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PURPOSE: To develop and implement an acceptance procedure for the new Elekta Unity 1.5 T MRI-linac. METHODS: Tests were adopted and, where necessary adapted, from AAPM TG106 and TG142, IEC 60976 and NCS 9 and NCS 22 guidelines. Adaptations were necessary because of the atypical maximum field size (57.4 × 22 cm), FFF beam, the non-rotating collimator, the absence of a light field, the presence of the 1.5 T magnetic field, restricted access to equipment within the bore, fixed vertical and lateral table position, and the need for MR image to MV treatment alignment. The performance specifications were set for stereotactic body radiotherapy (SBRT). RESULTS: The new procedure was performed similarly to that of a conventional kilovoltage x-ray (kV) image guided radiation therapy (IGRT) linac. Results were acquired for the first Unity system. CONCLUSIONS: A comprehensive set of tests was developed, described and implemented for the MRI-linac. The MRI-linac met safety requirements for patients and operators. The system delivered radiation very accurately with, for example a gantry rotation locus of isocenter of radius 0.38 mm and an average MLC absolute positional error of 0.29 mm, consistent with use for SBRT. Specifications for clinical introduction were met.
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Planejamento da Radioterapia Assistida por Computador , Radioterapia Guiada por Imagem , Humanos , Imageamento por Ressonância Magnética , Aceleradores de Partículas , Imagens de Fantasmas , Dosagem RadioterapêuticaRESUMO
Measurements of pressure-sensitive paint (PSP) have been performed using new or non-scientific imaging technology based on machine vision tools. Machine vision camera systems are typically used for automated inspection or process monitoring. Such devices offer the benefits of lower cost and reduced size compared with typically scientific-grade cameras; however, their optical qualities and suitability have yet to be determined. This research intends to show relevant imaging characteristics and also show the applicability of such imaging technology for PSP. Details of camera performance are benchmarked and compared to standard scientific imaging equipment and subsequent PSP tests are conducted using a static calibration chamber. The findings demonstrate that machine vision technology can be used for PSP measurements, opening up the possibility of performing measurements on-board small-scale model such as those used for wind tunnel testing or measurements in confined spaces with limited optical access.
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In this study we test a novel approach to closing the anthropogenic nutrient cycle, by using the freshwater macroalga, Oedogonium intermedium, to recover dissolved nitrogen (N) and phosphorous (P) from municipal wastewater. We then convert this cultivated algae into two types of soil ameliorant; compost and biochar. To produce compost, algae was combined with sugarcane bagasse and left to mature for 10 weeks, and to produce biochar, algae was processed through slow pyrolysis at 450 °C. The mature compost had a total N and P content of 2.5% and 0.6%, which was 2- to 4-times lower than the algal biochar, which had a total N and P content of 5.5% and 2.5% respectively. Composting stabilized the N and P recovered from wastewater, with 80% of the initial N and >99% of the initial P retained in the mature compost. In contrast, only 29% of the initial N and 62% of the initial P was retained in the biochar. When the mature compost was added to a low fertility soil it significantly increased the production of sweet corn (Zea mays). Treatments receiving 50 and 100% compost produced 4-9 times more corn biomass than when synthetic fertilizer alone was added to the low fertility soil. When biochar was applied in conjunction with compost there was an additional 15% increase in corn productivity, most likely due to the ability of the biochar to bind labile N and P and prevent its loss from the soil. This study demonstrates a unique model for recovering N and P from municipal wastewater and recycling these nutrients into the agricultural industry. This could be an ideal model for regional areas where agriculture and water treatment facilities are co-located and could ultimately reduce the reliance of agriculture on finite mineral sources of P.
