975 resultados para FAR-LATERAL APPROACH


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One of the aims of a broad ethnographic study into how the apportionment of risk influences pricing levels of contactors was to ascertain the significant risks affecting contractors in Ghana, and their impact on prices. To do this, in the context of contractors, the difference between expected and realized return on a project is the key dependent variable examined using documentary analyses and semi-structured interviews. Most work in this has focused on identifying and prioritising risks using relative importance indices generated from the analysis of questionnaire survey responses. However, this approach may be argued to constitute perceptions rather than direct measures of the project risk. Here, instead, project risk is investigated by examining two measures of the same quantity; one ‘before’ and one ‘after’ construction of a project has taken place. Risks events are identified by ascertaining the independent variables causing deviations between expected and actual rates of return. Risk impact is then measured by ascertaining additions or reductions to expected costs due to the occurrence of risk events. So far, data from eight substantially complete building projects indicates that consultants’ inefficiency, payment delays, subcontractor-related problems and changes in macroeconomic factors are significant risks affecting contractors in Ghana.

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We explore the potential for making statistical decadal predictions of sea surface temperatures (SSTs) in a perfect model analysis, with a focus on the Atlantic basin. Various statistical methods (Lagged correlations, Linear Inverse Modelling and Constructed Analogue) are found to have significant skill in predicting the internal variability of Atlantic SSTs for up to a decade ahead in control integrations of two different global climate models (GCMs), namely HadCM3 and HadGEM1. Statistical methods which consider non-local information tend to perform best, but which is the most successful statistical method depends on the region considered, GCM data used and prediction lead time. However, the Constructed Analogue method tends to have the highest skill at longer lead times. Importantly, the regions of greatest prediction skill can be very different to regions identified as potentially predictable from variance explained arguments. This finding suggests that significant local decadal variability is not necessarily a prerequisite for skillful decadal predictions, and that the statistical methods are capturing some of the dynamics of low-frequency SST evolution. In particular, using data from HadGEM1, significant skill at lead times of 6–10 years is found in the tropical North Atlantic, a region with relatively little decadal variability compared to interannual variability. This skill appears to come from reconstructing the SSTs in the far north Atlantic, suggesting that the more northern latitudes are optimal for SST observations to improve predictions. We additionally explore whether adding sub-surface temperature data improves these decadal statistical predictions, and find that, again, it depends on the region, prediction lead time and GCM data used. Overall, we argue that the estimated prediction skill motivates the further development of statistical decadal predictions of SSTs as a benchmark for current and future GCM-based decadal climate predictions.

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Nitrogen adsorption on carbon nanotubes is wide- ly studied because nitrogen adsorption isotherm measurement is a standard method applied for porosity characterization. A further reason is that carbon nanotubes are potential adsorbents for separation of nitrogen from oxygen in air. The study presented here describes the results of GCMC simulations of nitrogen (three site model) adsorption on single and multi walled closed nanotubes. The results obtained are described by a new adsorption isotherm model proposed in this study. The model can be treated as the tube analogue of the GAB isotherm taking into account the lateral adsorbate-adsorbate interactions. We show that the model describes the simulated data satisfactorily. Next this new approach is applied for a description of experimental data measured on different commercially available (and characterized using HRTEM) carbon nanotubes. We show that generally a quite good fit is observed and therefore it is suggested that the observed mechanism of adsorption in the studied materials is mainly determined by adsorption on tubes separated at large distances, so the tubes behave almost independently.

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The use of information and communication technologies (ICT) for transforming the way publicservices are delivered, has been an area of investment and focus in many countries in recentyears. The UK government envisioned moving from e-Government to transformationalgovernment by 2008, and initiatives such as the National Programme for IT (NPfIT) wereunderway towards this end. NPfIT was the largest civil IT programme worldwide at an initialestimated cost of £12.4bn over a ten-year period. It was launched in 2002 by the UKgovernment as part of its policy to transform the English NHS and to implement standardised ITsolutions at a national level. However, this top down, government led approach came underincreasing scrutiny, and is now being reconfigured towards a more decentralised mode of operations. This paper looks into the implementation of NPfIT and analyses the reasons behindits failure, and what effect the new NHS reforms are likely to have on the health sector. Wedraw from past studies (Weill and Ross, 2005) to highlight the key areas of concern in ITgovernance, using the NPfIT as an illustration

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In the absence of market frictions, the cost-of-carry model of stock index futures pricing predicts that returns on the underlying stock index and the associated stock index futures contract will be perfectly contemporaneously correlated. Evidence suggests, however, that this prediction is violated with clear evidence that the stock index futures market leads the stock market. It is argued that traditional tests, which assume that the underlying data generating process is constant, might be prone to overstate the lead-lag relationship. Using a new test for lead-lag relationships based on cross correlations and cross bicorrelations it is found that, contrary to results from using the traditional methodology, periods where the futures market leads the cash market are few and far between and when any lead-lag relationship is detected, it does not last long. Overall, the results are consistent with the prediction of the standard cost-of-carry model and market efficiency.

