979 resultados para Temporary


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Introduction: Training for and competing in ultraendurance exercise events is associated with an improvement in endogenous antioxidant defenses as well as increased oxidative stress. However, consequences on health are currently unclear. Purpose: We aimed to examine the impact of training- and acute exercise-induced changes in the antioxidant capacity on the oxidant/antioxidant balance after an ironman triathlon and whether there are indications for sustained oxidative damage. Methods: Blood samples were taken from 42 well-trained male triathletes 2 d before an ironman triathlon, then immediately postrace, 1, 5, and 19 d later. Blood was analyzed for conjugated dienes (CD), malondialdehyde (MDA), oxidized low-density lipoprotein (oxLDL), oxLDL:LDL ratio, advanced oxidation protein products (AOPP), AOPP:total protein (TP) ratio, Trolox equivalent antioxidant capacity (TEAC), uric acid (UA) in plasma, and activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT) in erythrocytes. Results: Immediately postrace, there were significant increases in CD, AOPP, TEAC, UA (for all P < 0.001), and AOPP:TP (P < 0.01). MDA rose significantly (P < 0.01) 1 d postrace, whereas CD (P < 0.01), AOPP (P = 0.01), AOPP:TP (P < 0.05), and TEAC (P < 0.001) remained elevated. OxLDL:LDL trended to increase, whereas oxLDL significantly (P < 0.01) decreased 1 d postrace. Except for GSH-Px (P = 0.08), activities of SOD (P < 0.001) and CAT (P < 0.05) significantly decreased postrace. All oxidative stress markers had returned to prerace values 5 d postrace. Furthermore, several relationships between training status and oxidative stress markers, TEAC, and antioxidant enzyme activities were noted. Conclusions: This study indicates that despite a temporary increase in most (but not all) oxidative stress markers, there is no persistent oxidative stress in response to an ironman triathlon, probably due to training- and exercise-induced protective alterations in the antioxidant defense system.

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Also physical exercise in general is accepted to be protective, acute and strenuous exercise has been shown to induce oxidative stress. Enhanced formation of free radicals leads to oxidation of macromolecules and to DNA damage. On the other hand ultra-endurance events which require strenuous exercise are very popular and the number of participants is continuously increasing worldwide. Since only few data exists on Ironman triathletes, who are prototypes of ultra-endurance athletes, this study was aimed at assessing the risk of oxidative stress and DNA damage after finishing a triathlon and to predict a possible health risk. Blood samples of 42 male athletes were taken 2 days before, within 20 min after the race, 1, 5 and 19 days post-race. Oxidative stress marker increased only moderately after the race and returned to baseline after 5 days. Marker of DNA damage measured by the SCGE assay with and without restriction enzymes as well as by the sister chromatid exchange assay did either show no change or deceased within the first day after the race. Due to intake during the race and the release by the cells plasma concentrations of vitamin C and α-tocopherol increased after the event and returned to baseline 1 day after. This study indicates that despite a temporary increase in some oxidative stress markers, there is no persistent oxidative stress and no DNA damage in response to an Ironman triathlon in trained athletes, mainly due to an appropriate antioxidant intake and general protective alterations in the antioxidant defence system.

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Brain cells control everything we do - from speaking to walking to breathing. The brain needs a steady supply of blood and oxygen to function properly. Without this vital steady supply of blood, brain cells don't get enough nutrients and oxygen to do their job, and a stroke or 'brain attack' occurs. The human brain is divided into regions that control various motor (movement) and sensory (the senses) functions. Damage from stroke to a specific region may affect the functions it controls. This causes symptoms such as paralysis (loss of movement), difficulty speaking, or loss of coordination. The left side of the brain controls motor and sensory functions on the right side of the body. The left side is also responsible for scientific functions, understanding written and spoken language, number skills and reasoning. The right side of the brain controls motor and sensory functions on the left side of the body. It also controls artistic functions, such as music, art awareness, and insight. If an artery inside the brain or leading to the brain becomes temporarily blocked, the flow of blood to an area of the brain slows or stops. The lack of blood can cause temporary symptoms such as weakness, numbness, problems with speech, dizziness, or loss of vision.

