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An industry levy on sugar-sweetened beverages (SSB) was implemented in the UK in 2018. One year later, Brexit is likely to change the UK trade regime with potential implications for sugar price. We modelled the effect of potential changes in sugar price due to Brexit on SSB levy impacts upon CHD mortality and inequalities.
We modelled a baseline SSB levy scenario; an SSB levy under ‘soft’ Brexit, where the UK establishes a free trading agreement with the EU; and an SSB levy under ‘hard’ Brexit, in which World Trade Organization tariffs are applied. We used the previously validated IMPACT Food Policy model and probabilistic sensitivity analysis to estimate the effect of each scenario on CHD deaths prevented or postponed and life-years gained, stratified by age, sex and socio-economic circumstance, in 2021.
Adults aged 25 years or older.
The SSB levy was associated with approximately 370 (95 % uncertainty interval 220, 560) fewer CHD deaths and 4490 (2690, 6710) life-years gained in 2021. Associated reductions in CHD mortality were 4 and 8 % greater under ‘soft’ and ‘hard’ Brexit scenarios, respectively. The SSB levy was associated with approximately 110 (50, 190) fewer CHD deaths in the most deprived quintile compared with 60 (20, 100) in the most affluent, under ‘hard’ Brexit.
Our study found the SSB levy resilient to potential effects of Brexit upon sugar price. Even under ‘hard’ Brexit, the SSB levy would yield benefits for CHD mortality and inequalities. Brexit negotiations should deliver a fiscal and regulatory environment which promotes population health.
Survival into adult life in patients with aortic coarctation is typical following surgical and catheter-based techniques to relieve obstruction. Late sequelae are recognised, including stroke, hypertension, and intracerebral aneurysm formation, with the underlying mechanisms being unclear. We hypothesised that patients with a history of aortic coarctation may have abnormalities of cerebral blood flow compared with controls.
Patients with a history of aortic coarctation underwent assessment of cerebral vascular function. Vascular responsiveness of intracranial vessels to hypercapnia and degree of cerebral artery stiffness using Doppler-derived pulsatility indices were used. Response to photic stimuli was used to assess neurovascular coupling, which reflects endothelial function in response to neuronal activation. Patient results were compared with age- and sex-matched controls.
A total of 13 adult patients (males=10; 77%) along with 13 controls underwent evaluation. The mean age was 36.1±3.7 years in the patient group. Patients with a background of aortic coarctation were noted to have increased pulse pressure on blood pressure assessment at baseline with increased intracranial artery stiffness compared with controls. Patients with a history of aortic coarctation had less reactive cerebral vasculature to hypercapnic stimuli and impaired neurovascular coupling compared with controls.
Adult patients with aortic coarctation had increased intracranial artery stiffness compared with controls, in addition to cerebral vasculature showing less responsiveness to hypercapnic and photic stimuli. Further studies are required to assess the aetiology and consequences of these documented abnormalities in cerebral blood flow in terms of stroke risk, cerebral aneurysm formation, and cognitive dysfunction.
The effectiveness of leaf concentrate powder (LCP) as a nutritional supplement was established in trials conducted among adolescent girls and pregnant women in India. Here we evaluate LCP, compared with skimmed milk powder (SMP), as a supplement for antiretroviral-naïve children living with HIV in a sub-Saharan African country.
Randomized controlled, two-arm, 6-month trial comparing effects of isoproteic (5 g) LCP (10 g daily) and SMP (15 g daily) on HIV-1 viral load, CD4+ cell count/percentage, weight/height-for-age, general blood parameters, diarrhoea, respiratory and HIV-related opportunistic infections.
Bujumbura and Kirundo, Burundi.
Eighty-three HIV-positive, antiretroviral-naïve children aged 5–14 years: median (range) CD4+ count, 716 (361–1690) cells/mm3; log10 HIV-1 viral load, 4·39 (1·79–6·00).
LCP was equivalent to SMP in relation to HIV-specific blood parameters and did not demonstrate superiority over SMP in relation to Hb. Three children in each arm (LCP, 7·1 % (3/42); SMP, 7·3 % (3/41)) proceeded to antiretroviral therapy because their CD4+ counts fell below 350 cells/mm3. Children in the LCP group reported higher levels of appetite and overall health at 6 months. There were no differences in clinical events or any other outcome measures. LCP was less palatable than SMP to the children in this population, but there were few negative perceptions of appearance, texture and taste.
LCP appears to be equivalent to SMP as a nutritional supplement in this population, despite slightly lower palatability. In relation to viral load and CD4+ count, equivalence may indicate no effect in either group. Effectiveness relative to no supplementation remains to be determined.
