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Sr0.5Ba0.5Si2O2N2:Eu2+ is a promising new phosphor for white light phosphor converted (pc)—LEDs. The material shows broad-band emission due to parity allowed 4f6(7F)5d → 4f7(8S7/2) transition in the yellow spectral range (λem ≈ 560 nm) while excited with UV to blue radiation. The X-ray powder diffraction pattern shows noticeable intensity maxima indicative for diffuse scattering from planar defects and also “missing” reflections compared to SrSi2O2N2:Eu2+. Rietveld refinement reveals an average structure of Sr0.5Ba0.5Si2O2N2:Eu2+ which is isotypic to that of SrSi2O2N2:Eu2+, with the latter representing a twinned layered oxonitridosilicate with disordered metal atoms. The average structure of Sr0.5Ba0.5Si2O2N2:Eu2+ was refined in space group P1 (no. 1) resulting in lattice parameters a = 7.2059(2), b = 7.3887(3), c = 7.3340(2) A, α = 88.524(4), β = 84.454(3), γ = 75.980(4)° and V = 377.07(2) A3. Based on the crystallographic results and considering lattice relaxation behavior as a consequence of lattice expansion, the observed unexpectedly large Stokes shift (as compared to SrSi2O2N2:Eu2+; 3573 vs. 3285 cm−1) can be explained using a least square fit of the emission spectra. With almost identical chromaticity coordinates with respect to the most frequently used commercial LED phosphor YAG:Ce3+ but significantly higher luminous efficacy (LE = 495 lm/W), Sr0.5Ba0.5Si2O2N2:Eu2+ is a promising material for outdoor lighting, e.g. in cool-white pc-LEDs. To elucidate the real structure, powder XRD simulations have been recorded compiling a disorder model taking into account all permutations of metal ion sets and silicate layer orientations. Experimental diffraction data were well reproduced including the diffuse intensities observed in powder XRD and also in SAED patterns. These simulations show that crystallites of Sr0.5Ba0.5Si2O2N2:Eu2+ are built up of small anti-phase domains within larger twin domains.

Abnormalities in both quality of life and cognitive measures have been well-documented in women with Turner Syndrome (TS). Additionally, shyness and social anxiety appear to be common clinical features of TS. However, few studies have systematically examined the presence of mood and behavior syndromes in these women. In this chapter we report our recent studies on the psychological and social aspects of Turner syndrome in adult women. Overall, rates of psychiatric syndromes were not higher in women with TS than in women attending gynecologic clinics. Nonetheless, premature ovarian failure was associated with depression, reduced self-esteem and impaired social functioning. Elucidation of the specific mechanisms of this effect and identification of the women at particular risk are important areas for further study. Attention to psychological health and social functioning should be an important part of the care for women with premature ovarian failure, regardless of the underlying disorder.

Summary Mice investigated in this study were generated by selecting a sub-population of the NMRI out-bred stock (C), for high (H) or low (L) 8-week body weight. After 58 generations of selection, 8-week body weights of the sub-populations were markedly different if compared to controls. To investigate endocrine changes causing the altered growth performance in the different lines of mice, we analysed several components of the growth hormone (GH)/insulin-like growth factor (IGF) system. Pituitary weights of male and female L mice were significantly smaller than those of C and H mice. Relative to body weight, pituitary weights of male mice from the three lines did not differ, however pituitary weight-to-body weight-ratios of female L mice were significantly greater than those of H females. Mean volume densities of somatotropic cells were significantly smaller in L mice than in C and H mice. Serum IGF-I concentrations were significantly lower in the L line than in the C and H lines. H mice displayed significantly increased serum insulin levels both after ad libitum feeding and after a 14 hour fasting period. Ligand blot analysis of serum IGF-binding proteins (IGFBPs) revealed a significant reduction of circulating IGFBP-3 in L mice as compared to C and H mice. In contrast, serum IGFBP-2 mRNA levels were significantly increased in male L mice and showed non significant increases in female L mice. Hepatic IGFBP-2 mRNA levels were significantly increased in L mice and decreased in H mice as compared to C mice. Expression of IGFBP-4 mRNA in the liver was significantly decreased in both selection lines (L, H) as compared to the random-bred controls. Our findings demonstrate that altered growth of mice resulting from selection for body weight is associated with complex changes in the endocrine network of the GH/IGF system.

