Climate Change, Grape Phenology and Frost Risk in Southeast England

Background and Aims: Cultivation of grapevines in England is expected to benefit under climate change. Yet assessments of future wine-climates remain undeveloped. Accordingly, this study assesses how climate change might modify frost risk for Chardonnay in the Southeast England viticulture region. Methods and Results: Cold-bias corrected climate projections from the UKCP18 Regional (12 km) perturbed parameter ensemble (PPE) climate model under RCP8.5 are applied with phenological models to determine how frost risk and the timing of key grapevine phenophases might alter under climate change. Notwithstanding the uncertainties associated with projections of key viticulture related bioclimate variables, last spring frost is found to advance at a greater rate than budbreak indicating a general decrease in frost risk. Conclusions: Although projections point to an improving climate for viticulture across Southeast England frost will remain a risk for viticulture albeit at a reduced level compared to the present. Further the strong cold-bias found for temperature simulations used in this study needs to be given careful consideration when using the UKCP18 projections for climate change viticulture impact assessments. Significance of the Study: This study highlights the present sensitivity of viticulture to climate variability and the inherent uncertainty associated with making future projections of wine-climate under climate change

Biological Equivalence of GGTA-1 Glycosyltransferase Knockout and Standard Porcine Pericardial Tissue Using 90-Day Mitral Valve Implantation in Adolescent Sheep

Objective There is growing interest in the application of genetically engineered reduced antigenicity animal tissue for manufacture of bioprosthetic heart valves (BHVs) to reduce antibody induced tissue calcification and accelerated structural valve degeneration (SVD). This study tested biological equivalence of valves made from Gal-knockout (GalKO) and standard porcine pericardium after 90-day mitral valve implantation in sheep. Methods GalKO (n = 5) and standard (n = 5) porcine pericardial BHVs were implanted in a randomized and blind fashion into sheep for 90-days. Valve haemodynamic function was measured at 30-day intervals. After explantation, valves were examined for pannus, vegetation, inflammation, thrombus, and tissue calcification. Results Nine of 10 recipients completed the study. There was no difference between study groups for haemodynamic performance and no adverse valve-related events. Explanted BHVs showed mild pannus integration and minimal thrombus, with no difference between the groups. Limited focal mineral deposits were detected by x-ray. Atomic spectroscopy analysis detected tissue calcium levels of 1.0 µg/mg ± 0.2 for GalKO BHVs and 1.9 µg/mg ± 0.9 for standard tissue BHVs (p = 0.4), considered to be both low and equivalent. Conclusions This is the first demonstration of biological equivalence between GalKO and standard pig pericardium. The GalKO mutation causes neither intrinsic detrimental biological nor functional impact on BHV performance. Commercial adaptation of GalKO tissue for surgical or transcatheter BHVs would remove the clinical disparity between patients producing anti-Gal antibody and BHVs containing the Gal antigen. GalKO BHVs may reduce accelerated tissue calcification and SVD, enhancing patient choices, especially for younger patients

Measuring Active-Sterile Neutrino Oscillations with a Stopped Pion Neutrino Source

The question of the existence of light sterile neutrinos is of great interest in many areas of particle physics, astrophysics, and cosmology. Furthermore, should the MiniBooNE experiment at Fermilab confirm the LSND oscillation signal, then new measurements are required to identify the mechanism responsible for these oscillations. Possibilities include sterile neutrinos, CP or CPT violation, variable mass neutrinos, Lorentz violation, and extra dimensions. In this paper, we consider an experiment at a stopped pion neutrino source to determine if active-sterile neutrino oscillations with delta-m greater than 0.1 eV2 can account for the signal. By exploiting stopped pi+ decay to produce a monoenergetic nu_mu source, and measuring the rate of the neutral current reaction nu_x + 12C -> nu_x +12C* as a function of distance from the source, we show that a convincing test for active-sterile neutrino oscillations can be performed.Comment: 10 pages, 9 figure

