The Spectrum of Pluto, 0.40 - 0.93 μ\mum I. Secular and longitudinal distribution of ices and complex organics

Context. During the last 30 years the surface of Pluto has been characterized, and its variability has been monitored, through continuous near-infrared spectroscopic observations. But in the visible range only few data are available. Aims. The aim of this work is to define the Pluto's relative reflectance in the visible range to characterize the different components of its surface, and to provide ground based observations in support of the New Horizons mission. Methods. We observed Pluto on six nights between May and July 2014, with the imager/spectrograph ACAM at the William Herschel Telescope (La Palma, Spain). The six spectra obtained cover a whole rotation of Pluto (Prot = 6.4 days). For all the spectra we computed the spectral slope and the depth of the absorption bands of methane ice between 0.62 and 0.90 $\mu$m. To search for shifts of the center of the methane bands, associated with dilution of CH4 in N2, we compared the bands with reflectances of pure methane ice. Results. All the new spectra show the methane ice absorption bands between 0.62 and 0.90 $\mu$m. The computation of the depth of the band at 0.62 $\mu$m in the new spectra of Pluto, and in the spectra of Makemake and Eris from the literature, allowed us to estimate the Lambert coefficient at this wavelength, at a temperature of 30 K and 40 K, never measured before. All the detected bands are blue shifted, with minimum shifts in correspondence with the regions where the abundance of methane is higher. This could be indicative of a dilution of CH4:N2 more saturated in CH4. The longitudinal and secular variations of the parameters measured in the spectra are in accordance with results previously reported in the literature and with the distribution of the dark and bright material that show the Pluto's albedo maps from New Horizons.Comment: This manuscript may change and improve during the reviewing process. The data reduction and calibration is reliable and has been checked independently using different reduction approaches. The data will be made publicily available when the paper is accepted. If you need them before, please, contact the autho

Prevalence and cumulative incidence of food hyper-sensitivity in the first 10 years of life

Background - Prevalence, incidence and natural history of food hypersensitivity (FHS) and its trends in an unselected cohort of older children are unclear.Methods - A birth cohort born on the Isle of Wight (UK) between 2001 and 2002 was followed up prospectively. Children were clinically examined and skin prick tested at set times and invited for food challenges when indicated. At 10 years of age, children were also invited for a blood test.Results - A total of 969 children were recruited at 12 weeks of pregnancy, and 92.9%, 88.5%, 91.6% and 85.3% were assessed at 1, 2, 3 and 10 years. Prevalence of sensitization to any allergen over 10 years was 186 of 969 (19.2%; 95% CI: 16.84–21.8) and 108 of 969 (11.2%; 95% CI: 9.31–13.29) children were sensitized to at least one predefined food allergen. Excluding wheat (due to cross-reactivity with pollen), 40 of 969 (4.1%; 95% CI: 3.19–5.32) children were sensitized to a predefined food allergen. Using food challenges and/or a good clinical history, the cumulative incidence of food hypersensitivity (FHS) in the first decade of life was 64 of 947 (6.8%, 95% CI: 5.2–8.4), while the prevalence of FHS at 10 years was 30 of 827 (3.6%, 95% CI: 2.54–5.15). The vast majority, 25 of 827 (3.0%, 95% CI: 1.8–4.2), suffered from IgE-mediated food allergy, while 5 of 827 (0.6%, 95% CI: 0.07–1.3) had non-IgE-mediated food allergy/food intolerance.Conclusions - By the age of 10 years, 6.8% of children suffered from FHS based on food challenges and a good clinical history. There was a large discrepancy between reported and diagnosed FHS

Changing prevalence of wheeze, rhinitis and allergic sensitisation in late childhood: findings from 2 Isle of Wight birth cohorts’ 12-years apart

Background: While the prevalence of asthma in children is decreasing or remaining the same, time-trends in the prevalence of rhinitis in children are not known. Understanding sensitisation trends may help inform about trends in asthma and rhinitis prevalence.Objective: To assess time -trends of wheeze, rhinitis and aero-allergen sensitisation prevalence at 10 years of age we compared two birth cohorts established 12 years apart. To gain insight into differences in disease prevalence we assessed association of family-history, early life exposures and sensitisation with wheeze and rhinitis in each cohort.Methods: The IoW (Isle-of-Wight) and FAIR (Food-Allergy-and-Intolerance-Research) unselected birth cohorts were established in 1989 and 2001 in IoW. Identical ISAAC questionnaire and Skin Prick test data were collected and compared at 10 years of age.Results: Over the 12 year period from 2001 to 2012, prevalence of lifetime-wheeze, current-wheeze, and those ever-treated-for-asthma decreased by 15.9% (45.5-vs-29.6,p<0.001), 3.9% (18.9-vs-15, p=0.020) and 8.2% (31.7-vs-23.5, p=0.001) respectively. Conversely, current-rhinitis and lifetime-rhinitis prevalence increased by 5.5% (22.6-vs-28.1, p=0.004) and 13% (18.6-vs-31.7, p<0.001) respectively. Atopic status remained stable, however house dust mite (HDM) sensitisation decreased by 5.6% (19.2-vs-13.6, p=0.004) and grass sensitisation increased by 3.5% (12.9-vs-16.4, p=0.054). Male-sex, parental history of asthma and HDM sensitisation were significantly associated with lifetime-wheeze in both cohorts while maternal smoking during pregnancy was a significant risk factor only in the earlier IoW-cohort. Parental history of rhinitis and grass sensitisation were significantly associated with lifetime-rhinitis in both cohorts while HDM sensitisation was significant only for the IoW-cohort.Conclusion: Contrasting changes were noted with falling wheeze and HDM sensitisation but rising rhinitis and grass sensitisation prevalence. Changing prevalence of aero-allergen sensitisations may explain the different time trends observed in these cohorts

