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Major depressive disorder (MDD) commonly co-occurs with clinically significant levels of anxiety. However, anxiety symptoms are varied and have been inconsistently associated with clinical, functional, and antidepressant treatment outcomes. We aimed to identify and characterise dimensions of anxiety in people with MDD and their use in predicting antidepressant treatment outcome.
1008 adults with a current diagnosis of single-episode or recurrent, nonpsychotic, MDD were assessed at baseline on clinical features and cognitive/physiological functioning. Participants were then randomised to one of three commonly prescribed antidepressants and reassessed at 8 weeks regarding symptom change, as well as remission and response, on the 17-item Hamilton Rating Scale Depression (HRSD17) and the 16-item Quick Inventory of Depressive Symptomatology (QIDS-SR16). Exploratory factor analysis was used on items from scales assessing anxiety symptoms, and resulting factors were assessed against clinical features and cognitive/physiological functioning. Factors were also assessed on their ability to predict treatment outcome.
Three factors emerged relating to stress, cognitive anxiety, and somatic anxiety. All factors showed high internal consistency, minimal cross-loadings, and unique clinical and functional profiles. Furthermore, only higher somatic anxiety was associated with poorer QIDS-SR16 remission, even after adjusting for covariates and multiple comparisons.
Anxiety symptoms in people with MDD can be separated onto distinct factors that differentially respond to treatment outcome. Furthermore, these factors do not align with subscales of established measures of anxiety. Future research should consider cognitive and somatic symptoms of anxiety separately when assessing anxiety in MDD and their use in predicting treatment outcome.
We present maps in the visible emission lines of [S II] and the infrared emission lines of H2, at 2.12μm, for several bipolar outflow complexes which exhibit jet structures. A comparison of the morphology of this infrared emission and that seen in visible emission lines shows both the visible and the H2 emission exhibit clumpy structure on similar scales. It appears that the brightest H2 emission occurs at the working surfaces of the jets. Virtually no H2 emission is associated with the jets themselves.
Velocity profiles are presented for several objects and possible emission mechanisms are discussed.
To determine what factors are associated with parental motivation to change body weight in overweight children.
Dunedin, New Zealand.
Two hundred and seventy-one children aged 4–8 years, recruited in primary and secondary care, were identified as overweight (BMI≥85th percentile) after screening. Parents completed questionnaires on demographics; motivation to improve diet, physical activity and weight; perception and concern about weight; parenting; and social desirability, prior to being informed that their child was overweight. Additional measures of physical activity (accelerometry), dietary intake and child behaviour (questionnaire) were obtained after feedback.
Although all children were overweight, only 42 % of parents perceived their child to be so, with 36 % indicating any concern. Very few parents (n 25, 8 %) were actively trying to change the child’s weight. Greater motivation to change weight was observed for girls compared with boys (P=0·001), despite no sex difference in BMI Z-score (P=0·374). Motivation was not associated with most demographic variables, social desirability, dietary intake, parenting or child behaviour. Increased motivation to change the child’s weight was observed for heavier children (P<0·001), those who were less physically active (P=0·002) and more sedentary (P<0·001), and in parents who were more concerned about their child’s weight (P<0·001) or who used greater food restriction (P<0·001).
Low levels of parental motivation to change overweight in young children highlight the urgent need to determine how best to improve motivation to initiate change.
Parents report that children’s eating behaviours are a major barrier to providing them with a healthy diet. Links between problem eating behaviours and parental feeding practices are not well established and have not previously been examined in overweight children. The aim of the present study was to assess associations between problem food behaviours, dietary intake and parental feeding practices of overweight children aged 4–8 years.
Participants were recruited for a lifestyle intervention (n 203). At baseline, children’s BMI was measured and parents completed comprehensive questionnaires about the feeding practices they used, the problem food behaviours their children exhibited and the foods their child consumed. A fussy eating scale was developed and associations were determined using correlations and regression analysis, including interactions.
Dunedin, New Zealand.
Overweight children aged 4–8 years.
