989 resultados para Multimethod Probes


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Objective
Foot temperature has long been advocated as a reliable noninvasive measure of cardiac output despite equivocal evidence. The aim of this pilot study was to investigate the relationship between noninvasively measured skin temperature and the more invasive core-peripheral temperature gradients (CPTGs), against cardiac output, systemic vascular resistance, serum lactate, and base deficit.

Research methodology
The study was of a prospective, observational and correlational design. Seventy-six measurements were recorded on 10 adults postcardiac surgery. Haemodynamic assessments were made via bolus thermodilution. Skin temperature was measured objectively via adhesive probes, and subjectively using a three-point scale.

Setting
The study was conducted within a tertiary level intensive care unit.

Results
Cardiac output was a significant predictor for objectively measured skin temperature and CPTG (p = .001 and p = .004, respectively). Subjective assessment of skin temperature was significantly related to cardiac output, systemic vascular resistance, and serum lactate (p < .001, respectively).

Conclusions
These results support the utilisation of skin temperature as a noninvasive marker of cardiac output and perfusion. The use of CPTG was shown to be unnecessary, given the parallels in results with the less invasive skin temperature parameters. A larger study is however required to validate these findings.

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Using public remembrance of the controversial WWII firebombing of Dresden as its case study, the thesis probes the politics of war memory and commemoration. It argues that before, during, and after Germany's reunification, Dresden was portrayed as a, if not the, leading paradigm of German wartime loss and suffering.

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Silk is a structural protein fiber that is stable over a wide pH range making it attractive for use in medical and environmental applications. Variation in amino acid composition has the potential for selective binding for ions under varying conditions. Here we report on the metal ion separation potential of Mulberry and Eri silk fibers and powders over a range of pH. Highly sensitive radiotracer probes, 64Cu2+, 109Cd2+, and 57Co2+ were used to study the absorption of their respective stable metal ions Cu2+, Cd2+, and Co2+ into and from the silk sorbents. The total amount of each metal ion absorbed and time taken to reach equilibrium occurred in the following order: Cu2+ > Cd2+ > Co 2+. In all cases the silk powders absorbed metal ions faster than their respective silk fibers. Intensive degumming of the fibers and powders significantly reduced the time to absorb respective metal ions and the time to reach equilibrium was reduced from hours to 5-15 min at pH 8. Once bound, 45-100% of the metal ions were released from the sorbents after exposure to pH 3 buffer for 30 min. The transition metal ion loading capacity for the silk sorbents was considerably higher than that found for commercial ion exchange resins (AG MP-50 and AG 50W-X2) under similar conditions. Interestingly, total Cu2+ bound was found to be higher than theoretically predicted values based on known specific Cu2+ binding sites (AHGGYSGY), suggesting that additional (new) sites for transition metal ion binding sites are present in silk fibers.

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This article compares the classroom process of school teachers and university lecturers to the activity of theatrical performance. In doing so, it probes the potential of live performance as an educational instrument. It concludes by tracing some of the history of applications of theatre to education, from the time of Brecht to the present day.

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This critical review focuses on the development of anion sensors, being either fluorescent and/or colorimetric, based on the use of the 1,8-naphthalimide structure; a highly versatile building unit that absorbs and emits at long wavelengths. The review commences with a short description of the most commonly used design principles employed in chemosensors, followed by a discussion on the photophysical properties of the 4-amino-1,8-naphthalimide structure which has been most commonly employed in both cation and anion sensing to date. This is followed by a review of the current state of the art in naphthalimide-based anion sensing, where systems using ureas, thioureas and amides as hydrogen-bonding receptors, as well as charged receptors have been used for anion sensing in both organic and aqueous solutions, or within various polymeric networks, such as hydrogels. The review concludes with some current and future perspectives including the use of the naphthalimides for sensing small biomolecules, such as amino acids, as well as probes for incorporation and binding to proteins; and for the recognition/sensing of polyanions such as DNA, and their potential use as novel therapeutic and diagnostic agents (95 references).

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Human generated environmental problems are significant issues of global concern. Despite this, varying attitudes towards environments continue to exist across the globe, impacting on environmental decision-making and action at local, national and international levels. This paper probes some of the similarities and differences in environmental attitudes amongst pre-service teachers in Australia, Republic of Maldives and Indonesia. Data were collected using an established environmental attitude questionnaire and individual interviews. The three communities exhibited a similar range of environmental attitudes using the established questionnaire but significant differences emerged when the interview data were analysed phenomenographically. These differences reflect diversity within and across cultural groups that cannot be satisfactorily explained by the theory underpinning the established questionnaire. Consequently, a revised conceptual framework is proposed.

