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We report the discovery of one unique cataclysmic variable drawn from the Hamburg Quasar Survey, HS 2331 + 3905. Follow-up observations obtained over three years unveiled a very unusual picture. The large amplitude 3.5 h radial velocity variations obtained from our optical spectroscopy is not the orbital period of the system, as one would normally expect. Instead, extensive CCD photometry strongly suggests that HS 2331 + 3005 is a short orbital period cataclysmic variable with Рorb = 81.09 min, containing a cold white dwarf which appears to exhibit ZZ Ceti pulsations.
From a 45ks Chandra observation of V42G Oph we have obtained high-resolution X-ray spectra at moderate signal-to-noise, and a, good quality, uninterrupted lightcurve. The spectra are reasonably fit with a cooling flow model, similar to EX Hya and U Gem. Our analysis of the Chandra and additional X-ray/optical lightcurves reveals a persistent modulation at 4.2 hr from 1988 to 2003, likely the white dwarf spin period indicating an intermediate polar nature for V426 Oph.
As a pilot study to investigate whether personalized medicine approaches could have value for the reduction of malaria-related mortality in young children, we evaluated questionnaire and biomarker data collected from the Mother Offspring Malaria Study Project birth cohort (Muheza, Tanzania, 2002–2006) at the time of delivery as potential prognostic markers for pediatric severe malarial anemia. Severe malarial anemia, defined here as a Plasmodium falciparum infection accompanied by hemoglobin levels below 50 g/L, is a key manifestation of life-threatening malaria in high transmission regions. For this study sample, a prediction model incorporating cord blood levels of interleukin-1β provided the strongest discrimination of severe malarial anemia risk with a C-index of 0.77 (95% CI 0.70–0.84), whereas a pragmatic model based on sex, gravidity, transmission season at delivery, and bed net possession yielded a more modest C-index of 0.63 (95% CI 0.54–0.71). Although additional studies, ideally incorporating larger sample sizes and higher event per predictor ratios, are needed to externally validate these prediction models, the findings provide proof of concept that risk score-based screening programs could be developed to avert severe malaria cases in early childhood.
The gestational milieu is an important influence on fetal development and long-term disease risk. Here we assess relationships between maternal pregnancy inflammation, indicated by C-reactive protein (CRP), and offspring anthropometric outcomes measured soon after birth. Data come from female participants (n=327, age 24.4–30.2 years) in a longitudinal study located in Metropolitan Cebu, Philippines. Between 2009 and 2014, pregnancy interviews (n=429) were conducted during which questionnaire and anthropometric data were obtained along with dried blood spot cards for CRP measurement. Offspring body weight, length, head circumference and five skinfold thickness measures were obtained soon after birth. Maternal pregnancy CRP was borderline (−1.11±0.64 days/log-mg/l; P<0.1) inversely related to gestational age at delivery, but did not increase the likelihood of preterm delivery. After adjusting for maternal pre-pregnancy body mass index, height, pregnancy adiposity, age, parity and other covariates, CRP was significantly, inversely related to offspring body weight (−0.047±0.017 kg/log-mg/l), length (−0.259±0.092 cm/log-mg/l) and sum of skinfolds (−0.520±0.190 mm/log-mg/l) (all P<0.05), and borderline inversely related to offspring head circumference (−0.102±0.068 cm/log-mg/l; P<0.1). Notably, relationships were continuous across the full CRP range, and not limited to unusually high levels of inflammation. These findings point to an important role of maternal non-specific immune activation as a predictor of offspring birth outcomes. In light of evidence that early life microbial, nutritional and stress experiences influence adult inflammatory regulation, these findings point to inflammation as a potential pathway for the intergenerational transmission of maternal experience to offspring health.
Network analyses on psychopathological data focus on the network structure and its derivatives such as node centrality. One conclusion one can draw from centrality measures is that the node with the highest centrality is likely to be the node that is determined most by its neighboring nodes. However, centrality is a relative measure: knowing that a node is highly central gives no information about the extent to which it is determined by its neighbors. Here we provide an absolute measure of determination (or controllability) of a node – its predictability. We introduce predictability, estimate the predictability of all nodes in 18 prior empirical network papers on psychopathology, and statistically relate it to centrality.
We carried out a literature review and collected 25 datasets from 18 published papers in the field (several mood and anxiety disorders, substance abuse, psychosis, autism, and transdiagnostic data). We fit state-of-the-art network models to all datasets, and computed the predictability of all nodes.
