273 resultados para TESTING
Resumo:
We use a multiproxy palaeoecological dataset from Dead Island bog in Northern Ireland to examine the cause of the Sphagnum austinii (Sphagnum imbricatum) decline. The disappearance of this species from the peat record occurred just after the ‘AD 860’ tephra layer and is coeval with a rapid increase in bog surface wetness and increased mineral dust and charcoal abundance. Although it is difficult to identify one specific cause of the decline, the evidence for increased soil-derived dust is apparent and is supported by regional tephra-dated pollen diagrams that reveal extensive landscape changes due to agricultural intensification in early Medieval Ireland. As the decline of S. austinii occurred much later (~ AD 1860) in Fallahogy bog (~ 1.2 km away), we suggest that the decline of S. austinii at Dead Island was caused by a combination of fire and the deposition of soil-derived dust. We suggest that future studies should consider the use of multiple cores from each site to examine the within-site variability of the decline of S. austinii.
Resumo:
Analysis of colorectal carcinoma (CRC) tissue for KRAS codon 12 or 13 mutations to guide use of anti-epidermal growth factor receptor (EGFR) therapy is now considered mandatory in the UK. The scope of this practice has been recently extended because of data indicating that NRAS mutations and additional KRAS mutations also predict for poor response to anti-EGFR therapy. The following document provides guidance on RAS (i.e., KRAS and NRAS) testing of CRC tissue in the setting of personalised medicine within the UK and particularly within the NHS. This guidance covers issues related to case selection, preanalytical aspects, analysis and interpretation of such RAS testing.
Resumo:
We test current numerical implementations of laser-matter interactions by comparison with exact analytical results. Focusing on photon emission processes, it is found that the numerics accurately reproduce analytical emission spectra in all considered regimes, except for the harmonic structures often singled out as the most significant high-intensity (multiphoton) effects. We find that this discrepancy originates in the use of the locally constant field approximation.
Resumo:
There is interest in determining levels of Mycobacterium avium subsp. paratuberculosis (MAP) contamination in milk. The optimal sample preparation for raw cows' milk to ensure accurate enumeration of viable MAP by the peptide-mediated magnetic separation (PMS)-phage assay was determined. Results indicated that milk samples should be refrigerated at 4 C after collection and MAP testing should commence within 24 h, or samples can be frozen at 70 C for up to one month without loss of MAP viability. Use of Bronopol is not advised as MAP viability is affected. The vast majority (>95%) of MAP in raw milk sedimented to the pellet upon centrifugation at 2500 g for 15 min, so this milk fraction should be tested. De-clumping of MAP cells was most effectively achieved by ultrasonication of the resuspended milk pellet on ice in a sonicator bath at 37 kHz for 4 min in ‘Pulse’ mode.
Resumo:
Genuine Savings has emerged as a widely used indicator of sustainable development. In this paper, we use long -term data stretching back to 1870 to undertake empirical tests of the relationship between Genuine Savings (GS) and future well-being for three countries: Britain, the USA and Germany. Our tests are based on an underlying theoretical relationship between GS and changes in the present value of future consumption. Based on both single country and panel results, we find evidence supporting the existence of javascript:void(0);a cointegrating (long run equilibrium) relationship between GS and future well-being, and fail to reject the basic theoretical result on the relationship between these two macroeconomic variables. This provides some support for the GS measure of weak sustainability.
Testing the Stability of the Benefit Transfer function for Discrete choice Contingent Valuation Data
Resumo:
Recent research has shown that higher ambient turbulence leads to better wake recovery, so turbines could be installed in closer proximity in real tidal flows than might be assumed from typical towing tank tests that do not take into account turbulent inflow conditions. The standard tools to assess flow velocities in field conditions are Doppler based sonar devices, such as Acoustic Doppler Profilers (ADPs) or Acoustic Doppler Velocimeters (ADVs). The use of these devices poses some challenges when assessing the wake of a tidal turbine. While ADPs allow the three-dimensional measurement of a velocity profile over a distance, the data is calculated as a mean of three diverging beams and with low temporal resolution. ADVs can measure with higher sampling frequency but only at a single point in the flow. During the MaRINET testing of the SCHOTTELSIT turbine at the QUB tidal test site in Portaferry, Northern Ireland, ADP and ADV measurements were successfully tested.Two methods were employed for measuring the wake: firstly, with a rigidly mounted ADP and secondly, with a submerged ADV which was streamed behind the turbine. This paper presents the experimental set-up and results and discusses limitations and challenges of the two methods used.
Resumo:
Like any new technology, tidal power converters are being assessed for potential environmental impacts. Similar to wind power, where noise emissions have led to some regulations and limitations on consented installation sites, noise emissions of these new tidal devices attract considerable attention, especially due to the possible interaction with the marine fauna. However, the effect of turbine noise cannot be assessed as a stand-alone issue, but must be investigated in the context of the natural background noise in high flow environments. Noise measurements are also believed to be a useful tool for monitoring the operating conditions and health of equipment. While underwater noise measurements are not trivial to perform, this non-intrusive mon- itoring method could prove to be very cost effective. This paper presents sound measurements performed on the SCHOTTEL Instream Turbine as part of the MaRINET testing campaign at the QUB tidal test site in Portaferry during the summer of 2014. This paper demonstrates a comparison of the turbine noise emissions with the normal background noise at the test site and presents possible applications as a monitoring system.
Resumo:
Even though computational power used for structural analysis is ever increasing, there is still a fundamental need for testing in structural engineering, either for validation of complex numerical models or material behaviour. Many structural engineers/researchers are aware of cyclic and shake table test methods, but less so hybrid testing. Over the past 40 years, hybrid testing of engineering structures has developed from concept through to maturity to become a reliable and accurate dynamic testing technique. In particular, the application of hybrid testing as a seismic testing technique in recent years has increased notably. The hybrid test method provides users with some additional benefits that standard dynamic testing methods do not, and the method is much more cost effective in comparison to shake table testing. This paper aims to provide the reader with a basic understanding of the hybrid test method and its potential as a dynamic testing technique.
Resumo:
Policymakers have largely replaced Single Bounded Discrete Choice (SBDC) valuation by the more statistically efficient repetitive methods; Double Bounded Discrete Choice (DBDC) and Discrete Choice Experiments (DCE) . Repetitive valuation permits classification into rational preferences: (i) a priori well-formed; (ii) consistent non-arbitrary values “discovered” through repetition and experience; (Plott, 1996; List 2003) and irrational preferences; (iii) consistent but arbitrary values as “shaped” by preceding bid level (Tufano, 2010; Ariely et al., 2003) and (iv) inconsistent and arbitrary values. Policy valuations should demonstrate behaviorally rational preferences. We outline novel methods for testing this in DBDC applied to renewable energy premiums in Chile.