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Few studies have examined functional connectivity (FC) patterns using functional magnetic resonance imaging (fMRI) to predict outcomes in late-life depression. We hypothesized that FC within and between frontal and limbic regions would be associated with 12-week depression outcome in older depressed adults. Seventy-one subjects with major depression were enrolled in the study. A study geriatric psychiatrist performed a clinical interview and completed a Montgomery-Åsberg Depression Rating Scale (MADRS). All study participants were free of medication at baseline and had a brain fMRI scan. Using a regions of interest (ROI) atlas (including 164 ROIs), we conducted ROI-to-ROI resting-state FC analyses for each participant. In terms of treatment participants were offered sertraline initially, although in this naturalistic study, other medications were also prescribed. Subjects were evaluated every 2 weeks up to 12 weeks by the study psychiatrist, who followed a flexible, clinically based medication dosing schedule. Multivariate regression analysis was used to examine correlation between change of MADRS score over 12 weeks and baseline FC between brain regions, controlling for age, gender, mean head motion, and baseline MADRS. We found greater FC between the left inferior frontal gyrus pars triangularis and the left frontal eye field and FC of these two regions with a number of brain regions related to reward, salience, and sensorimortor function were correlated with change in MADRS score over 12 weeks. Our results highlight the important role of between inner speech-reward, attention-salience, and attention-sensorimotor network synchronization in predicting acute treatment response in late-life depression.
The Yellow Sea region is of high global importance for waterbird populations, but recent systematic bird count data enabling identification of the most important sites are relatively sparse for some areas. Surveys of waterbirds at three sites on the coast of southern Jiangsu Province, China, in 2014 and 2015 produced peak counts of international importance for 24 species, including seven globally threatened and six Near Threatened species. The area is of particular global importance for the ‘Critically Endangered’ Spoon-billed Sandpiper Calidris pygmaea (peak count across all three study sites: 62 in spring  and 225 in autumn  and ‘Endangered’ Spotted Greenshank Tringa guttifer (peak count across all three study sites: 210 in spring  and 1,110 in autumn ). The southern Jiangsu coast is therefore currently the most important migratory stopover area in the world, in both spring and autumn, for both species. Several serious and acute threats to waterbirds were recorded at these study sites. Paramount is the threat of large-scale land claim which would completely destroy intertidal mudflats of critical importance to waterbirds. Degradation of intertidal mudflat habitats through the spread of invasive Spartina, and mortality of waterbirds by entrapment in nets or deliberate poisoning are also real and present serious threats here. Collisions with, and displacement by, wind turbines and other structures, and industrial chemical pollution may represent additional potential threats. We recommend the rapid establishment of effective protected areas for waterbirds in the study area, maintaining large areas of open intertidal mudflat, and the urgent removal of all serious threats currently faced by waterbirds here.
The existence of black holes with masses of about one billion solar masses in quasars at redshifts z > 6 presents significant challenges to theories of the formation and growth of black holes and the black hole/galaxy co-evolution in the early Universe. Here we report a recent discovery of an ultra-luminous quasar at redshift z = 6.30, which has an observed optical and near-infrared luminosity a few times greater than those of previously known z > 6 quasars. With near-infrared spectroscopy, we obtain a black hole mass of about 12 billion solar masses, which is well consistent with the mass derived by assuming an Eddington-limited accretion. This ultra-luminous quasar with at z > 6 provides a unique laboratory to the study of the mass assembly and galaxy formation around the most massive black holes at cosmic dawn. It raises further challenges to the black hole/galaxy co-evolution in the epoch of cosmic reionization because the black hole needs to grow much faster than the host galaxy.
The recent development of in-situ liquid stages for (scanning) transmission electron microscopes now makes it possible for us to study the details of electrochemical processes under operando conditions. As electrochemical processes are complex, care must be taken to calibrate the system before any in-situ/operando observations. In addition, as the electron beam can cause effects that look similar to electrochemical processes at the electrolyte/electrode interface, an understanding of the role of the electron beam in modifying the operando observations must also be understood. In this paper we describe the design, assembly, and operation of an in-situ electrochemical cell, paying particular attention to the method for controlling and quantifying the experimental parameters. The use of this system is then demonstrated for the lithiation/delithiation of silicon nanowires.
Multi-functionalization of catalytically-active nanomaterials provides a valuable tool for enhancing reaction yield by shifting reaction equilibrium, and potentially also by adjusting reaction-diffusion kinetics. For example, multi-functionalization of mesoporous silica to make the interior pore surface hydrophobic can enhance yield in dehydration reactions. Detailed molecular-level modeling to describe the pore environment, as well as the reaction and diffusion kinetics is challenging, although we briefly discuss current strategies. Our focus, however, is on coarse-grained stochastic modeling of the overall catalytic process for highly restricted transport within narrow pores (with single-file diffusion), while accounting for a tunable interaction of the pore interior with reaction products. We show that making the pore interior unfavorable to products can significantly enhance yield due to both thermodynamic and kinetics factors.
