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Although financing represents a critical component of health system strengthening and also a defining concern of efforts to move towards universal health coverage, many countries lack the tools and capacity to plan effectively for service scale-up. As part of a multi-country collaborative study (the Emerald project), we set out to develop, test and apply a fully integrated health systems resource planning and health impact tool for mental, neurological and substance use (MNS) disorders.
A new module of the existing UN strategic planning OneHealth Tool was developed, which identifies health system resources required to scale-up a range of specified interventions for MNS disorders and also projects expected health gains at the population level. We conducted local capacity-building in its use, as well as stakeholder consultations, then tested and calibrated all model parameters, and applied the tool to three priority mental and neurological disorders (psychosis, depression and epilepsy) in six low- and middle-income countries.
Resource needs for scaling-up mental health services to reach desired coverage goals are substantial compared with the current allocation of resources in the six represented countries but are not large in absolute terms. In four of the Emerald study countries (Ethiopia, India, Nepal and Uganda), the cost of delivering key interventions for psychosis, depression and epilepsy at existing treatment coverage is estimated at US$ 0.06–0.33 per capita of total population per year (in Nigeria and South Africa it is US$ 1.36–1.92). By comparison, the projected cost per capita at target levels of coverage approaches US$ 5 per capita in Nigeria and South Africa, and ranges from US$ 0.14–1.27 in the other four countries. Implementation of such a package of care at target levels of coverage is expected to yield between 291 and 947 healthy life years per one million populations, which represents a substantial health gain for the currently neglected and underserved sub-populations suffering from psychosis, depression and epilepsy.
This newly developed and validated module of OneHealth tool can be used, especially within the context of integrated health planning at the national level, to generate contextualised estimates of the resource needs, costs and health impacts of scaled-up mental health service delivery.
The turkey (Meleagris gallopavo) was independently domesticated in Mesoamerica and the Southwest, the latter as the only case of Native American animal domestication north of Mexico. In the upland (non-desert) portion of the American Southwest, distinctive closely related mtDNA lineages belonging to haplogroup H1 (thought to indicate domestication) occur from ca. 1 A.D. (Basketmaker II period) through early historic times. At many sites, low frequencies of lineages belonging to haplogroup H2 also occur, apparently derived from the local Merriam’s subspecies. We report genetic, stable isotope, and coprolite data from turkey remains recovered at three early sites in SE Utah and SW Colorado dating to the Basketmaker II, III, and early Pueblo II periods. Evidence from these and other early sites indicates that both the H1 and H2 turkeys had a predominantly maize-based diet similar to that of humans; prior to late Pueblo II times, the birds were kept primarily to provide feathers for blankets and ritual uses; and ritualized burials indicate turkeys’ symbolic value. We argue that viewing individuals from the H1 and H2 haplogroups as “domestic” versus “wild” is an oversimplification.
§ 1. Let L2(0, ∞) denote the Hilbert space of Lebesgue measurable, integrable-square functions on the half-line [0, ∞).
Integral operators of the form
acting on the space L2 (0, ∞) occur in the theory of ordinary differential equations; see for example the book by E. C. Titchmarsh [4; § 2.6]. It is important to establish when operators of this kind are bounded; see the book by A. E. Taylor [3; § 4.1 and §§4.11, 4.12 and § 4.13].
We investigate the formation of inAs-rich layers at the interface between InP and arsenicbased Ill-V alloys grown by chemical beam epitaxy (CBE). In-situ spectroscopic ellipsometry, low temperature photoluminescence, secondary ion mass spectrometry and transmission electron microscopy were used to characterize the formation of these layers. We present evidence for interfacial layer roughness that depends strongly on growth temperature and on the presence of surface steps, and show that modifications of the interface chemistry and of the gas-switching sequence can reduce interfacial layer thicknesses.
Partial dislocations and their associated stacking faults are identified as the primary defects responsible for the initial relaxation of tensile-strained layers of fcc structure. The critical thickness for the formation of 90° partial dislocations at the strained interface is almost a factor of two smaller than that predicted for the formation of 60° perfect dislocation. Microstructures revealed by transmission electron microscopy from strained layers of various lattice mismatches and thicknesses agree with the prediction of the standard free-energy minimization model.
The growth of CuCl/CaF2 heterostructures has been studied with an atomic force microscope (AFM). We have grown by molecular beam epitaxy (MBE) CuCl thin films at various substrate temperatures and thicknesses on CaF2(111) substrates. AFM studies reveal that islanding is the dominant growth mechanism. We calculated the height-height correlation function, 〈lh(qt)|2〉, for each of our films and compared them to the predictions made by the Shadowing Growth Theory, a preexisting growth model that enabled us to extract the important kinetic parameter of surface diffusion length for the growth condition of each of the four films.
