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Characterisation of genetic diversity in a large number of European pig populations has been undertaken with EC support. The populations sampled included local (rare) breeds, national varieties of the major international breeds, commercial lines and the Chinese Meishan breed. A second phase of the project will sample a further 50 Chinese breeds. Neutral genetic markers (AFLP and microsatellites), with individual or bulk typing, were used and compared.
DNA from 59 European pig populations was extracted on samples of about 50 individuals per population. Individuals were typed for 50 microsatellites and for 148 AFLP bands. A subset of 25 populations was typed for 20 microsatellites on pools of DNA. Allele frequencies were estimated by direct allele counting for the co-dominant markers. Frequencies of AFLP negative alleles (absent bands) were obtained by taking the square root of absent band frequencies. Within-breed variability was summarised using standard statistics: expected and observed heterozygosity, mean observed and effective numbers of alleles, and F statistics. Between-breed diversity analysis was based on a bootstrapped Neighbor-Joining (NJ) tree derived from Reynolds distances (DR). The standard distance of Nei (DS) was also calculated.
Intellectual ability may be an endophenotypic marker for bipolar disorder.
Within a large birth cohort, we aimed to assess whether childhood IQ (including both verbal IQ (VIQ) and performance IQ (PIQ) subscales) was predictive of lifetime features of bipolar disorder assessed in young adulthood.
We used data from the Avon Longitudinal Study of Parents and Children (ALSPAC), a large UK birth cohort, to test for an association between measures of childhood IQ at age 8 years and lifetime manic features assessed at age 22–23 years using the Hypomania Checklist-32 (HCL-32; n=1881 individuals). An ordinary least squares linear regression model was used, with normal childhood IQ (range 90–109) as the referent group. We adjusted analyses for confounding factors, including gender, ethnicity, handedness, maternal social class at recruitment, maternal age, maternal history of depression and maternal education.
There was a positive association between IQ at age 8 years and lifetime manic features at age 22–23 years (Pearson's correlation coefficient 0.159 (95% CI 0.120–0.198), P>0.001). Individuals in the lowest decile of manic features had a mean full-scale IQ (FSIQ) which was almost 10 points lower than those in the highest decile of manic features: mean FSIQ 100.71 (95% CI 98.74–102.6) v. 110.14 (95% CI 107.79–112.50), P>0.001. The association between IQ and manic features was present for FSIQ, VIQ and for PIQ but was strongest for VIQ.
A higher childhood IQ score, and high VIQ in particular, may represent a marker of risk for the later development of bipolar disorder. This finding has implications for understanding of how liability to bipolar disorder may have been selected through generations. It will also inform future genetic studies at the interface of intelligence, creativity and bipolar disorder and is relevant to the developmental trajectory of bipolar disorder. It may also improve approaches to earlier detection and treatment of bipolar disorder in adolescents and young adults.
