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Why does early childhood deprivation increase the risk for depression and anxiety in adulthood? A developmental cascade model
Abstract Background: Using data from the English & Romanian Adoptees (ERA) study we recently reported that early time-lmited exposure to severe institutional deprivation is
associated with early onset and persistent neurodevelopmental problems and later
onset emotional problems. Here we examine possible reasons for the late
emergence of emotional problems in this cohort. Our main focus is on testing a
developmental cascade mediated via the functional impact of early-appearing
neurodevelopmental problems on late adolescent functioning. We also explore a
second putative pathway via sensitization to stress. Methods: The ERA study includes 165 Romanian individuals who spent their early lives in grossly depriving institutions and were subsequently adopted into UK
families, along with 52 UK adoptees with no history of deprivation. Age six years
symptoms of neurodevelopmental problems and age 15 anxiety/depression
symptoms were assessed via parental reports. Young adult symptoms of depression
and anxiety were assessed by both parent and self-reports; young adults also
completed measures of stress reactivity , exposure to adverse life events and
functioning in work and interpersonal relationships. Results: The path between early institutional deprivation and adult emotional problems was mediated via the impact of early neurodevelopmental problems on
unemployment and poor friendship functioning during the transition to adulthood.
The findings with regard to early deprivation, later life stress reactivity and emotional
problems were inconclusive.
Conclusions: Our analysis suggests that the risk for adult depression and anxiety following extreme institutional deprivation is explained through the effects of early neurodevelopmental problems on later social and vocational functioning. Future research should more fully examine the role of stress susceptibility in this model
The Anatomy of an Unusual Edge-on Protoplanetary Disk. II. Gas temperature and a warm outer region
We present high-resolution CO and CO 2-1 ALMA observations, as
well as optical and near-infrared spectroscopy, of the highly-inclined
protoplanetary disk around SSTC2D J163131.2-242627. The spectral type we derive
for the source is consistent with a star inferred from
the ALMA observations. Despite its massive circumstellar disk, we find little
to no evidence for ongoing accretion on the star. The CO maps reveal a disk
that is unusually compact along the vertical direction, consistent with its
appearance in scattered light images. The gas disk extends about twice as far
away as both the submillimeter continuum and the optical scattered light. CO is
detected from two surface layers separated by a midplane region in which CO
emission is suppressed, as expected from freeze-out in the cold midplane. We
apply a modified version of the Topographically Reconstructed Distribution
method presented by Dutrey et al. 2017 to derive the temperature structure of
the disk. We find a temperature in the CO-emitting layers and the midplane of
33 K and 20 K at au, respectively. Outside of au, the disk's midplane temperature increases to 30 K, with a
nearly vertically isothermal profile. The transition in CO temperature
coincides with a dramatic reduction in the sub-micron and sub-millimeter
emission from the disk. We interpret this as interstellar UV radiation
providing an additional source of heating to the outer part of the disk.Comment: 27 pages, 18 figures, 1 tabl
Persistent influence of obliquity on ice age terminations since the Middle Pleistocene transition.
Radiometric dating of glacial terminations over the past 640,000 years suggests pacing by Earth's climatic precession, with each glacial-interglacial period spanning four or five cycles of ~20,000 years. However, the lack of firm age estimates for older Pleistocene terminations confounds attempts to test the persistence of precession forcing. We combine an Italian speleothem record anchored by a uranium-lead chronology with North Atlantic ocean data to show that the first two deglaciations of the so-called 100,000-year world are separated by two obliquity cycles, with each termination starting at the same high phase of obliquity, but at opposing phases of precession. An assessment of 11 radiometrically dated terminations spanning the past million years suggests that obliquity exerted a persistent influence on not only their initiation but also their duration
Evidence for a High Carbon Abundance in the Local Interstellar Cloud
The nature of the Local Interstellar Cloud (LIC) is highly constrained by the
combination of in situ heliospheric and line-of-sight data towards nearby
stars. We present a new interpretation of the LIC components of the absorption
line data towards epsilon CMa, based on recent atomic data that include new
rates for the Mg+ to Mg0 dielectronic recombination rate, and using in situ
measurements of the temperature and density of neutral helium inside of the
heliosphere. With these data we are able to place interesting limits on the gas
phase abundance of carbon in the LIC. If the C/S abundance ratio is solar, ~20,
then no simultaneous solution exists for the N(Mg I), N(Mg II), N(C II) and N(C
II*) data. The combined column density and in situ data favor an abundance
ratio A(C)/A(S) = 47 +22 -26.
We find that the most probable gas phase C abundance is in the range 400 to
800 ppm with a lower limit of ~330. We speculate that such a supersolar
abundance could have come to be present in the LIC via destruction of decoupled
dust grains. Similar enhanced C/H ratios are seen in very low column density
material, N(H) < 10^19 cm^-2, towards several nearby stars.Comment: 11 pages, 1 figure, Accepted for publication in ApJ Letter
The Computational Complexity of Generating Random Fractals
In this paper we examine a number of models that generate random fractals.
