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Indigenous women and children experience some of the most profound health disparities globally. These disparities are grounded in historical and contemporary trauma secondary to colonial atrocities perpetuated by settler society. The health disparities that exist for chronic diseases may have their origins in early-life exposures that Indigenous women and children face. Mechanistically, there is evidence that these adverse exposures epigenetically modify genes associated with cardiometabolic disease risk. Interventions designed to support a resilient pregnancy and first 1000 days of life should abrogate disparities in early-life socioeconomic status. Breastfeeding, prenatal care and early child education are key targets for governments and health care providers to start addressing current health disparities in cardiometabolic diseases among Indigenous youth. Programmes grounded in cultural safety and co-developed with communities have successfully reduced health disparities. More works of this kind are needed to reduce inequities in cardiometabolic diseases among Indigenous women and children worldwide.
Trans-10, cis-12 CLA is produced as an intermediary during the biohydrogenation of linoleic acid (C18:2 n-6) in the rumen and has been shown to be a potent inhibitor of milk fat synthesis in ruminants. The production of trans-10, cis-12 CLA in the rumen is affected by dietary concentrate: forage ratio (Kucuk et al., 2001), rumen pH and the amount and source of linoleic acid in the diet. However, the interaction between oil source, carbohydrate source and pH on the production of trans-10, cis-12 CLA is unclear (Beam et al., 2000). The objectives of the current study were to determine the effects of oil source, carbohydrate source and pH on the biohydrogenation of linoleic acid and production of trans-10, cis-12 CLA in vitro.
The Southern Hemisphere VLBI Experiment (SHEVE) program is aimed at producing high-resolution images of southern radio sources. The radio telescopes of the present SHEVE array are described below and some recent results presented.
Recent results on the diffuse scattering from single crystals of Fe1−xO at high temperatures reveal that the defect structure is in striking agreement with embedded cluster calculations by Ellis et al. The dominant defect is an imperfect 7:2 cluster. Mixtures of this and a larger complex (13:4) can explain the electrical properties. XANES studies of this oxide are in agreement with Ellis' theoretical work. However, in both FOx and MnxO it is not possible to use the shift of the cation K absorption edge to characterize valence. In fact in the latter case the shift passes through a minimum, perhaps indicating the onset of clustering.
In Al-Cu alloys containing Guinier-Preston zones, the scattering contributions due to short-range order and atomic displacements vary differently when the scattering contrast between Al and Cu is changed. The diffuse neutron scattering of Al-Cu single crystals containing 63Cu or 65Cu is compared and evaluated to test the current methods of separating the two scattering contributions. - The nature of a sugggtted ordered state in α-brass is also studied by neutron scattering, using Cu to enhance the scattering contrast in a Cu-30 at.% Zn alloy. A broad diffuse peak is found in powdered, appropriately aged samples, confirming that the first Warren-Cowley short-range order parameter is negative.
Large-angle diffuse scattering has been investigated for the purpose of studying coherent precipitates in a crystal lattice. Detailed calculations have been made of the scattering near Bragg reflections from cobalt precipitates in a copper host lattice. These calculations have been compared to x-ray diffuse scattering measurements made on aged (570°C for 17 hr.) Cu-0.95%Co crystals with x-rays of three different wavelengths at the NSLS. The results indicate that the size distribution, the concentration, and the internal strain of the precipitates can be determined from such diffuse scattering measurements.
The dislocation loop shape in high stress deformed GaAs can be used to obtain information on the relative velocity of individual dislocation segments. It is shown that 30/90 β-dislocations and 90/30 β-dislocations have different velocities. A variety of loop shapes observed can be modelled by focussing on differences in mobility of individual kinks. It is shown that the observation of faulted dipoles is only possible in high stress p-type GaAs in which the screw dislocation segments have appreciable velocity at the low temperatures used during the deformation.
Resistance tube closure welds, referred to as pinch welds, are used to reliably seal small stainless steel tubing . The quality of the bond is dependent upon, among other factors, the cleanliness of the tube bore. Post weld inspections are therefore desired as process control procedures. In previous studies, ultrasonics was shown to have considerable promise in this application. Thomas et al.  demonstrated that pattern recognition algorithms could be applied to the ultrasonic signals transmitted through the tubes to produce a correct classification of good and bad welds in several different sets of samples. The algorithms were somewhat dependent on the material from which the samples were fabricated, but all showed a good deal of commonality. In a parallel study, Rehbein et al.  examined, from a more mechanistic point of view, sets of tubes fabricated at the same time. They observed that gross disbonds could be easily detected from changes in signals either reflected from or transmitted through the bond line. When such disbonds were not present, they observed that signals doubly transmitted through the interface (i.e., the back surface echo) showed a trend to lower values as the bond quality decreased. This paper describes the sequel to that study, having the objective of developing a quantitative understanding of the interaction of the ultrasound with the pinch welds.
