2,498 research outputs found
Measurement of the derivative 'ZW' for an oscillating aerofoil
This report presents the results of experimental
measurements of the damping derivative coefficient zw for
constant chord rigid wings of various aspect ratios having
sweepback angles of zero and 450.
The results for the rectangular wings Flow substantial
agreement with the unsteady aerofoil theory developed
by TI.P. Jones $2) The dependence of Zvi upon frequency parameter
is as given by theory and is much less than for two dimensional
flow, but the numerical results are approximately
10 per cent below the theoretical. This is attributed to the
large trailing edge angle 22° of the N.A.C.A. 0020 section
used for the model aerofoils.
The effect of sweepback is to decrease the numerical
value of z , but this effect is much less pronounced, for low
than for high aspect ratios. For aspect ratios 5 and 3
the numerical value is greater than would be given by a factor
of proportionality equal to the cosine of the angle of
sweepback.
The measurements were corrected for tunnel interference
by a method based on the theoretical work of 7.P.Jones.(1
Comparison of physical activity metrics from two research-grade accelerometers worn on the non-dominant wrist and thigh in children
Beyond Justice, Beyond Peace? Colombia, the Interests of Justice, and the Limits of International Criminal Law
This paper explores the role of Article 53 of the Rome Statute and its âinterest of justiceâ standard in Colombia. After first providing some background to the ICCâs involvement in Colombia in the context of the so-called Justice and Peace Law and the more recent Legal Framework for Peace, we critically explore the reasons why the principle of complementarity is the focus of contemporary debates on the ICC in that country. We suggest that this discussion often ends in stalemate, with little space to move forward. In light of this, in this article we propose an alternative way to advance the discussion; namely, Article 53. We then consider whether, in order to protect transitional justice mechanisms adopted by states in order to end conflicts and move towards national reconciliation, the OTP has the power under Article 53(1)(c) to stop a prosecution on the basis that it is not in the interests of justice. Much here depends upon whether justice is interpreted broadly or narrowly. Two questions are central: First, should transitional justice arrangements be permissible under the legal framework established by the Rome Statute? Second, should the OTP concern itself with matters pertaining to domestic politics or should it understand its role as being completely independent from national processes? We advocate a narrow reading of the concept of justice, meaning that the OTP cannot use Article 53(1)(c) to prevent ICC intervention on the basis that it risks disrupting a transitional justice mechanism
Evidence for the Priming Effect in a Planktonic Estuarine Microbial Community
The âpriming effect,â in which addition of labile substances changes the remineralization rate of recalcitrant organic matter, has been intensively studied in soils, but is less well-documented in aquatic systems. We investigated the extent to which additions of nutrients or labile organic carbon could influence remineralization rates of 14C-labeled, microbially-degraded, phytoplankton-derived organic matter (OM) in microcosms inoculated with microbial communities drawn from Grove Creek Estuary in coastal Georgia, USA. We found that amendment with labile protein plus phosphorus increased remineralization rates of degraded, phytoplankton-derived OM by up to 100%, whereas acetate slightly decreased remineralization rates relative to an unamended control. Addition of ammonium and phosphate induced a smaller effect, whereas addition of ammonium alone had no effect. Counterintuitively, alkaline phosphatase activities increased in response to the addition of protein under P-replete conditions, indicating that production of enzymes unrelated to the labile priming compound may be a mechanism for the priming effect. The observed priming effect was transient: after 36 days of incubation roughly the same quantity of organic carbon had been mineralized in all treatments including no-addition controls. This timescale is on the order of the typical hydrologic residence times of well-flushed estuaries suggesting that priming in estuaries has the potential to influence whether OC is remineralized in situ or exported to the coastal ocean
Television and environmental sustainability: Arguing a case for a code of standards in NZ
This article explores the portrayal of the environment and environmental sustainability by free-to-air network television in New Zealand. The results are based on a three-month survey of a) the portrayal of the use and treatment of the environment, and b) the reporting of environmental news. While television includes environmentally-oriented programmes (eg. some BBC Horizon documentaries), there are no regular programmes about the state of the environment, sustainable use of resources and energy, and there is no regular environmental slot in the news in New Zealand. Some programmes and advertisements are environmentally unfriendly and a few trivialise resource abuse. It is argued that the media has an âorchestrationalâ influence on social norms and behaviours, and that to eliminate counter-messages requires the addition of a new âenvironmental standardâ to the Code of Broadcasting Practice. It is also argued that coverage of environmental news is quite narrow and, in the case of Television New Zealand, inconsistent with the stated aims of the Television Charter. New Zealand television could and should make a valuable contribution to environmental sustainability
Effect of a patient-information video on the preoperative anxiety levels of cataract surgery patients.
PURPOSE: To assess whether a cataract surgery patient-information video reduces patients' preoperative anxiety levels. SETTING: Leeds Teaching Hospitals NHS Trust, UK. DESIGN: Prospective controlled trial of an intervention to reduce anxiety for first-eye elective cataract surgery patients. METHODS: Patients attending for first-eye elective cataract surgery were included in the study. The primary outcome measure was a questionnaire based upon the Amsterdam Preoperative Anxiety and Information Score (APAIS), and an 80.0 mm visual analogue scale (VAS) score. The questionnaire was administered to a control group of consecutive preoperative cataract surgery patients who had not seen the information video. Subsequently, the video was introduced to the surgical pathway and the questionnaire was administered preoperatively to an intervention group of consecutive patients who had watched the video. RESULTS: The study comprised 200 patients (100 in the intervention group, 100 in the control group). There was a significant difference in mean VAS anxiety scores between the control group (45.5 mm ± 21.4 [SD]) and the intervention group (11.2 ± 11.4 mm) (P < .001). On a 5-stage Likert scale, responses to the APAIS statement "I am worried about the procedure" (range 1 = not at all to 5 = extremely worried) also showed that the control group patients were significantly more worried than the intervention group (P < .001). The mode response score was 3 in the control group versus 1 in the intervention group. CONCLUSIONS: Providing a patient-information video before cataract surgery was an inexpensive and effective intervention in reducing preoperative anxiety. Such interventions could improve the overall experience of cataract surgery patients
Improved estimates of 222 nm far-UVC susceptibility for aerosolized human coronavirus via a validated high-fidelity coupled radiation-CFD code.
Transmission of SARS-CoV-2 by aerosols has played a significant role in the rapid spread of COVID-19 across the globe. Indoor environments with inadequate ventilation pose a serious infection risk. Whilst vaccines suppress transmission, they are not 100% effective and the risk from variants and new viruses always remains. Consequently, many efforts have focused on ways to disinfect air. One such method involves use of minimally hazardous 222 nm far-UVC light. Whilst a small number of controlled experimental studies have been conducted, determining the efficacy of this approach is difficult because chamber or room geometry, and the air flow within them, influences both far-UVC illumination and aerosol dwell times. Fortunately, computational multiphysics modelling allows the inadequacy of dose-averaged assessment of viral inactivation to be overcome in these complex situations. This article presents the first validation of the WYVERN radiation-CFD code for far-UVC air-disinfection against survival fraction measurements, and the first measurement-informed modelling approach to estimating far-UVC susceptibility of viruses in air. As well as demonstrating the reliability of the code, at circa 70% higher, our findings indicate that aerosolized human coronaviruses are significantly more susceptible to far-UVC than previously thought
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