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Agricultura , Carvão Vegetal , Esgotos , SoloRESUMO
Green seaweeds from the genus Ulva are a promising feedstock for the production of biochar for carbon (C) sequestration and soil amelioration. Ulva can be cultivated in waste water from land-based aquaculture and Ulva blooms ("green tides") strand millions of tons of biomass on coastal areas of Europe and China each year. The conversion of Ulva into biochar could recycle C and nutrients from eutrophic water into agricultural production. We produce biochar from Ulva ohnoi, cultivated in waste water from an aquaculture facility, and characterize its suitability for C sequestration and soil amelioration through bio-chemical analyses and plant growth experiments. Two biomass pre-treatments (fresh water rinsing to reduce salt, and pelletisation to increase density) were crossed with four pyrolysis temperatures (300-750 °C). Biomass rinsing decreased the ash and increased the C content of the resulting biochar. However, biochar produced from un-rinsed biomass had a higher proportion of fixed C and a higher yield. C sequestration decreased with increasing pyrolysis temperatures due to the combination of lower yield and lower total C content of biochar produced at high temperatures. Biochar produced from un-rinsed biomass at 300 °C had the greatest gravimetric C sequestration (110-120 g stable C kg(-1) seaweed). Biochar produced from un-pelletised Ulva enhanced plant growth three-fold in low fertility soils when the temperature of pyrolysis was less than 450 °C. The reduced effectiveness of the high-temperature biochars (>450 °C) was due to a lower N and higher salt content. Soil ameliorated with biochar produced from pelletised biomass had suppressed plant germination and growth. The most effective biochar for C sequestration and soil amelioration was produced from un-rinsed and un-pelletised Ulva at 300 °C. The green tide that occurs annually along the Shandong coastline in China generates sufficient biomass (200,000 tons dry weight) to ameliorate 12,500 ha of soil, sequester 15,000 t C and recycle 5500 t N into agriculture. We provide clear parameters for biochar production to enable the beneficial use of this biomass.
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Carvão Vegetal , Temperatura , Ulva , Agricultura/métodos , Biomassa , Sequestro de Carbono , China , Europa (Continente) , Água Doce , Alga Marinha/química , Solo/química , Águas ResiduáriasRESUMO
Ash disposal waters from coal-fired power stations present a challenging water treatment scenario as they contain high concentrations of the oxyanions Se, As and Mo which are difficult to remove through conventional techniques. In an innovative process, macroalgae can be treated with Fe and processed through slow pyrolysis into Fe-biochar which has a high affinity for oxyanions. However, the effect of production conditions on the efficacy of Fe-biochar is poorly understood. We produced Fe-biochar from two algal sources; "Gracilaria waste" (organic remnants after agar is extracted from cultivated Gracilaria) and the freshwater macroalgae Oedogonium. Pyrolysis experiments tested the effects of the concentration of Fe(3+) in pre-treatment, and pyrolysis temperatures, on the efficacy of the Fe-biochar. The efficacy of Fe-biochar increased with increasing concentrations of Fe(3+) in the pre-treatment solutions, and decreased with increasing pyrolysis temperatures. The optimized Fe-biochar for each biomass was produced by treatment with a 12.5% w/v Fe(3+) solution, followed by slow pyrolysis at 300 °C. The Fe-biochar produced in this way had higher a biosorption capacity for As and Mo (62.5-80.7 and 67.4-78.5 mg g(-1) respectively) than Se (14.9-38.8 mg g(-1)) in single-element mock effluents, and the Fe-biochar produced from Oedogonium had a higher capacity for all elements than the Fe-biochar produced from Gracilaria waste. Regardless, the optimal Fe-biochars from both biomass sources were able to effectively treat Se, As and Mo simultaneously in an ash disposal effluent from a power station. The production of Fe-biochar from macroalgae is a promising technique for treatment of complex effluents containing oxyanions.
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Arsênio/química , Carvão Vegetal/química , Molibdênio/química , Selênio/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Biomassa , Clorófitas/química , Carvão Mineral , Cinza de Carvão/química , Água Doce , Gracilaria/química , Ferro/química , Alga Marinha/químicaRESUMO
Macroalgae are a productive resource that can be cultured in metal-contaminated waste water for bioremediation but there have been no demonstrations of this biotechnology integrated with industry. Coal-fired power production is a water-limited industry that requires novel approaches to waste water treatment and recycling. In this study, a freshwater macroalga (genus Oedogonium) was cultivated in contaminated ash water amended with flue gas (containing 20% CO2) at an Australian coal-fired power station. The continuous process of macroalgal growth and intracellular metal sequestration reduced the concentrations of all metals in the treated ash water. Predictive modelling shows that the power station could feasibly achieve zero discharge of most regulated metals (Al, As, Cd, Cr, Cu, Ni, and Zn) in waste water by using the ash water dam for bioremediation with algal cultivation ponds rather than storage of ash water. Slow pyrolysis of the cultivated algae immobilised the accumulated metals in a recalcitrant C-rich biochar. While the algal biochar had higher total metal concentrations than the algae feedstock, the biochar had very low concentrations of leachable metals and therefore has potential for use as an ameliorant for low-fertility soils. This study demonstrates a bioremediation technology at a large scale for a water-limited industry that could be implemented at new or existing power stations, or during the decommissioning of older power stations.