B4GALNT2 and xenotransplantation: A newly appreciated xenogeneic antigen

Analysis of non-Gal antibody induced after pig-to-baboon cardiac xenotransplantation identified the glycan produced by porcine beta-1,4-N-acetyl-galactosaminyltransferase 2 (B4GALNT2) as an immunogenic xenotransplantation antigen. The porcine B4GALNT2 enzyme is homologous to the human enzyme, which synthesizes the human SDa blood group antigen. Most humans produce low levels of anti-SDa IgM which polyagglutinates red blood cells from rare individuals with high levels of SDa expression. The SDa glycan is also present on GM2 gangliosides. Clinical GM2 vaccination studies for melanoma patients suggest that a human antibody response to SDa can be induced. Expression of porcine B4GALNT2 in human HEK293 cells results in increased binding of anti-SDa antibody and increased binding of Dolichos biflorus agglutinin (DBA), a lectin commonly used to detect SDa. In pigs, B4GALNT2 is expressed by vascular endothelial cells and endothelial cells from a wide variety of pig backgrounds stain with DBA, suggesting that porcine vascular expression of B4GALNT2 is not polymorphic. Mutations in B4GALNT2 have been engineered in mice and pigs. In both species, the B4GALNT2-KO animals are apparently normal and no longer show evidence of SDa antigen expression. Pig tissues with a mutation in B4GALNT2, added to a background of alpha-1,3-galactosyltransferase deficient (GGTA1-KO) and cytidine monophosphate-N-acetylneuraminic acid hydroxylase deficient (CMAH-KO), show reduced antibody binding, confirming the presence of B4GALNT2-dependent antibodies in both humans and non-human primates. Preclinical xenotransplantation using B4GALNT2-deficient donors has recently been reported. Elimination of this source of immunogenic pig antigen should minimize acute injury by preformed anti-pig antibody and eliminate an induced clinical immune response to this newly appreciated xenotransplantation antigen

Physical equivalency of wild type and Galactose α 1,3 Galactose free porcine pericardium; a new source material for bioprosthetic heart valves

Humans make high levels of antibody to carbohydrates with terminal galactose α 1,3 galactose (Gal) modifications. This Gal antigen is widely expressed in other mammals and is present on an array of current animal derived biomedical devices including bioprosthetic heart valves. There is growing interest in using Gal-free animal tissues from Gal knockout pigs (GTKO) as these tissues would not be affected by anti-Gal antibody mediated injury. In this study we compare the composition and biophysical characteristics of glutaraldehyde fixed porcine pericardium from standard and GTKO pigs. We show that with the exception of the Gal antigen which is only present in standard pig tissue both GTKO and standard pig tissue have the same general morphology and collagen content. Moreover uniaxial stress testing and suture retention testing indicate the tissues are equivalent in tensile strength. These studies indicate that genetic disruption of the α-galactosyltransferase (GGTA-1) which blocks synthesis of the Gal antigen has no significant impact on the structural integrity of porcine pericardium and suggest that this tissue could be directly substituted for standard pig pericardium in biomedical devices such as bioprosthetic heart valves. STATEMENT OF SIGNIFICANCE: Surgical heart valve replacement is a proven life saving therapy to treat heart valve dysfunction due to birth defects, infection and the effects of aging. Bioprosthetic heart valves (BHV) made from glutaraldehyde fixed animal tissues are an effective durable therapy in older patients (> 60 years) but exhibit age-dependent structural valve degeneration (SVD) in younger patients (<60 years). SVD is principally caused by BHV calcification. Immune injury contributes to age-dependent SVD through the interaction of galactose α 1,3 galactose (Gal) a dominant xenogeneic antigen present on commercial BHVs and universally abundant human anti-Gal antibody. This study measures the tissue equivalency between standard pig pericardium and Gal-free pericardium from genetically modified pigs as a first step towards making Gal-free BHVs

The extent of public green space and alien plant species in 10 small towns of the sub-tropical Thicket Biome, South Africa

Urban areas in developing countries will accommodate nearly 90% of the projected world population increase between 1995 and 2030. Despite this, few studies, especially in smaller towns, have been carried out on urban green space areas in the developing world. This paper makes a first step in this regard, reporting on the extent and state of urban green spaces within 10 small towns in the Eastern Cape (South Africa). After measuring the size and state (in terms of woody plant cover) of public green space, we then sought patterns across the 10 towns between green space attributes, such as area, density, mean size and proportion of alien or indigenous, with socio-economic attributes of the towns. The area and state of current public green space varied markedly between the towns, with the poorer towns faring the worst. Lower income levels were significantly negatively correlated with the area and quality of public green space. Despite this, human population density and per capita green space were the best predictors of the proportion and mean area of public green space present in the towns. The proportion of town green space and the per capita green space were the best predictors of changes in woody plant composition and density

L-band (3.5 micron) IR-excess in massive star formation, II. RCW 57/NGC 3576

We present a JHKL survey of the massive star forming region RCW 57 (NGC 3576) based on L-band data at 3.5 micron taken with SPIREX (South Pole Infrared Explorer), and 2MASS JHK data at 1.25-2.2 micron. This is the second of two papers, the first one concerning a similar JHKL survey of 30 Doradus. Colour-colour and colour-magnitude diagrams are used to detect sources with infrared excess. This excess emission is interpreted as coming from circumstellar disks, and hence gives the cluster disk fraction (CDF). Based on the CDF and the age of RCW 57, it is possible to draw conclusions on the formation and early evolution of massive stars. The infrared excess is detected by comparing the locations of sources in JHKL colour-colour and L vs. (K-L) colour-magnitude diagrams to the reddening band due to interstellar extinction. A total of 251 sources were detected. More than 50% of the 209 sources included in the diagrams have an infrared excess. Comparison with other JHKL surveys, including the results on 30 Doradus from the first paper, support a very high initial disk fraction (>80%) even for massive stars, although there is an indication of a possible faster evolution of circumstellar disks around high mass stars. 33 sources only found in the L-band indicate the presence of heavily embedded, massive Class I protostars. We also report the detection of diffuse PAHs emission throughout the RCW 57 region.Comment: 15 pages, 13 figure

