation, maximum heart in field, volume of planning target volume (PTV), heart dose, ipsilateral lung dose were compared between plans. RESULTS: Plans for 31 patients were analysed. No correlations were found between lung threshold value or patient separation and cardiac dose. Moderate to strong correlations were found with BMI, PTV volume and lung volume change however no definitive thresholds were determined. A significant difference was found in the maximum heart in field between DIBH and FB (P < 0.001) with those patients with greater than 0.7 cm heart in the field on the FB scan demonstrating greater reductions in mean heart dose. CONCLUSION: Maximum heart in the field of greater than 0.7 cm in FB could be a potential factor to identify patients who may benefit most from DIBH. This factor warrants investigation in a larger patient cohort to test its validity.


Assuntos
Neoplasias da Mama/radioterapia , Suspensão da Respiração , Inalação , Doses de Radiação , Feminino , Humanos , Radiometria , Dosagem Radioterapêutica
4.
Sci Rep ; 10(1): 3387, 2020 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-32099047

RESUMO

The extent to which commercially important Nephrops norvegicus lobsters feed on particulates in the wild is unknown, even though this could be an important way for burrow-dwelling females to avoid starvation during the long breeding season. This was investigated using δ13C and δ15N isotopic signatures in tissues with long and short turnover rates to provide diet discrimination and compare this between males and females. Secondary objectives examined size-related differences and calculated the trophic position based on the new results. Almost half the diet (47%) was made up of suspended particulate organic matter (POMsusp) alone. Fish was another important item in the diet, with plankton and invertebrate sources coming much lower down in dietary importance. Significantly more suspension feeding was observed in small or medium sized individuals than large ones in both sexes. However, there were no sex-related patterns, despite females being restricted to burrows for part of the analysis period. Female diet was almost identical to males and POMsusp comprised a large component of the diet in both sexes. The trophic position was estimated at 2.94 ± 0.16 (mean ± SD), which was at the lower end of the range reported in previous studies (2.60 to 4.32).


Assuntos
Dieta , Nephropidae/metabolismo , Material Particulado/metabolismo , Animais , Teorema de Bayes , Isótopos de Carbono/química , Isótopos de Carbono/metabolismo , Dieta/veterinária , Feminino , Masculino , Isótopos de Nitrogênio/química , Isótopos de Nitrogênio/metabolismo , Material Particulado/análise , Estações do Ano
5.
Paediatr Anaesth ; 30(4): 446-454, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31894609

RESUMO

BACKGROUND: Postoperative nausea and vomiting after elective outpatient surgery can complicate discharge and increase patient suffering. Within our hospital system, there was variability in the use of postoperative nausea and vomiting prophylaxis for patients undergoing anterior cruciate ligament reconstruction, which resulted in variable outcomes. To address this variability, we designed and implemented a standardized postoperative nausea and vomiting prophylaxis guideline for the care of this surgical population. AIM: We sought to develop and implement a standardized postoperative nausea and vomiting prophylaxis guideline for all patients presenting for elective ambulatory anterior cruciate ligament reconstruction with the goal of reducing the rate of emesis to ≤5%. METHODS: We convened a multidisciplinary team to develop a postoperative nausea and vomiting prophylaxis guideline which included administration of dexamethasone, ondansetron, and a low-dose propofol infusion in addition to a femoral and sciatic nerve block and routine ketorolac administration for pain control. Our primary outcome, emesis rate, was tracked using a P-chart. Process measures included use of guideline medications and balancing measures included opioid administration, pain scores, and emergence time. RESULTS: We analyzed postoperative nausea and vomiting outcomes for 817 patients from January 1, 2014, to December 31, 2018. The baseline postoperative emesis rate for all anesthetizing locations was 17%. Following, guideline implementation, the emesis rate decreased to 5%. Opioid administration was decreased following guideline implementation. The percentage of patients managed without any perioperative opioids increased from 16% in the baseline group to 38% following guideline implementation. The P-chart suggests that the observed reduction in emesis rate represents special cause variation and this reduction was sustained over a two-year period. CONCLUSIONS: Implementation of standard postoperative nausea and vomiting guidelines for adolescents undergoing outpatient anterior cruciate ligament reconstruction was associated with lower emesis rates. This reduction in emesis rate may have been due to the concurrent reduction in opioids we observed following guideline implementation.


Assuntos
Reconstrução do Ligamento Cruzado Anterior , Antieméticos/uso terapêutico , Dexametasona/uso terapêutico , Ondansetron/uso terapêutico , Náusea e Vômito Pós-Operatórios/tratamento farmacológico , Adolescente , Anti-Inflamatórios não Esteroides/uso terapêutico , Feminino , Humanos , Hipnóticos e Sedativos/uso terapêutico , Cetorolaco/uso terapêutico , Masculino , Bloqueio Nervoso/métodos , Propofol/uso terapêutico , Resultado do Tratamento
6.
Ambio ; 49(1): 107-117, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30852778

RESUMO

Stock enhancement activities provide an opportunity to examine density-dependent suppression of population biomass which is a fundamental issue for resource management and design of no-take-zones. We document 'catch-and-wait' fisheries enhancement where all but the largest lobsters are thrown back, recapturing them later after they have grown to a larger size. The residency, rate of return, and potential negative density-dependent effects of this activity are described using a combination of tagging and v-notching and by relating spatial growth patterns to population density defined with Catch Per Unit Effort. The results successfully demonstrated the concept of catch-and-wait practices. However, a density-dependent suppression of growth (in body size) was observed in male lobsters. This demonstrates a mechanism to explain differences in lobster sizes previously observed across EU fishing grounds with different stock densities. This negative effect of density could also affect individual biomass production in marine reserve or no-take zones.


