Effects of information on the reinforcing, subjective, and psychomotor effects of nitrous oxide in healthy volunteers

One method of quality control which has recently been recommended by professional bodies in the UK is the 'rapid review' method. This involves the microscopic 30 s review of all negative cervical smears with the intention of flagging potential missed abnormalities. Although it has been suggested that rapid review is better than 10% random rescreening of negative smears, the efficiency and efficacy of this method of quality control have not been thoroughly evaluated. We have used the AxioHOME system, which can record the area of a slide covered and the screening time, to investigate slide coverage during rapid review quality control, as performed by 15 cytoscreeners and MLSOs reviewing a test set of 22 slides each. The test set comprised 18 negative slides, three positive slides, and one unsatisfactory slide. We have recorded two distinct methods of rapid review in use amongst cytotechnologists, the step method and the whole slide method. The data show that rapid review takes longer on average than the recommended 30 s, the mean screening times being 76 s and 82 s for the step and whole slide methods, respectively. Abnormal smears were missed on three of 15 occasions by the step method (sensitivity 80%, positive predictive value 85%), and on seven of 30 occasions by the whole slide method (sensitivity 76.6%, positive predictive value 45%). However, the 95% confidence intervals were wide (57.7-90.7% for the step method, and 51.9-95.7% for the whole slide method). Analysis of scanning tracks and screening rates shows significant flaws in the methodology of rapid review. Abnormal cells were not identified, although dyskaryotic cells were included in the scanning track on nine occasions, seven using the whole slide method and two using the step method. On one occasion (using the step method) abnormal cells were not identified because they were not included in the scanning track. Further research is in progress to determine optimal methods of rapid review, and whether the rapid review technique is as effective as automated screening systems for quality assurance in cytology.     

Retrospective comparison of infusional 5-fluorouracil, doxorubicin, and mitomycin-C (modified FAM) combination chemotherapy versus palliative therapy in treatment of advanced gastric cancer

About one-third of patients with gastric cancer are unresectable at the time of diagnosis. Their median survival is < 6 months, with a grave prognosis. The purpose of this study was to assess the efficacy of a modified FAM (mFAM) regimen in advanced gastric cancer. We retrospectively reviewed the clinical records of 409 advanced gastric cancer patients who had not received curative surgery. Among 409 patients, 202 patients were treated with an mFAM regimen (infusional 5-FU + doxorubocin + mitomycin-C), and 207 patients received no chemotherapy (control group). No differences were found in clinical parameters between the two groups. The 1-year survival rates were 34.1% for the mFAM-treated group and 22.5% for the control group (p = 0.0135). In subset analysis, a higher 1-year survival rate was demonstrated in patients with mFAM and palliative surgery. Of the 154 evaluable patients in the mFAM-treated group, the response rate was 17.5%. In these patients, median response duration was 30 weeks, and progression-free survival was 23 weeks. Overall toxicity of mFAM regimen was relatively tolerable and reversible. In conclusion, FAM combination chemotherapy, which has been used as a standard therapy, prolonged survival after modification of the administration schedule and combination with palliative surgery. A prospective randomized study is warranted to confirm this conclusion from our retrospective study.     

Numerical accuracy of multipole expansion for 2D MLFMA

A numerical study of the multipole expansion for the multilevel fast multipole algorithm (MLFMA) is presented. In the numerical implementation of MLFMA, the error comes from three sources: the truncation of the addition theorem; the approximation of the integration; the aggregation and disaggregation process. These errors are due to the factorization of the Green's function which is the mathematical core of the algorithm. Among the three error sources, we focus on the truncation error and a new approach of selecting truncation numbers for the addition theorem is proposed. Using this approach, the error prediction and control can be improved for the small buffer sizes and high accuracy requirements.     

RELATIONSHIPS BETWEEN CONSTANTS OF THE FREUNDLICH EQUATION AND TEMPERATURE FOR GASEOUS ADSORPTION

For the Freundlich equation, the linear dependences of In k and n on T and In k on n were derived theoretically and examined by experimental data. In addition, the influence of the adsorbed amount on the isosteric heat of adsorption was also studied. The result shows that the isosteric heat of adsorption is varied linearly with the logarithm of adsorbed amount, ft is also found from experimental data that the plots of In k vs. n for various adsorbates adsorbed on the same adsorbent can be correlated by a straight line for adsorbates with the similar values of the parameter A' of Clapeyron equation.     

Over-erase phenomenon in SONOS-type flash memory and its minimization using a hafnium oxide charge storage Layer

The over-erase phenomenon in the polysilicon-oxide-silicon nitride-oxide-silicon (SONOS) memory structure is minimized by using hafnium oxide or hafnium aluminum oxide to replace silicon nitride as the charge storage layer (the resulting structures are termed SOHOS devices, where the "H" denotes the high dielectric constant material instead of silicon nitride). Unlike SONOS devices, SOHOS structures show a reduced over-erase phenomenon and self-limiting charge storage behavior under both erase and program operations. These are attributed to the differences in band offset and the crystallinity of the charge storage layer.     