Field studies were conducted in Alabama, Arkansas, Georgia, Louisiana, Mississippi, North Carolina, and Tennessee during 2010 and 2011 to determine the effect of glufosinate application rate on LibertyLink and WideStrike cotton. Glufosinate was applied in a single application (three-leaf cotton) or sequential application (three-leaf followed by eight-leaf cotton) at 0.6, 1.2, 1.8, and 2.4 kg ai ha−1. Glufosinate application rate did not affect visual injury or growth parameters measured in LibertyLink cotton. No differences in LibertyLink cotton yield were observed because of glufosinate application rate; however, LibertyLink cotton treated with glufosinate yielded slightly more cotton than the nontreated check. Visual estimates of injury to WideStrike cotton increased with each increase in glufosinate application rate. However, the injury was transient, and by 28 d after the eight-leaf application, no differences in injury were observed. WideStrike cotton growth was adversely affected during the growing season following glufosinate application at rates of 1.2 kg ha−1 and greater; however, cotton height and total nodes were unaffected by glufosinate application rate at the end of the season. WideStrike cotton maturity was delayed, and yields were reduced following glufosinate application at rates of 1.2 kg ha−1 and above. Fiber quality of LibertyLink and WideStrike cotton was unaffected by glufosinate application rate. These data indicate that glufosinate may be applied to WideStrike cotton at rates of 0.6 kg ha−1 without inhibiting cotton growth, development, or yield. Given the lack of injury or yield reduction following glufosinate application to LibertyLink cotton, these cultivars possess robust resistance to glufosinate. Growers are urged to be cautious when increasing glufosinate application rates to increase control of glyphosate-resistant Palmer amaranth in WideStrike cotton. However, glufosinate application rates may be increased to maximum labeled rates when making applications to LibertyLink cotton without fear of reducing cotton growth, development, or yield.
The whale shark Rhincodon typus is a popular focal species in the marine tourism industry. We analysed 689 encounters with at least 142 individual sharks during 2008–2010 to assess their behaviour in the presence of swimmers at Tofo Beach, Mozambique. Sharks varied in size (estimated 3.0–9.5 m total length) and the majority (74%) were males. The sharks displayed avoidance behaviours during 64.7% of encounters. Encounter duration decreased significantly, from 12 minutes 37 s with undisturbed sharks to 8 minutes 25 s when sharks expressed avoidance behaviours, indicating that interactions with tourists affected the sharks’ short-term behaviour. However, during the 2.5-year study period we found no trend in the mean encounter duration, the overall expression of avoidance behaviour or the likelihood of an individual shark exhibiting avoidance behaviours. Potential effects of tourism may be mitigated by the non-breeding status and transient behaviour of sharks at this aggregation site.
Archaeological and engineering work that took place in Westminster Hall in 2005–6 led to the discovery of further remains of the King's High Table, to add to those discovered in 1960. The Purbeck marble table stood at the south end of the hall from the thirteenth century to the seventeenth century and was the focus and symbol of English monarchy, serving particular roles in coronation feasts and in the development of the law courts. This paper suggests a reconstruction of the original table and its later extensions from the recovered fragments, and reviews the evidence for the construction, usage and destruction of the table in the context of the evolution of the hall and the palace, tracing its history through to its recent rediscovery and exhibition.
John Millington Synge (1871–1909) is the fulcrum upon which Irish drama and theatre studies is balanced. Synge's nodal position is predicated upon the dramatist's rock ‘n’ roll recalcitrance towards the dramaturgical praxis of his contemporaries; his subject matter was as shocking as the Anglo-Irish idiom in which it was articulated. After Synge's premature death in 1909, W. B. Yeats's fundamental concern was that Synge scholars would attempt ‘to mould . . . some simple image of the man’. However, W. J. McCormack's concentric biography of Synge, The Fool of the Family: A Life of J. M. Synge, and Ann Saddlemyer's The Collected Letters of John Millington Synge, have demonstrated that Synge's life was complex, multifaceted and in deep dialogue with Irish culture. But with respect to Synge's drama a simple image has surrounded critical discourse: the politics of Irish nationalism.
Spectroscopic ellipsometry (SE) analysis of so-called “specular” (macroscopically smooth) and “textured” (macroscopically rough) thin film amorphous silicon (a-Si:H) based solar cell structures demonstrates the need to incorporate interface layers into the multilayer stack in order to simulate the observed Stokes vector of the specularly-reflected beam. In most cases, these layers can be attributed to microscopic roughness (e.g., at the SnO2/p-layer/i-layer interface in a-Si:H p-i-n solar cells), as verified by atomic force microscopy (AFM). In limited cases, the layers may include regions wherein chemical intermixing also occurs (e.g., at the ZnO/Ag interface in back-reflectors), particularly for overlying films prepared by sputtering. In spite of the clear evidence for the existence of interface layers, they have been neglected in previous simulations of the optical quantum efficiency (QE) of the solar cells. In this study, we incorporate the experimentally- observed characteristics of interface layers as input into optical models for the p-i-n solar cell structure. In this way, we demonstrate the beneficial effects of SnO2/p/i interface microroughness as an anti-reflector and the detrimental effects of the ZnO/Ag interlayer as a parasitic absorber.