Assuntos
Conservação dos Recursos Naturais , Pesqueiros , Biomassa , Peixes , Masculino , Densidade Demográfica
7.
Sci Data ; 6(1): 7, 2019 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-30914648

RESUMO

The availability of growth data in N. norvegicus is important for management purposes due to a lack of aging criteria and the commercial importance of fisheries in this species. Growth varies as a function of stock density, hence comparisons of growth rates between stocks at known density is particularly valuable. Growth is also related to starting size in males, making raw data on size-specific growth rates more valuable. Internally injected passive tags allowed us to track the growth of male and female individuals over one or two years. The spatial position of tagged recaptures was recorded to measure site fidelity of tagged releases. A total of 3300 pots were fished and their spatial positions were recorded to enable Catch Per Unit Effort calculations. Similarly, spatially geo-referenced v-notching and notched recovery enables spatially gridded densities to be calculated. Finally, acoustic mapping was carried out both on and off the fishing ground and was ground-truthed with sedimentology from grabs at 22 stations. These data are useful for fisheries and macroecological studies.


Assuntos
Pesqueiros , Nephropidae , Animais , Feminino , Masculino , Biologia Marinha , Dinâmica Populacional
8.
J Med Imaging Radiat Oncol ; 62(6): 854-860, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30175890

RESUMO

INTRODUCTION: Evidence that Deep Inspiration Breath Hold (DIBH) can reduce cardiac dose during left-sided breast radiation therapy (RT) has led to widespread uptake of this technology. There is a paucity of published information documenting the impact of this technique on the patient's treatment experience. The aim of this study was to develop a tool to assess the patient's experience with the introduction of DIBH using the Elekta® Active Breathing Coordinator (ABC) in a single institution. METHODS: A patient experience questionnaire was developed and was completed at three different stages of the patient's treatment; at planning, during the second week of treatment (day 6-10) and during the final week of treatment. RESULTS: Questionnaire data were collected from 30 patients, who underwent DIBH breast treatment during the period March 2016 to May 2017. Patients were very happy with their use of the ABC equipment and most felt they were well supported and informed during their treatment. Levels of general fatigue and personal anxiety were identified to significantly increase from planning to the conclusion of treatment (P = 0.002 and P < 0.001 respectively). CONCLUSIONS: This study produced a useful tool to measure patient experience during DIBH treatment. It demonstrated that the use of the technique was acceptable to patients and did not increase their distress. It provided a compelling case for the provision of tailored, well-communicated information, consistent routine and emotional support for patients throughout their entire treatment. The tool could be employed to assess the patient experience as new technologies are introduced into RT.


Assuntos
Suspensão da Respiração , Inquéritos e Questionários , Neoplasias Unilaterais da Mama/radioterapia , Feminino , Coração/efeitos da radiação , Humanos , Pessoa de Meia-Idade , Projetos Piloto , Estudos Prospectivos , Dosagem Radioterapêutica
9.
J Fish Biol ; 93(4): 685-693, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30069919

RESUMO

This study examines the diet of lesser spotted dogfish Scyliorhinus canicula, one of the most ubiquitous predators of European coastal waters. This species is of increasing ecological significance as other large predatory fish decline as it has known interactions with fisheries. Scyliorhinus canicula diet was investigated in Irish coastal waters during June and July 2014 using both stomach-content analysis and δ13 C and δ15 N stable-isotope ratios. Prey contribution to the diet from dual stable-isotope data was estimated using Bayesian mixing models. It was found that only stable-isotope analysis provided a time-integrated picture of the diet of S. canicula and allowed for a new estimation of their trophic position. Trophic positions from stomach-content analysis within the present study and previous studies were found to be higher than revealed by isotopes. Stomach-content analysis could not reveal the importance of soft-bodied animals in the diet of these fish, however this approach remains a valuable tool to understand the potential prey spectrum in advance of isotope analysis and allows for a better resolution down to species level. The results highlight a greater variety in the diet of this important predator and the benefit of taking a multidisciplinary approach in dietary studies.


Assuntos
Cação (Peixe)/fisiologia , Comportamento Alimentar , Animais , Teorema de Bayes , Isótopos de Carbono/análise , Dieta , Conteúdo Gastrointestinal/química , Isótopos de Nitrogênio/análise
10.
Sci Rep ; 6: 35143, 2016 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-27725735

RESUMO

Nephrops norvegicus is a commercially valuable fishery in the EU but management of stocks is challenging due to difficulties in aging individuals and calculating growth and biomass production. Growth of N. norvegicus was estimated by releasing 1177 tagged individuals in western Ireland in Summer 2013 and recapturing these in 2014 (n = 207, an average of 344 days later) and 2015 (n = 38, 654-665 days later). Moulting occurred twice per year in approximately half of the males and only once in females. Mean growth increments after approximately one year were 5.1 mm Carapace Length (CL) in males and 1.4 mm CL in females. After two years, males had grown by 12.0 mm CL and females by 4.6 mm CL, on average, across size classes. Low variation in growth increments was seen across female size classes, but significantly lower growth was observed in larger males, meeting an important assumption of the Von Bertalanffy Growth Function. Asymptotic carapace lengths were 70.8 mm (males) and 55.2 mm (females) with respective growth constants (k) of 0.161 yr-1 and 0.077 yr-1. The results suggest that this is a very productive fishery and that survivability of returns from creel fishing is high.


Assuntos
Muda , Nephropidae/crescimento & desenvolvimento , Exoesqueleto/crescimento & desenvolvimento , Animais , Aquicultura , Feminino , Irlanda , Masculino , Coloração e Rotulagem
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...