Objectives: The aim of this study was to identify whether the three main primary progressive aphasia (PPA) variants would show differential profiles on measures of visuospatial cognition. We hypothesized that the logopenic variant would have the most difficulty across tasks requiring visuospatial and visual memory abilities. Methods: PPA patients (n=156), diagnosed using current criteria, and controls were tested on a battery of tests tapping different aspects of visuospatial cognition. We compared the groups on an overall visuospatial factor; construction, immediate recall, delayed recall, and executive functioning composites; and on individual tests. Cross-sectional and longitudinal comparisons were made, adjusted for disease severity, age, and education. Results: The logopenic variant had significantly lower scores on the visuospatial factor and the most impaired scores on all composites. The nonfluent variant had significant difficulty on all visuospatial composites except the delayed recall, which differentiated them from the logopenic variant. In contrast, the semantic variants performed poorly only on delayed recall of visual information. The logopenic and nonfluent variants showed decline in figure copying performance over time, whereas in the semantic variant, this skill was remarkably preserved. Conclusions: This extensive examination of performance on visuospatial tasks in the PPA variants solidifies some previous findings, for example, delayed recall of visual stimuli adds value in differential diagnosis between logopenic variant PPA and nonfluent variant PPA variants, and illuminates the possibility of common mechanisms that underlie both linguistic and non-linguistic deficits in the variants. Furthermore, this is the first study that has investigated visuospatial functioning over time in the PPA variants. (JINS, 2018, 24, 259–268)
Since 1994 the Alfred Wegener Institute (AWI) has operated an airborne radio-echo sounding system for remote-sensing studies of the polar ice caps in Antarctica and in Greenland. It is used to map ice thicknesses and internal layernigs of glaciers, ice sheets and ice shelves, and is capable of penetrating ice thicknesses of up to 4 km. The system was designed and built by AWI in cooperation with Aerodata Flugmeßtechnik GmbH, Technische Umversitat Hamburg-Harburg and the Deutsches Zentrum fur Luft- und Raumfahrt e.V. The system uses state-of-the-art techniques, and results in high vertical (5 m) as well as along-track (3.25 m) resolution. The radar signal is a 150 MHz burst with a duration of 60 or 600 ns. The peak power is 1.6 kW, and the system sensitivity is 190 dB. The short backfire principle has been adopted and optimized for antennae used on Polar2, a Dormer 228-100 aircraft, resulting in an antenna gain of 14 dB each. Digital data recording allows further processing. The quality of the recorded data can be monitored on screen and as online analogue plots during the flight.
The frequency dependence of normal pulsar radio emission is typically observed to be a power law, with some indications of a flattening or turnover at low frequencies (≲ 100 MHz). The spectrum of the Crab pulsar’s giant pulse emission has not been examined as closely. We conducted simultaneous wideband observations of the Crab pulsar, with the Parkes radio telescope and the Murchison Widefield Array, to study the spectral behaviour of its giant pulses. Our analysis shows that the mean spectral index of Crab giant pulses flattens at low frequencies, from −2.6 ± 0.5 between the Parkes bands, to −0.7 ± 1.4 between the lowest MWA subbands.
Individuals with chronic respiratory conditions may be at increased risk for pertussis. We conducted a retrospective administrative claims analysis to examine the incidence and economic burden of diagnosed pertussis among adolescents and adults in the USA with chronic obstructive pulmonary disease (COPD) or asthma. Patients aged ⩾11 years with diagnosed pertussis and pre-existing COPD (n = 343) or asthma (n = 1041) were matched 1:1 to patients with diagnosed pertussis but without COPD or asthma. Differences in all-cause costs (‘excess’ costs) during the 45-day and 3-month and 6-month periods before and after the pertussis index date were calculated; adjusted excess costs were estimated via multivariate regressions. The incidence of diagnosed pertussis was higher among patients with COPD or asthma than among matched patients. Compared with matched patients, patients with pertussis and pre-existing COPD or asthma accrued greater all-cause adjusted costs across study periods ($3694 and $1193 more, respectively, in the 45-day period; $4173 and $1301 more in the 3-month period; and $6154 and $1639 more in the 6-month period; all P < 0·0001). Patients with pre-existing COPD or asthma experience an increased economic burden after diagnosed pertussis and may especially benefit from targeted tetanus, diphtheria, and acellular pertussis vaccination strategies.
An MP tandem Van de Graaff accelerator at the University of Rochester has been employed since May 1977 to detect 14C in various terrestrial samples. The carbon sample sizes required are 1mg or less. Dating accuracies based on reproducibility now approach (± 80 years). Measurements have been made on 1850 wood, Australian sucrose, a carbon sample from Mt Shasta, a baby woolly mammoth, and an Egyptian bull mummy wrapping.
We report on the abundances of energetic particles from impulsive solar flares, including those from a survey of 228 3 He-rich events, with 3He/4He > 0.1, observed by the ISEE 3 spacecraft from 1978 August through 1991 April. The rate of occurrence of these events corresponds to ~1000 events yr−1 on the solar disk at solar maximum. Thus the resonant plasma processes that enhance 3He and heavy elements are a common occurrence in impulsive solar flares. To supply the observed fluence of 3He in large events, the acceleration must be highly efficient and the source region must be relatively deep in the atmosphere at a density of more than 1010 atoms cm−3 .3He/4He may decrease in very large impulsive events because of depletion of 3He in the source region.
