Inductive definability in formal language theory

A concept of predicative inductive definability is introduced, where predicativity is restricted in a linguistically acceptable manner. This concept is in contrast to the monadic inductive definability inherent to all rewriting systems. The resulting grammars may be regarded as schemata for language-perception experiments; i.e., they are sets of instructions transforming strings where the whole process can be visualized in its entirety.     

Fatigue crack propagation in Stage I in an aluminum-zinc-magnesium alloy: General characteristics

Fatigue crack propagation in Stage I in an age-hardened Al-Zn-Mg alloy was investigated using notched single crystal specimens. In a dry nitrogen gas environment, propagation occurs almost exclusively in the primary slip plane and preferentially along favorably oriented crystallographic slip directions. The resulting fracture surfaces show increasing roughness with increasing propagation velocities; at small velocities (about 70⇘/ cycle) they appear like cleavage surfaces, whereas at large velocities (about 2000⇘/ cycle) they are associated with much more ductility and show a dimpled structure. These observations indicate that the plastic relaxation at Stage I crack tip increases with increasing velocities. In the presence of moisture in the test environment crack growth occurs at larger velocities giving rise to more reflective fracture surfaces. The moisture in the environment seems to be responsible also for the inter crystalline Stage I crack propagation observed in polycrystalline samples. Low stacking fault energy materials deforming by planar slip do not show a similar tendency to fracture in macroscopic slip bands.     

Augmentation of pentylenetetrazol induced seizures by tricyclic antidepressants

The effect of a brief appointment reminder for mental-health center applicants is reported. A standardized phone message was delivered by an administrative staff member one to three days before the appointment and a sequential experimental design alternating baseline and phone message conditions was used to assess the effects of the procedure. The no-show rate averages were 32%, 11%, 25%, and 14% respectively. The cost of the procedure was $162.00, which was totally recovered when only six appointments were kept. Since over 1000 patients were involved in the study, the return on the investment of +162.00 is considerable. Implications for this procedure are discussed for other community mental-health centers and for other community care-giving agencies.     

Hyphenation of capillary HPLC to microcoil (1)H NMR spectroscopy for the determination of tocopherol homologues

Highly selective reversed phases (C(30) phases) are self-packed in 250 microm inner diameter fused-silica capillaries and employed for capillary HPLC separation of shape-constrained natural compounds (tocopherol homologues, vitamin E). Miniaturized hyphenated systems such as capillary HPLC-ESI-MS (positive ionization mode) and, with special emphasis, continuous-flow capillary HPLC- NMR are used for structural determination of the separated compounds. Despite the small amount of sample available (1.33 microg of each tocopherol), the authors have been able to monitor the capillary HPLC separation under continuous-flow (1)H NMR conditions, thus allowing an immediate peak identification. Further structural assignment was carried out in the stopped-flow NMR mode as shown, for example, by a 2D (1)H,(1)H COSY NMR spectrum of alpha-tocopherol. We demonstrate in this paper the considerable potential of hyphenated capillary separations coupled to MS and NMR for the investigation of restricted amounts of sample.     

Verbund im Glasbau – Neues und Bewährtes

Laminated glass – novel and well‐tried. With increasing safety specifications, glass laminates become more important in the use of glass for structural elements. The requirements of laminated glass includes safety against fall arrest, post breakage behaviour and bomb blast resistance. In addition to the structural aspects, laminates of two or more glass panes are nowadays increasingly used for sound insulation, protection against direct or diffuse sunlight etc. Various design possibilities (coloured or printed interlayer, embedding of fabric, papers meshes etc.) are available for a wide range of architectural applications. Parallel to the rising requirements and possibilities of laminated glass, scientific studies concentrated on the mechanical properties of laminates with Polyvinylbutyral (PVB) interlayer and development of new interlayers by the industry. This article compares laminates with different interlayers and shows the results of scientific research.     

Expression of prolactin-related protein I at the fetomaternal interface during the implantation period in cows

The bovine placenta secretes multiple molecules during implantation and placentation, many of which are produced by binucleate cells. In this study, production of prolactin-related protein I (PRP-I), a member of the non-classical prolactin-related family, was investigated during the implantation period in cows. Expression of bovine PRP-I (bPRP-I) in the placentome was examined during the preimplantation (days 17-19), implantation (days 20-25) and post-implantation (days 30-60) periods by immunohistochemistry, immunofluorescence and in situ hybridization. During the preimplantation period, both bPRP-I and bovine placental lactogen (bPL) were undetectable in trophoblastic cells. Both bPRP-I mRNA and protein appeared first at day 20 of gestation in trophoblastic binucleate cells and multinuclear cells that might migrate into the endometrium and fuse to epithelium; however, no bPL was detected in binucleate cells at this time. After implantation, on day 30, both bPRP-I and bPL were detected in binucleate cells and were co-expressed in the same cells. These data indicate that bPRP-I may play a role before implantation and that bPRP-I may be an excellent marker for trophoblastic cell differentiation, as well as a candidate for pregnancy diagnosis.     

Reasons for and developments in international scientific collaboration: does an Asia–Pacific research area exist from a bibliometric point of view?

This paper describes the different forms of and tries to give reasons for international scientific collaboration in general. It focuses on eleven countries in the Asia–Pacific region by evaluating their national research output with the help of bibliometric indicators in particular. Over two million journal articles published by these countries between 1998 and 2007 in ISI-listed periodicals are analyzed. Discipline-specific publication and citation profiles reveal national strengths and weaknesses in the different research domains. The exponential increase in publication output by China over the last few years is astonishing, but in terms of visibility, i.e. citation rates, China cannot keep up with leading science nations, remaining below the world average. A discipline-specific analysis shows that Chinese authors took an active part in more than a quarter of all articles and reviews published in the field of materials science in 2007, while their contribution to medical research is very low. Co-publication networks among the eleven countries are generated to observe the development of cooperation bonds in the region. Applying Salton’s measure of international collaboration strength, an above-average strengthening of scientific collaboration in the Asia–Pacific region can be observed.