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Hong Kong experiences year-round influenza activity with winter and summer peaks. The government's Vaccination Subsidy Scheme (VSS) provides vaccine to high-risk groups prior to the larger winter peak. The VSS is predominantly administered through the private sector. This study aimed to cost the two theoretical routine influenza vaccination schedules using both northern and southern hemisphere vaccines, administered according to child's age and women's gestation, from a governmental perspective; and compare these costs to the costs of government's seasonal VSS assuming equivalent coverage estimates to determine the budget impacts of these influenza vaccination programmes in Hong Kong. We used the World Health Organization's Flutool Plus to estimate the incremental annual costs for immunising young children aged 6 months to 2 years and pregnant women with influenza vaccine during 2021, assuming the latter group accesses the public system for some antenatal care. Inputs were based on literature review, publicly available data and expert opinions. Sensitivity analyses were done with various coverage rates and vaccine costs. The annual incremental cost (including vaccine price) to vaccinate young children with three doses of influenza vaccine during the first two years of life was estimated at USD 1,175,146 (per-dose-cost of USD 10.55) at 75% coverage while that to vaccinate pregnant women with one dose at 60% coverage was estimated at USD 398,555 (per-dose-cost of USD 13.39). Across a range of sensitivity analyses we predict that routine year-round schedules could be cost-saving to the government compared to the VSS. Implementing routine immunisation to both risk groups equates to USD 1,573,701, i.e., 0.012% of Hong Kong's annual healthcare spending. Proposed year-round universal schedules providing influenza immunisation according to the child's age or the woman's gestation are predicted to be cost-saving compared to the current seasonally administered subsidised vaccine programme. [ABSTRACT FROM AUTHOR]

In this research we demonstrate that a flexible ultra-thin supercapacitor can be fabricated using high volume screen printing process. This has enabled the sequential deposition of current collector, electrode, electrolyte materials and adhesive onto a Polyethylene terephthalate (PET) substrate in order to form flexible electrodes for reliable energy storage applications. The electrodes were based on an activated carbon ink and gel electrolyte each of which were formulated for this application. Supercapacitors that have surface areas from 100 to 1600 mm 2 and an assembled device thickness of 375 μm were demonstrated. The capacitance ranged from 50 to 400 mF. Capacitance of printed carbon electrodes is rarely reported in literature and no references were found. The chemistry developed during this study displayed long-term cycling potential and demonstrated the stability of the capacitor for continued usage. The gel electrolyte developed within this work showed comparable performance to that of a liquid counterpart. This improvement resulted in the reduction in gel resistance from 90Ω to 0.5Ω. Significant reduction was observed for all resistances. The solid-state supercapacitors with the gel electrolyte showed comparable performance to the supercapacitors that used a liquid electrolyte. This large area printed device can be used in future houses for reliable green energy storage. [ABSTRACT FROM AUTHOR]

The integrity of steel beam components in high intense stress applications have been observed to be influenced by the condition of the cut edge properties. The cut-edge characteristic properties formed during laser-cutting processing have been over prolonged periods determined to have beneficial effects on fatigue life. During this study two high strength steel grades S355MC and DP600 have been examined. This is important in the case of high strength steels, these were shown to display an increased sensitivity to fatigue cracks initiating from cut-edge regions. It was determined that by controlling the interrelationship between power and traverse cutting speed during the laser cutting process can result in optimised fatigue lives being achieved. Optimal fatigue lives were attained by minimising the laser cut-edge surface damage, maintaining the formation of shallow striations and by controlling the near edge microstructural deformations during each cutting process. This was validated using a bespoke automotive component in which was tested under four-point loading. [ABSTRACT FROM AUTHOR]

A novel, two-stage approach has been developed for producing the a priori spectrum for Bonner sphere unfolding in a case where neutrons are produced by spontaneous fission and (α,n) reactions, e.g. in UF 6 . The code SOURCES 4C is first used to obtain the energy spectrum of the neutrons inside the material, which is then fed into a MCNP model of the entire geometry to derive the neutron spectrum at the location of the Bonner sphere. Using this as the a priori spectrum produces a much more detailed unfolded Bonner sphere spectrum retaining fine structure from the calculation that would not be present if a simple estimated spectrum had been used as the a priori spectrum. This is illustrated using a Bonner sphere measurement of the neutron energy spectrum produced by a 48Y cylinder of UF 6 . From the unfolded spectrum an estimate has been made of the neutron ambient dose equivalent, i.e. the quantity which a neutron survey instrument should measure. The difference in the ambient dose equivalent of the unfolded spectrum is over 10% when using the novel approach instead of using a simpler estimate consisting of a single high energy peak, 1/E continuum, and thermal peak. [ABSTRACT FROM AUTHOR]