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Norman Brown, a coalminer engaged in picketing the Rothbury colliery, was shot dead by police in 1929. The Rothbury incident and the police suppression which followed became part of both union folklore and the personal legend of one police officer, William John MacKay, later New South Wales Police Commissioner. This article probes beneath the layers of myth that surround Rothbury and argues that the initial tragedy was largely the result of police incompetence, and that MacKay’s association with the shooting is deeply ironic. The more measured police actions that followed the shootings were Mackay’s responsibility, however, and they had damaging long-term consequences.

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We have identified a major allergenic protein from rye-grass pollen, tentatively designated Lol pIb of 31kDa and with pI 9.0. A cDNA clone encoding Lol pIb has been isolated, sequenced, and characterized. Lol pIb is located mainly in the starch granules. This is a distinct allergen from Lol pI, which is located in the cytosol. Lol pIb is synthesized in pollen as a pre-allergen with a transit peptide targeting the allergen to amyloplasts. Epitope mapping of the fusion protein localized the IgE binding determinant in the C-terminal domain.

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Nitric oxide is implicated in the pathogenesis of various neuropathologies characterized by oxidative stress. Although nitric oxide has been reported to be involved in the exacerbation of oxidative stress observed in several neuropathologies, existent data fail to provide a holistic description of how nitrergic pathobiology elicits neuronal injury. Here we provide a comprehensive description of mechanisms contributing to nitric oxide induced neuronal injury by global transcriptomic profiling. Microarray analyses were undertaken on RNA from murine primary cortical neurons treated with the nitric oxide generator DETA-NONOate (NOC-18, 0.5 mM) for 8–24 hrs. Biological pathway analysis focused upon 3672 gene probes which demonstrated at least a ±1.5-fold expression in a minimum of one out of three time-points and passed statistical analysis (one-way anova, P < 0.05). Numerous enriched processes potentially determining nitric oxide mediated neuronal injury were identified from the transcriptomic profile: cell death, developmental growth and survival, cell cycle, calcium ion homeostasis, endoplasmic reticulum stress, oxidative stress, mitochondrial homeostasis, ubiquitin-mediated proteolysis, and GSH and nitric oxide metabolism. Our detailed time-course study of nitric oxide induced neuronal injury allowed us to provide the first time a holistic description of the temporal sequence of cellular events contributing to nitrergic injury. These data form a foundation for the development of screening platforms and define targets for intervention in nitric oxide neuropathologies where nitric oxide mediated injury is causative.

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tRNA(3Lys) is a primer for reverse transcription in human immunodeficiency virus type 1 (HIV-1), and the anticodon of tRNA(3Lys) has been implicated in playing a role in both its placement onto the HIV-1 genome and its interaction with HIV-1 reverse transcriptase (RT). In this work, the anticodon in a tRNA(3Lys) gene was changed from UUU to CUA (tRNA(3Lys)Su+) or, in addition, G-73 was altered to A (tRNA(3Lys)Su+G73A). COS-7 cells were transfected with either wild-type or mutant tRNA(3Lys) genes, and both the wild-type and mutant tRNA(3Lys) produced were purified by using immobilized tRNA-specific hybridization probes. Each mutant tRNA(3Lys) was tested for its ability to prime reverse transcription in vitro, either alone or in competition with wild-type tRNA(3Lys). Short RT extensions of wild-type and mutant tRNALys could be distinguished from each other by their different mobilities in one-dimensional single-stranded conformation polymorphism polyacrylamide gel electrophoresis. These reverse transcription products show that heat-annealed tRNA(3Lys)Su+ has the same ability as heat-annealed wild-type tRNA(3Lys) to prime RT and competes equally well with wild-type tRNA(3Lys) for priming RT. tRNA(3Lys)Su+G73A has 60% of the wild-type ability to prime RT but competes poorly with wild-type tRNA(3Lys) for priming RT. However, the priming abilities of wild-type and mutant tRNA(3) are quite different when in vivo-placed tRNA is examined. HIV-1 produced in COS cells transfected with a plasmid containing both the HIV-1 proviral DNA and DNA coding for tRNA(3Lys)Su+ contains both endogenous, cellular wild-type tRNA(3Lys) and mutant tRNA(3Lys). When total viral RNA is used as the source of primer tRNA placed onto the genomic RNA in vivo, only wild-type tRNA(3Lys) is used as a primer. If the total viral RNA is first heated and exposed to hybridizing conditions, then both the wild-type and mutant tRNA(3Lys) act as primers for RT. These results indicate that the tRNA(3Lys)Su+ packaged into the virions is unable to act as a primer for RT, and a model is proposed to explain the disparate results between heat-annealed and in vivo-placed primer tRNA.