Summary A hitherto unknown skeletal muscle disorder is described in six Braunvieh × Brown Swiss calves. The animals showed rapidly progressing muscular weakness and became recumbent within 2 weeks of birth. Histological examination of skeletal muscle revealed a marked variation in muscle fibre size, internally placed nuclei, segmental loss of cross-striation with disorganization of myofibrils, and accumulation of nemaline rods. The most distinctive histological finding was intracytoplasmic, homogeneous, mostly crescent-shaped areas at the periphery of numerous muscle fibres. Electron microscopically, accumulations of tightly packed, parallel filamentous structures, about 20 nm in diameter, were detected in these areas. Enzyme histochemistry showed that all muscle fibre types were affected. Vimentin and dystrophin immunohistochemistry revealed normal antigen distribution within connective tissue components and at the periphery of each muscle fibre, respectively. The lesions could be readily distinguished from other neurological and neuromuscular disorders previously described in Braunvieh × Brown Swiss or American Brown Swiss cattle. The disease appears to be a novel congenital myopathy in this breed, and a hereditary aetiology is suspected.

Four formulations of the equine herpesvirus type 1 (EHV-1) glycoprotein gp14 (gB), were tested for their ability to protect mice against intranasal (inas) EHV-1 challenge infection. The preparations tested included (i) a truncated gp14 produced in Escherichia coli or (ii) a truncated gp14 expressed in insect cells by a recombinant baculovirus, (iii) truncated gp14 coexpressed with human immunodeficiency virus type 1 (HIV-1) gag virus-like particles (VLP) in insect cells, and (iv) a gp14-DNA vaccine under the control of the cytomegalovirus immediate early promoter. All antigen preparations and the DNA vaccine elicited a humoral and delayed-type hypersensitivity (DTH) immune response to EHV-1 after intramuscular (im) immunization. After inas immunization, only the VLP-gp14 preparation produced both a good humoral and a prominent DTH immune response; gp14 expressed by insect cells elicited high titers of EHV-1-specific antibodies, whereas gp14 produced in E. coli and the DNA vaccine elicited only low antibody titers. Glycoprotein gp14 expressed by bacteria, however, induced a strong DTH reaction after inas application. Mice were completely protected against EHV-1 challenge infection after both the im and the inas immunization with the VLP-gp14 preparation. Protection was less efficient after immunization with the E. coli and insect cell gp14s as well as after DNA vaccination. Although the transmembrane domain of EHV-1 gp14 was deleted, recombinant Gp14 could be demonstrated in insect cell membranes at late times postinfection and aggregated with the VLPs. It is suggested that the transmembrane domain is not required for gp14-association with membranes in that system.

Summary The detection of equine herpesvirus type 1 (EHV-1) in infected cell cultures, and in tissues taken at necropsy, by the in-situ hybridization technique is described. A 4·9 kb Bam HI fragment of EHV-1 vaccine strain RacH was used as a probe after labelling with [α- 32 P] thymidine 5’-triphosphate ([ 32 P]TTP) or digoxigenin-deoxyuridine 5’-triphosphate (dlUTP). Both probes specifically detected EHV-1 DNA in either cytospin or paraffin wax-embedded preparations of infected cells. The digoxigenin-labelled probe was further used to examine tissue sections of equine fetuses which had been aborted due to EHV-1 infection. In all cases positive hybridization signals were mainly associated with the nuclei. Positive results were confirmed by immunostaining of EHV-1 antigen in adjacent sections. However, both methods failed to detect EHV-1 in spinal cord sections of six horses suffering from disseminated necrotizing myeloencephalitis (DNM). These results support the hypothesis that DNM is not caused by a productive viral infection of parenchyma of the nervous system but is immunologically mediated.