Few methods presently exist for routine benthic survey and sampling operations under permanent moving ice in high latitudes. Many benthic survey and sampling techniques commonly employed for blue-water oceanography are unsuitable for operations in ice covered seas due to the constrined maneuverability inherent in icebreaker operations. Over-theside deployments with lowered instruments prohibit ice-breaking and constrain the ship to the wind-driven motion of the ice. We propose that hybrid remotely operated vehicles (HROVs) with light data-only tethers could provide significantly enhanced under-ice scientific access to the world's high-latitude oceans. This paper identifies operational obstacles to benthic survey and sampling operations posed by permanent moving ice cover and proposes solutions to these obstacles.

Congenital indifference to pain (CIP) is a rare condition in which patients have severely impaired pain perception, but are otherwise essentially normal. We identified and collected DNA from individuals from nine families of seven different nationalities in which the affected individuals meet the diagnostic criteria for CIP. Using homozygosity mapping and haplotype sharing methods, we narrowed the CIP locus to chromosome 2q24–q31, a region known to contain a cluster of voltage‐gated sodium channel genes. From these prioritized candidate sodium channels, we identified 10 mutations in the SCN9A gene encoding the sodium channel protein Nav1.7. The mutations completely co‐segregated with the disease phenotype, and nine of these SCN9A mutations resulted in truncation and loss‐of‐function of the Nav1.7 channel. These genetic data further support the evidence that Nav1.7 plays an essential role in mediating pain in humans, and that SCN9A mutations identified in multiple different populations underlie CIP.

ABSTRACT The benefits shown by the recent introduction of PCR for the in vitro diagnosis of hepatitis C virus (HCV) infection has prompted the development of standardized, ready-to-use assays that can be implemented in routine clinical laboratories. We have evaluated the clinical performance of COBAS AMPLICOR HCV (COBAS), the first instrument system that allows the automation of HCV RNA amplification and detection, to determine its performance in the routine laboratory setting. More than 2,000 specimens collected at five centers were analyzed in parallel by the COBAS and the manual AMPLICOR HCV (AMPLICOR) tests, and the results were compared with the results for biochemical and serological markers of HCV. In this study the two PCR systems showed the same accuracy, with a concordance rate of 99.8%. As expected, the correlation between serology and PCR was not absolute because the presence of anti-HCV antibodies may be associated with a latent or past infection. On the other hand, if the presence of confirmed anti-HCV antibodies and elevated alanine aminotransferase levels are taken as the “gold standard,” indicating an active, ongoing infection, the COBAS and AMPLICOR tests show high and comparable sensitivities (100%) and specificities (98%), with positive and negative predictive values of 100 and 97%, respectively. During the study no false-positive reactions were detected. The use of an internal control allowed the identification of inhibitory substances that prevented amplification for 0.3 and 0.4% of samples tested by the COBAS and AMPLICOR tests, respectively. Compared to the manual system, the COBAS system allowed a significant reduction of hands-on time and could improve the overall laboratory work flow. In conclusion, these results support the use of the COBAS and AMPLICOR tests for the molecular diagnosis of active HCV infections.

EMSLAB (Electromagnetic Sounding of the Lithosphere and Beyond)—Juan de Fuca is the largest electromagnetic (EM) induction experiment ever carried out. The two general objectives are to investigate the electrical structure of the lithosphere and asthenosphere beneath a complete oceanic plate and the adjacent continent under which it is subducted and to study tidal, mesoscale eddy, and other large‐scale oceanic motions by measuring the electric currents induced in seawater as it moves in the geomagnetic field. More than 40 scientists, from 18 university and government institutions in the United States, Canada, Japan, Mexico, and Australia, are taking part.

Hadron-nucleus interactions have been studied in the 50 to 200 GeV/c momentum range for incident pions, kaons, protons, and antiprotons. Average charged multiplicities, dispersions of multiplicity distributions, absorption cross sections, and angular distributions are presented. The energy dependence of the target and projectile fragmentation regions is studied in detail.

Average multiplicities and pseudorapidity distributions for 100-GeV/c $p$-, ${K}^{+}$-, and ${\ensuremath{\pi}}^{+}$-nucleus collisions are presented. The average multiplicities increase with nuclear thickness. The fractional increase is independent of incident particle species, provided that nuclear thicknesses are calculated in units of mean free path of the incident hadron. This scaling behavior suggests that the immediate product of a hadron-nucleon collision is a state similar to the incident hadron.

We have performed a high-sensitivity search for massive long-lived particles produced at 2.5 mrad by 400-GeV/c protons on a beryllium target using time-of-flight, Cherenkov, and calorimetric techniques. A total of ${10}^{11}$ light particles (${\ensuremath{\pi}}^{\ensuremath{-}},{K}^{\ensuremath{-}},\overline{p}$) was sampled at 70 GeV/c. This experiment places a limit of 1.1\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}37}$ ${\mathrm{cm}}^{2}$/${(\mathrm{G}\mathrm{e}\mathrm{V}/\mathit{c})}^{2}$ \ifmmode\cdot\else\textperiodcentered\fi{} nucleon on the invariant cross section for the production of stable particles in the mass range of 4 to 10 ${\mathrm{G}\mathrm{e}\mathrm{V}/\mathit{c}}^{2}$.

Pseudorapidity distributions for proton-nucleus interactions are presented. The data cover twelve nuclei ranging from carbon to uranium and three incident proton momenta, 50, 100, and 200 GeV/c.Received 21 April 1977DOI:https://doi.org/10.1103/PhysRevLett.39.1499©1977 American Physical Society

The space-time evolution of particle production at high energies was investigated by measuring the charged multiplicity in ${\ensuremath{\pi}}^{\ensuremath{-}}$-nucleus collisions at 100 and 175 GeV/c. We find that (a) the forward multiplicity (in the $\ensuremath{\pi}p$ center-of-mass system) is independent of the target nucleus; (b) the backward multiplicity is approximately proportional to the nuclear thickness; and (c) the data are consistent with the assumption that the absorption cross section of the incident particle characterizes the multiplication process.