Health-related quality of life in children with perceived and diagnosed food hypersensitivity

The few studies measuring health-related quality of life (HRQL) in food hypersensitivity (FHS) have found significantly reduced HRQL in patients and their families, particularly in the areas of family and social activities, emotional issues and family economy. One aspect that has not been studied is the effect of suspected FHS (food allergy/intolerance) vs. diagnosed FHS [based on a food challenge or a positive skin prick test (SPT) and good clinical history] on HRQL. Therefore, the aim of this study was to investigate the HRQL in children with a proven diagnosis of FHS vs. those with reported FHS.MethodsWe have utilized the 10-yr old follow-up cohort of the Food Allergy and Intolerance Research (FAIR) study from the Isle of Wight and assessed the child's HRQL with the Food Allergy Quality of Life Questionnaire – Parent form (FAQLQ-PF) which measures HRQL using four domains: food anxiety, emotional impact, social and dietary limitation.ResultsWhen comparing the two groups of children (proven FHS vs. perceived FHS), no difference in HRQL was found, although food anxiety showed a p-value of (p = 0.062). This was also the case when correcting for all confounding factors identified.ConclusionWe have found that having a clear diagnosis of FHS is not an independent predictor of HRQL. Future studies are required comparing two more similar groups. We also need to focus more on the effect of continuous input from the multidisciplinary team on HRQL and which particular factors of FHS management affect HRQL

Association between healthy eating in pregnancy and allergic status of the offspring in childhood

During the past few decades there has been a steady increase in the prevalence of noncommunicable diseases, including allergic disease. Changing lifestyle and subsequent diet may explain this increase seen in the prevalence of atopic disease. Epidemiologic evidence also suggests that diet may be key in the prevention of allergic disease. [1] There are 3 important characteristics in terms of the maternal diet that have been investigated for the prevention of allergic disease: (1) the role of particular nutrients, such as vitamins (A, D, and E), zinc, and fatty acids; (2) the role of particular foods, such as fruits and vegetables and fish; and (3) the total dietary intake, such as a Mediterranean diet or a healthy diet. Research using the healthy eating index tool, specific to the pregnancy diet, found no association between overall healthy eating score and recurrent wheeze in infants at the age of 3 years. [2] However, maternal intake of celery and citrus fruit specifically has been associated with an increased risk of sensitization to food allergens in 2-year-olds. [3] One case-control study found no effect of consumption of fish, butter, and margarine on the development of atopic sensitization in the offspring of allergic mothers; however, a protective effect of fish intake (2–3 times a week or more) was identified in the nonallergic mothers' group with the risk of food sensitization in the offspring reduced by greater than a third. [4] Thus, the question is whether the associations seen are due to the individual nutrients or foods or whether it is part of an overall nutritional composition of the weaning diet. In this study, we aimed to investigate whether maternal diet, specifically seafood intake during pregnancy, is associated with the infant's allergic outcomes in a well-characterized birth cohort with allergy at 3 and 10 years of age

Very low prevalence of IgE mediated wheat allergy and high levels of cross-sensitisation between grass and wheat in a UK birth cohort