Expression of expansin genes is correlated with growth in deepwater rice

Expansins are a family of proteins that catalyze long-term extension of isolated cell walls. Previously, two expansin proteins have been isolated from internodes of deepwater rice, and three rice expansin genes, Os-EXP1, Os-EXP2, and Os-EXP3, have been identified. We report here on the identification of a fourth rice expansin gene, Os-EXP4, and on the expression pattern of the rice expansin gene family in deepwater rice. Rice expansin genes show organ-specific differential expression in the coleoptile, root, leaf, and internode. In these organs, there is increased expression of Os-EXP1, Os-EXP3, and Os-EXP4 in developmental regions where elongation occurs. This pattern of gene expression is also correlated with acid-induced in vitro cell wall extensibility. Submergence and treatment with gibberellin, both of which promote rapid internodal elongation, induced accumulation of Os-EXP4 mRNA before the rate of growth started to increase. Our results indicate that the expression of expansin genes in deepwater rice is differentially regulated by developmental, hormonal, and environmental signals and is correlated with cell elongation.     

Mismatch repair by efficient nick-directed, and less efficient mismatch-specific, mechanisms in homologous recombination intermediates in Chinese hamster ovary cells

Repair of single-base mismatches formed in recombination intermediates in vivo was investigated in Chinese hamster ovary cells. Extrachromosomal recombination was stimulated by double-strand breaks (DSBs) introduced into regions of shared homology in pairs of plasmid substrates heteroallelic at 11 phenotypically silent mutations. Recombination was expected to occur primarily by single-strand annealing, yielding predicted heteroduplex DNA (hDNA) regions with three to nine mismatches. Product spectra were consistent with hDNA only occurring between DSBs. Nicks were predicted on opposite strands flanking hDNA at positions corresponding to original DSB sites. Most products had continuous marker patterns, and observed conversion gradients closely matched predicted gradients for repair initiated at nicks, consistent with an efficient nick-directed, excision-based mismatch repair system. Discontinuous patterns, seen in approximately 10% of products, and deviations from predicted gradients provided evidence for less efficient mismatch-specific repair, including G-A-->G-C specific repair that may reflect processing by a homologue of Escherichia coli MutY. Mismatch repair was > 80% efficient, which is higher than seen previously with covalently closed, artificial hDNA substrates. Products were found in which all mismatches were repaired in a single tract initiated from one or the other nick. We also observed products resulting from two tracts of intermediate length initiated from two nicks.     

Pharmaceutical rejection by membranes for wastewater reclamation and reuse.

Various membranes, which have different materials and nominal molecular weight cut-offs (MWCO), were compared in terms of rejection of ibuprofen and removal of effluent organic matter (EfOM) from membrane bioreactor (MBR), because pharmaceutical compounds contain a potential risk and EfOM is the precursor of carcinogenic disinfection by-products when reusing for drinking water source. To provide equivalent comparison with respect to hydrodynamic condition, mass transfer parameter, J0/k ratio, was used. A tight-UF membrane with a molecular weight cut off of 8,000 daltons exhibited 25 approximately 95% removal efficiencies of ibuprofen with a molecular weight of 206 with and without presence of EfOM(MBR). EfOM(MBR) caused the reduction of ibuprofen removal efficiency for UF membrane. Rejection of EfOM(MBR) by UF and NF membranes ranged 29 approximately 47% and 69 approximately 86%, respectively. UF membrane could successfully remove ibuprofen at lower J0/k ratio range (< or = 1) in organic free water but could not efficiently reject ibuprofen with a relatively hydrophilic EfOM(MBR) (SUVA < or = 3).     

A /spl Sigma/-/spl Delta/ fractional-N frequency synthesizer using a wide-band integrated VCO and a fast AFC technique for GSM/GPRS/WCDMA applications

A fractional-N frequency synthesizer (FNFS) in a 0.5-/spl mu/m SiGe BiCMOS technology is implemented. In order to operate in a wide-band frequency range, a switched-capacitors bank LC tank voltage-controlled oscillator (VCO) and an adaptive frequency calibration (AFC) technique are used. The measured VCO tuning range is as wide as 600 MHz (40%) from 1.15 to 1.75 GHz with a tuning sensitivity from 5.2 to 17.5 MHz/V. A 3-bit fourth-order /spl Sigma/-/spl Delta/ modulator is used to reduce out-of-band phase noise and to meet a frequency resolution of less than 3 Hz as well as agile switching time. The experimental results show -80 dBc/Hz in-band phase noise within the loop bandwidth of 25 kHz and -129 dBc/Hz out-of-band phase noise at 400-kHz offset frequency. The fractional spurious is less than -70 dBc/Hz at 300-kHz offset frequency and the reference spur is -75 dBc/Hz. The lock time is less than 150 /spl mu/s. The proposed synthesizer consumes 19.5 mA from a single 2.8-V supply voltage and meets the requirements of GSM/GPRS/WCDMA applications.