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Notes: The evolution of surface morphologies of films prepared by ion-based deposition techniques has been investigated by atomic force microscopy. Two deposition processes, filtered arc deposition (FAD) and ion-beam-assisted deposition, where low-energy (〈100 eV) ion irradiation and high-energy (several tens of keV) ion-beam bombardment concurrent with film growth were involved, respectively, have been employed to prepare TiN and Al films. Comparative studies on the effect of energetic ions on the development of topography have been performed between the low-ion-energy regime and high-ion-energy regime. In addition, the relationship between topography and mechanical properties of thin films has been revealed, by involving thin films prepared by thermal evaporation deposition (TED), where almost all depositing particles are neutral. In the images of the TED TiN and Al films, a large number of porous and deep boundaries between columnar grains was observed, suggesting a very rough and loose surface. In contrast, the FAD films exhibited much denser surface morphologies, although still columnar. The root-mean-square roughness of the FAD films was less than 1 A(ring). Hardness test and optical parameter measurement indicated that the FAD films were much harder and, in the case of optical films, much more transparent than the TED films, which was considered to arise from the denser surface morphologies rather than crystallization of the films. The high density and super smoothness of the FAD films, and the resultant mechanical and optical properties superior to those of the TED films, were attributed to the enhancement of surface migration of the deposited adatoms in the FAD process, which could provide intensive low-energy ion irradiation during film growth. As for topography modification by high-energy ion-beam bombardment concurrent with film growth, in addition to the increase of surface diffusion due to elastic collision and thermal spikes, physical sputtering must be considered while explaining the development of the film topography. Both surface migration enhancement and sputtering played important roles in the case of high-energy heavy-ion-beam bombardment, under which condition surface morphology characterized by dense columns with larger dimension and deep clean boundaries was formed. However, under high-energy light-ion-beam bombardment, the sputtering was dominant, and the variation of sputtering coefficient with position on the surface of growing film led to the formation of cones. © 1996 American Institute of Physics.

Notes: Seebeck, electrical, and thermal conductivity data are reported on CoSb3, and doped and undoped alloys of Co1−xIrxSb3−yAsy from 20 to 700 K. n-type semiconductors were obtained by doping with Ni, Te, or Pd, and the hole concentration in p-type samples was increased by substitution of Fe, Ru, Os, and Ge. An estimated maximum value for ZT of 0.6 (Z is the figure of merit) was found for a Te-doped (n-type) alloy at 700 K. For p-type alloys, the maximum value of ZT was found to be 0.3 at 550 K. Electrical and thermal transport data also are reported for CoAs3, RhSb3, and IrSb3. Most of the samples investigated were polycrystalline, but a few measurements on CoSb3 single crystals also are discussed. © 1995 American Institute of Physics.

Notes: . This paper uses new estimates of metropolitan factor demand and output supply functions to study how federal, state, and local fiscal policies affect metropolitan economies. We illustrate our work with findings for ten metropolitan areas in five states for changes in state corporate income taxes, local property taxes, the federal corporate income tax, an investment tax credit, interest rates, public capital stocks, output prices, and tax and regulatory policies affecting gross wages. It is clear from these simulations that a policy that is nominally the same everywhere will have repercussions that vary widely across regions and cities.

Notes: . In this study we use a translog profit function and iterate seemingly unrelated regressions to estimate a system of factor demand and output supply functions for metropolitan economies. Our sample includes all metropolitan areas defined by the Census in 1977 for the period 1962 to 1982. Estimation shows that all price elasticities are elastic and that the signs are as expected. These results hold true for virtually all model specifications. Our findings indicate that federal, state, and local tax policies have significant impacts on factor demand and output supply. Public investment plays a positive and significant, but small, role in increasing output and in complementing other factors, although this influence has declined over time. Additionally, capital provided by the private sector has a substantially larger impact on output and employment than does capital provided by the public sector.

Notes: Summary. Mortality from epithelial ovarian cancer is falling in women under 55 years of age in England and Wales. The decline does not appear to be a treatment effect nor to be attributable to changes in the rate of oophorectomy. Case-control studies have shown that high parity and oral contraceptive use are protective against the disease. We suggest that the decrease in mortality is compatible in timing and magnitude with exposure to oral contraceptives. No obvious effect on mortality attributable to parity was apparent in this analysis. Oral contraceptives may prove to be a widely acceptable means of preventing ovarian cancer, providing they do not increase breast cancer risk.

Notes: Summary. A method for estimating fetal weight by calculating an approximate fetal volume from abdominal area, head area and femur length has been developed. Birthweights were calculated within 48 h before delivery for 434 patients, using this method and two other methods already in widespread use. Statistical analysis of the three sets of predictions gave standard deviations of 297 g for the new method, compared with 323 g and 342 g for the other methods. Further analysis of the data showed that estimates closest to the true birthweight were obtained in 41% of cases by using the new method, and in 33% and 26% of cases using the other methods.

Notes: Following the statement concerning oral contraceptives containing oestrogens by the Committee on Safety of Drugs in December 1969, many women in England and Wales stopped taking oral contraceptives and it seems highly probable that thousands of unintended pregnancies occurred. By contrast, among 1328 women attending family planning clinics at Norwich and High Wycombe, no more than a handful of women discontinued oral contraception, and no accidental pregnancies occurred which could be attributed to the events occurring in December 1969.

Notes: The mortality trends from venous thromboembolic disease in England and Wales for the years 1953 to 1971 have been reviewed in the light of the results of epidemiological studies of the relationship between oral contraceptives and fatal venous thromboembolism, and the pattern of use of oral contraceptives. It is concluded that the mortality trends are compatible with the findings in the epidemiological studies, but that confirmation of a reduction in risk following the implementation of the recommendation by the Committee on Safety of Drugs in December I969 concerning oral contraceptives containing oestrogens must depend on other studies currently in progress.