BackgroundPatients often report adverse reactions to wheat. Interpretation of sensitization to wheat pollen and flour with/without sensitization to grass pollen is a clinical problem.AimWe set out to determine the prevalence of wheat allergy in a birth cohort (10/11 year olds) and investigate the usefulness of performing skin prick tests (SPT), specific IgE tests and component resolved diagnostics to wheat pollen and flour.MethodsThe Food Allergy and Intolerance Research (FAIR) birth cohort included babies born on the Isle of Wight (UK) between September 2001–August 2002 (n = 969). Children were followed up at 1, 2, 3 and 10/11 years. 588 children had SPTs to wheat pollen and grass during the 10 year follow-up. 294 children underwent further SPT to wheat flour and 246 had specific IgE testing to wheat and grass.ResultsEight children underwent oral food challenges (OFC). We diagnosed 0.48 % (4/827; 95 % CI 0–1 %) children with wheat allergy based on OFC. 16.3 % (96/588) were sensitized to grass pollen, 13.4 % (79/588) to wheat pollen; 78 % (75/96) sensitized to both. Only one child was sensitized to wheat flour and wheat pollen, but not grass pollen. For specific IgE, 15.0 % (37/246) and 36.2 % (89/246) were sensitized to wheat and grass pollen, with 40.5 % (36/89) sensitized to both. Of the 37 children sensitized to wheat, 3 (8.1 %) were sensitized to omega 5 gliadin, 1 (2.7 %) to wheat lipid transfer protein and 1 to wheat gliadin.ConclusionClinicians should be aware of the high level of cross-sensitization when performing tests to wheat and grass pollen i.e. sensitisation to wheat specific IgE and wheat pollen SPT should be assessed in the presence of grass pollen SPT and/or specific IgE

Spontaneous Polarisation Build up in a Room Temperature Polariton Laser

We observe the build up of strong (~50%) spontaneous vector polarisation in emission from a GaN-based polariton laser excited by short optical pulses at room temperature. The Stokes vector of emitted light changes its orientation randomly from one excitation pulse to another, so that the time-integrated polarisation remains zero. This behaviour is completely different to any previous laser. We interpret this observation in terms of the spontaneous symmetry breaking in a Bose-Einstein condensate of exciton-polaritons

Spectroscopy of Pluto, 380-930 Nm at Six Longitudes

We have obtained spectra of the Pluto-Charon pair (unresolved) in the wavelength range 380-930 nm with resolution approx..450 at six roughly equally spaced longitudes. The data were taken in May and June, 2014, with the 4.2-m Isaac Newton Telescope at Roque de Los Muchachos Observatory in the Canary Islands, using the ACAM (auxiliary-port camera) in spectrometer mode, and using two solar analog stars. The new spectra clearly show absorption bands of solid CH4 at 620, 728, and 850-910 nm, which were known from earlier work. The 620-nm CH4 band is intrinsically very weak, and its appearance indicates a long optical path-length through the ice. This is especially true if it arises from CH4 dissolved in N2 ice. Earlier work (Owen et al. Science 261, 745, 1993) on the near-infrared spectrum of Pluto (1-2.5 microns) has shown that the CH4 bands are shifted to shorter wavelengths because the CH4 occurs as a solute in beta-phase crystalline N2. The optical path-length through the N2 crystals must be on the order of several cm to produce the N2 band observed at 2.15 microns. The new spectra exhibit a pronounced red slope across the entire wavelength range; the slope is variable with longitude, and differs in a small but significant way from that measured at comparable longitudes by Grundy & Fink (Icarus 124, 329, 1996) in their 15-year study of Pluto's spectrum (500-1000 nm). The new spectra will provide an independent means for calibrating the color filter bands on the Multispectral Visible Imaging Camera (MVIC) (Reuter et al. Space Sci. Rev. 140, 129, 2008) on the New Horizons spacecraft, which will encounter the Pluto-Charon system in mid-2015. They will also form the basis of modeling the spectrum of Pluto at different longitudes to help establish the nature of the non-ice component(s) of Pluto's surface. It is presumed that the non-ice component is the source of the yellow-red coloration of Pluto, which is known to be variable across the surface

The Albedo, Size, and Density of Binary Kuiper Belt Object (47171) 1999 TC36

We measured the system-integrated thermal emission of the binary Kuiper Belt Object 1999 TC36 at wavelengths near 24 and 70 microns using the Spitzer space telescope. We fit these data and the visual magnitude using both the Standard Thermal Model and thermophysical models. We find that the effective diameter of the binary is 405 km, with a range of 350 -- 470 km, and the effective visible geometric albedo for the system is 0.079 with a range of 0.055 -- 0.11. The binary orbit, magnitude contrast between the components, and system mass have been determined from HST data (Margot et al., 2004; 2005a; 2005b). Our effective diameter, combined with that system mass, indicate an average density for the objects of 0.5 g/cm3, with a range 0.3 -- 0.8 g/cm3. This density is low compared to that of materials expected to be abundant in solid bodies in the trans-Neptunian region, requiring 50 -- 75% of the interior of 1999 TC36 be taken up by void space. This conclusion is not greatly affected if 1999 TC36 is ``differentiated'' (in the sense of having either a rocky or just a non-porous core). If the primary is itself a binary, the average density of that (hypothetical) triple system would be in the range 0.4 -- 1.1 g/cm3, with a porosity in the range 15 -- 70%.Comment: ApJ, in press (May, 2006