Abstract: In order to develop reference low-energy monoenergetic neutron fields, the 45Sc(p,n) reaction is being studied within the framework of a scientific cooperation between NPL, PTB, IRMM and IRSN. The first study is dedicated to the selection of the most suitable backing material for scandium targets. It must be able to sustain high proton beam currents to compensate for the low cross section of the 45Sc(p,n) reaction. Targets with backings made of Mo, Al, W, Ag, Pt and Ta were irradiated during several hours at a few tens of μA at the NPL neutron reference facility. Target thickness and composition were analysed with the RBS method at the AIFIRA facility before and after NPL irradiations leading to the selection of tantalum as the best choice for backing material. [ABSTRACT FROM AUTHOR]

Abstract: The reasons for measuring neutron spectra, and the locations where these measurements need to be made, are identified, and the underlying techniques used for making spectrometry measurements are discussed together with examples of various instruments. [ABSTRACT FROM AUTHOR]

Abstract: Objectives: This study determines the risk of ipsilateral ischaemic neurological events in relation to the degree of asymptomatic carotid stenosis and other risk factors. Methods: Patients (n=1115) with asymptomatic internal carotid artery (ICA) stenosis greater than 50% in relation to the bulb diameter were followed up for a period of 6–84 (mean 37.1) months. Stenosis was graded using duplex, and clinical and biochemical risk factors were recorded. Results: The relationship between ICA stenosis and event rate is linear when stenosis is expressed by the ECST method, but S-shaped if expressed by the NASCET method. In addition to the ECST grade of stenosis (RR 1.6; 95% CI 1.21–2.15), history of contralateral TIAs (RR 3.0; 95% CI 1.90–4.73) and creatinine in excess of 85μmol/L (RR 2.1; 95% CI 1.23–3.65) were independent risk predictors. The combination of these three risk factors can identify a high-risk group (7.3% annual event rate and 4.3% annual stroke rate) and a low risk group (2.3% annual event rate and 0.7% annual stroke rate). Conclusions: Linearity between ECST per cent stenosis and risk makes this method for grading stenosis more amenable to risk prediction without any transformation not only in clinical practice but also when multivariable analysis is to be used. Identification of additional risk factors provides a new approach to risk stratification and should help refine the indications for carotid endarterectomy. [Copyright &y& Elsevier]

Abstract: A EURAMET comparison exercise (#936) was hosted at NPL in 2008 with measurements being made by IRSN, NPL and PTB. The three laboratories have between them 3 types of long counter, two near identical commercial instruments, and two home-made instruments. Measurements were made using accelerator-produced monoenergetic fields of the following energies: 144 keV, 565 keV, 1.2 MeV, 5 MeV, and 17 MeV; and with the following radionuclide sources: 252Cf, 241Am-Be, 241Am-Li, 241Am-B, and 241Am-F. [ABSTRACT FROM AUTHOR]

ISO Standard 8529–1:2001 on Reference neutron radiations is under revision. The spectral data for the D 2 O-moderated 252Cf field in the 2001 version of the standard refer to calculations performed in the early 80s. There are changes in the revised standard, and these arise from updated calculations, described in this paper, based on a new 252Cf spectrum (from ENDF/B-VIII.0) and the MCNP6.2 transport code with ENDF/B-VIII.0 cross sections. In addition, the impact of different possible construction details of the D 2 O-moderated 252Cf assembly is provided. Lastly, in view of the need to perform irradiations of dosemeters on-phantom, the variation of spectrum and fluence across a 30 cm × 30 cm surface placed 100 cm from the source has been evaluated. • New spectra for 252Cf and D 2 O-moderated 252Cf to support ISO 8529–1:2001 revision. • Calculations based on ENDF/B-VIII.0 and the MCNP6.2 transport code. • Studied the impact of construction details of the D 2 O-moderated 252Cf assembly. • Proposed new values for conversion coefficients h ‾ ∗ (10) and h ‾ p (10,0) [ABSTRACT FROM AUTHOR]

