Microstructure/Process Relations in Sol-Gel-Prepared KnbO3 Thin Films on (100) MgO

Epitaxial (110) orthorhombic KNbO₃ thin films were prepared using alkoxide solutions. Single-phase films were produced with stoichiometric sols while slight variations in stoichiometry (52/48 Nb/K or 48/52 Nb/K) created residual second phases. Nucleation and growth of KNbO₃, as a function of process conditions were monitored by observing the KNbO₃ rosettes produced from niobium-rich solutions. Methanolic solutions produced films with the highest rosette density and the highest amount of KNbO₃. Hydrolysis of the sol aided the crystallization of the KNbO₃ phase but also promoted the formation of second phases. Hydrolysis at 0°C reduced second-phase formation.     

Antiproton-proton mass comparison with a radio-frequency mass spectrometer

The experiment aims at the reduction of the upper limit on a hypothetical CPT violation in the antiproton-proton system. A radio-frequency mass spectrometer (RFMS) has been designed and built to make the comparison of the charge to mass ratios of and p by measuring the ratios of the cyclotron frequencies of and H⁻ ions. At present, the RFMS is installed on-line to the LEAR facility at CERN. The resolving power has been found to be close to 3 × 10⁵ and it still could be improved. A decelerating system (RFQ) has been installed in order to decelerate antiprotons from 2 MeV to 200 keV and to match as well as possible the acceptance of the spectrometer. It is presently under test and data taking should take place in 1992.     

With regard to "The role of air plethysmography in monitoring results of venous surgery"

By homology to the mgt gene (encoding a macrolide glycosyltransferase) from Streptomyces lividans, a 3.3-kb DNA fragment from the oleandomycin producer, Streptomyces antibioticus, was cloned and sequenced. Analysis of the sequence revealed the presence of the 3' end of a gene (ORF1) and two complete ORFs (ORF2 and oleD), all of them translationally coupled. The deduced product of the sequenced region of ORF1 contained the typical signature of integral membrane proteins responsible for the translocation of substrates across the membrane. The ORF2 product did not show significant similarity with proteins in databases, but contains an N-terminus leader peptide region characteristic of secreted proteins, and a lipid attachment site motif characteristic of membrane lipoproteins synthesized with a precursor signal peptide. The oleD product showed clear similarity with several UDP-glucuronosyl- and UDP-glycosyl-transferases from different origins and particularly with the mgt gene from S. lividans, and might encode a glycosyltransferase activity capable of inactivating macrolides. It is proposed that these three genes could participate in the intracellular glycosylation of oleandomycin and its secretion during antibiotic production.     

Neuroleptic malignant syndrome in the acquired immunodeficiency syndrome

Patients infected by the human immunodeficiency virus are predisposed to many infectious and noninfectious complications and often receive a variety of drugs. Furthermore, they seem to have a particular susceptibility to idiosyncratic adverse drug reactions. It is therefore surprising that only a few cases of the neuroleptic malignant syndrome have been described in patients with the acquired immunodeficiency syndrome. A high index of suspicion is required to diagnose the neuroleptic malignant syndrome in these patients, as its usual manifestations, including fever and altered consciousness, are frequently attributed to an underlying infection.     

Reliability of coding of diagnoses recorded in the computerized information system at primary health care centers

OBJECTIVE: To find the reliability of the coding of diagnoses in the doctor's note in this computer system and to analyse where there are most discrepancies. DESIGN: An observational study. The concordance between the reason for consultation, codified by an external assessor, and the coding of the main diagnosis. SETTING: Health Districts 17 (Murcia/Barrio del Carmen) and 66 (Molina de Segura/La Ribera) in the Autonomous Community of Murcia. PATIENTS: A sub-sample of 228 consultations, belonging to a larger study of 1,904 general medical consultations (total: 98,768 consultations). MEASUREMENTS AND MAIN RESULTS: There were discrepancies between the coding of the reason for consultation and the diagnosis in 23% of the consultations recorded. The reason for consultation was not correctly recorded in 12.3%. The diagnostic group or section with the highest level of agreement was number XVIII or the supplementary section; and with the least agreement in XVII (injuries and adverse side-effects) and Number V covering mental disorders. CONCLUSIONS: Quality control of information and its validation enables errors and problems in the systems to be identified and corrected. This study points to the need to improve the filling-out of the reason for consultation and activity carried out, in order to obtain afterwards a more reliable coding of the diagnosis.     

Hygrothermal Aging Effects in Cured Epoxies

The effect of relatively severe hygrothermal aging on the sorption and also the diffusion of water at 40°C has been studied for a number of epoxy networks comprising tetraglycidyl 4,4′-diaminodiphenyl methane, and the curing agent 4,4′-diaminodiphenyl sulphone, 4,4′-diaminodiphenyl methane and 2,2′-dichloro-4,4′-diaminodiphenyl methane. Aging at high temperatures is accompanied by a pronounced increase in sorptive capacity at 40°C consistent with a significant expansion of the network. Dry annealing of the aged network at sub- T_g temperatures collapses the expanded structure to recover the sorptive capacity of the unaged network. Preliminary studies of the sorption-desorption kinetics for aged networks indicate that the effective diffusion coefficient is not markedly affected.     

Agglomerative clustering-based approach for two-dimensional phase unwrapping

We describe a novel algorithm for two-dimensional phase unwrapping. The technique combines the principles of agglomerative clustering and use of heuristics to construct a discontinuous quality-guided path. Unlike other quality-guided algorithms, which establish the path at the start of the unwrapping process, our technique constructs the path as the unwrapping process evolves. This makes the technique less prone to error propagation, although it presents higher execution times than other existing algorithms. The algorithm reacts satisfactorily to random noise and breaks in the phase distribution. A variation of the algorithm is also presented that considerably reduces the execution time without affecting the results significantly.     

Microbiology of a wetland ecosystem constructed to remediate mine drainage from a heavy metal mine

A pilot passive treatment plant (PPTP) was constructed to evaluate the potential of a composite wetland system to remediate acidic, metal-rich water draining the former Wheal Jane tin, in Cornwall, England. The treatment plant consists of three separate and controllable composite systems, each of which comprises a series of aerobic wetlands for iron oxidation and precipitation, a compost bioreactor for removing chalcophilic metals and to generate alkalinity, and rock filter ponds for removing soluble manganese and organic carbon. To understand the roles of microorganisms in remediating acid mine drainage (AMD) in constructed wetland ecosystems, populations of different groups of cultivatable acidophilic microbes in the various components of the Wheal Jane PPTP were enumerated over a 30-month period. Initially, moderately acidophilic iron-oxidising bacteria (related to Halothiobacillus neapolitanus) were found to be the major cultivatable microorganisms present in the untreated AMD, though later heterotrophic acidophiles emerged as the dominant group, on a numerical basis. Culturable microbes in the surface waters and sediments of the aerobic wetlands were similarly dominated by heterotrophic acidophiles, though both moderately and extremely acidophilic iron-oxidising bacteria were also present in significant numbers. The dominant microbial isolate in waters draining the anaerobic compost bioreactors was an iron- and sulfur-oxidising moderate acidophile that was closely related to Thiomonas intermedia. The acidophiles enumerated at the Wheal Jane PPTP accounted for 1% to 25% of the total microbial population. Phylogenetic analysis of 14 isolates from various components of the Wheal Jane PPTP showed that, whilst many of these bacteria were commonly encountered acidophiles, some of these had not been previously encountered in AMD and AMD-impacted environments.