Healthy eating guidance and monitoring by parents were related to the consumption of fewer unhealthy foods (B=−0·4, P=0·001 and B=−0·4, P<0·001). Conversely, a lack of parental control (child control) was related to a higher intake of unhealthy foods (B = 0·5, P<0·001). Parents of children who were fussy eaters monitored their child’s food intake less (P<0·001) and allowed the child more freedom over what he/she ate (P<0·001). These children consumed fewer fruit and vegetables than those who were not fussy eaters (P<0·001). However, fussy eaters with food-restrictive parents ate more fruit and vegetables (B=2·9, P<0·001).
These results suggest that a more structured food environment might be beneficial for the diet and food behaviours of young overweight children.
Against a backdrop of the latest ITRS predictions for CMOS junctions, we compare methods for dopant introduction and activation, methods for making contact to these regions, and methods for measurement of material and device properties. As activation without diffusion (sub-melt laser, capacitor discharge flash, or solid phase epitaxy) becomes more feasible, the burden on Xj, Rsh and abruptness falls on the implanters, and the process margin appears slim, opening the door for other methods of doping. For contact resistance, a major component of transistor parasitics, we find that either a move to a different substrate, or from a single midgap silicide to two band-edge metals/silicides can be quite beneficial. Through the use of simple test structures, we describe a means of extracting each component of the parasitic resistance, facilitating development of materials for CMOS junctions.
Photoluminescence (PL) has been investigated in hydrogenated microcrystalline silicon (μc-Si:H) samples as a function of boron doping for films prepared by remote plasma enhanced chemical vapor deposition. When the dark conductivity a is below about 10-5 S/cm, the PL spectra exhibit a shape which is close to that of the so-called band tail PL in undoped hydrogenated amorphous silicon (a-Si:H) at 77 K. When a increases, the PL intensity decreases at 77 K. For samples with a on the order of 10-3 S/cm, the PL spectra show only a narrow, low energy PL band which peaks around 0.8–0.9 eV. In these samples, the PL at higher energy is essentially not observable. This trend is similar to that which occurs in doped a-Si:H. However, for higher doping levels (σ ∼ 1 S/cm) the PL in μc-Si:H, although very weak, exhibits a broad band which contains intensity at higher energies. The absorption spectra in these samples, as measured by photothermal deflection spectroscopy (PDS), show the same relationships with the corresponding PL spectra as do the PDS spectra in doped a-Si:H.
Low energy (5–20 eV) atomic beam-surface interactions have been studied using a molecular dynamics technique. Silicon atoms are directed at an unreconstructed (111) silicon substrate either perpendicular to the surface or at grazing angles of incidence from 10–35°. The Si-Si interaction is treated using an empirical many-body silicon potential so that the effects of covalent bonding are included. At general beam orientations relative to the surface, low energy atoms are rapidly adsorbed at the surface, whereas at higher energies they either bounce off the surface or penetrate into the substrate. However, when the surface component of beam momentum is parallel to a (100) symmetry direction, Si atoms, under certain conditions, are found to channel along the surface rows, resulting in very little local excitation of the surface geometry and only gradual energy loss. The vertical momentum is carried away by substrate lattice vibrations, and the particle is guided along the surface by interaction with the atoms making up the surface ‘half-channels’. This surface channeling effect offers considerable promise for delicate control of the beam-induced annealing/growth of non-equilibrium surface geometries, and thus for high-quality growth at low temperatures.
1H NMR has been employed to study the local environments of bonded hydrogen and trapped molecular hydrogen (H2) in a series of a-Si1−xGex:H alloys. There is a monotonic decrease of bonded hydrogen with increasing x from ≈ 10 at. % at x = 0 (a-Si:H) to ≈ 1 at. % at x = 1 (a-Ge:H). The amplitude of the broad 1H NMR line, which is attributed to clustered bonded hydrogen, decreases continuously across the system. The amplitude of the narrow 1H NMR line, which is attributed to bonded hydrogen essentially randomly distributed in the films, decreases as x increases from 0 to ≈ 0.2. From x = 0.2 to x ≈ 0.6 the amplitude of the narrow 1H NMR line is essentially constant, and for x ≥ 0.6 the amplitude decreases once again. The existence of trapped H2 molecules is inferred indirectly by their influence on the temperature dependence of the spin-lattice relaxation times, T1. Through T1, measurements it is determined that the trapped H2 concentration drops precipitously between x = 0.1 and x = 0.2, but is fairly constant for 0.2 ≤ x ≤ 0.6. For a-Si:H (x = 0) the H2 concentration is ≈ 0.1 at. %, while for x ≥ 0.2 the concentration of H2 is ≤ 0.02 at. %.