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Nonnucleoside reverse transcriptase inhibitors (NNRTIs) target HIV-1 reverse transcriptase (RT) by binding to a pocket in RT that is close to, but distinct, from the DNA polymerase active site and prevent the synthesis of viral cDNA. NNRTIs, in particular, those that are potent inhibitors of RT polymerase activity, can also act as chemical enhancers of the enzyme's inter-subunit interactions. However, the consequences of this chemical enhancement effect on HIV-1 replication are not understood. Here, we show that the potent NNRTIs efavirenz, TMC120, and TMC125, but not nevirapine or delavirdine, inhibit the late stages of HIV-1 replication. These potent NNRTIs enhanced the intracellular processing of Gag and Gag-Pol polyproteins, and this was associated with a decrease in viral particle production from HIV-1-transfected cells. The increased polyprotein processing is consistent with premature activation of the HIV-1 protease by NNRTI-enhanced Gag-Pol multimerization through the embedded RT sequence. These findings support the view that Gag-Pol multimerization is an important step in viral assembly and demonstrate that regulation of Gag-Pol/Gag-Pol interactions is a novel target for small molecule inhibitors of HIV-1 production. Furthermore, these drugs can serve as useful probes to further understand processes involved in HIV-1 particle assembly and maturation.

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 Ten years have passed since the US-led invasion of Iraq in 2003, and the political scene in Iraq is still blurry. Iraq was promoted to be the democratic example in the Middle East. The US came to Iraq to “create” a democratic system that can be a model for other countries in the region. A major factor in creating such environment is by changing the radical centralised totalitarian regime with a weak state that can give more space to building the civil society in new Iraq (Looney, 2003). Nonetheless, the socio-economic and political indicators of the newly installed political “democratic” system point to notable failures. Apart from poor socio-economic factors, the new political elite has either misused democracy for personal, ethno-sectarian or partisan gains or abused the system to ensure their long lasting presence in the decision making arena. Corruption, disconnection from electorate, poor performance and carelessness of politicians and failing state service provisions have all made citizens question the feasibility of political participation in elections. The electorate seem to have lesser faith in the political parties and blocs whose legitimacy of representation  is at stake. Noticeably, tribes have stepped forward to mobilise people as a non-partisan and independent powerful social structure. They have been active in lobbying the state as well as encouraging their members for active participation. This paper discusses the extent to which Iraqi tribes are involved in political participation. It explores their roles in active citizenship and the way they represent and mobilise their  members. It also probes whether tribes have the influence on shaping the political trajectory in Iraq.

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This paper re-examines the terrain of traditional communication time-based studies in the context of a case study of the communication practices of higher education students in both formal and informal contexts through an online survey and semi-structured phenomenologically focussed interviews. While focussing on the nature of students’ listening behaviour for learning and for leisure, the study explores how ideas and information are mediated in contemporary communication environments which encompass mobile devices, social media, etc. In exploring the nexus between the visual and the verbal, the research probes the ways in which contemporary higher education students navigate the increasingly complex communication environment and questions the capacity of current multiliteracies theories, for example, to engage meaningfully with this less charted terrain. The data suggests that the rapid and pervasive changes due to digital affordances have now positioned listening in a pivotal position alongside the explosive visual communication media. The capacity of our current curricula to respond creatively to the increasingly complex mix of new communication paradigms is open to question.

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Nest temperatures for green turtles (Chelonia mydas) nesting on Ascension Island, South Atlantic (7°57'S 14°22'W), were examined. Temperature probes were placed into nests on two beaches, Long Beach (26 nests) and North East Bay (8 nests). Within these beaches there was relatively little thermal variation (SD of nest temperature was 0.32°C for Long Beach and 0.30°C for North East Bay). To examine inter-beach thermal variation temperature probes were buried at 55 cm on 12 beaches. Inter-beach thermal variation was large and was related to the beach albedo with the darkest beach (albedo, 016) being 4.2°C warmer than the lightest coloured beach (albedo, 0.73).

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Localized corrosion can occur under disbonded coatings threatening the safe operation of industry infrastructures such as underground oil and gas pipelines. Currently the assessment of localised corrosion under coating defects is a major technical challenge. The application of corrosion probes to monitor corrosion under disbonded coating also remains a difficulty. This paper presents a new corrosion sensor concept capable of electrochemically measuring corrosion rates under disbonded coatings on cathodically protected structures such as energy pipelines. Examples of its capabilities are illustrated with experimental data obtained in low conductivity aqueous solutions.