The event-to-event variations in 3He/4He, H/4He, e/p, and Fe/C are uncorrelated in our event sample. Abundances of the elements show a pattern in which, relative to coronal composition, 4He, C, N, and O have normal abundance ratios, while Ne, Mg, and Si are enhanced by a factor ~2.5 and Fe by a factor ~7. This pattern suggests that elements are accelerated from a region of the corona with an electron temperature of ~3-5 MK, where elements in the first group are fully ionized (Q/A = 0.5), those in the second group have two orbital electrons (Q/A ~ 0.43), and Fe has Q/A ~ 0.28. Ions with the same gyrofrequency absorb waves of that frequency and are similarly accelerated and enhanced. Further stripping may occur after acceleration as the ions begin to interact with the streaming electrons that generated the plasma waves.
The Cosmic Background Explorer, launched November 18, 1989, has nearly completed its first full mapping of the sky with all three of its instruments: a Far Infrared Absolute Spectrophotometer (FIRAS) covering 0.1 to 10 mm, a set of Differential Microwave Radiometers (DMR) operating at 3.3, 5.7, and 9.6 mm, and a Diffuse Infrared Background Experiment (DIRBE) spanning 1 to 300 µm in ten bands. A preliminary map of the sky derived from DIRBE data is presented. Initial cosmological implications include: a limit on the Comptonization y parameter of 10−3, on the chemical potential μ parameter of 10−2, a strong limit on the existence of a hot smooth intergalactic medium, and a confirmation that the dipole anisotropy has the spectrum expected from a Doppler shift of a blackbody. There are no significant anisotropies in the microwave sky detected, other than from our own galaxy and a cosθ dipole anisotropy whose amplitude and direction agree with previous data. At shorter wavelengths, the sky spectrum and anisotropies are dominated by emission from ‘local’ sources of emission within our Galaxy and Solar System. Preliminary comparison of IRAS and DIRBE sky brightnesses toward the ecliptic poles shows the IRAS values to be significantly higher than found by DIRBE at 100 μm. We suggest the presence of gain and zero-point errors in the IRAS total brightness data. The spacecraft, instrument designs, and data reduction methods are described.
The details of the formation of the first objects, stars and galaxies and their subsequent evolution remain a cosmological unknown. Few observational probes of these processes exist. The Cosmic Infrared Background (CIB) originates from this era and measurements of its anisotropy can provide information to test models of both galaxy evolution and the growth of primordial structure. Such measurements should provide a sensitive probe of the large-scale variation in protogalaxy density at redshifts, z ~ 0.5-3, while optical galaxy surveys provide complementary information at z < 0.5 and Lyman alpha absorption forest studies and Cosmic Microwave Background measurements add information at higher redshifts.
RF-plasma MBE was used to epitaxially grow 4 – 100-nm-thick metallic
β-Nb2N thin films on hexagonal SiC substrates. When the
N/Nb flux ratios are greater than one, the most critical parameter for
high-quality β-Nb2N is the substrate temperature. The X-ray
diffraction (XRD) of films grown between 775 °C and 850 °C
demonstrates pure β-Nb2N phase formation which was also
confirmed by X-ray photoelectron spectroscopy and transmission electron
microscopy measurements. Using the (0002) and (21
1) XRD peaks of a β-Nb2N film grown at 850
°C reveals a 0.68% lattice mismatch to the 6H-SiC substrate. This
suggests that β-Nb2N can be used for high-quality
metal/semiconductor heterostructures that cannot be fabricated at present.
Metamemory describes the monitoring and knowledge about one's memory capabilities. Patients with schizophrenia have been found to be less able in differentiating between correct and false answers (smaller confidence gap) when asked to provide retrospective confidence ratings in previous studies. Furthermore, higher proportions of very-high-confident but false responses have been found in this patient group (high knowledge corruption). Whether and how these biases contribute to the early pathogenesis of psychosis is yet unclear. This study thus aimed at investigating metamemory function in the early course of psychosis.
