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This paper discusses in what sense an over-represented multi-word pattern in a corpus of translated texts can be said to be typical of translated text. The purpose of the discussion is to assess, from a quantitative as well as from a qualitative perspective, the status of translational collocation data retrieved through data-driven methods from a comparable and parallel aligned cor¬pus of English and Swedish original and translated texts. The study focuses on the explicitation of clausal relations in translations from English into Swedish. In some cases, lexical and grammatical contrast lead to explicita¬tion, but in others explicitation is due to different factors.

The local electronic structure of N atoms in Ga ( In ) AsN diluted alloys ( N concentration of 3%) is determined by soft-X-ray emission and absorption spectroscopies as element specific probes. The experimental spectra reflect the local 2p orbital-projected density-of-states of N impurities, the main recombination centers in Ga ( In ) AsN , which appears to deviate dramatically from crystalline GaN in both valence and conduction bands. In particular, we observe a N local charge transfer from the valence band maximum to deeper valence states, which fundamentally limits the optical efficiency of Ga ( In ) AsN , unless different N local environments are formed. The incorporation of In in large concentrations forms In -rich N local environments such as In 4 N , which become the main recombination centers in Ga ( In ) AsN due to a local decrease of the band gap. A k-conserving process of resonant inelastic X-ray scattering is discovered, which allows probing of the k-character of valence and conduction states despite the random alloy nature of Ga ( In ) AsN .

Systematic experimental data on resonant inelastic X-ray scattering (RIXS) in GaN near the N K-edge are presented for the first time. Excitation energy dependence of the spectral structures manifests the band structure effects originating from momentum selectivity of the RIXS process. This finding allows obtaining k-resolved band structure information for GaN crystals and nanostructures.

Surface science goes back to the beginning of the 19th century. It was, however, only with the development of ultra high vacuum (UHV) technology in the 1960,s that reproducible experimental results from surfaces on the atomic scale could be obtained. At about the same time high speed computers appeared which made it possible to apply realistic computations of surface properties. The last decade ha8 seen a large progress in surface 8cience and the field is under rapid development. This is largely due to the continuous development of the experimental and the theoretical methods. Many basic properties of surfaces are now in principle understood. Much more research is however necessary to achieve detailed descriptions, in particular of complex systems such as interfaces, overlayers and multilayers. A coordinated interplay between theory and experiment is desirable to achieve an efficient progress. In this article we will illustrate the present understanding of semiconductor surfaces as achieved mainly by photoelectron 8pectroscopy using synchrotron radiation. We will choose three examples, namely results from (i) core level studies on a clean surface, (ii) valence band studies of a clean surface, and (iii) core level and valence band studies on an adsorbate system. Before presenting these results we will summarise the present understanding of the atomic and the electronic structure of crystalline semiconductor surfaces.

As part of an extensive project on the surface electronic structure of semiconductor compounds we report here on an experimental and theoretical study of the InP(110) surface. By comparison of angle-resolved photoemission data with results from empirical tight-binding calculations it has been possible to identify electronic surface related features and specify their origin.

The electronic stucture of elemental solids, compounds and ordered alloys can today be calculated to a high accuracy by first principles theories, see for instance [1]. The translation invariance in such systems simplifles the description considerably. In disordered systems, e.g. substitutionally disordered alloys, this simplification is removed and the electron states cannot be described by conventional Bloch waves. The description of random alloys has been developed into quite sophisticated theories during the last 20 years, since the pioneering paper by Soven [2]. A central concept is the coherent potential approximation, CPA. This is a mean-field theory and one usually applies a single-site approximation. Advanced numerical methods have been developed to solve the CPA problem in a KKR formalism [3, 4]. Comparisons have been made with experimental density-of-states related functions obtained from e.g. photoelectron spectroscopy. However, the theory provides much more information than this. In particular, Bloch spectral densities A(k, E) are available for a number of alloy sy8tems. Only in a few cases however there have been attempts to correlate these data with experimental results. We believe that it is very important to make detailed comparisons between theory and experiment to test the present CPA theories. In the present work we focus our attention on a simple, but fundamental situation, namely a transition metal impurity in a free-electron-like host. The

The reflection–transmission method for determining the optical constants of a film on a substrate has been examined and a computer program for the solution of the equation system has been written. A new method involving only transmittance data in a limited wavelength region has been worked out and has been found to give accurate results. The computer program for this method gives directly n and k curves from the transmission curve.