Depth profiling is becoming a common method of determining composition gradients for those research facilities that have access to SIMS. The problems with this procedure are briefly discussed but well referenced for those interested in using the technique. Spectra for application of depth profiling to a tantalum pentoxide layer on tantalum, silicon implanted in silica, preferential sputtering of niobium and surface treated lithium alumina silicate glass are presented.
Application of SIMS to ceramics is a complicated but rewarding technique for characterization. The variable composition, hardness and insulating nature of these materials render spectra interpretation complex. Basic data reduction procedures from graphical data collection are presented along with spectra from SIMS applied to a glass frit, magnesium sialon, silicon and PTCR barium titanate.
High quality metallic and metallic-glass microballoons (MMB and MGMB) are of considerable interest for fusion target applications on account of the intrinsic properties of these materials such as high density, high strength and high atomic number. We report the first successfully formed submillimeter and millimeter spherical shells of tin and of a gold-lead-antimony alloy by means of the hollow-jet instability technique developed by one of us (JMK). Examination of tin specimens by means of SEM has revealed that surface quality varied from poor to excellent. Whereas this metal has been employed only as a convenient and inexpensive material, the gold alloy is important because it is hard, has high atomic number, and may be solidified into the amorphous state through the provision of a modest cooling rate. We have produced AuPbSb spherules up to 1.5 mm in diameter using LN2 or chilled methanol as a coolant, and have found that these amorphous samples possess a superb surface smoothness compatible with fusion target requirements. Hollow spheres currently made of this alloy have an average O.D. of 2000 μm.
The use of lasers to create intricate three-dimensional and buried structures  in photostructural glass has been well demonstrated at The Aerospace Corporation over the past four years. In these instances the glass used (Foturan™, made by the Schott Group) forms a silver nucleation sites on exposure to intense UV laser light via a two-photon process. Subsequent annealing causes a localized crystal growth to form a meta-silicate phase which can be etched in dilute hydrofluoric acid at rates of 20 to 50 times that of the unprocessed glass. We are now in the process of experimenting with another formulation of photosensitive glass, also pioneered by Corning Glass Works, that behaves differently during the bake process. In the second case, a photoexposure and bake process creates a silver-halide crystal and forms an adjacent void in the glass. A second photoexposure and bake allows for the migration of more silver into the void creating patterned formations of silver nano-wires . Recent experiments with this type of glass have shown that the manipulation of the size and density of the embedded nano-wires as well as the overall pattern of the clusters can be controlled using direct-write exposure to laser processing.
In this paper the impact of post deposition annealing in various ambient on electrical properties of hafnium zirconate (HfxZr1-xO2) high-k dielectrics is reported. ALD HfxZr1-xO2 films are annealed in a nitrogen and/or oxygen ambient at 500°C to 1000°C. Devices annealed at 500°C in N2 has lower equivalent oxide thickness (EOT) of 10Å without significant increase in gate leakage (Jg), threshold voltage (Vt) and only a slight decrease in transconductance (Gm) values compared to 500°C O2 annealed devices. Furthermore, the impact of annealing HfxZr1-xO2 films in a reducing ambient (NH3) is studied. Optimized NH3 anneal on HfxZr1-xO2 results in lower CET, improved PBTI, low sub-threshold swing values, comparable high-field Gm with only a minor degradation in peak Gm compared to control HfxZr1-xO2. Finally, the impact of laser annealing vs. RTP annealed HfxZr1-xO2 films are reported. Laser annealing helped further stabilize tetragonal phase of HfxZr1-xO2 without inducing void formation. Good devices with low leakage, low EOT and high mobility are obtained for laser annealed HfxZr1-xO2.