The models are studied using the tools of computational complexity theory from
the perspective of parallel computation. Diffusion limited aggregation and
several widely used algorithms for equilibrating the Ising model are shown to
be highly sequential; it is unlikely they can be simulated efficiently in
parallel. This is in contrast to Mandelbrot percolation that can be simulated
in constant parallel time. Our research helps shed light on the intrinsic
complexity of these models relative to each other and to different growth
processes that have been recently studied using complexity theory. In addition,
the results may serve as a guide to simulation physics.Comment: 28 pages, LATEX, 8 Postscript figures available from
[email protected]
The relationship of smoking and unhealthy alcohol use to the HIV care continuum among people with HIV in an integrated health care system
INTRODUCTION: Smoking tobacco and unhealthy alcohol use may negatively influence HIV care continuum outcomes but have not been examined in combination. METHODS: Participants were people with HIV (PWH) in Kaiser Permanente Northern California. Predictors included smoking status and unhealthy alcohol use (exceeding daily and/or weekly limits) reported by patients during primary care screening (index date). Outcomes were based on not achieving the following steps in the care continuum: linkage to HIV care (≥1 visit within 90 days of newly identified HIV diagnosis), retention (2+ in-person visits, 60+ days apart) and HIV RNA control (<75 copies/mL). Adjusted odds ratios (ORs) were obtained from separate logistic regression models for each outcome associated with smoking and unhealthy alcohol use independently and combined. RESULTS: The overall sample (N=8,958) had a mean age of 48.0 years; was 91.3% male; 54.0% white, 17.6% Latino, 15.1% black, and 9.6% other race/ethnicity. Smoking was associated with higher odds of not being linked to HIV care (OR=1.60 [95% CI 1.03–2.48]), not retained (OR=1.30 [95% CI 1.13–1.50]), and HIV RNA not in control (OR=1.91 [95% CI 1.60–2.27]). Alcohol measures were not independently associated with outcomes. The combination of unhealthy alcohol use and smoking (versus neither) was associated with higher odds of not being linked to care (OR=2.83 [95% CI 1.40–5.71]), although the interaction did not reach significance (p=0.18). CONCLUSIONS: In this large sample of PWH in an integrated health care system, smoking, both independently and in combination with unhealthy alcohol use, was associated with worse HIV care continuum outcomes
GPI spectra of HR 8799 c, d, and e from 1.5 to 2.4m with KLIP Forward Modeling
We explore KLIP forward modeling spectral extraction on Gemini Planet Imager
coronagraphic data of HR 8799, using PyKLIP and show algorithm stability with
varying KLIP parameters. We report new and re-reduced spectrophotometry of HR
8799 c, d, and e in H & K bands. We discuss a strategy for choosing optimal
KLIP PSF subtraction parameters by injecting simulated sources and recovering
them over a range of parameters. The K1/K2 spectra for HR 8799 c and d are
similar to previously published results from the same dataset. We also present
a K band spectrum of HR 8799 e for the first time and show that our H-band
spectra agree well with previously published spectra from the VLT/SPHERE
instrument. We show that HR 8799 c and d show significant differences in their
H & K spectra, but do not find any conclusive differences between d and e or c
and e, likely due to large error bars in the recovered spectrum of e. Compared
to M, L, and T-type field brown dwarfs, all three planets are most consistent
with mid and late L spectral types. All objects are consistent with low gravity
but a lack of standard spectra for low gravity limit the ability to fit the
best spectral type. We discuss how dedicated modeling efforts can better fit HR
8799 planets' near-IR flux and discuss how differences between the properties
of these planets can be further explored.Comment: Accepted to AJ, 25 pages, 16 Figure
Magnetic resonance imaging for the differentiation of neoplastic, inflammatory, and cerebrovascular brain disease in dogs
BACKGROUND: The reliability and validity of magnetic resonance imaging (MRI) for detecting neoplastic, inflammatory, and cerebrovascular brain lesions in dogs are unknown. OBJECTIVES: To estimate sensitivity, specificity, and inter-rater agreement of MRI for classifying histologically confirmed neoplastic, inflammatory, and cerebrovascular brain disease in dogs. ANIMALS: One hundred and twenty-one client-owned dogs diagnosed with brain disease (n = 77) or idiopathic epilepsy (n = 44). METHODS: Retrospective, multi-institutional case series; 3 investigators analyzed MR images for the presence of a brain lesion with and without knowledge of case clinical data. Investigators recorded most likely etiologic category (neoplastic, inflammatory, cerebrovascular) and most likely specific disease for all brain lesions. Sensitivity, specificity, and inter-rater agreement were calculated to estimate diagnostic performance. RESULTS: MRI was 94.4% sensitive (95% confidence interval [CI] = 88.7, 97.4) and 95.5% specific (95% CI = 89.9, 98.1) for detecting a brain lesion with similarly high performance for classifying neoplastic and inflammatory disease, but was only 38.9% sensitive for classifying cerebrovascular disease (95% CI = 16.1, 67.0). In general, high specificity but not sensitivity was retained for MR diagnosis of specific brain diseases. Inter-rater agreement was very good for overall detection of structural brain lesions (j = 0.895, 95% CI = 0.792, 0.998, P < .001) and neoplastic lesions, but was only fair for cerebrovascular lesions (j = 0.299, 95% CI = 0, 0.761, P = .21). CONCLUSIONS AND CLINICAL IMPORTANCE: MRI is sensitive and specific for identifying brain lesions and classifying disease as inflammatory or neoplastic in dogs. Cerebrovascular disease in general and specific inflammatory, neoplastic, and cerebrovascular brain diseases were frequently misclassified.http://onlinelibrary.wiley.com/journal/10.1111/(ISSN)1939-1676ab201
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