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Universal screening for postpartum depression is recommended in many countries. Knowledge of whether the disclosure of depressive symptoms in the postpartum period differs across cultures could improve detection and provide new insights into the pathogenesis. Moreover, it is a necessary step to evaluate the universal use of screening instruments in research and clinical practice. In the current study we sought to assess whether the Edinburgh Postnatal Depression Scale (EPDS), the most widely used screening tool for postpartum depression, measures the same underlying construct across cultural groups in a large international dataset.
Ordinal regression and measurement invariance were used to explore the association between culture, operationalized as education, ethnicity/race and continent, and endorsement of depressive symptoms using the EPDS on 8209 new mothers from Europe and the USA.
Education, but not ethnicity/race, influenced the reporting of postpartum depression [difference between robust comparative fit indexes (∆*CFI) < 0.01]. The structure of EPDS responses significantly differed between Europe and the USA (∆*CFI > 0.01), but not between European countries (∆*CFI < 0.01).
Investigators and clinicians should be aware of the potential differences in expression of phenotype of postpartum depression that women of different educational backgrounds may manifest. The increasing cultural heterogeneity of societies together with the tendency towards globalization requires a culturally sensitive approach to patients, research and policies, that takes into account, beyond rhetoric, the context of a person's experiences and the context in which the research is conducted.
Magnetic resonance imaging studies of maltreated children with posttraumatic stress disorder (PTSD) suggest that maltreatment-related PTSD is associated with adverse brain development. Maltreated youth resilient to chronic PTSD were not previously investigated and may elucidate neuromechanisms of the stress diathesis that leads to resilience to chronic PTSD. In this cross-sectional study, anatomical volumetric and corpus callosum diffusion tensor imaging measures were examined using magnetic resonance imaging in maltreated youth with chronic PTSD (N = 38), without PTSD (N = 35), and nonmaltreated participants (n = 59). Groups were sociodemographically similar. Participants underwent assessments for strict inclusion/exclusion criteria and psychopathology. Maltreated youth with PTSD were psychobiologically different from maltreated youth without PTSD and nonmaltreated controls. Maltreated youth with PTSD had smaller posterior cerebral and cerebellar gray matter volumes than did maltreated youth without PTSD and nonmaltreated participants. Cerebral and cerebellar gray matter volumes inversely correlated with PTSD symptoms. Posterior corpus callosum microstructure in pediatric maltreatment-related PTSD differed compared to maltreated youth without PTSD and controls. The group differences remained significant when controlling for psychopathology, numbers of Axis I disorders, and trauma load. Alterations of these posterior brain structures may result from a shared trauma-related mechanism or an inherent vulnerability that mediates the pathway from chronic PTSD to comorbidity.
In the United States alone, ∼14,000 children are hospitalised annually with acute heart failure. The science and art of caring for these patients continues to evolve. The International Pediatric Heart Failure Summit of Johns Hopkins All Children’s Heart Institute was held on February 4 and 5, 2015. The 2015 International Pediatric Heart Failure Summit of Johns Hopkins All Children’s Heart Institute was funded through the Andrews/Daicoff Cardiovascular Program Endowment, a philanthropic collaboration between All Children’s Hospital and the Morsani College of Medicine at the University of South Florida (USF). Sponsored by All Children’s Hospital Andrews/Daicoff Cardiovascular Program, the International Pediatric Heart Failure Summit assembled leaders in clinical and scientific disciplines related to paediatric heart failure and created a multi-disciplinary “think-tank”. The purpose of this manuscript is to summarise the lessons from the 2015 International Pediatric Heart Failure Summit of Johns Hopkins All Children’s Heart Institute, to describe the “state of the art” of the treatment of paediatric cardiac failure, and to discuss future directions for research in the domain of paediatric cardiac failure.
Papillary microcarcinoma of the thyroid has been described as either a normal variant or a serious malignancy. We describe our experience with papillary microcarcinoma and lymph node metastases.