High-resolution soft X-ray emission and absorption spectra near the N K-edge of wurtzite GaN are presented. The experimental data are interpreted in terms of band structure based full-potential electronic structure calculations. The absorption spectra, compared with calculations including core hole screening, indicate partial core hole screening in the absorption process. The resonant emission spectra demonstrate pronounced dispersions of the spectral structures, identifying effects of momentum conservation due to resonant inelastic X-ray scattering (RIXS) with anisotropic electronic structure of GaN. In view of a wide range of optoelectronic applications of GaN, our findings on the momentum selectivity in RIXS can be utilized in development of GaN based nanoelectronics devices by controlling direct vs indirect band gap character of GaN nanostructures., Comment: 9 pages, 7 figures, submitted to Phys. Rev. B

Soft-X-ray emission and absorption spectroscopies with their elemental specificity are used to determine the local electronic structure of N atoms in Ga(In)AsN diluted semiconductor alloys (N concentrations about 3%) in view of applications of such materials in optoelectronics. Deviations of the N local electronic structure in Ga(In)AsN from the crystalline state in GaN are dramatic in both valence and conduction bands. In particular, a depletion of the valence band maximum in the N local charge, taking place at the N impurities, appears as one of the fundamental origins of reduced optical efficiency of Ga(In)AsN. Incorporation of In in large concentrations forms In-rich N local environments such as In4N whose the electronic structure evolves towards improved efficiency. Furthermore, a k-character of some valence and conduction states, despite the random alloy nature of Ga(In)AsN, manifests itself in resonant inelastic X-ray scattering., Comment: Major revisions (including new experimental data), 7 pages, 3 Postscript figures, accepted by Phys. Rev. B

Excited-state self-energy effects in the electronic structure of Cu, a prototype weakly correlated system containing states with different degrees of localization, are investigated with emphasis on the unoccupied states up to 40 eV above the Fermi level. The analysis employs the experimental quasiparticle states mapped under full control of the 3-dimensional wavevector k using very-low energy electron diffraction for the unoccupied states and photoemission for the occupied states. The self-energy corrections to the density-functional theory show a distinct band- and k-dependence. This is supported by quasiparticle GW calculations performed within the framework of linearized muffin-tin orbitals. Our results suggest however that the GW approximation may be less accurate in the localized d-bands of Cu with their short-range charge fluctuations. We identify a connection of the self-energy behavior with the spatial localization of the one-electron wavefunctions in the unit cell and with their behavior in the core region. Mechanisms of this connection are discussed based on the local-density picture and on the non-local exchange interaction with the valence states., 8 pages, 6 Postscript figures, accepted by Phys. Rev. B; typos corrected

The local electronic structure of N atoms in a diluted GaAs1-xNx (x=3%) alloy, in view of applications in optoelectronics, is determined for the first time using soft-X-ray absorption (SXA) and emission (SXE). Deviations from crystalline GaN, in particular in the conduction band, are dramatic. Employing the orbital character and elemental specificity of the SXE/SXA spectroscopies, we identify a charge transfer from the N atoms at the valence band maximum, reducing the overlap with the wavefunction in conduction band minimum, as the main factor limiting the optical efficiency of GaAs1-xNx alloys. Moreover, a k-conserving process of resonant inelastic x-ray scattering involving the L1 derived valence and conduction states is discovered., Comment: 3 pages, physica status solidi (Rapid Research Notes), in press

We present an experimental method to determine the electronic Eskd band structure in crystalline solids absolutely, i.e., with complete control of the three-dimensional wave vector k. Angle-dependent very-low-energy electron diffraction is first applied to determine the unoccupied states whose k is located on a high-symmetry line parallel to the surface. Photoemission via these states, employing the constant-final-state mode, is then utilized to map the valence bands along this line. We demonstrate the method by application to Cu, and find significant deviation from free-electron-like behavior in the unoccupied states, and from density-functional theory in the occupied states. [S0031-9007(98)07792-8]

The con~plex dielectric function of thin Cu-Ag alloy films has been determined from optical transmittance measurements. The electronic structures of the three noble metal-noble metal alloys are found to be qualitatively the same, in contrary to earlier findings.