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This paper presents a visual SLAM method for temporary satellite dropout navigation, here applied on fixed- wing aircraft. It is designed for flight altitudes beyond typical stereo ranges, but within the range of distance measurement sensors. The proposed visual SLAM method consists of a common localization step with monocular camera resectioning, and a mapping step which incorporates radar altimeter data for absolute scale estimation. With that, there will be no scale drift of the map and the estimated flight path. The method does not require simplifications like known landmarks and it is thus suitable for unknown and nearly arbitrary terrain. The method is tested with sensor datasets from a manned Cessna 172 aircraft. With 5% absolute scale error from radar measurements causing approximately 2-6% accumulation error over the flown distance, stable positioning is achieved over several minutes of flight time. The main limitations are flight altitudes above the radar range of 750 m where the monocular method will suffer from scale drift, and, depending on the flight speed, flights below 50 m where image processing gets difficult with a downwards-looking camera due to the high optical flow rates and the low image overlap.

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'Pars pro toto: Experimental Exhibition Design and Curatorial Paradigms' is situated within the ongoing debate over the conflation of art and curating, and the subsequent tension between artistic autonomy and curatorial intervention. This practice-led research project acclimates these polarities using a collaborative and discursive curatorial methodology in the creation of two exhibitions. Both exhibitions, one digital and one primarily physical, investigated how the temporary exhibition can operate as a site for provocation, how the suggested methodology facilitates the relationship between artist and curator within this paradigm, and outlines factors that assist in expanding the definition of the contemporary curatorial role.

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Purpose Traditional construction planning relies upon the critical path method (CPM) and bar charts. Both of these methods suffer from visualization and timing issues that could be addressed by 4D technology specifically geared to meet the needs of the construction industry. This paper proposed a new construction planning approach based on simulation by using a game engine. Design/methodology/approach A 4D automatic simulation tool was developed and a case study was carried out. The proposed tool was used to simulate and optimize the plans for the installation of a temporary platform for piling in a civil construction project in Hong Kong. The tool simulated the result of the construction process with three variables: 1) equipment, 2) site layout and 3) schedule. Through this, the construction team was able to repeatedly simulate a range of options. Findings The results indicate that the proposed approach can provide a user-friendly 4D simulation platform for the construction industry. The simulation can also identify the solution being sought by the construction team. The paper also identifies directions for further development of the 4D technology as an aid in construction planning and decision-making. Research limitations/implications The tests on the tool are limited to a single case study and further research is needed to test the use of game engines for construction planning in different construction projects to verify its effectiveness. Future research could also explore the use of alternative game engines and compare their performance and results. Originality/value The authors proposed the use of game engine to simulate the construction process based on resources, working space and construction schedule. The developed tool can be used by end-users without simulation experience.

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This study investigates friendships between gay sales associates and heterosexual female customers in luxury retail settings. By employing grounded theory methodology, the study integrates theories and findings from diverse literature streams into an original conceptual framework to illustrate the resources gay sales associates and straight female customers receive from and provide to each other during retail exchanges. The study explains why gay male–straight female friendships are uniquely suited for luxury consumption settings. Female customers characterize their friendships with gay sales associates as providing honesty, security, trust, and comfort, which stems from the absence of sexual interest and a lack of inter-female competition. Gay sales associates receive acceptance for who they are and for their displays of unconventional masculinity in retail settings. They also obtain a temporary rite from their female customers, a so-called mandate of privacy, which permits both parties to ignore the bounds of modesty and accept a degree of intimacy. Such intimacy facilitates transactions that require both personalization and customer–employee closeness, such as the selling of high-end apparel, accessories, and jewelry.

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In fisheries managed using individual transferable quotas (ITQs) it is generally assumed that quota markets are well-functioning, allowing quota to flow on either a temporary or permanent basis to those able to make best use of it. However, despite an increasing number of fisheries being managed under ITQs, empirical assessments of the quota markets that have actually evolved in these fisheries remain scarce. The Queensland Coral Reef Fin-Fish Fishery (CRFFF) on the Great Barrier Reef has been managed under a system of ITQs since 2004. Data on individual quota holdings and trades for the period 2004-2012 were used to assess the CRFFF quota market and its evolution through time. Network analysis was applied to assess market structure and the nature of lease-trading relationships. An assessment of market participants’ abilities to balance their quota accounts, i.e., gap analysis, provided insights into market functionality and how this may have changed in the period observed. Trends in ownership and trade were determined, and market participants were identified as belonging to one out of a set of seven generalized types. The emergence of groups such as investors and lease-dependent fishers is clear. In 2011-2012, 41% of coral trout quota was owned by participants that did not fish it, and 64% of total coral trout landings were made by fishers that owned only 10% of the quota. Quota brokers emerged whose influence on the market varied with the bioeconomic conditions of the fishery. Throughout the study period some quota was found to remain inactive, implying potential market inefficiencies. Contribution to this inactivity appeared asymmetrical, with most residing in the hands of smaller quota holders. The importance of transaction costs in the operation of the quota market and the inequalities that may result are discussed in light of these findings

