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Many women experience both vasomotor menopausal symptoms (VMS) and depressed mood at midlife, but little is known regarding the prospective bi-directional relationships between VMS and depressed mood and the role of sleep difficulties in both directions.
A pooled analysis was conducted using data from 21 312 women (median: 50 years, interquartile range 49−51) in eight studies from the InterLACE consortium. The degree of VMS, sleep difficulties, and depressed mood was self-reported and categorised as never, rarely, sometimes, and often (if reporting frequency) or never, mild, moderate, and severe (if reporting severity). Multivariable logistic regression models were used to examine the bi-directional associations adjusted for within-study correlation.
At baseline, the prevalence of VMS (40%, range 13–62%) and depressed mood (26%, 8–41%) varied substantially across studies, and a strong dose-dependent association between VMS and likelihood of depressed mood was found. Over 3 years of follow-up, women with often/severe VMS at baseline were more likely to have subsequent depressed mood compared with those without VMS (odds ratios (OR) 1.56, 1.27–1.92). Women with often/severe depressed mood at baseline were also more likely to have subsequent VMS than those without depressed mood (OR 1.89, 1.47–2.44). With further adjustment for the degree of sleep difficulties at baseline, the OR of having a subsequent depressed mood associated with often/severe VMS was attenuated and no longer significant (OR 1.13, 0.90–1.40). Conversely, often/severe depressed mood remained significantly associated with subsequent VMS (OR 1.80, 1.38–2.34).
Difficulty in sleeping largely explained the relationship between VMS and subsequent depressed mood, but it had little impact on the relationship between depressed mood and subsequent VMS.
Rock dust appears to have been redistributed over the Moon by effects other than impact explosions. A core sample on Apollo 12 showed sharp and distinctive layers and was clearly unmixed. Surface transportation processes that deposit the dust very gently must have been at work. Orbiter pictures confirm that such surface creep has taken place on a very large scale.
The seismic evidence makes clear that there is no continuous sheet of bedrock at a shallow depth in the vicinity of the Apollo 12 site. A deep deposit of powder would match the seismic properties observed. Mascons require for their explanation a surface transportation process that tends to fill in the large impact basins after their formation.
Surface transportation of lunar dust has been demonstrated in the laboratory to occur most readily as a result of electrostatic forces produced by electron bombardment in the energy range of a few hundred volts. Such bombardment happens on the Moon predominantly when it is in the magnetic tail of the Earth, and this may be the reason why mare ground is so remarkably dominant on the hemispere facing the Earth.
The shapes of coronal features are discussed, on the basis that they are indicative of the configurations of the magnetic fields. Some considerations about the strength of the fields are advanced, and the forces that must be responsible for streamers and for the quiet corona are discussed. The magnetic fields would seem to dominate over all inertial hydrodynamic forces, leaving only such magnetic configurations as can be set up by variations of the gas pressure.
The basic idea that pulsars may be the origin of cosmic rays arises when one realizes that they meet some of the criteria, perhaps not all as yet, for an origin theory of cosmic rays. Those criteria are: (1) there must be some possible mechanism that one can recognize for the acceleration of particles; and the pulsars have given us a very clear hint that particles are accelerated to at least the medium range of energies of cosmic rays - 1013 eV. (2) The objects that are thought responsible for cosmic rays must have enough total energy available to them to produce the entire cosmic ray beam in the Galaxy. I will come back to that, but it is clear that the total number of pulsars that one might expect in the Galaxy can indeed produce an adequate supply and even a good margin above that, if one makes the estimate on the basis of one plausible set of assumptions. (3) One would like of course that the mechanism proposed should generate the right spectrum; but there we as yet know too little. We do not understand what the energy spectrum of particles accelerated in pulsars should be, and we cannot as yet make any conclusive statement as to whether this spectrum can or cannot match the observed cosmic ray spectrum in the Galaxy. There is no reason for thinking otherwise, but there is no positive evidence in favor at the moment.
Then we have (4) the problem that the process selected must generate the correct composition. There we have the problem that we have just discussed, which is certainly a difficult one; I don’t know that it is completely clear what type of particles you must expect to come from pulsars; how much of the material accelerated in the vicinity of the pulsar is material that is being cycled into it at the time and going out again; and how much is material which is preferentially sucked out of the surface, perhaps by reason of a high charge-to-mass ratio.
Satellites are a common feature in the solar system, and all planets on which satellite orbits would be stable possess them. (For Mercury the solar perturbation is too large, and the retrograde spin of Venus would cause satellites to spiral in to the planet through tidal friction.) An explanation of the formation of satellites must hence be one which makes the phenomenon exceedingly probable at some stage in the solar system formation processes, and very improbable processes like a capture cannot be the answer in most cases.
