A luminosity monitor system for the JETSET experiment at LEAR

A luminosity-monitor system for the JETSET experiment at LEAR is described. Four silicon-strip detectors are used as position sensitive devices to monitor the elastic p-scattering. The design concept, data-acquisition and results of the detector system are presented. On-line monitoring is used to assure the proper operation of the JETSET experiment.     

Research output and transnational cooperation in physics subfields: A multidimensional analysis

This paper compares the profiles of research output and transnational cooperation (as revealed through multicountry publications) of thirty six countries in ten subfields of Physics during the period 1981–1985. The data for comparative analysis were taken fromBraun et al. Since raw counts of publications are confounded by the size of the countries and the size of the research fields, this comparison is made, using relative indicators — activity index and collaboration index. The structures of research output and transnational cooperation are analyzed through Correspondence Analysis, which leads to the identification of countries with similar profiles (of research output and transnational cooperation) and the spatial representation of countries and Physics subfields. The configurations of research output and transnational cooperation are compared to assess the concordance between the policies of these countries for research and transnational cooperation in Physics.     

Simple baseband synchronisation scheme for tamed frequencymodulation

A novel carrier and clock synchronisation scheme for tamed frequency modulation is presented. It requires one complex sample per bit, like the digital Costas loop for offset in-phase and quadrature modulations, and is based on processing baseband samples of the phase of the received signal. The performance of the synchroniser is assessed by S-curves and simulated acquisition trajectories     

Continuously distributed phase shifts in chirped DFB lasers usingbent waveguides

The authors have implemented chirped distributed feedback (DFB) grating lasers with phase shifts [λ/8, 2λ/8 and 3λ/8] distributed continuously over various axial distances, using their recently proposed method for producing bent optical waveguides. The singlemode stability of the lasers with distributed phase shifts was found to be considerably higher than for lasers with abrupt phase shifts     

Experimental study of interzonal natural convection through an aperture

The work was concerned with measuring natural convection through an aperture between two zones in an environmental chamber. Airflow rates between the two zones were measured using a tracer-gas decay technique, and the temperature at the centre of each zone was measured using thermocouples. Zone 1 was heated to various temperatures in the range 18–38°C using thermostatically controlled heaters. Zone 2 was unheated. A multipoint sampling unit was used to collect a tracer-gas sample from each zone. The concentration of SF₆ tracer was measured using an infra-red gas analyzer. The heat and mass flow rates between the two zones were calculated from the tracer-gas concentrations and temperature differences. Results were compared with values predicted by existing algorithms for two-zone enclosures. The mass flow rate through the aperture was found to be a function of the temperature difference between the two zones.     

Activation of 5-HT2 receptors facilitates depolarization of neocortical neurons by N-methyl-D-aspartate

We prospectively studied 63 children with transient hyperglycemia to determine their risk of acquiring insulin-dependent diabetes mellitus (IDDM) and to evaluate the predictive value of immunologic markers of prediabetes and of the intravenous glucose tolerance test. Children with transient hyperglycemia were identified by a prospective systematic review of the laboratory reports of a large children's hospital and an office-based pediatric practice and by referral from pediatricians. Transient hyperglycemia occurred in 0.46% of children seen in the children's hospital and in 0.013% of children attending a pediatric office practice. Insulin-dependent diabetes mellitus developed within 18 months of identification in 32% of children in whom transient hyperglycemia was discovered in the absence of a serious illness, compared with 2.3% of children identified during a serious illness (relative risk, 13.9; 95% confidence interval, 1.56 to 123.5). Islet cell antibodies and competitive insulin autoantibodies each had a 100% positive predictive value for IDDM; the negative predictive value of islet cell antibodies and competitive insulin autoantibodies was 96% and 98%, respectively. The stimulated insulin release during an intravenous glucose tolerance test, adjusted for age, had the highest overall accuracy of prediction. All children less than 6 years of age with stimulated insulin release levels < 85 pmol/L (12 microU/ml) subsequently had IDDM, as did an 11-year-old child whose stimulated insulin release level was below the 1st percentile of 170 pmol/L (24 microU/ml). To date, no child whose stimulated insulin release level was above the 5th percentile has had IDDM. We conclude that when transient hyperglycemia occurs during a serious intercurrent illness, the risk of progression to IDDM is low. In contrast, one third of children in whom transient hyperglycemia is identified without a serious illness can be expected to have IDDM within 1 year. A combination of islet cell antibodies, competitive insulin autoantibodies, and stimulated insulin release levels during an intravenous glucose tolerance test can accurately distinguish children with prediabetes from those with presumed benign transient increases in plasma glucose concentrations.     

A growth control approach to Class II, Division 1 cases during puberty involving the simultaneous application of maxillary growth restriction and mandibular forward induction

A simple method that used headgear and a functional appliance simultaneously was used for the correction of Class II, Division 1 cases with severe denture base discrepancy. The treatment restricted the forward growth of the maxilla and advanced the mandible. The functional appliance, referred to as the mandibular growth advancer (MGA), advances the mandible progressively with a splint, with the objective of remodeling the condyle and the glenoid fossa in the temporomandibular joint. Functional adaptation was achieved as the muscles that are attached to the mandible adjusted to new positions. In the two cases that illustrate this method, the ANB angle decreased and the Ar-B distance increased over a short period to four and six times the mean Japanese growth rate, respectively. After the correction of the denture-base discrepancy, a multibracket fixed appliance was used for dental alignment, and good skeletal, occlusal relationships and profiles were obtained. Treatment of severe denture-base discrepancy in this manner may reduce the skeletal abnormality, decrease the number of extraction cases, and shorten the subsequent multibracket treatment time. And it may reduce the iatrogenic side effects caused by prolonged mechanotherapy with a fixed appliance.