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Carvão Vegetal/análise , Clorófitas/química , Recuperação e Remediação Ambiental/métodos , Centrais Elétricas , Alga Marinha/química , Biodegradação Ambiental , Biomassa , Carvão Mineral , QueenslandRESUMO
In most countries the mining industry is required to rehabilitate disturbed land with native vegetation. A typical approach is to stockpile soils during mining and then use this soil to recreate landforms after mining. Soil that has been stockpiled for an extended period typically contains little or no organic matter and nutrient, making soil rehabilitation a slow and difficult process. Here, we take freshwater macroalgae (Oedogonium) cultivated in waste water at a coal-fired power station and use it as a feedstock for the production of biochar, then use this biochar to enhance the rehabilitation of two types of stockpiled soil - a ferrosol and a sodosol - from the adjacent coal mine. While the biomass had relatively high concentrations of some metals, due to its cultivation in waste water, the resulting biochar did not leach metals into the pore water of soil-biochar mixtures. The biochar did, however, contribute essential trace elements (particularly K) to soil pore water. The biochar had very strong positive effects on the establishment and growth of a native plant (Kangaroo grass, Themeda australis) in both of the soils. The addition of the algal biochar to both soils at 10 t ha(-1) reduced the time to germination by the grass and increased the growth and production of plant biomass. Somewhat surprisingly, there was no beneficial effect of a higher application rate (25 t ha(-1)) of the biochar in the ferrosol, which highlights the importance of matching biochar application rates to the requirements of different types of soil. Nevertheless, we demonstrate that algal biochar can be produced from biomass cultivated in waste water and used at low application rates to improve the rehabilitation of a variety of soils typical of coal mines. This novel process links biomass production in waste water to end use of the biomass in land rehabilitation, simultaneously addressing two environmental issues associated with coal-mining and processing.
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Carvão Vegetal/química , Mineração , Solo , Biomassa , Água Doce , Metais , Poaceae , Alga Marinha/química , Poluentes do Solo/análise , Oligoelementos , Águas ResiduáriasRESUMO
Macroalgae can be grown in industrial waste water to sequester metals and the resulting biomass used for biotechnological applications. We have previously cultivated the freshwater macroalga Oedogonium at a coal-fired power station to treat a metal-contaminated effluent from that facility. We then produced biochar from this biomass and determined the suitability of both the biomass and the biochar for soil amelioration. The dried biomass of Oedogonium cultivated in the waste water contained several elements for which there are terrestrial biosolids criteria (As, Cd, Cr, Cu, Pb, Ni, Se and Zn) and leached significant amounts of these elements into solution. Here, we demonstrate that these biomass leachates impair the germination and growth of radishes as a model crop. However, the biochar produced from this same biomass leaches negligible amounts of metal into solution and the leachates support high germination and growth of radishes. Biochar produced at 750 °C leaches the least metal and has the highest recalcitrant C content. When this biochar is added to a low-quality soil it improves the retention of nutrients (N, P, Ca, Mg, K and Mo) from fertilizer in the soil and the growth of radishes by 35-40%. Radishes grown in the soils amended with the biochar have equal or lower metal contents than radishes grown in soil without biochar, but much higher concentrations of essential trace elements (Mo) and macro nutrients (P, K, Ca and Mg). The cultivation of macroalgae is an effective waste water bioremediation technology that also produces biomass that can be used as a feedstock for conversion to biochar for soil amelioration.