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Driving can be a lonely activity. While there has been a lot of research and technical inventions concerning car-to-car communication and passenger entertainment, there is still little work concerning connecting drivers. Whereas tourism is very much a social activity, drive tourists and road trippers have few options to communicate with fellow travelers. Our study is placed at the intersection of tourism and driving. It aims to enhance the trip experience during driving through social interaction. This paper explores how a mobile application that allows instant messaging between travelers sharing similar context can establish a temporary, ad hoc community and enhance the road trip experience. A prototype was developed and evaluated in various user and field studies. The study’s outcomes are relevant for the design of future mobile tourist guides that benefit from community design, social encounters and recommendations.

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Background Informed consent is the legal requirement to educate a patient about a proposed medical treatment or procedure so that he or she can make informed decisions. The purpose of the study was to examine the current practice for obtaining informed consent for third molar tooth extractions (wisdom teeth) by Oral and Maxillofacial Surgeons in Australia and New Zealand. Methods An online survey was sent to 180 consultant Oral and Maxillofacial Surgeons in Australia and New Zealand. Surgeons were asked to answer (yes/no) whether they routinely warned of a specific risk of third molar tooth extraction in their written consent. Results 71 replies were received (39%). The only risks that surgeons agreed should be routinely included in written consent were a general warning of infection (not alveolar osteitis), inferior alveolar nerve damage (temporary and permanent) and lingual nerve damage (temporary and permanent). Conclusions There is significant variability among Australian and New Zealand Oral and Maxillofacial Surgeons regarding risk disclosure for third molar tooth extractions. We aim to improve consistency in consent for third molar extractions by developing an evidence-based consent form.

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Poor compliance with temporary speed limits is a common contributing factor in roadway work zone crashes. Despite the wide range of measures used to encourage compliance, speeding remains a major challenge in work zone traffic control. As part of the major study into safety at Queensland roadworks conducted by CARRS-Q and industry partners, an online survey was conducted to study the perceptions and experiences of drivers regarding roadworks, speed choice and related safety concerns. Survey participants (N=410) were asked to view photographs of 12 roadwork sites (shot from a drivers’ perspective without revealing the speed limits), to nominate the speed they thought they would drive at through work zones, and to rate from 1 to 5 separate levels of perceived risk to workers and to their own vehicles. The survey sought further information on topics including recall and effectiveness of public safety messages, perceived effectiveness of common roadwork safety measures, and demographic characteristics. Participants were also invited to express their concerns regarding any general or specific issue related to driving through roadworks. The current paper provides a descriptive summary of key findings from the survey, drawn from preliminary analyses of both quantitative and qualitative data, demonstrating the depth of data and its value for improving knowledge on driver perceptions and speed choice at roadworks. The survey is the first study of driver perceptions of roadwork risks and hazards to include an assessment of self-nominated speeds which can be compared with actual observed speeds at the same roadwork sites.

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The two articles that comprise this analysis springboard from the availability and increased popularity of the term genius to nineteenth and twentieth century educational scholars and its (temporary) location along a continuum of mindedness that was relatively new (i.e., as opposite to insanity). Three generations of analysis playfully structure the argument, taking form around the gen‐ root’s historical association with tropes of production and reproduction. Of particular interest in the analysis is how subject‐formation, including perceptions of non‐formation and elusivity, occurs. I examine this process of (non)formation within and across key texts on genius, especially in relation to their narrative structures, key binaries and sources of authority that collectively produce and embed specific cosmologies and their moral boundaries. The argument is staged across two articles that embody the three generations of analysis.

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This paper offers a rhizomatic reading of Foucault scholarship in anglophone educational research. It delineates unique parameters of an educational field, the conditions of receptivity for Foucault's work, and identifies three temporary plateau-formations that have erupted in educational research. Indebted to (non-formulaic) principles of connectivity and heterogeneity, multiplicity, and asignifying ruptures the analysis brings to notice the recombinatorial attributes of the discipline of education through attention to what is encamped and what seeps in debates over his work.

