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We assess the theoretical uncertainties on the inclusive J / ψ production cross section in the Color Evaporation Model (CEM) using values for the charm quark mass, renormalization and factorization scales obtained from a fit to the charm production data. We use our new results to provide improved baseline comparison calculations at RHIC and the LHC. We also study cold matter effects on J / ψ production at leading relative to next-to-leading order in the CEM within this approach.

We explore the available parameter space that gives reasonable fits to the total charm cross section to make a better estimate of its true uncertainty. We study the effect of the parameter choices on the energy dependence of the J/\psi\ cross section., Comment: 19 pages, 13 figures

A retrospective study of forty-one patients who had undergone subfascial ligation of perforating veins in the lower extremity, or Linton procedure, is presented. All procedures were performed by the same surgeon from 1971 to 1993. Two patients underwent bilateral procedures. There were 28 female patients and 13 males. Fifteen had a history of smoking. There was a history of previous thrombophlebitis in 21 patients, and 21 had a family history of varicosities and/or ulceration. Results of venograms and Doppler duplex studies, if done, were evaluated. Follow up procedures, such as sclerosing injections and skin grafts, were also noted. A total of 25 patients had subsequent sclerosing injections, one underwent debridement twice, and one received skin grafts, secondary to incisional skin necrosis. It was noted that there was no occurrence of wound infection or incisional necrosis when zinc oxide paste boots were applied and maintained post-operatively. All patients were contacted directly prior to the writing of this article to ascertain prevalence, severity, and circumstances of recurrence.

The problems encountered in acceptance testing of newly installed imaging equipment at two major medical institutions over a 10-year period are presented. Acceptance tests were conducted in 129 newly installed imaging systems with conventional acceptance testing methods. A total of 1,132 problems were documented. Problems were classified as major or minor; there were 772 major problems and 360 minor problems. An average of six major and three minor problems were documented in each new equipment installation tested. In some instances, final payment was withheld for several months or more to ensure correction of the problems identified. This experience confirms the need of thorough acceptance testing of new imaging equipment before final payment is made to the vendor.

An important aspect of the virological assessment of cell substrates used to produce biologicals is their retroviral status. In this presentation we will attempt to document some of the practical experiences of industry when testing cell substrates for retroviruses using infectivity tests, reverse transcriptase and electron microscopy. We will also explore some important aspects of the experimental design of these retrovirus assay systems and review some results from the application of these methods in model, experimental systems.

A new screening technique has been developed for the rapid identification of Neurospora crassa mutants that are deficient in nicotinamide adenine dinucleotide glycohydrolase (NADase) and nicotinamide adenine dinucleotide phosphate glycohydrolase (NADPase) activities. Using this procedure, five single-gene mutants were isolated whose singular difference from wild type appeared to be the absence of NAD(P)ase (EC 3.2.2.6). All five mutants were found to be genetically allelic and did not complement in heterocaryons. This gene, nada [NAD(P)ase], was localized in linkage group IV. One of the nada alleles was found to specify an enzyme that was critically temperature sensitive and had altered substrate affinity. Mutations at the nada locus did not affect the genetic program for the expression of NAD(P)ase during cell differentiation, nor did they have a general effect on NAD catabolism. Nada mutations did not have simultaneous effects on other glycohydrolase activities. Tests of dominance (in heterocaryons) and in vitro mixing experiments did not provide evidence that nada mutations alter activators or inhibitors of NAD(P)ase. Thus, the nada gene appears to specify only the structure of N. crassa NAD(P)ase.

In Lake Washington, fish production through detritus-based food chains is substantially greater than fish production through the grazing food chain. The lack of significant grazing by fish on the zooplankton is a consequence of both piscivore predation and conditions in the planktivore spawning environment. At low planktivore abundance, squawfish may switch to benthos feeding, exploiting the abundant prickly sculpin. At high planktivore abundance, squawfish feed more heavily on planktivores. Thus, even when reproductive success of planktivores is good, swamping of the squawfish population does not occur and depensatory mortality due to squawfish predation prevents planktivore abundance from increasing to the point where zooplankton resource depletion would occur. Benthic–littoral species are vulnerable to predation essentially only as larva and juveniles. They avoid predation by occupying littoral and epibenthic refugia. Recruitment to the adult population from these refugia may be sufficient to account for the greater rate of benthos exploitation by fish relative to the rate of zooplankton exploitation by fish. Neomysis is an important component of the Lake Washington fish production, since potentially Neomysis is a regulating agent on the zooplankton, and reduction in Neomysis predation on zooplankton, due to decreasing abundance and a deeper vertical distribution, may be partly responsible for the recent reappearance of Daphnia. The response of the fish community to trophic changes in Lake Washington has been slight. No consistent trends in the growth of fish utilizing zooplankton were observed. However, annual growth increments of consumers utilizing the benthic detrital food chain have declined with sewage diversion. The insights gained from analyzing the Lake Washington fish community structure and the Lake Washington carbon budget corroborate the above response of the fish community to trophic changes. Planktivores are predator-controlled and not able to deplete zooplankton resources, and thus would be insensitive to alterations in standing crop of zooplankton. On the other hand, benthic–littoral fish are more resource-limited and would be expected to respond to alterations in their forage base. Key words: ecosystem, fish, production, Lake Washington, eutrophication, predation

Development of upstream storage in the existing Columbia River basin made it economically attractive to add a second powerhouse to the existing Bonneville Project. The design problem concerned integrating the new powerhouse into a 40 year old project while meeting environmental constraints in river flow and providing for anadromous fish passage. Scope of treatment involves a general discussion of project ectrical and mechanical features with a review of equipment selected and reasons for selection in Certain cases. The resulting discussion provides information on the design of a large low head hydroelectric powerhouse which began commerical operation in 1981