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Carvão Vegetal/química , Metais Pesados/metabolismo , Alga Marinha/metabolismo , Poluentes do Solo/metabolismo , Purificação da Água/métodos , Biodegradação Ambiental , Biomassa , Produtos Agrícolas , Humanos , Resíduos Industriais , Águas ResiduáriasRESUMO
Selenium (Se) is a contaminant in effluents from coal mines and coal-fired power stations, where it is encountered as the oxyanion selenate (SeO4(2-), hereafter Se(VI)). Se(VI) can be removed from solution with Fe-treated biosorbents, but the efficacy of these treatments in effluents with multiple contaminants is unclear. This study investigates the interactions between Se(VI) and the oxyanions SO4(2-) and NO3(-). We produce a sustainable biosorbent, Gracilaria Modified Biochar (GMB), by treating a waste product generated after the commercial extraction of agar from cultivated seaweeds with ferric chloride (FeCl3) and converting it to biochar through pyrolysis. We then test interactions between Se(VI) and competing oxyanions in mock solutions and a real-world mine effluent with high concentrations of SO4(2-) and NO3(-). GMB immediately removed 98% of the Se(VI) from the mock solution, but only 3% from the mine effluent with the same initial Se(VI) concentration. Notably, 83-89% of the Se(VI) was removed by GMB when concentrations of Se(VI) and SO4(2-) were less than or equimolar in mock solutions. Higher concentrations of SO4(2-) reduced the uptake of Se(VI). There was no interference from NO3(-) on the biosorption of Se(VI). GMB is a successful biosorbent for Se(VI), however, high concentrations of SO4(2-) will compromise the biosorption of Se(VI).
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Resíduos Industriais/análise , Mineração , Ácido Selênico/química , Eliminação de Resíduos Líquidos/métodos , Adsorção , Carvão Vegetal , Cloretos , Carvão Mineral , Compostos FérricosRESUMO
Total occlusion of the abdominal aorta is a rare and life-threatening event. Risk factors most commonly include coagulopathy, vasculitis, trauma, abdominal aortic aneurysms, aortic thromboembolism, and aortic dissection. The most common complications include severe ischemic manifestations in the lower extremities, spinal cord, or viscera. Thus, management is largely dependent on presumed etiology. We present a case of a morbidly obese 52-year-old female with a past medical history of hypertension, diabetes mellitus, peripheral vascular disease, and coronary artery disease with a smoking history of three packs per day for over 10 years. The patient first presented to our emergency department with bilateral lower extremity paresthesia and pain at rest. Further evaluation through computed tomography angiogram thus revealed infrarenal occlusion of the abdominal aorta and bilateral common iliac arteries; the patient was treated with an aorto-femoral bypass without further sequelae. Our case report details the associated risk factors of acute on chronic aortic occlusion and its management.
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FOXA pioneer transcription factors (TFs) associate with primed enhancers in endodermal organ precursors. Using a human stem cell model of pancreas differentiation, we here discover that only a subset of pancreatic enhancers is FOXA-primed, whereas the majority is unprimed and engages FOXA upon lineage induction. Primed enhancers are enriched for signal-dependent TF motifs and harbor abundant and strong FOXA motifs. Unprimed enhancers harbor fewer, more degenerate FOXA motifs, and FOXA recruitment to unprimed but not primed enhancers requires pancreatic TFs. Strengthening FOXA motifs at an unprimed enhancer near NKX6.1 renders FOXA recruitment pancreatic TF-independent, induces priming, and broadens the NKX6.1 expression domain. We make analogous observations about FOXA binding during hepatic and lung development. Our findings suggest a dual role for FOXA in endodermal organ development: first, FOXA facilitates signal-dependent lineage initiation via enhancer priming, and second, FOXA enforces organ cell type-specific gene expression via indirect recruitment by lineage-specific TFs.