Small particulate matter must have been very abundant in the early solar nebula. Such particulate matter must have existed both from the first condensation of the low vapor pressure components of the gas in the first round, and it must also have been composed of material scattered from impacts after some major bodies had begun to form, frequently finding themselves no doubt on collision orbits.
Attempts to explain both the expansion of the universe and the condensation of galaxies must be very largely contradictory so long as gravitation is the only force field under consideration. For if the expansive kinetic energy of matter is adequate to give universal expansion against the gravitational field it is adequate to prevent local condensation under gravity, and vice versa. This is why, essentially, the formation of galaxies is passed over with little comment in most systems of cosmology. Yet the galaxies, and the clusters in which they are often found, are such an important characteristic property of the universe that it is unsatisfactory to dismiss their origin in the vague term “fluctuation phenomenon.”
We investigated a possible outbreak of H. pylori in a rural Northern Plains community. In a cross-sectional survey, we randomly sampled 244 households from a geocoded emergency medical system database. We used a complex survey design and global positioning system units to locate houses and randomly selected one eligible household member to administer a questionnaire and a 13C-urea breath test for active H. pylori infection (n = 166). In weighted analyses, active H. pylori infection was detected in 55·0% of the sample. Factors associated with infection on multivariate analysis included using a public drinking-water supply [odds ratio (OR) 12·2, 95% confidence interval (CI) 2·9–50·7] and current cigarette smoking (OR 4·1, 95% CI 1·7–9·6). People who lived in houses with more rooms, a possible indicator of decreased crowding in the home, were less likely to have active H. pylori infections (OR 0·7, 95% CI 0·5–0·9 for each additional room).
We propose a generalized ellipsometric technique using a rotating sample. The ellipsometer consists of a polarizer, a rotatable sample holder, an analyzer, and a detector. Fourier coefficients are measured and used to extract the system’s dielectric tensors and film thicknesses. The main advantage of the technique is that all parts of the ellipsometer are fixed except the sample, whose azimuth angle can be modulated. We show calculated responses to isotropic and anisotropic materials as well as superlattices. Potential applications for characterizations of anisotropic nanostructures are discussed.
We have carried out finite-inductance calculations of the critical current vs, flux(Ic-φ) and voltage vs, flux (V-φ) characteristics of superconducting interferometers with many Josephson junctions (JJ's) in parallel. At least two features of our calculations suggest that interferometers with many junctions, which we call Superconducting QUantum Interference Gratings, or SQUIG's, might be advantageous for the detection of magnetic flux. First, the voltage noise can potentially be reduced significantly as compared to a dc SQUID with the same overall voltage-to-flux transfer coefficient - a feature which might reduce 1/f noise and enhance the magnetic flux sensitivity of both low and high Tc superconducting (HTS) devices. In addition, nonuniformity of the junction critical currents appears to have little adverse effect on the predicted diffraction-grating like enhancement and narrowing of the peaks in the Ic-φcharacteristic, suggesting that flux uniformity, rather that critical current uniformity, is of primary importance.
We report studies of the interface formed when InSb is deposited onto a CdTe substrate in a molecular beam epitaxy chamber and elucidate conditions under which epitaxial growth is possible. We find that a necessary condition for epitaxy at a substrate temperature Ts is that the growth rate exceed a minimum value Ωmin(Ts). Reflection high energy electron diffraction patterns taken in situ and transmission electron micrographs taken ex situ show that interfaces formed when Ω > Ωmin have a short period roughness which is independent of the Sb/In flux ratio and which diminishes with increasing Ω. Raman spectra show no evidence of interfacial compounds. An analysis of Auger spectra of thin layers of InSb grown on CdTe indicates the existence of Te at the surface of the InSb but not in the layer itself. The Te concentration is found to decrease with InSb layer thickness. We propose a model based on a competition between the reaction of free In and Sb with the CdTe surface and the nucleation and growth of InSb. We use this model to account for the existence of Omin, interface roughness, and the presence of Te at the surface of the InSb epilayer.
We have investigated the molecular beam epitaxial growth of homoepitaxial InAs and GaSb and InAs/GaSb heterostructures on both the (111)A and (111)B orientations. Our studies have found that high quality GaSb epilayers can be grown on both the (111)A and (111l)B orientations over a wide range of growth temperatures and flux ratios. Reflection high energy electron diffr-action phase diagrams for GaSb [111[ are presented. InAs/GaSb heterostructures, simultaneously grown on (11l)A and (111)B orientations, have been investigated by secondary ion mass spectroscopy depth profiles and double crystal x-ray diffraction. Unintentional incorporation of the ‘second’ group-V element is found to be approximately three times greater in the (111)A orientation than in the (111)B for both species.