Saturated standard cells at temperatures between 20°C and 40°C exhibit a high negative-voltage coefficient with respect to temperature and have required temperature stabilization within ±0.01°C over an extended period to achieve a voltage stability of ±1 ?V. Examination of standard cell data in the vicinity of 0°C, on the other hand, indicated higher voltages and a much lower temperature coefficient. In fact, the cell voltage reaches a maximum and consequently the voltage coefficient is zero at approximately 3°C, and is near zero over a range of several degrees. A cell maintenance temperature of 3°C, therefore, appears the most appropriate operating environment for a saturated cell in order to obtain maximum voltage stability. Heretofore, a convenient, high-stability, maintenance-free temperature bath operating near 3°C has not been available for laboratory use. The utilization of thermoelectricity to cool (Peltier effect) is currently available, and this method has been employed to provide a stable low-temperature ambient for saturated cells. This paper describes a practical air chamber-controller combination with thermoelectric heat pumping designed to test the behavior of saturated cells near 3°C. Details of the thermal and electrical characteristics of the unit will be discussed. Results show a ±0.2°C control is adequate to provide a primary voltage reference with ±1 ?V stability at 3.1°C. Advantages and precautions in maintaining cells at low temperatures will also be presented.

Tonalite (quartz diorite) in southern California has weathered under aa mediterranean climate to depths of more than 30 m. In weathering, the rock was broken up by expansion of biotite as it weathered to vermiculite. The particle density of the resulting fragments is the same as that of the rock (2.75 g/cm 3 ). Biotite comprises 14% of the rock and could produce a linear extensibility of 1.8% in such a uniform, medium-grained material if all the biotite weathered to vermiculite. Measured expansion (1–2%) of the fragmented rock agrees with the predicted value. Other minerals, mostly unweathered, in the rock are: andesine, 56%; hornblende, 13%; quartz, 9%; and orthoclase, 8%. Weathering of the fragmented rock to soil was studied in three kinds of environments in four closely associated soils of a toposequence. Differences in the weathering environments are a result of differences in topographic positions of the soils and resultant differences in soil moisture regimes. A slightly leached environment occurs on hilltop and backslope positions. These position are occupied by Ustochrepts and Haploxeralfs. B horizons of these soils have base saturations of less than 90%, lack salts in soil solution, and contain little exchangeable magnesium and sodium. In this environment vermiculite and kaolinite are formed from weathered biotite. No crystalline clay minerals were detected in the other primary minerals. A high sodium environment occurs in footslope positions. Natrixeralfs occupying these positions are slightly leached in upper parts but accumulate some soluble ions, especially sodium, magnesium, and in places carbonates and amorphous silica in lower parts. In this environment biotite weathers to vermiculite and kaolinite, andesine and hornblende to montmorillonite. The third environment is a base-rich environment found in areas of subdued relief and somewhat restricted drainage. The Pelloxererts in this position have significant amounts of soluble salts and large amounts of extractable magnesium and sodium. Minor amounts of secondary carbonates and amorphous silica accumulate below their sola. In the base-rich environment biotite weathers to vermiculite and montmorillonite, andesine and hornblende to a beidellite-montmorillonite. The beidellite-montmorillonite formed from the andesine is dioctahedral. Its structural formula is (Si 7.44 Al 0.56 )(Al 2.62 Mg 0.73 Fe 0.61 Ti 0.08 ) O 20 (OH) 4 (M + 0.95, K + 0.05 ) and it has a C.E.C. of 119 mequiv./100 g. The stability sequence for primary minerals from least to most stable is biotite, andesine, hornblende, quartz.

Through stereoscopic study of aerial photographs many features of the vegetation and also ground features can be directly identified. This has a practical application in mapping vegetation and soils in upland areas of California. This paper describes how vegetation types can be identified by analysis of the features visible on aerial photographs. It then describes how soil mapping is facilitated by photo interpretation of ground features, land form, and vegetation.

The technology of breeding uranium-233 from thorium-232 in a light water reactor is being developed and evaluated by the Westinghouse Bettis Atomic Power Laboratory (BAPL) through operation and examination of the Shippingport Light Water Breeder Reactor (LWBR). Bettis is determining the end-of-life (EOL) inventory of fissile uranium in the LWBR core by nondestructive assay of a statistical sample comprising approximately 500 EOL fuel rods. This determination is being made with an irradiated-fuel assay gauge based on neutron interrogation and detection of delayed neutrons from each rod. The EOL fissile inventory will be compared with the beginning-of-life fissile loading of the LWBR to determine the extent of breeding. In support of the BAPL proof-of-breeding (POB) effort, Argonne National Laboratory (ANL) carried out destructive physical, chemical, and radiometric analyses on 17 EOL LWBR fuel rods that were previously assayed with the nondestructive gauge. The ANL work included measurements on the intact rods; shearing of the rods into pre-designated contiguous segments; separate dissolution of each of the more than 150 segments; and analysis of the dissolver solutions to determine each segment's uranium content, uranium isotopic composition, and loading of selected fission products. This report describes the facilities in which this work was carried out, details operations involved in processing each rod, and presents a comprehensive discussion of uncertainties associated with each result of the ANL measurements.

Today, there is an ever increasing need for accessing the intestinal tract for feeding. I have devised a continent gastrostomy. This gastrostomy meets our criteria in that it is relatively easy to construct with a stapler, provides an excellent blood supply and is completely continent and resistant to breakdown. Feeding with gastrostomy is simple: a catheter is inserted at the beginning and removed at the completion of the feeding, yielding no evidence of reflux.