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Endoderma/embriologia , Elementos Facilitadores Genéticos/genética , Fator 3-alfa Nuclear de Hepatócito/metabolismo , Fator 3-beta Nuclear de Hepatócito/metabolismo , Sítios de Ligação , Diferenciação Celular , Células-Tronco Embrionárias/citologia , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Homeodomínio/genética , Humanos , Fígado/embriologia , Pulmão/embriologia , Motivos de Nucleotídeos , Especificidade de Órgãos , Organogênese , Pâncreas/embriologia , Transativadores/genéticaRESUMO
Over the last few years, magnetic resonance image-guided radiotherapy systems have been introduced into the clinic, allowing for daily online plan adaption. While quality assurance (QA) is similar to conventional radiotherapy systems, there is a need to introduce or modify measurement techniques. As yet, there is no consensus guidance on the QA equipment and test requirements for such systems. Therefore, this report provides an overview of QA equipment and techniques for mechanical, dosimetric, and imaging performance of such systems and recommendation of the QA procedures, particularly for a 1.5T MR-linac device. An overview of the system design and considerations for QA measurements, particularly the effect of the machine geometry and magnetic field on the radiation beam measurements is given. The effect of the magnetic field on measurement equipment and methods is reviewed to provide a foundation for interpreting measurement results and devising appropriate methods. And lastly, a consensus overview of recommended QA, appropriate methods, and tolerances is provided based on conventional QA protocols. The aim of this consensus work was to provide a foundation for QA protocols, comparative studies of system performance, and for future development of QA protocols and measurement methods.
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Garantia da Qualidade dos Cuidados de Saúde , Radioterapia Guiada por Imagem , Campos Magnéticos , Imageamento por Ressonância Magnética , Aceleradores de Partículas , Imagens de Fantasmas , Radiometria , Planejamento da Radioterapia Assistida por ComputadorRESUMO
Alveolar epithelial type II cells (AEC2s) are the facultative progenitors of lung alveoli and serve as the surfactant-producing cells of air-breathing organisms. Although primary human AEC2s are difficult to maintain stably in cell cultures, recent advances have facilitated the derivation of AEC2-like cells from human pluripotent stem cells (hPSCs) in vitro. Here, we provide a detailed protocol for the directed differentiation of hPSCs into self-renewing AEC2-like cells that can be maintained for up to 1 year in culture as epithelial-only spheres without the need for supporting mesenchymal feeder cells. The month-long protocol requires recapitulation of the sequence of milestones associated with in vivo development of the distal lung, beginning with differentiation of cells into anterior foregut endoderm, which is followed by their lineage specification into NKX2-1+ lung progenitors and then distal/alveolar differentiation to produce progeny that express transcripts and possess functional properties associated with AEC2s.
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Células Epiteliais Alveolares/citologia , Técnicas de Cultura de Células/métodos , Células-Tronco Pluripotentes/citologia , Células Epiteliais Alveolares/fisiologia , Animais , Diferenciação Celular , Linhagem Celular , Linhagem da Célula , Proliferação de Células , Autorrenovação Celular/genética , Autorrenovação Celular/fisiologia , Células Epiteliais/citologia , Células Alimentadoras , Humanos , Pulmão/citologia , Células-Tronco Pluripotentes/fisiologiaRESUMO
Epifaunal communities associated with macroalgae were exposed to storm water pulses using a custom made irrigation system. Treatments included Millipore freshwater, freshwater spiked with trace metals and seawater controls to allow for the relative importance of freshwater inundation, trace metals and increased flow to be determined. Experimental pulses created conditions similar to those that occur following real storm water events. Brief storm water pulses reduced the abundance of amphipods and gastropods. Freshwater was the causative agent as there were no additional effects of trace metals on the assemblages. Laboratory assays indicated that neither direct nor latent mortality was likely following experimental pulses and that epifauna readily avoid storm water. Indirect effects upon epifauna through salinity-induced changes to algal habitats were not found in field recolonisation experiments. Results demonstrate the importance of examining the effects of pulsed contaminants under realistic exposure conditions and the need to consider ecologically relevant endpoints.
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Anfípodes/fisiologia , Comportamento Animal/fisiologia , Ecossistema , Gastrópodes/fisiologia , Poluição da Água , Animais , Ecologia/métodos , Eucariotos , Água Doce , Água do Mar , Tempo (Meteorologia)RESUMO
Habitat-forming organisms are frequently used as biomonitors in marine environments due to a widespread ability to accumulate toxic contaminants. Few studies, however, have considered the consequences of these accumulated contaminants on the abundant and diverse fauna associated with these habitats. In this review, we summarize research which has investigated the contamination of biogenic habitats (including seagrasses, macroalgae, ascidians, sponges and bivalve reefs) and the impact of this contamination on the habitat use, feeding behaviour and survival of associated epifauna. In many cases, ecological impacts upon epifauna are not simply predicted by levels of contamination in their habitat, but are determined by the foraging, feeding and reproductive behaviours of the inhabiting organisms. Thus, a thorough understanding of these ecological processes is essential in order to understand the effects of contaminants upon epifaunal communities. The scope of biomonitoring studies which assess the contamination of biogenic habitats should be expanded to include an assessment of potential effects upon associated epifauna. When combined with manipulative field experiments such an approach would greatly assist in our understanding of indirect effects of contaminants in these important benthic habitats.