In this study, we optimize the plasma-enhanced chemical vapor deposition (PECVD) process to achieve high-density nucleation of single-phase microcrystalline silicon (µc-Si:H) p-type layers on zinc oxide (ZnO) surfaces at 200 °C for applications in amorphous silicon (a-Si:H) based p-i-n solar cells. The phase evolution of the Si:H p-layers on specular ZnO-coated glass substrates is characterized using real time spectroscopic ellipsometry (RTSE). The resulting evolutionary phase diagram depicts the accumulated film thickness at which the amorphous-to- microcrystalline (→µc) transition occurs versus the H2-dilution ratio, with all other parameters fixed. Guided by this diagram, we find that high-density microcrystallite nucleation and fully- coalesced µc-Si:H p-layers ∼100 Å thick can be obtained on specular ZnO at 200 Å using a B(CH3)3 doping gas flow ratio of D=[B(CH3)3]/[SiH4]=0.02 and an optimized H2-dilution ratio of R=[H2]/SiH4]=200. Lower H2-dilution levels (R<160) generate purely amorphous or mixed (a+µc) phases, and higher dilution levels (R>200) generate longer induction periods, low-density nucleation, and incomplete coalescence of microcrystallites even after ∼100 Å. The time evolution of the microstructure and the resulting dielectric functions as determined by RTSE are similar for optimized µc-Si:H p-layers ∼200 Å thick prepared on specular and textured ZnO surfaces, indicating that the substrate texturing does not necessitate process reoptimization.
The optical quantum efficiency and spectral response of p-i-n thin film amorphous silicon (a-Si:H) solar cells have been modeled using software based on optical admittance analysis. The optical constants of a-Si:H and Indium Tin Oxide (ITO) thin film layers have been measured by Variable Angle Spectroscopic Ellipsometry (VASE) and used as inputs into the optical admittance analysis program in order to model cells constructed from these films.
Amorphous silicon thin films and p-i-n assemblies have been deposited by glow discharge and reactive sputtering techniques. The optical constants of doped and intrinsic a-Si:H thin films were determined by VASE and the film thickness verified by Scanning Electron Microscopy studies. The optical constants of commercially available transparent conducting oxide (TCO) coated substrates have also been determined by VASE.
The experimental transmission spectra of p-i-n assemblies are compared with transmission spectra that have been modeled using the measured optical constants. Results of modeling different a-Si:H solar cell structures using these materials are presented, including a study of the optimal TCO layer thickness for p-i-n a-Si:H solar cells. This work shows that optical admittance modeling gives a good prediction of the optical behavior of p-i-n assemblies, but that accurate measurements of the optical constants of the component films are required in order to model effectively the optical quantum efficiency and photocurrent.
H/D-, N-H/D- and Si-H/D-bond density changes were investigated in stacks consisting of a Cz-Si substrate, a thin layer of SiO2, amorphous deuterated silicon nitride as well as amorphous hydrogenated silicon nitride in order to see if the post deposition anneal of a-SixNyHz layers on crystalline silicon wafers can actually lead to a migration of H atoms into the Si-bulk, which is an important question in regard to emitter passivation of Si-solar cells.
The stacks were grown with remote plasma enhanced chemical vapor deposition (RPECVD). A low temperature (≈200°C) process of down stream injected ammonia (NH3) and silane (SiH4) activated by an upstream injected He-plasma, produced through RF-radiation (13.65MHz) was used. Thermal treatment was executed by ex situ rapid thermal anneal in Ar ambient. For the measurements of H and D bond densities, FTIR was employed while SIMS determined atomic densities of H, D and O in the c-Si/nitride interface region. The experiments showed that H transport in silicon nitride is determined by several mechanisms including diffusion and dissociation processes and that silicon nitride deposited with high ammonia to silane ratios can produce molecular species like ammonia and H2. The study of the reaction dynamics showed that the production of molecular hydrogen is the most dominant process as long as Si-H-bonds are present in the system. After their exhaustion, an ammonia producing reaction prevails that leads with increasing temperatures to lower densities in the nitride films.
Amorphous hydrogenated silicon (a-Si:H) solar cells need efficient light trapping structures to achieve high efficiency. To this end, aluminum doped zinc oxide (ZnO:Al) as a transparent front contact was periodically structured. Solar cells with grating periods between 390 and 980 nm were realized. The structures were characterized by Atomic Force Microscopy (AFM) and optical reflection. A simple formula for the wavelength where total internal reflection starts is deduced for each diffraction order. Solar cells with a periodic grating show a significant reduction in the overall reflectance which is comparable to cells with an optimized statistical texture.