Patients in an at-risk mental state for psychosis (ARMS, n = 34), patients with a first episode of psychosis (FEP, n = 21) and healthy controls (HCs, n = 38) were compared on a verbal recognition task combined with retrospective confidence-level ratings.
FEP patients showed the smallest confidence gap, followed by ARMS patients, followed by HCs. All groups differed significantly from each other. Regarding knowledge corruption, FEP patients differed significantly from HCs, whereas a statistical trend was revealed in comparison of ARMS and FEP groups. Correlations were revealed between metamemory, measures of positive symptoms and working memory performance.
These data underline the presence of a metamemory bias in ARMS patients which is even more pronounced in FEP patients. The bias might represent an early cognitive marker of the beginning psychotic state. Longitudinal studies are needed to unravel whether metacognitive deficits predict the transition to psychosis and to evaluate therapeutic interventions.
It is well known that web-based interventions can be effective treatments for depression. However, dropout rates in web-based interventions are typically high, especially in self-guided web-based interventions. Rigorous empirical evidence regarding factors influencing dropout in self-guided web-based interventions is lacking due to small study sample sizes. In this paper we examined predictors of dropout in an individual patient data meta-analysis to gain a better understanding of who may benefit from these interventions.
A comprehensive literature search for all randomized controlled trials (RCTs) of psychotherapy for adults with depression from 2006 to January 2013 was conducted. Next, we approached authors to collect the primary data of the selected studies. Predictors of dropout, such as socio-demographic, clinical, and intervention characteristics were examined.
Data from 2705 participants across ten RCTs of self-guided web-based interventions for depression were analysed. The multivariate analysis indicated that male gender [relative risk (RR) 1.08], lower educational level (primary education, RR 1.26) and co-morbid anxiety symptoms (RR 1.18) significantly increased the risk of dropping out, while for every additional 4 years of age, the risk of dropping out significantly decreased (RR 0.94).
Dropout can be predicted by several variables and is not randomly distributed. This knowledge may inform tailoring of online self-help interventions to prevent dropout in identified groups at risk.
Over the past decade, a growing number of deep imaging surveys have started to provide meaningful constraints on the population of extrasolar giant planets at large orbital separation. Primary targets for these surveys have been carefully selected based on their age, distance and spectral type, and often on their membership to young nearby associations where all stars share common kinematics, photometric and spectroscopic properties. The next step is a wider statistical analysis of the frequency and properties of low mass companions as a function of stellar mass and orbital separation. In late 2009, we initiated a coordinated European Large Program using angular differential imaging in the H band (1.66 μm) with NaCo at the VLT. Our aim is to provide a comprehensive and statistically significant study of the occurrence of extrasolar giant planets and brown dwarfs at large (5-500 AU) orbital separation around ~150 young, nearby stars, a large fraction of which have never been observed at very deep contrast. The survey has now been completed and we present the data analysis and detection limits for the observed sample, for which we reach the planetary-mass domain at separations of ≳50 AU on average. We also present the results of the statistical analysis that has been performed over the 75 targets newly observed at high-contrast. We discuss the details of the statistical analysis and the physical constraints that our survey provides for the frequency and formation scenario of planetary mass companions at large separation.
Results are reported on several new glass and glass-ceramic waste
formulations for plutonium disposition. The approach proposed involves
employing existing calcined high level waste (HLW) present at the Idaho
Chemical Processing Plant (ICPP) as an additive to: 1) aid in the formation
of a durable waste form and 2) decrease the attractiveness level of the
plutonium from a proliferation viewpoint. The plutonium, PuO2,
loadings employed were 15 wt% (glass) and 17 wt% (glass-ceramic). Results in
the form of x-ray diffraction patterns, microstructure and durability tests
are presented on cerium surrogate and plutonium loaded waste forms using
simulated calcined HLW and demonstrate that durable phases, zirconia and
zirconolite, contain essentially all the plutonium.