Lancet 2000;355:2189–93 Because less than 1% of young women positive for oncogenic types of human papillomavirus (HPV) develop cancer, these investigators determined whether the amount of HPV DNA is a useful predictor of progression to cervical carcinoma in situ (CIS). Using a PCR technique to identify HPV DNA in 478 women with cervical carcinoma in situ and 608 matched controls, 3,835 archived cervical smears were studied, with multiple smears available for each woman. Some samples were 26 years old. Analysis of the first smear from each woman, collected a mean of 7–8 years before the CIS diagnosis, showed that women with the 20% highest amount of HPV 16 DNA were at a 60‐fold higher risk of developing CIS than women negative for HPV. The authors conclude that “the amount of HPV DNA can predict cancer risk when current screening methods are uninformative.” Comment: This study and a second one in the same issue of Lancet show that levels of HPV 16 DNA, and not just its presence or absence, confer a substantially increased risk of cervical cancer. Though way too expensive to use as a primary detection technique, this finding is certainly logical and parallels what is known about viral load and human immunodeficiency virus syndrome. (TMJ)

The RB method is a promising method for simultaneous noninvasive estimation of Qep and functional residual capacity in mechanically ventilated patients. However, further investigations are needed to evaluate potential problems of the method before it can be recommended for clinical purposes.

Some researchers (17, 18) have proposed the replacement of the liquid-concentrated phosphoric acid in gas-fed porous 02 consuming cathodes, with ionic conducting polymers such as Nation with the advantage of speeding up the kinetics of the oxygen reduction reaction by a mechanism similar to that proposed for the role of the PFSI addition. The use of additives such as PFSI has several advantages over the polymer including: (i) greater ease of access to the porous gas-fed electrode; (ii) self-healing in that the surface film, if disturbed, is automatically healed by the adsorption of the additive from the bulk solution; and (iii) it has essentially the same conductivity as concentrated phosphoric acid without the additive, in contrast to the polymer which, with its lower conductivity, gives rise to additional ohmic losses within the electrode.The vapor pressure of the PFSI itself is too high for operating under the practical fuel cell conditions (150~176 A condenser system could be used to recover the vaporized PFSI, but this would add substantial complications to the system. An alternative approach is to identify less volatile additives suitable for operating at higher temperatures. Work is in progress in our laboratory to substitute the PFSI by low volatile multifunctional perfluorosulfonimide, perfluorinated phosphonic, or phosphinic acids which could be used as additives in phosphoric acid at higher temperatures. ABSTRACTThe enhancement of limiting currents by inert suspended solids was studied using a rotating-disk electrode (RDE). The suspensions contained glass or polymer particles in various sizes (1-100 ~m) and concentrations (up to 40 v/o solids). Solid particles the same size as, or smaller than, the thickness of the mass-transfer boundary layer create small-scale "microconvective" vortices. Particles much larger than the boundary-layer thickness appear to enhance transport by a different mechanism, possibly involving the formation of particle-free wall layers. Disk-torque measurements show that substantial increases in the limiting current require significantly less stirring power using the suspensions than by increasing the rotation rate without solids.) unless CC License in place (see abstract). ecsdl.org/site/terms_use address. Redistribution subject to ECS terms of use (see 128.122.253.228 Downloaded on 2015-06-08 to IP ABSTRACT Calculations are performed for the purpose of determining the steady-state behavior of plated through-holes with various aspect ratios during the dc electrodeposition of copper over a wide range of operating conditions. The results indicate that when electrolyte flow is restricted the maximum average current density possible within the through-holes is much less than 1 mA/cm ~ and the current distribution is considerably nonuniform for the high aspect ratio through-holes.