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The chapter examines how far medieval economic crises can be identified by analysing the residuals from a simultaneous equation model of the medieval English economy. High inflation, falls in gross domestic product and large intermittent changes in wage rates are all considered as potential indicators of crisis. Potential causal factors include bad harvests, wars and political instability. The chapter suggests that crises arose when a combination of different problems overwhelmed the capacity of government to address them. It may therefore be a mistake to look for a single cause of any crisis. The coincidence of separate problems is a more plausible explanation of many crises.

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In the 1980s, in the midst of the AIDS epidemic, many countries introduced lifetime bans on blood donations by men who had sexual relations with men (MSM). These blanket bans have, recently, begun to be challenged and, as a result, many countries have either relaxed them or completely abolished them. The case under examination (Léger ) is another instance of questioning the legality of such a ban. In particular, in this case, the European Court of Justice was called on to rule on whether a measure such as the French lifetime exclusion from blood donation of the MSM population that was at issue before the referring court is contrary to EU law. The Court ruled that although discriminatory on the ground of sexual orientation, such a ban may be justified in certain circumstances, and left it to the national court to make the final decision. This article seeks to analyse the case and to explain why, in the author’s view, the Court can be accused of—once more—not going far enough in the protection of lesbian, gay and bisexual (LGB) rights.

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Diverse invertebrate and vertebrate species live in association with plants of the large Neotropical family Bromeliaceae. Although previous studies have assumed that debris of associated organisms improves plant nutrition, so far little evidence supports this assumption. In this study we used isotopic ((15)N) and physiological methods to investigate if the treefrog Scinax hayii, which uses the tank epiphytic bromeliad Vriesea bituminosa as a diurnal shelter, contributes to host plant nutrition. In the field, bromeliads with frogs had higher stable N isotopic composition (delta(15)N) values than those without frogs. Similar results were obtained from a controlled greenhouse experiment. Linear mixing models showed that frog feces and dead termites used to simulate insects that eventually fall inside the bromeliad tank contributed, respectively, 27.7% (+/- 0.07 SE) and 49.6% (+/- 0.50 SE) of the total N of V. bituminosa. Net photosynthetic rate was higher in plants that received feces and termites than in controls; however, this effect was only detected in the rainy, but not in the dry season. These results demonstrate for the first time that vertebrates contribute to bromeliad nutrition, and that this benefit is seasonally restricted. Since amphibian-bromeliad associations occur in diverse habitats in South and Central America, this mechanism for deriving nutrients may be important in bromeliad systems throughout the Neotropics.

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Background: Endovascular procedures and direct surgical clipping, are the main therapeutic modalities for managing of BAAs. Furthermore, giant or wide-necked aneurysms and those that involve the PCA or perforators at its neck usually are not embolized. Case Description: A 55-year-old man presented to the emergency room complaining Of Sudden and intense headache. Neurological examination evidenced meningismus. Computed tomography disclosed a subarachnoid hemorrhage (Fisher grade III). Arteriograms revealed BAA, whose neck was partially obseured by the PCP. A standard pterional craniotomy was performed, followed. by extensive drilling of the greater sphenoid wing. The neck was partially hidden by the PCP, and no proximal control was obtained without drilling the PCP and opening the CS (modified TcA). Drilling of the PCP was begun by cutting the overlying dura and extended caudally as much as possible. Next. opening, of the roof of the CS was performed by incising the dura in the oculomotor trigone medical and parallel 10 the oculomotor nerve and lateral to ICA: the incision progressed posteriorly toward the dorsum sellae. Further resection of the dorsum sellac and clivus was carried out. After performing these steps, proximal control was obtained, aneurysm was deflated, perforators were saved. and aneurysm was clipped. Conclusions: This study has demonstrated the clinical Usefulness of and abbreviated form of the TcA, which led the ""modified TcA."" in approaching complex low-lying, BAA. It provides additional surgical room by removing the PCP and partially, opening the CS, which permits further bone removal and improves exposure. (C) 2009 Elsevier Inc. All rights reserved.