A total of 685 consecutive total thyroidectomies with central compartment neck dissection were reviewed for papillary microcarcinoma. Association of central compartment lymph node metastases with age, gender, tumour multifocality, bilaterality and extrathyroidal extension was analysed.
Out of 170 papillary microcarcinoma cases, multifocality was found in 72 (42.4 per cent), bilaterality in 49 (28.8 per cent) and extrathyroidal extension in 16 (9.4 per cent). In all, 23 patients (13.5 per cent) had lymph node metastases. There was a significant association (p < 0.05) between extrathyroidal extension (but no other tumour characteristics) and lymph node metastases.
In all, 13.5 per cent of papillary microcarcinomas in our series showed lymph node metastases. Lymph node metastases were associated with extrathyroidal invasion of the papillary microcarcinoma.
The spread of coagulase-positive staphylococci has been studied in a modern hospital in which most of the patients were nursed in 4-bed rooms separated from a common corridor only by low dividing walls. Acquisition of new nasal strains from patients in other bedrooms was nearly as easy as from patients in the neighbouring beds. There was no indication that subdivision of this type hindered the spread of nasal strains as compared with open wards of the ‘Nightingale’ pattern.
Samples of yellow-fever vaccine prepared from homogenized chick embryos, and of an experimental measles vaccine prepared from chick embryo cells, have each been shown to contain a contaminant virus similar in properties to an avian leukosis virus. Young adult males injected with the yellow-fever vaccine did not develop neutralizing antibodies for Rous sarcoma virus.
The NASA Star and Exoplanet Database (NStED) is a general purpose stellar archive with the aim of providing support for NASA's planet finding and characterization goals, stellar astrophysics, and the planning of NASA and other space missions. There are two principal components of NStED: a database of (currently) 140,000 nearby stars and exoplanet-hosting stars, and an archive dedicated to high precision photometric surveys for transiting exoplanets. We present a summary of the NStED stellar database, functionality, tools, and user interface. NStED currently serves the following kinds of data for 140,000 stars (where available): coordinates, multiplicity, proper motion, parallax, spectral type, multiband photometry, radial velocity, metallicity, chromospheric and coronal activity index, and rotation velocity/period. Furthermore, the following derived quantities are given wherever possible: distance, effective temperature, mass, radius, luminosity, space motions, and physical/angular dimensions of habitable zone. Queries to NStED can be made using constraints on any combination of the above parameters. In addition, NStED provides tools to derive specific inferred quantities for the stars in the database, cross-referenced with available extra-solar planetary data for those host stars. NStED can be accessed at http://nsted.ipac.caltech.edu.
The NASA Star and Exoplanet Database (NStED) is a general purpose stellar archive with the aim of providing support for NASA's planet finding and characterization goals, stellar astrophysics, and the planning of NASA and other space missions. There are two principal components of NStED: a database of (currently) 140,000 nearby stars and exoplanet-hosting stars, and an archive dedicated to high-precision photometric surveys for transiting exoplanets. We present a summary of the latter component: the NStED Exoplanet Transit Survey Service (NStED-ETSS), along with its content, functionality, tools, and user interface. NStED-ETSS currently serves data from the TrES Survey of the Kepler Field as well as dedicated photometric surveys of four stellar clusters. NStED-ETSS aims to serve both the surveys and the broader astronomical community by archiving these data and making them available in a homogeneous format. Examples of usability of ETSS include investigation of any time-variable phenomena in data sets not studied by the original survey team, application of different techniques or algorithms for planet transit detections, combination of data from different surveys for given objects, statistical studies, etc. NStED-ETSS can be accessed at http://nsted.ipac.caltech.edu.