A substantial research effort has been devoted to the growth of metals on semiconductors , motivated in part by the necessity of electrical contacts and interconnects in semiconducting devices and by the possibility of new physical phenomena and devices derived from the combination of electronic properties of the two materials. Semimetals provide an alternative for applications involving electrical contact, for which their unique transport, optical, and nonlinear properties make them attractive in hybrid devices.
Strain can play a critical role in determining the band structure and optical properties of semiconducting superlattices. Mailhiot and Smith  have predicted that strain, induced by mismatch, in InxGal-xSb/InAs makes the superlattice a candidate for infrared detectors. We present a preliminary analysis of the structure, in particular the strain in the layers, of an InxGal-xSb/InAs superlattice, which shows infrared absorption. Our ultimate objective is to relate the structural properties to the optical absorption and an extended (kinematical) diffraction treatment is presented for accomplishing this.
Small punch (SP) tests on single grained titanium aluminide (Ti-48 at.%Al) specimens with 12° and 80° lamellar orientations with respect to the tensile stress axis were conducted at 1123 K in air. Brittle cracks readily extended through the thickness in the 80° lamellar structure. In a SP specimen with the 12° lamellar structure load-interrupted at the strain of 0.43%, surface cracks with the depth of 15–25 μm were formed along lamellar boundaries. Local oxidation behavior on partly sputtered surfaces in the load-interrupted 12° lamellar specimen was examined using scanning Auger microprobe (SAM). Oxygen enriched regions were observed near cracks and some lamellar layers. The mechanisms of high temperature oxygen-induced cracking are discussed in terms of the local oxidation near cracks and lamellar boundaries.
This paper describes the effect of post-irradiation annealing (PIA: 573-873K for 10 h) on the microhardness and intergranular P segregation in P doped and Cu-P doped iron alloys containing residual S. Hardening and softening occurred during PIA at lower and higher temperatures, respectively. PIA-induced hardening was more profoundly observed in the Cu-P doped alloy. Intergranular P enrichment was achieved by lower temperature PIA and P desegregation associated with S segregation dominated at higher PIA temperatures in both the alloys. Changes in the microhardness and intergranular P segregation induced by the PIA were found to be correlated with each other although the Cu-P doped alloy showed more scatter. The dynamic interaction between solute and defects in the grain interior and near grain boundaries during the PIA is discussed in order to explain the experimental observation.
This paper describes examination of in-service coating degradation in land based gasturbine blades by means of a small punch testing (SP) method and scanning Auger microprobe(SAM). SP tests on coated specimens with unpolished surfaces indicated large variations ofthe mechanical properties because of the surface roughness and curvature in gas turbine blades, SP tests on polished specimens better characterized the mechanical degradation of bladecoatings. The coated specimens greatly softened and the room temperature ductility of thecoatings and substrates tended to decrease with increasing operation time. The ductile-brittletransition temperature of the coatings shifted to higher temperatures during the bladeoperation. From SAM analyses on fracture surfaces of unused and used blades, it has beenshown that oxidation and sulfidation near the coating surface, which control the fractureproperties, result from high temperature environmental attack.
X-ray scattering and transmission electron microscopy (TEM) have been used to study short-range order in Al1−xlnxAs thin films grown by molecular beam epitaxy. Two samples grown on (001) InP at temperatures of 370°C and 400°C are characterized. The first exhibits simultaneous triple-period-A and CuPt-A short-range order with a rather short correlation range of about 2.4 nm normal to the (111) planes. Within these (individual) planes the concentration, however, is uniform over a considerably greater distance – about 6 to 9 nm – leading to a highly anisotropic scattering. This observation of triple-period short-range ordering in a sample that exhibits 2×1 surface reconstruction during growth is unexpected. We also report on the first observation of the coexistence of triple-period-A and CuPt-B short-range order. The diffuse scattering exhibits significant intensity anomalies that we attribute to atomic displacements associated with the short-range order. The second sample exhibits CuPt-B short-range ordering with scattering that is significantly streaked, suggestive of lamellar-shaped ordered domains. This sample also exhibits intensity anomalies that must be associated with atomic displacements. The first sample contains a high density of twin lamellae, while both samples contain high densities of stacking faults leading to additional narrow streaking along symmetry-allowed 〈111〉 directions. These growth faults most likely arise from the relatively low growth temperatures.
We investigate the optical properties of a new class of wide-bandgap semiconductor based biomaterial system. We have synthesized a guanosine derivative with a strong dipole moment, which self-assemble in ∼ 50 –100 nm confined pits to form a ribbon like semiconductor structure (SAGC). SAGC were successfully self-assembled on GaN/AlN QD matrix and the luminescence from GaN QDs can be resonantly transferred to the SAGC molecules resulting in a significant enhancement in emission from the guanine molecules. We also propose the design of ultraviolet-visible photonic bandgap structures based on hybrid SAGC-GaN photonic crystal.