Technique for producing highly planar Si/SiO0.64Ge0.36/Si metal–oxide–semiconductor field effect transistor channels

Si/Si0.64Ge0.36/Si heterostructures have been grown at low temperature (450 °C) to avoid the strain-induced roughening observed for growth temperatures of 550 °C and above. The electrical properties of these structures are poor, and thought to be associated with grown-in point defects as indicated in positron annihilation spectroscopy. However, after an in situ annealing procedure (800 °C for 30 min) the electrical properties dramatically improve, giving an optimum 4 K mobility of 2500 cm2 V – 1 s – 1 for a sheet density of 6.2 × 1011 cm – 2. The low temperature growth yields highly planar interfaces, which are maintained after anneal as evidenced from transmission electron microscopy. This and secondary ion mass spectroscopy measurements demonstrate that the metastably strained alloy layer can endure the in situ anneal procedure necessary for enhanced electrical properties. Further studies have shown that the layers can also withstand a 120 min thermal oxidation at 800 °C, commensurate with metal–oxide–semiconductor device fabrication

UCL Qualitative health research symposium 2017: collaboration in qualitative health research

In recent years, there have been increasing calls for collaboration between academia and the wider healthcare community in health research. This is largely driven by efforts to engage the public in the “co-production” of evidence-based healthcare and healthcare decision-making, as well as penetrate borders between disciplines. As a result, traditional "lone researcher" models of qualitative health research have shifted to include research teams which are increasingly made up of qualitative researchers alongside quantitative researchers, members of the public, health professionals, policy-makers and other stakeholders. In these ways, health research is assumed to be more relevant, ethically justifiable, and broadly applicable. However, such collaborations may be complex and may create challenges. To date, there has been limited critical consideration of these challenges and little is known about the assumptions and effectiveness of these collaborations. We organised a one-day symposium to explore themes related to engagement, co-production and collaborative meaning making in qualitative health research. The oral presentations and posters used examples of collaborative studies to critically explore the processes used to carry out research as a diverse team. The discussions throughout the day alluded to the need to understand the multiple forms and levels of patient and public involvement in research, and distinguish between patient representatives and members of the public. Collaborative research requires flexibility, and might lead the researcher to occupy “mediating” roles such as that of the “cultural broker” or “boundary spanner”. The symposium created a forum to critically reflect on current approaches to inform improved ways of collaborating and engaging with diverse stakeholders to meaningfully impact on health and healthcare delivery. We should continue to search for ways to unpack the concept of “collaboration” to identify the purpose of collaborative relationships, the required activities and the actors involved

The impact of constructive operating lease capitalisation on key accounting ratios

Current UK lease accounting regulation does not require operating leases to be capitalised in the accounts of lessees, although this is likely to change with the publication of FRS 5. This study conducts a prospective analysis of the effects of such a change. The potential magnitude of the impact of lease capitalisation upon individual users' decisions, market valuations, company cash flows, and managers' behaviour can be indicated by the effect on key accounting ratios, which are employed in decision-making and in financial contracts. The capitalised value of operating leases is estimated using a method similar to that suggested by Imhoff, Lipe and Wright (1991), adapted for the UK accounting and tax environment, and developed to incorporate company-specific assumptions. Results for 1994 for a random sample of 300 listed UK companies show that, on average, the unrecorded long-term liability represented 39% of reported long-term debt, while the unrecorded asset represented 6% of total assets. Capitalisation had a significant impact (at the 1% level) on six of the nine selected ratios (profit margin, return on assets, asset turnover, and three measures of gearing). Moreover, the Spearman rank correlation between each ratio before and after capitalisation revealed that the ranking of companies changed markedly for gearing measures in particular. There were significant inter-industry variations, with the services sector experiencing the greatest impact. An analysis of the impact of capitalisation over the five-year period from 1990 to 1994 showed that capitalisation had the greatest impact during the trough of the recession. Results were shown to be robust with respect to key assumptions of the capitalisation method. These findings contribute to the assessment of the economic consequences of a policy change requiring operating lease capitalisation. Significant changes in the magnitude of key accounting ratios and a major shift in company performance rankings suggest that interested parties' decisions and company cash flows are likely to be affected