Chemical extraction techniques and scanning electron microscopy were used to study the distribution and behavior of actinides and rare earth elements (REE) in hydrothermal veins at Adamello, (Italy). The six samples discussed in this paper were from the phlogopite zone, which is one of the major vein zones. The samples were similar in their bulk chemical composition, mineralogy, and leaching behavior of major elements (determined by extraction with 9M HCl). However, there were major differences in the extractability of REE and actinides. The most significant influence on the leaching characteristics appears to be the amounts of U, Th and REE incorporated in resistant host phases. Uranium and Th are very highly enriched in zirconolite grains. Actinides were more readily leached from samples with a higher content of U and Th, relative to the amount of zirconolite. The results show that REE and actinides present in chemically resistant minerals can be retained under aggressive leaching conditions.
Periodic axisymmetric vortex breakdown in a cylinder with a rotating end wall
When the fluid inside a completely filled cylinder is set in motion by the rotation of the bottom end wall, steady and unsteady axisymmetric vortex breakdown is possible. The onset of unsteadiness is via a Hopf bifurcation.
Figure 1 is a perspective view of the flow inside the cylinder where marker particles have been released from an elliptic ring concentric with the axis of symmetry near the top end wall. This periodic flow corresponds to a Reynolds number Re=2765 and cylinder aspect ratio H/R=2.5. Neighboring particles have been grouped to define a sheet of marker fluid and the local transparency of the sheet has been made proportional to its local stretching. The resultant dye sheet takes on an asymmetric shape, even though the flow is axisymmetric, due to the unsteadiness and the asymmetric release of marker particles.When the release is symmetric, as in Fig. 2, the dye sheet is also symmetric. These two figures are snapshots of the dye sheet after three periods of the oscillation (a period is approximately 36.3 rotations of the end wall). Figure 3 is a cross section of the dye sheet in Fig. 2 after 26 periods of the oscillation. Here only the marker particles are shown. They are colored according to their time of release, the oldest being blue, through green and yellow, and the most recently released being red. Comparison with Escudier's experiment shows very close agreement.
The particle equations of motion correspond to a Hamiltonian dynamical system and an appropriate.
The AS/AGU rat provides an alternative to experimentally produced laboratory models of basal ganglia
disorders. This mutant is characterised by disturbances of movement including clumsy gait, whole body
tremor, rigidity and difficulty in initiating movement. From an early age, there is a profound depletion of
extracellular dopamine in the dorsal caudate-putamen as measured via in vivo microdialysis; levels are only
10–20% of those found in the parent Albino Swiss (AS) strain. Subsequently a depletion of whole tissue
dopamine levels occurs and, later still, loss of dopaminergic cells in the substantia nigra pars compacta. The
dysfunction in movement and the nigrostriatal dopaminergic system are clearly linked, since movement can
be ameliorated by L-DOPA administration. Furthermore, there are depletions in glucose utilisation in several
regions of the basal ganglia circuitry, including the substantia nigra pars compacta, the subthalamic nucleus
and the ventrolateral thalamus. The AS/AGU rat represents a unique opportunity to investigate the
intrinsic factors controlling the integrity of dopaminergic systems and the recent successful positional cloning
of the agu gene will allow the molecular mechanisms underlying this interesting phenotype to be analysed.
This paper discusses results from the second phase of the European Ice Sheet Modelling Initiative (EISMINT). It reports the intercomparison of ten operational ice-sheet models and uses a series of experiments to examine the implications of thermomechanical coupling for model behaviour. A schematic, circular ice sheet is used in the work which investigates both steady states and the response to stepped changes in climate. The major finding is that the radial symmetry implied in the experimental design can, under certain circumstances, break down with the formation of distinct, regularly spaced spokes of cold ice which extended from the interior of the ice sheet outward to the surrounding zone of basal melt. These features also manifest themselves in the thickness and velocity distributions predicted by the models. They appear to be a common feature to all of the models which took part in the intercomparison, and may stem from interactions between ice temperature, flow and surface form. The exact nature of these features varies between models, and their existence appears to be controlled by the overall thermal regime of the ice sheet. A second result is that there is considerable agreement between the models in their predictions of global-scale response to imposed climate change.
