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Breast-feeding is thought to facilitate young children’s acceptance of new foods, including vegetables, but the evidence for this relationship appears inconsistent across studies. Increasing children’s vegetable intake remains challenging; therefore the present study aimed to investigate whether breast-feeding duration predicts vegetable intake in 2–6-year-old children.
Actual vegetable intake was measured in studies across three European countries. General linear model analyses with breast-feeding duration, sex and age of the child and maternal education as variables were used to predict children’s vegetable intake per country. Additionally, the relationships between child eating behaviour characteristics (asked through the Child Eating Behaviour Questionnaire) and vegetable intake were investigated via Pearson correlations.
Daycare centres, schools and home settings in Denmark, Greece and the Netherlands.
Children aged 2–6 years (n 750).
Breast-feeding duration was positively associated with children’s vegetable intake at 2–6 years old in Denmark (P<0·01) and the Netherlands (P<0·05), but not in Greece (P=0·17). Age of the child, maternal education and sex of the child did not predict vegetable intake in our sample. All countries showed an inverse relationship between food neophobia and children’s vegetable intake and a positive relationship between vegetable liking and intake.
The present study found that breast-feeding duration is a predictor of later vegetable intake, but that current child eating behaviour characteristics, such as vegetable liking, food neophobia and enjoyment of food, also influence vegetable intake. Besides encouragement of breast-feeding duration, strategies that support vegetable liking and food enjoyment and decrease food neophobia are needed to support young children’s vegetable intake.
We study the geometric and topological properties of strange non-chaotic attractors created in non-smooth saddle-node bifurcations of quasiperiodically forced interval maps. By interpreting the attractors as limit objects of the iterates of a continuous curve and controlling the geometry of the latter, we determine their Hausdorff and box-counting dimension and show that these take distinct values. Moreover, the same approach allows us to describe the topological structure of the attractors and to prove their minimality.
Measles, mumps, rubella (MMR) and varicella zoster virus (VZV) infection can cause serious diseases and complications in the HIV-positive population. Due to successful vaccination programmes measles, mumps and congenital rubella syndrome has become neglected in Germany. However, recent outbreaks of measles have occurred from import-associated cases. In this cross-sectional study the serostatus for MMR and VZV in 2013 HIV-positive adults from three different university outpatient clinics in Bonn (n = 544), Cologne (n = 995) and Munich (n = 474) was analysed. Sera were tested for MMR- and VZV-specific immunglobulin G antibodies using commercial immunoassays. Seronegativity was found in 3% for measles, 26% for mumps, 11% for rubella and 2% for VZV. Regarding MMR, 35% of patients lacked seropositivity against at least one infectious agent. In multivariable analysis younger age was strongly associated with seronegativity against all four viruses, measles, mumps, rubella (P < 0·001, P < 0·001 and P = 0·001, respectively) and VZV (P = 0·001). In conclusion, there is high need for MMR and VZV vaccination in people living with HIV in Germany born in 1970 or later. Thus, systematic MMR and VZV antibody screening and vaccination should be implemented in the HIV-positive population to prevent serious disease and complications of vaccine-preventable diseases.
Approximately half of the variation in wellbeing measures overlaps with variation in personality traits. Studies of non-human primate pedigrees and human twins suggest that this is due to common genetic influences. We tested whether personality polygenic scores for the NEO Five-Factor Inventory (NEO-FFI) domains and for item response theory (IRT) derived extraversion and neuroticism scores predict variance in wellbeing measures. Polygenic scores were based on published genome-wide association (GWA) results in over 17,000 individuals for the NEO-FFI and in over 63,000 for the IRT extraversion and neuroticism traits. The NEO-FFI polygenic scores were used to predict life satisfaction in 7 cohorts, positive affect in 12 cohorts, and general wellbeing in 1 cohort (maximal N = 46,508). Meta-analysis of these results showed no significant association between NEO-FFI personality polygenic scores and the wellbeing measures. IRT extraversion and neuroticism polygenic scores were used to predict life satisfaction and positive affect in almost 37,000 individuals from UK Biobank. Significant positive associations (effect sizes <0.05%) were observed between the extraversion polygenic score and wellbeing measures, and a negative association was observed between the polygenic neuroticism score and life satisfaction. Furthermore, using GWA data, genetic correlations of -0.49 and -0.55 were estimated between neuroticism with life satisfaction and positive affect, respectively. The moderate genetic correlation between neuroticism and wellbeing is in line with twin research showing that genetic influences on wellbeing are also shared with other independent personality domains.