Predictability was unrelated to sample size, moderately high in most symptom networks, and differed considerable both within and between datasets. Predictability was higher in community than clinical samples, highest for mood and anxiety disorders, and lowest for psychosis.
Predictability is an important additional characterization of symptom networks because it gives an absolute measure of the controllability of each node. It allows conclusions about how self-determined a symptom network is, and may help to inform intervention strategies. Limitations of predictability along with future directions are discussed.
Faster eating rates are associated with increased energy intake, but little is known about the relationship between children’s eating rate, food intake and adiposity. We examined whether children who eat faster consume more energy and whether this is associated with higher weight status and adiposity. We hypothesised that eating rate mediates the relationship between child weight and ad libitum energy intake. Children (n 386) from the Growing Up in Singapore Towards Healthy Outcomes cohort participated in a video-recorded ad libitum lunch at 4·5 years to measure acute energy intake. Videos were coded for three eating-behaviours (bites, chews and swallows) to derive a measure of eating rate (g/min). BMI and anthropometric indices of adiposity were measured. A subset of children underwent MRI scanning (n 153) to measure abdominal subcutaneous and visceral adiposity. Children above/below the median eating rate were categorised as slower and faster eaters, and compared across body composition measures. There was a strong positive relationship between eating rate and energy intake (r 0·61, P<0·001) and a positive linear relationship between eating rate and children’s BMI status. Faster eaters consumed 75 % more energy content than slower eating children (Δ548 kJ (Δ131 kcal); 95 % CI 107·6, 154·4, P<0·001), and had higher whole-body (P<0·05) and subcutaneous abdominal adiposity (Δ118·3 cc; 95 % CI 24·0, 212·7, P=0·014). Mediation analysis showed that eating rate mediates the link between child weight and energy intake during a meal (b 13·59; 95 % CI 7·48, 21·83). Children who ate faster had higher energy intake, and this was associated with increased BMI z-score and adiposity.
To investigate whether specific symptoms of attention deficit hyperactivity disorder (ADHD) can help identify ADHD patients with mind wandering.
Subjects were adults ages 18–55 of both sexes (n=41) who completed the Mind-Wandering Questionnaire (MWQ) and the ADHD module of the Schedule for Affective Disorders and Schizophrenia for School-Age Children Epidemiologic Version. We used Spearman’s rank correlation and Pearson’s χ2 analyses to examine associations between the ADHD module and the MWQ and receiver operator characteristic (ROC) analyses to evaluate the diagnostic efficiency of the ADHD module.
Out of the three ADHD domains, the inattentive ADHD scores had the strongest association with the MWQ (total: rs=0.34, df=39, p=0.03; inattentive: rs=0.38, df=39, p=0.02; Hyperactive: rs=0.17, df=39, p=0.28). Correlation analyses between individual items on the ADHD module and the MWQ showed that two inattention items (‘failure to pay attention to detail’ and ‘trouble following instructions’) were positively associated with total scores on the MWQ (p=0.02). These two inattention items had the strongest association with the MWQ (rs=0.45, df=38, p=0.004). ROC analyses showed that the combined score of the two significant inattention items had the highest efficiency (AUC=0.71) in classifying high-level mind wanderers as defined by scores greater than the median split on the MWQ. The combined score of the two inattention items best identified high-level mind wanderers.
Results suggest a way to operationalise mind wandering using the symptoms of ADHD.
Researchers have studied psychological disorders extensively from a common cause perspective, in which symptoms are treated as independent indicators of an underlying disease. In contrast, the causal systems perspective seeks to understand the importance of individual symptoms and symptom-to-symptom relationships. In the current study, we used network analysis to examine the relationships between and among depression and anxiety symptoms from the causal systems perspective.
We utilized data from a large psychiatric sample at admission and discharge from a partial hospital program (N = 1029, mean treatment duration = 8 days). We investigated features of the depression/anxiety network including topology, network centrality, stability of the network at admission and discharge, as well as change in the network over the course of treatment.
Individual symptoms of depression and anxiety were more related to other symptoms within each disorder than to symptoms between disorders. Sad mood and worry were among the most central symptoms in the network. The network structure was stable both at admission and between admission and discharge, although the overall strength of symptom relationships increased as symptom severity decreased over the course of treatment.
Examining depression and anxiety symptoms as dynamic systems may provide novel insights into the maintenance of these mental health problems.