Betafite and zirconolite occur in Ti-rich hydrothermal veins emplaced within dolomite marble in the contact aureole of the Adamello batholith, northern Italy. Zirconolite contains up to 18 wt% ThO2 and 24 wt% UO2, and exhibits strong compositional zoning. Some zirconolite grains were corroded by the hydrothermal fluid. Betafite, the Ti-rich member of the pyrochlore group, often occurs as overgrowths on zirconolite. The betafite is weakly zoned and contains 29-34 wt% UO2. In terms of end -members, betafite contains approximately 50 mole percent CaUTi2O7 and is the closest known natural composition to the pyrochlore phase proposed for use in titanate waste forms. Amorphization and volume expansion of the betafite caused cracks to form in the enclosing silicate mineral grains. Backscattered electron images reveal that betafite was subsequently altered along crystal rims, particularly near the cracks. EPMA data reveal little difference in composition between altered and unaltered areas, except for lower totals, suggesting that alteration is primarily due to hydration. The available evidence demonstrates that both betafite and zirconolite retained actinides for approximately 40 million years after the final stage of vein formation. During this time, betafite and zirconolite accumulated a total alpha -decay dose of 3-4 x 1016 and 0.2-2 x 1016 α/mg, respectively.
We studied the magnetic and electronic transport properties of a single crystal sample of La0.64Pb0.36MnO3 in the temperature range 5 K to 350 K and magnetic field up to 5.5 T. A magnetic transition is found at 210 K. The single crystal sample is ferromagnetic below the transition temperature (Tc) and becomes paramagnetic at temperatures T > Tc. Magnetization measurements along three different orthorhombic crystal axes show no significant difference. The magnetoresistance approaches a maximum value of about -60% at Tc in 5 T magnetic field strength and has qualitatively different field dependence below and above Tc. The scaling behavior between resistivity and magnetic moment is examined for temperatures both below and above the transition. A low temperature (T<15 K) dp / dT < 0 effect is attributed to possible quantum tunneling of carriers between neighbouring distortions.
Self assembled monolayers patterned by microcontact printing have been used in conjunction with sol-gel processing to selectively deposit oxide thin films with micron-scale lateral resolution. This simple, three step process allows ambient, lithography-free patterning of oxide thin films for integrated microelectronics, optoelectronics, and sensor applications. A variety of patterned structures, such as capacitors and waveguides, have been fabricated from LiNbO3, Ta2O5, PbTiO3, and BaTiO3 on technologically important substrates, including Si, Al, Pt, sapphire, and TiN. The technique involves functionalization of substrate surfaces by microcontact printing of octadecyltrichlorosilane (OTS) self-assembled monolayers (SAMs). Sol-gel precursors are then spin-coated on the SAMs-patterned surfaces and heat treated to deposit 20 nm-300 nm amorphous oxide layers. Oxide on derivatized regions is removed with mild polishing, yielding patterned films with features as small as 5 μm. For example, data are reported for 80–200nm Ta2O5 films to demonstrate the potential applications and mechanisms involved. The effects of sol-gel precursor chemistry, heat treatment, and other processing variables are reported. These results suggest unique potential for microfabrication of ceramic thin films using molecular self assembly and low temperature processing of solution-derived thin films.
Total-Energy pseudopotential calculations are used to study both the onset and development of plasticity in nanoindentation experiments and the contrast mechanism in non-contact AFM images on Si (111) surfaces. As regards nanoindentation, plastic flow of atoms towards interstitial positions and extrusion of material towards the tip walls, stabilized by the adhesive interactions with the tip, are the dominant mechanisms. These plastic deformations are triggered by the delocalization of the charge induced by the stress in the elastically compressed structure. Atomic resolution contrast in AFM is shown to be clearly enhanced by the partial covalent chemical interaction between the dangling bonds of the adatoms in the surface and the apex atom in the tip. The contrast mechanism can be understood in terms of the coupling between the tip and the charge transfer modes among the different dangling bonds in the surface.