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Ecossistema , Plantas/efeitos dos fármacos , Poluentes Químicos da Água/efeitos adversos , Animais , Monitoramento Ambiental , Oceanos e MaresRESUMO
Dominance hierarchies are common across the animal kingdom and have important consequences for reproduction and survival. Animals of lower social status cope with repeated social defeat using proactive and reactive behaviours. However, there remains a paucity of information on how an individual's coping behaviours changes over time or what neural mechanisms are involved. We used a resident-intruder paradigm in the African cichlid fish Astatotilapia burtoni to investigate the neural correlates of these two opposing behaviour groups. Fish initially used both proactive and reactive behaviours, but had a dramatic increase in use of proactive behaviours during the third interaction, and this was followed by cessation of proactive behaviours and exclusive use of reactive coping. By quantifying neural activation in socially-relevant brain regions, we identify a subset of brain nuclei, including those homologous to the mammalian amygdala, showing higher activation in fish displaying proactive but not reactive behaviours. Fish displaying reactive behaviours had greater neural activation in the superior raphe, suggesting a possible conserved function during social defeat across vertebrates. These data provide the first evidence on the involvement of specific brain regions underlying proactive and reactive coping in fishes, indicating that these nuclei have conserved functions during social defeat across taxa.
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Adaptação Psicológica/fisiologia , Comportamento Animal/fisiologia , Ciclídeos/fisiologia , Dominação-Subordinação , Comportamento Social , Estresse Psicológico , Adaptação Fisiológica , Agressão , Tonsila do Cerebelo/metabolismo , Análise de Variância , Animais , Genes Precoces , Imuno-Histoquímica , Masculino , Núcleos da Rafe/metabolismo , Gravação em VídeoRESUMO
BACKGROUND: Assessment of function and functional interference is an important component of chronic pain assessment and treatment and is commonly based on self-report questionnaires. Existing questionnaires for assessing functional interference are language dependent, which can limit their utility for patients across cultures with literacy, fluency, or cognitive restrictions. OBJECTIVE: The objectives of this study were to create a tool with minimal language dependence and literacy requirement for measuring functional interference due to chronic pain and evaluate the psychometric properties and usability of this new assessment scale, the Pictorial Pain Interference Questionnaire (PPIQ), in a clinical sample of participants with chronic pain. DESIGN: The study employed a prospective, cross-sectional design in a clinical chronic pain setting. PARTICIPANTS AND METHODS: A total of 113 participants with chronic non-cancer pain were recruited from a private chronic pain clinic. A pictorial scale was developed and tested via psychometric procedures, including comparisons with validated measures of functional interference and related chronic pain constructs. RESULTS: Excellent internal consistency reliability (a=0.91), good construct validity (total score: r=0.72-0.81), and adequate-to-good convergent and discriminant validities were demonstrated through comparative analyses with existing self-report questionnaires. A scoring metric for classifying low, moderate, and high levels of interference was found to have good construct validity. Evaluation of satisfaction revealed adequate understanding of the PPIQ among most users. CONCLUSION: Initial support for the PPIQ as an alternative to language-based questionnaires for assessing functional interference from chronic pain was found. Subsequent research will help to clarify psychometric properties of the PPIQ and user response among various chronic pain subgroups.
