Lithium conducting solid electrolyte Li1.3Al0.3Ti1.7(PO4)3 obtained via solution chemistry

NaSICON-type lithium conductor Li_1.3Al_0.3Ti_1.7(PO₄)₃ (LATP) is synthesized with controlled grain size and composition using solution chemistry. After thermal treatment at 850 °C, sub-micronic crystallized powders with high purity are obtained. They are converted into ceramic through Spark Plasma Sintering at 850–1000 °C. By varying the processing parameters, pellet with conductivities up to 1.6 × 10^?4 S/cm with density of 97% of the theoretical density have been obtained. XRD, FEG-SEM, ac-impedance and Vickers indentation were used to characterize the products. The influence of sintering parameters on pellet composition, microstructure and conductivity is discussed in addition to the analysis of the mechanical behavior of the grains interfaces.     

Ultra-low drift microwave cryogenic oscillator

The operation of a microwave cryogenic sapphire resonator oscillator presenting an exceptional frequency stability for long integration times has been demonstrated. Based on a very simple design the 11.5 GHz oscillator presents a fractional frequency instability lower than 6/spl times/10/sup -14/ over one day.     

Trypanosoma cruzi infection in mice induces a polyisotypic hypergammaglobulinaemia and parasite-specific response involving high IgG2a concentrations and highly avid IgG1 antibodies

Trypanosoma cruzi infection in BALB/c mice induced a reversible polyisotypic hypergammaglobulinaemia, with particularly high levels of IgG2a, IgM and IgE. Hypergammaglobulinaemia started during the acute phase of infection and persisted during chronic disease until 11-13 weeks post-infection (w.p.i.), when immunoglobulin levels, with the exception of IgE, returned near normal values. Parasite-specific antibodies counted for 14 to 23% of gammaglobulinaemia, in acute and chronic infection respectively. The titres of IgM antibodies rose from two w.p.i. IgA, IgE and IgG subclass antibodies built up gradually over the time of parasite clearance (i.e., between three and six w.p.i.). All antibody isotypes, including IgM reached significant and stable titres throughout chronic infection. IgG2a, IgG1 and IgM antibodies had constantly higher titres than the other antibody isotypes. The dominance of IgG2a antibodies was due to their high plasma concentrations, around 70% of all antibodies available in the chronic infection. IgG1 had the highest functional avidity, whereas its concentration corresponded to only 10% of the whole antibody fraction. These results indicate that T. cruzi infection in mice induces a polyisotypic humoral immune response, dominated by some antibody isotypes, with major differences in concentrations and functional avidities. This could be of crucial importance in determining the outcome of infection.     

Samnos technology

The SAMNOS technology permits to fabricate insulated field-effect transistor having a self-aligned gate, reduced capacitance, and lower surface step height. A silicon nitride layer serves first as a diffusion mask, then as an oxidation barrier, and ultimately as a gate dielectric.     

A large solid-angle array for heavy ions from APEX

A large solid-angle array of Low Pressure Multi-Wire Proportional Counters (LPMWPCs) has been constructed as part of the ATLAS Positron Experiment (APEX). Eight three-element trapezoidal counters span 360° in φ and 20–68° in laboratory θ. Angle sensitivity in θ is provided by a transmission-line delay cathode, while the 24-fold segmentation provides angle sensitivity in φ. Details are given on the design of the counters and associated hardware. Performance of the counters is described, based on tests with scattered heavy ions ranging from ⁵⁸Ni to ²³⁸U.     

Assessment of postoperative pain after laryngeal surgery for cancer

OBJECTIVES: To assess the intensity of postoperative pain after laryngeal surgery for cancer and the efficacy of analgesic injections at fixed hours. DESIGN: A prospective clinical study performed during the 3 days following laryngeal cancer surgery. SETTING: A university medical center. PATIENTS: Fifteen men (age range, 38-74 years) having just undergone a partial or total laryngectomy for epidermoid carcinoma. INTERVENTIONS: The analgesic treatment consisted of intravenous administrations at fixed hours (propacetamol or nalbuphine hydrochloride), with the possibility of rescue doses on demand. Pain and anxiety were assessed by means of visual analog scales (graduated from 0-10) every 3 hours on postoperative day 1, then every 6 hours on postoperative days 2 and 3. Objective criteria, ie, heart and respiratory rates and mean blood pressure, were measured with the same schedule. MAIN OUTCOME MEASURES: Postoperative pain and anxiety intensities and their variations were analyzed. Correlations between postoperative pain and other criteria were researched. RESULTS: Postoperative pain had a high initial level (maximum median, 7), then decreased and reached a score of 3 at the 30th hour. Unpredictable individual peaks of pain were reported. Anxiety was never high (maximum median, 4). No individual correlation was found between pain and objective parameters. CONCLUSIONS: After laryngeal surgery for cancer, pain can reach high levels, particularly in the first hours following recovery. Analgesic administrations at fixed hours are not effective enough. Postoperative analgesic treatment should aim to prevent the high initial pain and be individually adapted.     

Effects of etomidate, propofol and thiopental anaesthesia on arteriolar tone in the rat diaphragm

We have assessed, by intravital microscopy in rats, the effects of different anaesthetics on diaphragmatic arteriolar diameter. Rats were anaesthetized with etomidate, propofol or thiopental (groups E, P and T, respectively) and the diameters of the arterioles were measured sequentially at baseline and after topical application of either mefenamic acid (MA, 20 mumol litre-1) or N omega-nitro-L-arginine (NNA, 300 mumol litre-1), inhibitors of prostaglandins and nitric oxide, respectively. In group E, baseline arteriolar diameters were significantly higher than those in the two other groups (P < 0.01). MA and NNA induced significant constriction in the three groups (P < 0.001). However, whereas constriction induced by NNA was similar in the three groups, constriction induced by MA was significantly higher in group E compared with groups P and T (P < 0.05). We conclude that diaphragmatic arteriolar diameters in rats were greater during etomidate than during thiopental or propofol anaesthesia. This phenomenon may be mediated by prostaglandins.     

A tubular bioreactor for photosynthetic production of biomass from carbon dioxide: Design and performance

A theory of photobioreactor design is developed. A photobioreactor was constructed in the form of a loop made from 52 m of glass tubing of 1 cm bore; the loop covered about 0.5 m². The culture was illuminated with mercury halide lamps to reproduce sunlight. Computer control was used to maintain constant biomass concentration. The influence of radiation on the reactor temperature is quantitatively predicted. An air lift system was preferred to a liquid pump for culture recycle. The energy required for culture recycle in the loop with Reynolds number 2000 was 0.6 W m^?2. The CO₂ gas/liquid transfer rate achieved was sufficient to meet the maximum possible demand with solar irradiation. The O₂ gas/liquid transfer rate was sufficient to meet the maximum respiration demand at night. The maximum algal biomass concentration achieved exceeded 20 g dry weight litre^?1. A biomass concentration of 8 g dry weight litre^?1 was found to be convenient for normal operation. The maximum uptake of light in the available wavelength range (400–700 nm) was 38 W m^?2, this corresponds to utilisation of solar irradiation up to 89 W m^?2. Below the maximum light uptake rate the efficiency of storage of light energy in the biomass corresponded to 16.6% of solar energy.