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Inledning: Studier påvisar att livsstilsrelaterade sjukdomar ständigt ökar och att fysisk inaktivitet bidrar till detta, likaså att FaR ej används i den utsträckning som det skulle behövas. Syfte: Att belysa för distriktssköterskor vilka underlättande och försvårande faktorer sjukvårdspersonal kan uppleva vid förskrivning av fysisk aktivitet på recept, FaR. Metod: En empirisk fenomenografisk intervjustudie med kvalitativ ansats. Fokusgruppsintervjuer med nio deltagare utfördes på tre vårdcentraler. Huvudresultat: Underlättande och försvårande faktorer framkom inom organisation samt i mötet mellan sjukvårdspersonal och patient, exempelvis stöd från cheferna, utbildning och motiverade patienter var underlättande faktorer. Försvårande faktorer var exempelvis tidsbrist, avsaknad av teamarbete samt negativ inställning till FaR. Konklusion: Chefernas engagemang samt patienternas inställning till fysisk aktivitet och FaR var områden som framkom vara av stor betydelse när sjukvårdspersonal skulle förskriva FaR. Att chefer gav sjukvårdspersonalen resurser för att möjliggöra arbetet med FaR, i form av tid, utbildning och teamarbete ansågs vara en grundläggande faktor. Hälsofrämjande synsätt och prioritering av FaR hos cheferna ger spridning och förankring hos sjukvårdspersonalen. Patienternas inställning till egenvård och fysisk aktivitet var en betydande faktor vid förskrivning av FaR. Där har distriktssköterskor en huvuduppgift i att motivera patienterna till livsstilsförändringar och egenvård samt informera om fysisk aktivitets inverkan på hälsan.

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The increased incidence of traumatic injuries to anterior teeth is a consequence of leisure activities, where the most common injuries are crown fractures. Treatment of the dental trauma is complex and requires a comprehensive and accurate diagnostic and treatment plan. It is also important to consider the biological, functional, esthetic and economic aspects, as well as the patient's desire. The purpose of this article is to report a case that shows the multidisciplinary approach required to successfully manage the rehabilitation of a maxillary central incisor with a complex crown fracture and a maxillary lateral incisor, that at first presented an oblique crown-root fracture, and after the orthodontic extrusion, suffered a more apical new crown-root fracture.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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This paper presents an economic design of (X) over bar control charts with variable sample sizes, variable sampling intervals, and variable control limits. The sample size n, the sampling interval h, and the control limit coefficient k vary between minimum and maximum values, tightening or relaxing the control. The control is relaxed when an (X) over bar value falls close to the target and is tightened when an (X) over bar value falls far from the target. A cost model is constructed that involves the cost of false alarms, the cost of finding and eliminating the assignable cause, the cost associated with production in an out-of-control state, and the cost of sampling and testing. The assumption of an exponential distribution to describe the length of time the process remains in control allows the application of the Markov chain approach for developing the cost function. A comprehensive study is performed to examine the economic advantages of varying the (X) over bar chart parameters.

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Objective To assess the brachial plexus block in chickens by an axillary approach and using a peripheral nerve stimulator.Study design Prospective, randomized, double-blinded study.Animals Six, 84-week old, female chickens.Methods Midazolam (1 mg kg(-1)) and butorphanol (1 mg kg(-1)) were administered into the pectoralis muscle. Fifteen minutes later, the birds were positioned in lateral recumbency and following palpation of the anatomic landmarks, a catheter was inserted using an axillary approach to the brachial plexus. Lidocaine or bupivacaine (1 mL kg(-1)) was injected after plexus localization by the nerve stimulator. Sensory function was tested before and after blockade (carpus, radius/ulna, humerus and pectoralis muscle) in the blocked and unblocked wings. The latency to onset of motor and sensory block and the duration of sensory block were recorded. A Friedman nonparametric one-way repeated-measures ANOVA was used to compare scores from baseline values over time and to compare the differences between wings at each time point.Results A total of 18 blocks were performed with a success rate of 66.6% (12/18). The latency for motor block was 2.8 +/- 1.1 and 3.2 +/- 0.4 minutes for lidocaine and bupivacaine, respectively. The latencies for and durations of the sensory block were 6.0 +/- 2.5 and 64.0 +/- 18.0 and 7.8 +/- 5.8 and 91.6 +/- 61.7 minutes for lidocaine and bupivacaine, respectively. There was no statistical difference between these times for lidocaine or bupivacaine. Sensory function was not abolished in nonblocked wings.Conclusions and clinical relevance The brachial plexus block was an easy technique to perform but had a high failure rate. It might be useful for providing anesthesia or postoperative analgesia of the wing in chickens and exotic avian species that have similar wing anatomy.

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Wavelets are being extensively used in Geodetic applications. In this paper, the Multi-Resolution Analysis (MRA) using wavelets is applied to pseudorange and carrier phase GPS double differences (DDs) in order to reduce multipath effects. The wavelets were already applied to GPS carrier phase DDs, but some questions remain: How good can be the results, and are all multipath effects reduced? The answers to these questions are discussed in this paper. Thus, the wavelet transform is used to decompose the DD signals, splitting them in lower resolution components. After the decomposition process, the wavelet shrinkage is performed by thresholding to eliminate the components relative to multipath effects. Then, the DD observation can be reconstructed. This new DD signal is used to perform the baseline processing. The daily multipath repeatability was verified. With the application of the proposed approach, the results showed that the reliability of the ambiguity resolution and accuracy of the results improved when compared with the standard procedure. Furthermore, the method showed to be very efficient computationally, because, it is not noticed, at practical level, difference in the time span between the processing with and without application of the proposed method. However, only the high frequency multipath was eliminated.