In view of the limitation on length set by the cost of producing the IAU Reports, the present report can only be a selection of the most important advances during the past three years and not a complete review of the field.
Attempting to pick out a few points of interest, since the last report improvements have been made in recording solar X-ray spectra and in high spatial resolution imaging; the OSO satellite programme continues to produce valuable data. The eclipse experiments planned for March 1970 will, if successful, provide a considerable amount of new information. The solar iron abundance is still a subject of interest in view of the revision of oscillator strengths used in the photospheric analyses. Further interplanetary observations have shown that the general nature of the solar wind at the Earth does not depend on the phase of the solar activity cycle, and have revealed large increases in the abundance of helium in the solar wind following solar flares.
The Sco OB2 Association is convenient for investigation as it has a high galactic latitude and is therefore remote from the confusion of the galactic plane. Its distance is accurately known and this permits fairly precise estimates to be made of the Lyman continuum photon fluxes responsible for the radio emission. It includes the ρ Ophiuci dark cloud where star formation is occurring.
The aim of this study was to evaluate the quality of life in patients with vascular chronic Q fever at time of diagnosis and during follow-up. Based upon the SF-36 questionnaire, the mean physical and mental health of each patient were assessed at 3-month intervals for up to 18 months. A total of 26 patients were included in the study. At time of diagnosis, the mean physical health and mental health score was 50·6 [95% confidence interval (CI) 46·7–54·4] and 44·6 (95% CI 41·6–47·5), respectively. During treatment, the mean physical health score declined significantly by 1·7 points each 3 months (P < 0·001) to 40·8 (95% CI 34·4–45·1). The mean mental health score significantly and steadily increased towards 51·2 (95% CI 46·9–54·3) during follow-up (P = 0·026). A total of 23% of patients were cured after 18 months of follow-up. In conclusion, quality of life at time of diagnosis for patients with vascular chronic Q fever is lower compared to a similar group of patients, matched for age and gender, with an aortic abdominal aneurysmal disease, and physical health decreases further after starting treatment. Considering the low percentage of cure, the current treatment of vascular chronic Q fever patients may require a separate strategy from that of endocarditis in order to increase survival.
The electronic spectroscopy of various polycyclic aromatic hydrocarbon (PAH) molecules has been studied in the laboratory at low temperatures using both molecular beam and matrix isolation spectroscopy techniques. While molecular beam spectra can be readily compared to astronomical observations, the band positions measured in Ne and Ar matrices are extrapolated to obtain rather good estimates for the same transitions in the gas phase. Absolute absorption cross sections are determined for gas-phase and matrix spectra by comparing them with calibrated solution spectra. All laboratory results are analyzed and discussed in view of the role that PAHs can play as carriers of the diffuse interstellar bands (DIBs). Our studies suggest that regular neutral PAHs are not responsible for any of the known strong DIBs.