The B type star 53 Persei was discovered in 1977 by Smith (1977) as the prototype of a separate group of B-type variables showing light and line profile variability. The physical cause of the variability was thought to be nonradial pulsation (NRP) (see, e.g. Smith et al. 1984). However, the NRP model for this star has been questioned by Balona (1986) who suggested the rotational modulation (RM) model to explain the variability. In order to resolve the long lasting debate about 53 Persei, a campaign was initiated to organize coordinated optical photometry and spectroscopy from the ground, and Far-UV photometry from Voyager in 1991 January. This paper presents the results of period analysis on the groundbased UBV data. In another paper, Smith & Huang (1994) report the new identification of pulsation modes using Voyager Far-UV photometry combined with the results from optical observations. Some preliminary results from APT uvby observations taken at a single site are also cited for comparison.
Omicron Andromedae is a multiple system of at least four stars: a B ↔Be star (component A), a spectroscopic binary (components B1–B2) and a close companion (component a). According to several studies (see Hill et al. 1988, 1989):
-the distance between A and the B1–B2 system decreased from 0.39″ in 1975 to 0.25″ in 1987 (McAlister and Hartkopf 1988)
-the few previous speckle measurements of component a have shown the possibility of a 3.7 years orbit around A, according to the 1975 to 1984 observations (mean distance 0.05″). The calculations with this 3.7 yr orbit lead to the prediction of a maximum distance of 0.77″ at 1992.738, i.e. at the end of september 1992, with a North-South orientation.
The Calar Alto Deep Imaging Survey (CADIS) combines deep multicolor imaging in broad and narrow band filters with deep probing in several selected wavelength intervals through a Fabry-Pérot (FP) interferometer with a spectral resolution of ∼450.
Neighboring tidewater glaciers often exhibit asynchronous dynamic behavior, despite relatively uniform regional atmospheric and oceanic forcings. This variability may be controlled by a combination of local factors, including glacier and fjord geometry, fjord heat content and circulation, and glacier surface melt. In order to characterize and understand contrasts in adjacent tidewater glacier and fjord dynamics, we made coincident ice-ocean-atmosphere observations at high temporal resolution (minutes to weeks) within a 10 000 km2 area near Uummannaq, Greenland. Water column velocity, temperature and salinity measurements reveal systematic differences in neighboring fjords that imply contrasting circulation patterns. The observed ocean velocity and hydrography, combined with numerical modeling, suggest that subglacial discharge plays a major role in setting fjord conditions. In addition, satellite remote sensing of seasonal ice flow speed and terminus position reveal both speedup and slow-down in response to melt, as well as differences in calving style among the neighboring glaciers. Glacier force budgets and modeling also point toward subglacial discharge as a key factor in glacier behavior. For the studied region, individual glacier and fjord geometry modulate subglacial discharge, which leads to contrasts in both fjord and glacier dynamics.
On May 22, 1989 the Japanese Ginga Team discovered a new X-ray source that was cataloged as GS 2023+338. This source was subsequently identified as coincident in position with a previously known nova cataloged as V404 Cygni. Its last recorded outburst was in 1938 when it rose to about 12th mag. Spectroscopic data were obtained and confirmed the nature of the outburst. Additional ground based data were obtained by us at CTIO and the VLA. The X-ray behavior of this object has been reported to be very unusual and it reached a peak of about 17 crab about one week after discovery. Since then it has varied widely in magnitude at all wavelengths at which it has been studied. We present a brief summary of the observations that have been obtained up to the time of the meeting and shortly thereafter.
To assess the effect of the Dutch school-based education programme ‘Taste Lessons’ on children’s behavioural determinants towards tasting unfamiliar foods and eating healthy and a variety of foods.
In a quasi-experimental study design, data on behavioural determinants were collected at baseline, four weeks and six months after the intervention in both the intervention and control group. Children completed consecutively three questionnaires in which knowledge, awareness, skills, attitude, emotion, subjective norm and intention towards the two target behaviours were assessed. Teachers implemented on average a third of the programme activities. Multilevel regression analyses were conducted to compare individual changes in the determinants in the intervention group with those in the control group, corrected for children’s gender and age. Effect sizes were expressed as Cohen’s d.
Dutch elementary schools.
Forty-nine classes (1183 children, 9–12 years old) in grades 5–8 of twenty-one elementary schools.
The intervention group showed a higher increase in knowledge (d=0·26, P<0·01), which persisted after six months (d=0·23, P<0·05). After four weeks, the intervention group showed a higher increase in number of foods known (d=0·22, P<0·05) and tasted (d=0·21, P<0·05), subjective norm of the teacher (d=0·17, P<0·05) and intention (d=0·16, P<0·05) towards the target behaviours.
