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Double-shear steel-to-timber joints of beech laminated veneer lumber (LVL) with slotted-in steel plates using very high strength steel (VHSS) dowels have been investigated. Tensile tests on full-scale joints with one, two, three and six dowels have been carried out, using both VHSS and mild steel dowels. The goal of the research was to investigate the mechanical behaviour of joints of beech-LVL, with regard to load-carrying capacity (LCC), ductility, stiffness; and to find out whether the current design rules of Eurocode 5 are suitable for LVL and VHSS steels. Other examined aspects were the effect of multiple fasteners in a row and the influence of fastener steel grade. Tests showed higher values of joints with VHSS dowels, characterized generally by low scatter. The prediction ability of Eurocode 5 has been found to be inadequate and too conservative. A proposal for improvement is included., Steel & Composite Structures

Cerebrotendinous xanthomatosis (CTX) is a rare neurometabolic disease due to defective activity of sterol 27-hydroxylase, with plasma and tissue cholestanol storage. Clinical phenotype is characterized by both systemic manifestations and neurological signs. Therapy with chenodeoxycholic acid (CDCA) suppresses abnormal bile acid synthesis. The purpose of the study was to assess the frequency and clinical relevance of spasticity in the CTX phenotype and to study the usefulness of transcranial magnetic stimulation (TMS) in detecting corticospinal tract damage and monitoring the effects of replacement therapy. Twenty-four CTX patients underwent clinical evaluation including general disability scores, pyramidal and cerebellar function scales, assessment of serum cholestanol and TMS. Nine patients who started CDCA therapy at baseline received clinical and neurophysiological follow up. All patients showed signs of pyramidal damage which were relevant for clinical disability in 18 out of 24 cases (75%), resulting in spastic paraparesis. TMS revealed corticospinal alterations even in subjects with mild clinical signs of corticospinal tract involvement. After CDCA treatment, serum cholestanol decreased to normal concentrations in all patients. Clinical picture was unchanged in seven out of nine cases; in two others pyramidal signs disappeared. A reduction in abnormal neurophysiological parameters was found. Spastic paraparesis is the most frequent and relevant neurological feature in CTX patients. Replacement treatment with CDCA can prevent the progression of pyramidal damage, especially if started early in the course of the disease. TMS represents a sensitive indicator of corticospinal tract dysfunction and subclinical improvements in pyramidal function after CDCA therapy.

The use of the Soft X-ray Contact Microscopy technique is discussed as a possible new tool to get information on dopant distribution in the core of single-mode optical fibers with 50 nm spatial resolution.

The possibility of a pressure monitoring system by differential pressure sensors to detect contaminant effects on cellular cultures metabolic activity is discussed using Saccharomyces cerevisiae, lymphocyte, and AHH1 cell cultures. Metabolic (aerobic and anaerobic) processes in cells are accompanied by CO2 production that induces changes in pressure values when cells are cultured in sealed vessels. These values are subsequently converted in voltage units and plotted pressure dynamics versus time. This procedure leads to a standard curve, typical of the cellular line, which characterizes cellular metabolism when all parameters are controlled, such as temperature and nutrients. Different phases appear in the S. cerevisiae differential pressure curve: an initial growth up to a maximum, followed by a decrement that leads to a typical "depression" (pressure values inside the test-tubes are lower than the initial one) after about 35 h from the beginning. The S. cerevisiae differential pressure curve is successfully used to test the effects of chemical (Amuchina(R), trieline) and physical (UV radiation, blue light, magnetic fields) contaminants. The same technique is applied to lymphocytes and AHH1 cultures to investigate the effects generated by a 72-h exposure to a 50-Hz, 60-muT electromagnetic field. Lymphocyte samples, cultured in a PHA medium, grow less than control ones, but exhibit a greater metabolic activity: changes in the exposure system configuration influence neither sample growth differences nor metabolic response variations between control and irradiated samples, while all the other irradiation parameters remain constant. Control and irradiated lymphocyte samples, without PHA in culture medium, show the same behavior both during irradiation and metabolic test. AHH1 control and irradiated samples show no difference both in growth percentage during irradiation and in metabolic activity. Different cell cultures respond to the same stimulus in different manners.

The results are discussed of a systematic investigation into the electromagnetic held (EMP) exposure consequences on human lymphocytes. These artificial fields have intensities comparable to the Earth's magnetic field, and are used for exposures up to 4 days. Different and complementary techniques are used to safely assess the consequences of EMFs on the cells; in particular, morphology, metabolism, and population dynamics are investigated. The recourse to ultramicroscopy, pressure monitoring in sealed bottles, atomic mass spectroscopy, and cytofluorimetry techniques give good insight into the EMF-induced changes. A statistically significant deviation of irradiated samples with respect to control samples is reported. A critical analysis and a survey of similar experiments reported in the literature led us to examine the experimental setup with attention to the geometry of the irradiation system. Yeast cells were used as a model system to statistically test the different steps in the overall procedure, thanks to information gathered during a radiobiology experiment performed at the Rutherford Appleton Laboratory. Finally, the role of different magnetic field detectors in the reproducibility of the experiments is carefully discussed.