Abstract: NPL, PTB, IRMM and IRSN are involved, within a scientific cooperation, in a comprehensive study aimed at developing reference low-energy monoenergetic neutron fields. This paper will explain the importance of such developments, highlighted by the over response of neutron survey meters in the keV energy range, and also describe the main difficulties encountered. The variation of the neutron yield with ion beam energy from the neutron threshold up to about 50 keV has been measured at IRSN AMANDE facility for the 45Sc(p,n), 65Cu(p,n), 51V(p,n), 57Fe(p,n) and 37Cl(p,n) reactions. [ABSTRACT FROM AUTHOR]

Abstract: Space weather phenomena can effect many areas of commercial airline operations including avionics, communications and GPS navigation systems. Of particular importance at present is the recently introduced EU legislation requiring the monitoring of aircrew radiation exposure, including any variations at aircraft altitudes due to solar activity. With the introduction of new ultra-long-haul “over-the-pole” routes, “more-electric” aircraft in the future, and the increasing use of satellites in the operation, the need for a better understanding of the space weather impacts on future airline operations becomes all the more compelling. This paper will present the various space weather effects, some provisional results of an ongoing 3-year study to monitor cosmic radiation in aircraft, and conclude by summarising some of the identified key operational issues, which must be addressed, with the help of the science community, if the airlines want to benefit from the availability of space weather services. [Copyright &y& Elsevier]

: ObjectivesTo determine the diagnostic accuracy of ureteroscopic biopsy and whether exfoliated cell cytology can improve diagnostic accuracy.: MethodsSixty-two cases of upper tract transitional cell carcinoma were diagnosed by ureteroscopic biopsy and treated by nephroureterectomy. Stage and grade evaluation was possible in 51 cases. Cytology for exfoliated cells from the ureter/pelvis was available in 48 cases.: ResultsBiopsies were staged as Tis in 3, Ta in 35, and T1 in 13 and graded as G1 in 6, G2 in 32, and G3 in 13. Cytology was positive/suspicious in 40% (19 of 48). The biopsy grade accurately predicted the pathologic grade (P <0.0001) and stage (P = 0.001). The biopsy stage was not associated with the final stage (P = 0.112, Fisher’s exact test). Biopsy G3 accurately predicted high-grade (G3) transitional cell carcinoma in 92% (12 of 13) of cases. The remaining 1 case was G2 by final histologic examination. No case of high-grade (G3) disease was found in the 6 G1 biopsies (100%). Of 32 G2 biopsies, 9 were upgraded to G3. Cytology was available for 8 of the 9 and 5 (63%) were positive. For patients with G2 biopsies, combining cytology and biopsy grade improved the sensitivity and specificity of high-grade tumor detection from 43% to 55% and 23% to 85%, respectively.: ConclusionsThe results of this study have shown that biopsy grade reflects the pathologic stage and grade. Combining exfoliated cell cytology improved the predictive power of biopsy G2 disease for high-risk specimen grade. Exfoliated cell cytology in combination with biopsy grade is recommended as part of the evaluation of upper tract transitional cell carcinoma selected for endoscopic management. [Copyright &y& Elsevier]

Several techniques based on laser induced fluorescence (LIF) spectrometry and laser enhanced ionization (LEI) spectrometry have been investigated for ultratrace measurements of arsenic. Studies by our group in this area that have been published previously are reviewed here, and are presented along with the results of recent studies that have not yet been published. The techniques presented include LIF detection in the inductively coupled plasma atomizer, the electrothermal atomizer, the tungsten coil atomizer, the flame atomizer and LEI detection in the flame atomizer, and include approaches that utilize hydride generation or laser ablation sample introduction. Recent efforts have been directed towards developing speciation approaches for arsenic that utilize LIF spectrometric detection. The capabilities of each technique are summarized including the sensitivity and limits of detection, which range from sub-pg ml−1 to ng ml−1 levels. Selected applications of the techniques are presented to demonstrate their utility for environmental and biological samples, and areas for future investigation and further development are discussed. [Copyright &y& Elsevier]