Thyroid glands from 64 bulls with hyperplastic and/or neoplastic changes in ultimobranchial remnants and in the parafollicular (C) cell system were studied structurally and with immunohistochemical methods. Antibodies against thyroglobulin, calcitonin, somatostatin, and neurotensin were used to detect these substances. Two different types of changes were observed. One change was hyperplasia and neoplasia of the ultimobranchial remnants that affected all their epithelial constituents. These included ultimobranchial follicles, cysts and tubules, as well as solid nests formed by basophilic immature cells which were functionally undifferentiated and unreactive with all the antisera used. Differentiated follicular cells that formed thyroid follicles and cribriform structures with immunohistochemical evidence of thyroglobulin production were also found. In addition, differentiated light and cytoplasm-rich cells were scattered in the walls of the thyroid follicles, ultimobranchial follicles, cysts and tubules as well as in the solid component. They were argyrophilic and reacted with antibodies against calcitonin and somatostatin. The other change was a diffuse or multifocal hyperplasia of the parafollicular (C) cells that was present in other parts of the thyroid parenchyma—sometimes with gradual development of sclerotic tumors that had been exclusively formed by these cells. They corresponded to light cytoplasm-rich cells seen in the ultimobranchial lesions that were argyrophilic and harbored material reactive with antibodies against calcitonin and/or somatostatin. The changes observed in the parafollicular cell system resembled lesions seen in human thyroid glands with the familial variant of medullary carcinoma as well as those reported in thyroid glands of patients with longstanding hypercalcemia. Bull ultimobranchial tumors closely resembled a recently defined, intermediate type of human differentiated thyroidal carcinoma that has traits of both medullary and follicular carcinoma.

In a case of abortion in swine pure cultures of Staph, aureus were obtained from various organs of 13 aborted foetuses. Specimens of the placenta and uterine secretion yielded virtually pure growth of Staph, aureus. The isolated strains showed identical biological properties and an identical phage-pattern. The staphylococcal infection is considered to have been the primary cause of the abortion. Possible paths of infection are discussed. Vid ett fall av abort hos svin pavisades Staphylococcus aureus i renkultur i olika organ hos 13 aborterade foster. I efterbord och uterussekret pavisades ocksa Staphylococcus aureus i praktiskt taget renkultur. De isolerade stafylokockstammarna visade identiska biologiska egenskaper och identiskt fagmonster. Stafylokockinfektionen anses vara den primara kastningsorsaken. Mojliga infektionsvagar diskuteras.

Blood levels of calcitonin (CT), calcium (Ca), inorg. phosphate (P) and alkaline phosphatase (ALP) in 27 bulls of Swedish Red and White Breed (SRB) and 21 Swedish Friesian Breed (SLB) were studied. There was a significant lowering of Ca, P, ALP and CT with increasing age. The fact that the osteopetrotic syndrome is increasing with age in bulls and that the CT level in blood is decreasing with age does not support the idea that an increased CT discharge could be responsible for the osteopetrotic syndrome in bulls.

Autopsy studies of the thyroid gland in lactating cattle were combined with chemical tests of thyroid function, i.e. protein-bound iodine (PBI) in serum, and uptake by the erythrocytes in vitro of I(131)-labelled L-triiodothyronine (EU). The study was made on 255 cows from 5 different slaughterhouses in Sweden. To permit a comparison with the chemical results, the thyroids were classified morphologically as normal, slightly changed, and moderately to greatly changed, respectively. The term goitre was used to denote those glands whose weight exceeded 54 g in SRB cows, 51 g in SLB cows, and 44 g in SKB cows. Examination of glands from cows in the Sundsvall region showed 85 % to be the site of histological changes, which were denoted as moderate to marked in 72 % of them. The corresponding figures for the Östersund region were 68 and 28 %, respectively. In the other sampling regions, the figures ranged from 40—52 % and from 21—28 % respectively. Totally 12 thyroids were found to be goitrous; 5 of them derived from the Sundsvall region, and 3 from the Östersund region. All but 2 of the cows with goitre were chemically euthyroid. Cows from the Sävsjö, Östersund and Halmstad regions had significantly lower EU values than cows from the Uppsala and Sundsvall regions. No corresponding difference was present between the various regions with respect to PBI. Cows with morphologically changed glands had higher PBI values than cows with morphologically normal glands. There was a poor correlation between the nature of the histological change and the results of the chemical analyses.