The formation of a buried IrSi3 layer in (111) oriented Si by ion implantation and annealing has been studied at an implantation energy of 2 MeV for substrate temperatures of 450–550°C. Rutherford backscattering (RBS), ion channeling and cross-sectional transmission electron microscopy showed that a buried epitaxial IrSi3 layer is produced at 550°C by implanting ≥ 3.4 × 1017 Ir/cm2 and subsequently annealing for 1 h at 1000°C plus 5 h at 1100°C. At a dose of 3.4 × 1017 Ir/cm2, the thickness of the layer varied between 120 and 190 nm and many large IrSi3 precipitates were present above and below the film. Increasing the dose to 4.4 × 1017 Ir/cm2 improved the layer uniformity at the expense of increased lattice damage in the overlying Si. RBS analysis of layer formation as a function of substrate temperature revealed the competition between the mechanisms for optimizing surface crystallinity vs. IrSi3 layer formation. Little apparent substrate temperature dependence was evident in the as-implanted state but after annealing the crystallinity of the top Si layer was observed to deteriorate with increasing substrate temperature while the precipitate coarsening and coalescence improved.
The density of misfit dislocations in GexSi1−x films has been measured as a function of deposition temperature and r-f plasma power in Remote Plasma-enhanced Chemical Vapor Deposition (RPCVD). The misfit dislocation density decreases as the deposition temperature is lowered from 450°C to 410°C. As the plasma power is increased from 6.6 to 16W, the dislocation density peaks at lOW and then decreases with increasing power.
For the first time, Si1 xGex layers on amorphous SiO 2 were produced by modification of the Si surface layer of a SIMOX wafer. We used two alternative methods. An additional Si1.. Gey layer was deposited epitaxially on a SIMOX wafer followed by rapid thermal annealing. Diffusional intermixing of the layers produced a homogeneous Si1 xGex layer on SiO 2. In a second attempt, Ge was implanted into the Si surface layer and thermally treated. In both cases epitaxial Si1 xGex layers on SiO2 with minimum yield values around 9% were obtained. Rutherford backscattering and cross sectional transmission electron microscopy were used to characterize the new structures.
The interdiffusion in MBE-grown Si/Si1−xGex superlattices was measured by Rutherford backscattering spectrometry. The superlattices consisted of 5 periods of 100 !A Si and 100 !A Si1−xGex layers with Ge concentrations, x, between 0.20 and 0.70. Both, asymmetrically strained superlattices, grown on Si(100), as well as symmetrically strained superlattices, grown on relaxed Si1−y.Gey buffer layers were investigated. Rapid thermal annealing in the temperature range between 900°C and 1125°C leads to significant interdiffusion between the individual layers, indicated by a decrease of the amplitudes of the backscattering spectra. Interdiffusion coefficients were deduced using a Fourier algorithm. The interdiffusion coefficients follow an Arrhenius law for a given Ge concentration. The interdiffusivity increases significantly with increasing Ge concentration.
It is shown how the use of a high angle annular detector in a STEM provides images which show strong compositional sensitivity and almost perfect incoherent characteristics. No contrast reversals occur with defocus or sample thickness and the contribution of an atomic string is insensitive to the distribution and strength of neighboring strings. The image is best described in real space as a simple convolution of the incident probe intensity profile with an object function sharply peaked at the atomic strings having a strength dependent on composition. How the incoherent characteristics arise is described using a Bloch wave approach and examples are shown of interfaces in semiconductor and superconductor materials.
The macroscopic properties of many materials are controlled by the structure and chemistry at grain boundaries. A basic understanding of the structure-property relationship requires a technique which probes both composition and chemical bonding on an atomic scale. High-resolution Z-contrast imaging in the scanning transmission electron microscope (STEM) forms an incoherent image in which changes in atomic structure and composition across an interface can be interpreted directly without the need for preconceived atomic structure models (1). Since the Z-contrast image is formed by electrons scattered through high angles, parallel detection electron energy loss spectroscopy (PEELS) can be used simultaneously to provide complementary chemical information on an atomic scale (2). The fine structure in the PEEL spectra can be used to investigate the local electronic structure and the nature of the bonding across the interface (3). In this paper we use the complimentary techniques of high resolution Zcontrast imaging and PEELS to investigate the atomic structure and chemistry of a 25° symmetric tilt boundary in a bicrystal of the electroceramic SrTiO3.