Polycyclic aromatic hydrocarbon (PAH) molecules have been long considered promising candidates for the carriers of the diffuse interstellar bands (DIBs). The PAH-DIB hypothesis, however, raises two major issues. First, the number of interstellar PAH species is potentially orders of magnitude larger than the number of DIBs. Second, the absorption spectrum of a PAH is in general dominated by bands found at UV wavelengths while, conversely, DIBs are absent from the UV wavelength domain and arise at visible and near IR wavelengths. These issues do not necessarily weaken the PAH-DIB hypothesis and can actually allow us to refine it. In that context, we analyze the UV/vis absorption spectra of PAH molecules isolated in Ne matrices and propose that polyynyl-substituted PAHs, or similar species, are valid candidates for the carriers of the DIBs. Finally, a possible lifecycle for DIB-carrying PAHs is presented.
This study examines historical variation in individual trajectories of heavy drinking and marijuana use from age 18 to 22. Unlike most studies that have examined cohort differences in drug use, it focuses on differences in both level of use and rates of change (growth). Nearly 39,000 youths from the high school classes of 1976–2004 were surveyed at biennial intervals between the ages of 18 and 22 as part of the national Monitoring the Future study. Between 1976 and 2004, adolescent heavy drinking decreased substantially. However, because the age 18–22 heavy drinking growth rate increased threefold for males and sixfold for females during this period, heavy drinking among 21- to 22-year-olds remained largely stable. The growth rate for marijuana use was more stable across cohorts, and historical declines in use were sizable across the entire 18–22 age band. Generally, historical variation in use was unrelated to college status and living arrangements as well as to historical changes in the distribution of young adult social roles. Findings suggest that historical fluctuations in use were less the result of proximal young adult factors and more the result of historical variation in distal adolescent factors, the effect of which diminished with age, especially for heavy drinking.
We have investigated microstructural properties of GaAs:N and GaN:As layers using transmission electron microscopy. The samples were grown onto (001)-oriented GaAs substrates by RF-plasma assisted molecular beam epitaxy. It has been found that during the GaAs/GaAs:N epitaxial growth the supplied active nitrogen atoms gave rise to nanometer-size GaN crystallites formed in the GaAs matrix. In addition, silicon incorporation showed abnormal behavior at the two interfaces of the thin GaAs:N layer embedded in GaAs. A model is proposed for the formation of GaN crystallites in GaAs during the growth. In the GaN:As growth, the layer exhibited columnar growth, resulting in domains with different crystallographic orientation. With an increase of the film thickness, the zincblende structure changed to the wurtzite phase of GaN. The distribution of arsenic through the layer thickness was found to be inhomogeneous and be much higher near the GaN/GaAs interface compared to the region near the surface.
The design of a novel spectrometer based on a thin film diode in combination with an electro statically tunable micro machined mirror will be presented. The semi transparent diode is introduced into a standing wave created in front of a reflector to sample the profile of the standing wave. Varying the position of the reflector results in a shift of the phase of the standing waves and thus in a change of the optical generation profile within the detector. The spectral information of the incoming light can be determined by the Fourier transformation of the transient response of the sensor. An analytical optical model will be presented which facilitates the evaluation of different detector concepts. The model will be applied to discuss different device designs regarding the resolution of the spectrometer, the spectral range and the linearity.
Formation of defects during Zn diffusion into undoped and Fe-doped InP single crystals at 700°C has been observed by transmission electron microscopy for various diffusion conditions. The observations are correlated with Zn concentration profiles obtained by electron microprobe measurements and secondary-ion mass spectrometry. The results allow the conclusion that indiffusing interstitial Zn can occupy In sublattice sites via a kick-out reaction. Under appropriate diffusion conditions supersaturations of In self-interstitial atoms result leading to defect formation. Observations in Fe-doped InP suggest that Zn also replaces Fe on In sublattice sites leading to redistribution and to precipitation of Fe.
