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Starting from Germany, the VFT bridge girder technology (prefabricated composite beam) has spread in several European countries in the last decades as further development of the standard steel‐concrete composite solution. Its configuration fits perfectly to integral frame bridges built over existing infrastructure with the scope to minimize the traffic disturbance. In this paper a further development with the focus on cost efficiency in span ranges of 40‐55 m is proposed: the RS‐Overpass technology. The change consists in using standard rolled sections by adapting them into the integral frame bridge configuration, further enhancing the structural efficiency with the benefits of high‐steel strength. The constructive details to achieve the polygonal form have been studied to allow easy fabrication and a maximal clearance height over highway traffic lanes. The RS‐Overpass solution is conceived as the economic option of standard highway overpasses, with the aim of a overall construction cost reduction of 5%. The possibility of weathering steel or hot‐dip galvanization create the unique offer for a maintenance‐free solution. [ABSTRACT FROM AUTHOR]

The introduction of composite dowels (CDs) in Europe at the beginning of the last decade led to the creation of new forms of composite bridges in which a T‐profile is used instead of an I‐beam. Both the construction and design methods are new [4]. Experiences from the construction of new bridges and discussion between the authors lead to new significant conclusions, which should be included in the new European approval (CEN‐TS). The problem of design formulas for concrete dowels is presented. [ABSTRACT FROM AUTHOR]

The measurement and analysis of residual stresses has gained significant importance over the past couple of years due to the increasing demands in improving the properties of new engineering materials and components. The ability to measure these residual stresses accurately will thus lead to the manufacture of stronger, lighter, and cheaper components by industry. The drive to optimize material performance whilst minimizing component weight will ensure that this field continues to grow. Experimentally, non-destructive analysis of phase-specific residual stresses is only possible by means of diffraction methods. While X-ray scattering is essentially a surface method, the high penetration depth of neutrons into the bulk material (e.g., 20 mm into steel or 100 mm into aluminium) allows extracting reliable information from the inside of components. [ABSTRACT FROM AUTHOR]

Abstract: We propose a supersymmetric model, where the quarks and leptons live in a product group theory space that is compactified on the real projective plane . The fermion generations are placed on different points in the deconstructed manifold by assigning them compatible charges. The observed masses and mixing angles of quarks and leptons emerge from non-renormalizable operators involving the chiral link fields. The link fields introduce a large atmospheric neutrino mixing angle via a dynamical realization of the seesaw mechanism, which sets the deconstruction scale to a value of the order the usual breaking scale ∼1014 GeV. Supersymmetry breaking can be achieved through topological effects due to a nontrivial first homology group . The mixed anomalies of the link fields are canceled by Wess–Zumino terms, which are local polynomials in the gauge and link fields only. We also comment on the construction of Chern–Simons couplings from these fields. [Copyright &y& Elsevier]

An intravertebral vacuum phenomenon was observed within 19 vertebrae of 17 patients. It represents a non-healing vertebral fracture. Three possible pathologic mechanisms are discussed: ischemic bone necrosis, trauma with ensuing ischemic necrosis, and intraosseous disc prolapse. The intravertebral vacuum phenomenon was found in two patients with multiple myeloma and thus does not exclude the presence of malignancy in the affected bone. Radiographs obtained during traction or extension may be of diagnostic value. [ABSTRACT FROM AUTHOR]

For the diagnosis of primary osteoporosis, various semiquantitative radiologic methods were compared in 149 unselected patients, aged over 50 years. Crush fracture syndrome (CFS), lumbar spine index (LSI), and Singh Index (SI) were assessed by three radiologists and after reevaluation, the intra- and interobserver errors were calculated. The reliability of the subjective grading was improved by joint and repeated reading of the radiographs. Additionally, the peripheral trabecular bone content was measured by photonabsorptiondensitometry (PAD). To test the value of the various semiquantitative methods, LSI, SI, and PAD have been compared with sex-matching before and after separation into age in decades in CFS-positive and CFS-negative patients. In an attempt to differentiate osteoporotics and non-osteoporotics by CFS, our results indicate that CFS-positive and CFS-negative males cannot be separated by LSI, SI, and PAD, whereas in females these methods can discriminate irrespective of the age in decades. However, in age related groups, only SI can discriminate significantly between CFS-positive and CFS-negative females. Correlation of the semiquantitative methods, regardless of the diagnosis of a CFS, revealed a significant correlation-between SI and PAD, but no correlation between LSI and SI, and LSI and PAD, respectively. [ABSTRACT FROM AUTHOR]

Magnetic resonance imaging (MRI) has emerged as complementary imaging modality to conventional radiography. The same diagnostic rules that are used in the interpretation of the routine radiographs should be applied to the analysis of MR images with the macroscopic spread of the disease as a main diagnostic clue. MRI has been shown to be a sensitive tool in detecting early arthritic changes and erosions, inflammation in periarticular tendons and tendon sheaths, and in juxtaarticular bursae. MRI plays a pivotal role in diagnosis of arthritis of the craniocervical junction and its complications. It also has been used effectively to detect insufficiency fractures and osteonecrosis. MRI may be important in diagnosing early arthritis, in specifying the differential diagnosis of rheumatic disease, and in selecting subgroups of patients to provide tailored therapeutic regimens [ABSTRACT FROM PUBLISHER]

Abstract: We present a six-dimensional Higgsless Standard Model with a realistic gauge sector. The model uses only the Standard Model gauge group with the gauge bosons propagating in flat extra dimensions compactified on a rectangle. The electroweak symmetry is broken by boundary conditions, and the correct splitting between the W and Z gauge boson masses can be arranged by suitable choice of the compactification scales. The higher Kaluza–Klein excitations of the gauge bosons decouple from the effective low-energy theory due to dominant brane kinetic terms. The model has the following two key features compared to five-dimensional models. The dimensional couplings in the bulk Lagrangian, responsible for electroweak symmetry breaking using mixed boundary conditions, are of order the electroweak scale. Moreover, with respect to “oblique” corrections, the agreement with the precision electroweak parameters is improved compared to five-dimensional warped or flat space models. We also argue that the calculability of Higgsless models can be ameliorated in more than five dimensions. [Copyright &y& Elsevier]