A detailed comparison of small-angle scattering (SANS) and large angle x-ray diffraction methods of characterization of precipitates was undertaken. Cobalt-rich precipitates on the order of 50 Å developed after a 17 hour anneal at 570°C were studied in a single crystal sample with SANS and with diffuse x-ray scattering near the (400)Bragg peak. Each scattering data set was analyzed independently in terms of a distribution of precipitate sizes; a detailed comparison is made of the size distribution obtained. A small interparticle interference effect is seen.
Lithographic techniques have been used to prepare transmission electron microscopy samples of MoS2, allowing examination of the edge surface with single-layer resolution. We observe that these surfaces are easily disordered by chemical treatments common in the catalysis industry. In some cases treatment in H2/H2S leads to an exfoliation of the layered structure, a process which can be observed as it occurs in the microscope.
Evidence for a tetranuclear aluminum oxoalkoxide cluster Al4(μ4-0) (μ2OBμi)5(OBui)6 is presented, drawing on data from X-ray, NMR, MS and other spectroscopie and experimental investigations. In principle, these compounds are derived from the well-authenticated aluminum alkoxide tetramers by hydrolytic loss of only one alkoxy group. They contain a single central oxo ligand and only 5-coordinate aluminum atoms. They are the simplest discrete oxoalkoxide structures so far reported for aluminum and may be helpful in understanding the hydrolysis and condensation steps leading to hydrated aluminum oxide sols and gels.
This article describes the application of in situ, high-resolution electron microscopy to the study of crystal nucleation and growth in amorphous silicon. It is shown that dynamic events at elevated temperatures (e.g. 600-750°C) can be recorded at the atomic level by such an approach. It is anticipated that fundamental information, important for the technological development of polysilicon thin films, can be generated by work of this type.
We report structural properties of PtFe and PtCo intermetallic compounds with perpendicular magnetic anisotropy and a preferred c-axis orientation perpendicular to the film plane, formed from initially epitaxial multilayers. These materials represent particular cases of a more general class of anisotropic magnetic compounds with the CuAu(1) natural superlattice structure. They possess high magneto-optic Kerr rotations and magnetizations, suggesting them as likely candidates for magneto-optic and perpendicular magnetic recording media.
High resolution electron microscopy (HREM) has been used to study the atomic arrangement of defects formed during high-dose oxygen implantation of silicon-on-insulator material. The effect of implantation parameters of wafer temperature, dose, and current density were investigated. Wafer temperature had the largest effect on the type and character of the defects. Above the buried oxide layer in the top silicon layer, HREM revealed that microtwins and stacking faults were created during implantation from 350–450°C. From 450–550°C, stacking faults were longer and microtwinning was reduced. From 550–700°C, a new type of defect was observed which had lengths of 40 to 140 nm and consisted of several discontinuous stacking faults which were randomly spaced and separated by two to eight atomic layers. We have referred to them as “multiply faulted defects” (MFDs). Beneath the buried oxide layer in the substrate region, the defects observed included stacking faults and ( 113 ) defects. The results indicated that some parts of the ( 1131 defects can assume a cubic diamond structure created through a twin operation across (115) planes. Details of the structure and formation mechanisms of MFDs and other defects will be discussed.
We have studied the micro-structure of shock synthesized Tl2Ba2CuO6, shockprocessed YBa2Cu3O7 and 10% Ag-YBa2Cu3O7. The structural interpretation of the defects observed in these materials is discussed and compared with computer simulated images. Two planar defects with a stacking sequence of Cu-Ba-Tl-Ba-Cu and Cu-Ba-Tl-Tl-Ba-Cu-Tl-Cu-Ba-Tl-Tl-Ba-Cu in the Tl based oxide and a new defect sequence of Cu-Ba-Cu-Y-Y-Cu-Ba-Cu in the Y based oxides are reported here. An attempt is made to relate the change in superconducting properties observed to the defect structure present.