Partial implementation of Taste Lessons during one school year showed small short-term effects on increasing behavioural determinants in relation to tasting unfamiliar foods and eating healthy and a variety of foods. Full and repeated implementation of Taste Lessons in subsequent years might result in larger effects.
In the present study, we analyse the effect of glycosylation in Echinostoma caproni (Trematoda: Echinostomatidae) antigens in antibody responses against the parasite in experimentally infected mice. It has been previously demonstrated that the mouse is a host of high compatibility with E. caproni and develops elevated responses of IgG, IgG1, IgG3 and IgM as a consequence of the infection, though the role of glycans in these responses remains unknown. To this purpose, the responses generated in mice against non-treated excretory/secretory antigens of E. caproni were compared with those observed after N-deglycosylation, O-deglycosylation and double deglycosylation of the antigens by indirect ELISA and western blot. Our results suggest that E. caproni-expressed glycans play a major role in the modulation of the immune responses. The results obtained indicate that IgG subclass responses generated in mice against E. caproni are essentially due to glycoproteins and may affect the Th1/Th2 biasing. The reactivity significantly decreased after any of the deglycosylation treatments and the N-glycans appears to be of greater importance than O-glycans. Interestingly, the IgM response increased after N-deglycosylation suggesting that carbohydrates may mask peptide antigens.
In this work we have developed optical models for the ellipsometric characterization of Bi-implanted CdTe. We have characterized the amount and nature of disorder using Rutherford Backscattering Spectrometry combined with channeling (RBS/C). Samples with a systematically varying degree of disorder were prepared using ion implantation of Bi into single-crystalline CdTe at an energy of 350 keV with increasing doses from 3.75×1013 cm-2 to 6×1014 cm−2. The motivation for use of the high atomic mass Bi ions was that previous studies using lighter ions revealed damage at a low level, even for doses several times higher than the amorphization threshold estimated by simulation [P. Petrik et al., phys. stat. sol. (c) 5, 1358 (2008)]. In contrast, Bi ions create sufficient disorder for investigation of the changes in dielectric function critical point (CP) features in a wider variety of structures from single-crystalline to the disordered state. The CP features can be described by numerous methods starting from the standard CP model, through the parameterization of Adachi [Adachi et al., J. Appl. Phys. 74, 3435 (1993)], and finally to the generalized CP models. The standard CP model has been demonstrated to be a reliable approach for polycrystalline CdTe characterization used in photovoltaic applications [Li et al., phys. stat. sol. (a) 205, 901 (2008)].
The quantum efficiency of electroluminescence (EL) in porous silicon structures (PSL) is practically limited by the mechanical instability of higher porosity layers. This can be overcome by adding a thin implanted p+ surface region before the formation of PSL. The resulting structure consisted of different morphologies depending on the local doping level. When the implantation doping level and diffusion depth was increased, reduced photoluminescence (PL) from the otherwise strongly emitting buried PSL of 80% porosity was obtained. Spectroscopic ellipsometry provided detailed analysis of optical transmission of PSL prepared on a boron implanted substrate. Since the spectral transmission of PSL is morphology dependent, in this novel structure the excitation wavelength can be absorbed in the upper mesoporous p+ region, which is much more transparent for the visible emission spectrum. The width and peak position as well as integral intensity of EL spectra during anodic oxidation of the novel, workable structure were not affected by the doping level in the thin surface region.
One of the applications of high dose ion implantation is to form surface
alloys or compound layers. The detailed characterization of such composite
structures is of great importance. This paper tries to answer the question:
how can we outline, at least, a qualitative picture from the optical
properties measured by ellipsometry of high dose Al and Sb implanted
silicon. Attempts are done to separate the effect of implanted impurities
from the dominant disorder contribution to the measured optical properties.
As the ellipsometry does not provide information enough to decide the
applicability of optical models therefore methods sensitive to the structure
(channeling and TEM) were applied too.
Chemical and mechanical stability of porous silicon layers (PSL) is the prerequisite of any active (luminescent) or passive (e.g. porous substrate) integrated applications. In this work X-ray diffraction (XRD) was used to analyze quantitatively the strain distribution obtained in different morphology PSL that were prepared on (100) p and p+Si substrates. Tetragonal lattice constant distortion can be as high as 1.4% in highly porous “as-prepared” samples. Incoherent optical heating RTO is governed by the absorption in the oxidized specimen. PSL show vertical inhomogeneity according to interpretation of spectroscopic ellipsometry (SE) data. Oxygen incorporation during RTO is controlled by specific surface (in p+ proportional, in p inversely proportional with porosity), while the developing compressive stress depends on pore size, and decreases with porosity in both morphologies.