Vertically aligned graphene was grown by plasma-enhanced chemical vapor deposition using methane feedstock. Optical emission spectroscopy (OES) was used to monitor the plasma species, and Raman spectroscopy was used for characterizing the properties of as-grown vertically aligned graphene. OES-derived information on plasma species, such as C, C2, CH, and H, are correlated with the properties of the vertically aligned graphene. Graphene grown at 250 W and 15 sccm exhibited the lowest amount of defects. Although OES peak intensities occurred at the highest power and lowest flow conditions, the OES peak ratios of plasma species had a greater dependence on flow rate and exhibited a saddle point in the atomic C/H ratio corresponding to optimal growth involving the lowest amount of overall defects. Plasma diagnostics provides a valuable approach to optimize growth characteristics and material properties.
Directional multiscale representations such as shearlets and curvelets have gained
increasing recognition in recent years as superior methods for the sparse representation
of data. Thanks to their ability to sparsely encode images and other multidimensional
data, transform-domain denoising algorithms based on these representations are among the
best performing methods currently available. As already observed in the literature, the
performance of many sparsity-based data processing methods can be further improved by
using appropriate combinations of dictionaries. In this paper, we consider the problem of
3D data denoising and introduce a denoising algorithm which uses combined sparse
dictionaries. Our numerical demonstrations show that the realization of the algorithm
which combines 3D shearlets and local Fourier bases provides highly competitive results as
compared to other 3D sparsity-based denosing algorithms based on both single and combined
The shearlet representation has gained increasing recognition in recent years as a
framework for the efficient representation of multidimensional data. This representation
consists of a countable collection of functions defined at various locations, scales and
orientations, where the orientations are obtained through the use of shear matrices. While
shear matrices offer the advantage of preserving the integer lattice and being more
appropriate than rotations for digital implementations, the drawback is that the action of
the shear matrices is restricted to cone-shaped regions in the frequency domain. Hence, in
the standard construction, a Parseval frame of shearlets is obtained by combining
different systems of cone-based shearlets which are projected onto certain subspaces of
L2(ℝD) with the consequence that
the elements of the shearlet system corresponding to the boundary of the cone regions lose
their good spatial localization property. In this paper, we present a new construction
yielding smooth Parseval frame of shearlets for
L2(ℝD). Specifically, all
elements of the shearlet systems obtained from this construction are compactly supported
and C∞ in the frequency domain, hence ensuring that the system
has also excellent spatial localization.
The authors present the technological routes used to build planar and vertical gate all-around (GAA) field-effect transistors (FETs) using both Si and SiGe nanowires (NWs) and the electrical performances of the as-obtained components. Planar FETs are characterized in back gate configuration and exhibit good behavior such as an ION/IOFF ratio up to 106. Hysteretic behavior and sub-threshold slope values with respect to surface and oxide interface trap densities are discussed. Vertical devices using Si NWs show good characteristics at the state of the art with ION/IOFF ratio close to 106 and sub-threshold slope around 125 mV/decade while vertical SiGe devices also obtained with the same technological processes, present an ION/IOFF ratio from 103 to 104but with poor dynamics which can be explained by the high interface traps density.
Objective: There is clear evidence of a genetic component in major depression, and several studies indicate that neuropeptide Y (NPY) could play an important role in the pathophysiology of the disease. A well-known polymorphism encoding the substitution of leucine to proline in the signal peptide sequence of NPY (Leu7Pro variation) was previously found to protect against depression. Our study aimed at replicating this association in a large Danish population with major depression.
Method: Leu7Pro was studied in a sample of depressed patients and ethnically matched controls, as well as psychiatric disease controls with schizophrenia. Possible functional consequences of Leu7Pro were explored in vitro.
Results: In contrast to previous studies, Pro7 appeared to be a risk allele for depression, being significantly more frequent in the depression sample (5.5%, n = 593; p = 0.009; odds ratio, OR: 1.46) as compared to ethnically matched controls (3.8%, n = 2912), while schizophrenia patients (4.1%, n = 503) did not differ. In vitro, the Pro7 substitution appeared to be associated with reduced levels of NPY without affecting its mRNA level.
Conclusion: The Leu7Pro variation may increase the risk of major depression, possibly by affecting the biosynthesis of NPY.