The combination of atomic-resolution Z-contrast microscopy, electron energy loss spectroscopy and first-principles theory has proved to be a powerful means for structure property correlations at interfaces and nanostructures. The scanning transmission electron microscope (STEM) now routinely provides atomic-sized electron beams, allowing simultaneous Z-contrast imaging and EELS as shown in Fig. 1. The feasiblity of correcting the inherently large spherical aberration of microscope objective lenses promises to at least double the achievable resolution. The potential benefits for the STEM, however, may turn out to be much greater than those for the conventional TEM because it is very much less sensitive to chromatic instabilities. The 100 kV VG Microscopes HB501UX at Oak Ridge National Laboratory (ORNL) is now fitted with an aberration corrector constructed by Nion Co., which improved its resolution from 2.2 Å (full-width-half-maximum probe intensity) to around 1.3 Å. It is now very comparable in performance to the uncorrected 300 kV HB603U STEM at ORNL which, before correction, also had a directly interpretable resolution of 1.3 Å, although information transfer had been demonstrated down to 0.78 Å8. Initial results after installing an aberration corrector on the 300 kV STEM indicate a resolution of 0.84 Å. The theoretically achievable probe size in the absence of instabilities is predicted to be 0.5 Å.
The interface passivation process based on post-oxidation, high temperature anneals in nitric oxide (NO) is well established for SiO2 on (0001) 4H-SiC. The NO process results in an order of magnitude or more reduction in the interface state density near the 4H conduction band edge. However, trap densities are still high compared to those measured for Si / SiO2 passivated with post-oxidation anneals in hydrogen. Herein, we report the results of studies for 4H-SiC / SiO2 undertaken to determine the effects of additional passivation anneals in hydrogen when these anneals are carried out following a standard NO anneal. After NO passivation and Pt deposition to form gate contacts, post-metallization anneals in hydrogen further reduced the trap density from approximately 1.5 × 1012 cm−2eV−1 to about 6 × 1011 cm−2eV−1 at a trap energy of 0.1 eV below the band edge for dry thermal oxides on both (0001) and (11–20) 4H-SiC.
The aberration-corrected STEM allows nanostructures to be investigated with greater resolution and sensitivity than ever before. Single atom sensitivity is achieved both in imaging and also for spectroscopy, for atoms on surfaces or within the bulk. Nanocrystal size, shape, surface termination, 3D structure and the presence of any defects can be seen with unprecedented ease. The improved sensitivity provides improved input for theory, allowing new insights into nanostructure properties and the origin of their unique functionality. Furthermore, the larger aperture available with aberration-corrected STEM improves the depth resolution dramatically. Nanometer depth resolution can be achieved by simply taking a focal series of images, which may then be reconstructed into a 3D rendering of the material in the same manner as with confocal optical microscopy but maintaining sensitivity to individual atoms.
Nuts are known for their hypocholesterolaemic properties; however, to achieve optimal health benefits, nuts must be consumed regularly and in sufficient quantity. It is therefore important to assess the acceptability of regular consumption of nuts. The present study examined the long-term effects of hazelnut consumption in three different forms on ‘desire to consume’ and ‘overall liking’. A total of forty-eight participants took part in this randomised cross-over study with three dietary phases of 4 weeks: 30 g/d of whole, sliced and ground hazelnuts. ‘Overall liking’ was measured in a three-stage design: a pre- and post-exposure tasting session and daily evaluation over the exposure period. ‘Desire to consume’ hazelnuts was measured during the exposure period only. Ratings were measured on a 150 mm visual analogue scale. Mean ratings of ‘desire to consume’ were 92 (sd 35) mm for ground, 108 (sd 33) mm for sliced and 116 (sd 30) mm for whole hazelnuts. For ‘overall liking’, the mean ratings were 101 (sd 29) mm for ground, 110 (sd 32) mm for sliced and 118 (sd 30) mm for whole hazelnuts. Ground hazelnuts had significantly lower ratings than both sliced (P ≤ 0·034) and whole hazelnuts (P < 0·001), with no difference in ratings between sliced and whole hazelnuts (P ≥ 0·125). For each form of nut, ratings of ‘overall liking’ and ‘desire to consume’ were stable over the exposure period, indicating that not only did the participants like the nuts, but also they wished to continue eating them. Therefore, the guideline to consume nuts on a regular basis appears to be a sustainable behaviour to reduce CVD.