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Background Corneal oedema is a common post-operative problem that delays or prevents visual recovery from ocular surgery. Honey is a supersaturated solution of sugars with an acidic pH, high osmolarity and low water content. These characteristics inhibit the growth of micro-organisms, reduce oedema and promote epithelialisation. This clinical case series describes the use of a regulatory approved Leptospermum species honey ophthalmic product, in the management of post-operative corneal oedema and bullous keratopathy. Methods A retrospective review of 18 consecutive cases (30 eyes) with corneal oedema persisting beyond one month after single or multiple ocular surgical procedures (phacoemulsification cataract surgery and additional procedures) treated with Optimel Antibacterial Manuka Eye Drops twice to three times daily as an adjunctive therapy to conventional topical management with corticosteroid, aqueous suppressants, hypertonic sodium chloride five per cent, eyelid hygiene and artificial tears. Visual acuity and central corneal thickness were measured before and at the conclusion of Optimel treatment. Results A temporary reduction in corneal epithelial oedema lasting up to several hours was observed after the initial Optimel instillation and was associated with a reduction in central corneal thickness, resolution of epithelial microcysts, collapse of epithelial bullae, improved corneal clarity, improved visualisation of the intraocular structures and improved visual acuity. Additionally, with chronic use, reduction in punctate epitheliopathy, reduction in central corneal thickness and improvement in visual acuity were achieved. Temporary stinging after Optimel instillation was experienced. No adverse infectious or inflammatory events occurred during treatment with Optimel. Conclusions Optimel was a safe and effective adjunctive therapeutic strategy in the management of persistent post-operative corneal oedema and warrants further investigation in clinical trials.

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Background Guidelines and clinical practice for the prevention of complications associated with central venous catheters (CVC) around the world vary greatly. Most institutions recommend the use of heparin to prevent occlusion, however there is debate regarding the need for heparin and evidence to suggest 0.9% sodium chloride (normal saline) may be as effective. The use of heparin is not without risk, may be unnecessary and is also associated with increased cost. Objectives To assess the clinical effects (benefits and harms) of intermittent flushing of heparin versus normal saline to prevent occlusion in long term central venous catheters in infants and children. Search Methods The Cochrane Vascular Trials Search Co-ordinator searched the Specialised Register (last searched April 2015) and the Cochrane Register of Studies (Issue 3, 2015). We also searched the reference lists of retrieved trials. Selection criteria Randomised controlled trials that compared the efficacy of normal saline with heparin to prevent occlusion of long term CVCs in infants and children aged up to 18 years of age were included. We excluded temporary CVCs and peripherally inserted central catheters (PICC). Data Collection and Analysis Two review authors independently assessed trial inclusion criteria, trial quality and extracted data. Rate ratios were calculated for two outcome measures - occlusion of the CVC and central line-associated blood stream infection. Other outcome measures included duration of catheter placement, inability to withdraw blood from the catheter, use of urokinase or recombinant tissue plasminogen, incidence of removal or re-insertion of the catheter, or both, and other CVC-related complications such as dislocation of CVCs, other CVC site infections and thrombosis. Main Results Three trials with a total of 245 participants were included in this review. The three trials directly compared the use of normal saline and heparin, however, between studies, all used different protocols for the standard and experimental arms with different concentrations of heparin and different frequency of flushes reported. In addition, not all studies reported on all outcomes. The quality of the evidence ranged from low to very low because there was no blinding, heterogeneity and inconsistency between studies was high and the confidence intervals were wide. CVC occlusion was assessed in all three trials (243 participants). We were able to pool the results of two trials for the outcomes of CVC occlusion and CVC-associated blood stream infection. The estimated rate ratio for CVC occlusion per 1000 catheter days between the normal saline and heparin group was 0.75 (95% CI 0.10 to 5.51, two studies, 229 participants, very low quality evidence). The estimated rate ratio for CVC-associated blood stream infection was 1.48 (95% CI 0.24 to 9.37, two studies, 231 participants; low quality evidence). The duration of catheter placement was reported to be similar between the two study arms, in one study (203 participants). Authors' Conclusions The review found that there was not enough evidence to determine the effects of intermittent flushing of heparin versus normal saline to prevent occlusion in long term central venous catheters in infants and children. Ultimately, if this evidence were available, the development of evidenced-based clinical practice guidelines and consistency of practice would be facilitated.