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Whilst it has been well established that stormwater and associated contaminants negatively impact the quality of recipient waters, the ecological effects of individual stormwater pulses in marine environments are relatively unknown. In this study, the impacts of stormwater outfalls upon water quality and epifaunal invertebrates inhabiting the alga Sargassum linearifolium are assessed through an MBACI sampling program. Water quality and the abundance of mobile algal epifauna were recorded at three control sites and three impact sites every 10-12 weeks during dry weather and opportunistically within 24h of large rain events (>50 ml rainfall in 24h) and again 4d after the rain event. Sampling took place during two periods over two separate years and this included four large rainfall events. Following rainfall, salinity dropped rapidly at impact sites close to stormwater outfalls, whilst turbidity increased. Declines in salinity at control sites were slight and turbidity did not differ to 'before' periods. The abundance of epifaunal gastropods and polychaetes were reduced at impact sites 24h after rain events, but not control sites. The abundance of copepods, amphipods and ostracods, however, were reduced at both control and impact sites for up to 4d following rainfall. Reductions of these taxonomic groups could not be attributed to stormwater outfalls. Whilst short-term impacts of stormwater runoff were identified for some faunal groups, impacts were not identified for the majority. Instead, effects were harbour-wide (i.e. at control and impact sites), probably in response to the physical disturbance of heavy seas associated with large rain events.
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Biodiversidade , Monitoramento Ambiental/métodos , Chuva , Sargassum/fisiologia , Água/química , Anfípodes/fisiologia , Animais , Copépodes/fisiologia , Crustáceos/fisiologia , Gastrópodes/fisiologia , Poliquetos/fisiologia , Dinâmica Populacional , Poluição da Água/análiseRESUMO
Volume resuscitation to correct hypotension in surgical and critically ill patients is a common practice. Available evidence suggests that iatrogenic volume overload is associated with worse outcomes in established acute kidney injury. Intraoperative arterial hypotension is associated with postoperative renal dysfunction, and prompt correction with fluid management protocols that combine inotrope infusions with volume therapy targeted to indices of volume responsiveness should be considered. From the perspective of renal function, the minimum amount of intravenous fluid required to maintain perfusion and oxygen delivery is desirable. Available evidence and expert opinion suggest that balanced crystalloid solutions are preferable to isotonic saline for volume resuscitation. Moreover, albumin has a similar safety profile as crystalloids. Hetastarch-containing colloids have a clear association with acute kidney injury.
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Injúria Renal Aguda/etiologia , Hidratação/métodos , Ressuscitação/métodos , Injúria Renal Aguda/fisiopatologia , Albuminas/administração & dosagem , Albuminas/efeitos adversos , Animais , Coloides/administração & dosagem , Coloides/efeitos adversos , Cuidados Críticos/métodos , Estado Terminal/terapia , Soluções Cristaloides , Hidratação/efeitos adversos , Humanos , Derivados de Hidroxietil Amido/administração & dosagem , Derivados de Hidroxietil Amido/efeitos adversos , Soluções Isotônicas/administração & dosagem , Soluções Isotônicas/efeitos adversos , Ressuscitação/efeitos adversosRESUMO
Integration of reproduction and metabolism is necessary for species survival. While the neural circuits controlling energy homeostasis are well-characterized, the signals controlling the relay of nutritional information to the reproductive axis are less understood. The cichlid fish Astatotilapia burtoni is ideal for studying the neural regulation of feeding and reproduction because females cycle between a feeding gravid state and a period of forced starvation while they brood developing young inside their mouths. To test the hypothesis that candidate neuropeptide-containing neurons known to be involved in feeding and energy homeostasis in mammals show conserved distribution patterns, we performed immunohistochemistry and in situ hybridization to localize appetite-stimulating (neuropeptide Y, NPY; agouti-related protein, AGRP) and appetite-inhibiting (cocaine and amphetamine-regulated transcript, CART; pro-opiomelanocortin, pomc1a) neurons in the brain. NPY, AGRP, CART, and pomc1a somata showed distribution patterns similar to other teleosts, which included localization to the lateral tuberal nucleus (NLT), the putative homolog of the mammalian arcuate nucleus. Gravid females also had larger NPY and AGRP neurons in the NLT compared to brooding females, but brooding females had larger pomc1a neurons compared to gravid females. Hypothalamic agrp mRNA levels were also higher in gravid compared to brooding females. Thus, larger appetite-stimulating neurons (NPY, AGRP) likely promote feeding while females are gravid, while larger pomc1a neurons may act as a signal to inhibit food intake during mouth brooding. Collectively, our data suggest a potential role for NPY, AGRP, POMC, and CART in regulating energetic status in A. burtoni females during varying metabolic and reproductive demands.