Silicon single crystal wafers are lithographically patterned and etched for via holes by means of RIBE, RIE and ECR based techniques. The damage introduced by etching is analyzed using charge collection microscopy. This technique probes sensitively the occurrence of electrically active defects due to their altered electron hole recombination properties compared to the bulk material. Furthermore, investigations of the temperature dependence of the EBIC contrast give informations about the physical mechanisms for the recombination. The experiments revealed a substantial increase [several %] of the EBIC contrast in the etched part of the pattern, i.e. electrically active damage is introduced by the etching technique, giving rise to enhanced recombination. Measurements of the diffusion length in etched and unetched areas of the specimen reveal identical values, i.e. the damage is confined close to the surface. Using the different etching methods quantitatively different defect levels are found. Measurements of the temperature dependence of the EBIC contrast aimed to reveal the physical nature of the defects show a drastic increase of the contrast with decreasing temperature. This increase can be described by two regimes in an Arrhenius plot with a linear characteristic of different slopes.
Recent reports on high transient transverse voltages at room temperature in YBa2Cu3O7 and PrxYl-xBa2Cu3O7 thin films grown on SrTiO3 single crystal substrates, with a tilt angle between the [ 001 ] cubic axis and the substrate surface plane, have been interpreted by thermoelectric fields transverse to a laser-induced temperature gradient which are caused by the non-zero off diagonal elements of the Seebeck tensor. We have studied this effect in epitaxially grown Pr- doped, as well as undoped YBa2Cu3O7, thin films and observed for a 2 mm long YBa2Cu3O7 strip exposed to a UV photon fluence of 100 mJ/cm2 signals as large as 30 V. The unexpected high values for the signals and their doping dependence are discussed within the frame of a model based on a thermopile arrangement, the growth induced defect structure and the doping induced modifications of the material properties.
The phenomenon of second harmonic generation has been studied from the earliest days of nonlinear optics.[l] To date the most impressive results in terms of conversion efficiency for as low an input power as possible have been obtained in channel waveguides made from inorganic materials. However, when their second order nonlinearities (10s of pm/V) are compared with those of organic materials (10s → 100s pmn/V), it is clear that organic materials should eventually produce much better harmonic conversion efficiencies. 
Modal Dispersion Phase Matching appears to be currently much better adapted to parametric mixing in polymeric material waveguides than Quasi Phase Matching. For second harmonic generation at telecommunication wavelengths, using organic materials should allow better performance than with ferroelectric crystals. Promising results are expected in view of theoretical expectations and continuously improving experimental past and current results.
Of eight acute infections in German tourists caused by sandfly fever virus, serotype Toscana (TOS). and diagnosed clinically and serologically, seven were acquired during visits to Tuscany, Italy, and one to Coimbra, Portugal. An indirect immunofluorescence assay (IFA) using infected cells, and a newly developed enzyme-immunoassay (EIA) using crude virus antigen prepared from infected Vero-E6 cells was used to detect anti-TOS IgM and IgG. In a seroepidemiological survey of 859 health care workers and medical students, anti-TOS IgG was detected in 1·0% by IFA, and in 0·7% by EIA. In 2034 German patients hospitalized for various diseases, 1·6% were positive for anti-TOS IgG by IFA, and 0·8% by EIA. Anti-TOS IgG was detected in 43 samples of commercial immunoglobulins at titres of 10–1000 by EIA. Although the seroprevalence of antibodies to TOS is low in Germany, TOS infection should be considered in patients returning from endemic areas who complain of fever, and headaches, and have symptoms of meningitis.
Effective infection control measures during norovirus outbreaks are urgently needed in places where vulnerable individuals gather. In the present study, the effect of a number of measures was investigated in daily practice. Forty-nine Dutch nursing homes were monitored prospectively for norovirus outbreaks during two winter seasons. A total of 37 norovirus outbreaks were registered. Control measures were most effective when implemented within 3 days after onset of disease of the first patient. Measures targeted at reduced transmission between persons, via aerosols, and via contaminated surfaces reduced illness in staff and in residents. Reducing illness in staff results in fewer costs for sick leave and substitution of staff and less disruption in the care of residents. The effect of control measures on outbreak duration was limited. This is the first intervention study examining the effect of control measures. Further research is needed to extend and refine the conclusions.