Prediction of VO\u3csub\u3e2\u3c/sub\u3e Peak Using Sub-Maximum Bench Step Test in Children

The purpose of this study was to develop a valid prediction of maximal oxygen uptake from data collected during a submaximum bench stepping test among children ages 8-12 years. Twentyseven active subjects (16 male and 11 female), weight 36.1 kg, height 144.4 cm and VO2 47.4 ± 7.9 ml/kg/min participated. Subjects completed a maximal oxygen consumption test with analysis of expired air and a submaximal bench stepping test. A formula to predict VO2max was developed from height, resting heart rate and heart rate response during the submaximum bench stepping test. This formula accounted for 71% of the variability in maximal oxygen consumption and is the first step in verifying the validity of the submaximum bench stepping test to predict VO2max. VO2max = -2.354 + (Height in cm * 0.065) + (Resting Heart Rate * 0.008) + (Step Test Average Heart Rate as a Percentage of Resting Heart Rate * -0.870

Space, the new frontier

Space program - high thrust boosters with greater payload capabilities, superior guidance and control, and astronaut trainin

Continuum Derrida Approach to Drift and Diffusivity in Random Media

By means of rather general arguments, based on an approach due to Derrida that makes use of samples of finite size, we analyse the effective diffusivity and drift tensors in certain types of random medium in which the motion of the particles is controlled by molecular diffusion and a local flow field with known statistical properties. The power of the Derrida method is that it uses the equilibrium probability distribution, that exists for each {\em finite} sample, to compute asymptotic behaviour at large times in the {\em infinite} medium. In certain cases, where this equilibrium situation is associated with a vanishing microcurrent, our results demonstrate the equality of the renormalization processes for the effective drift and diffusivity tensors. This establishes, for those cases, a Ward identity previously verified only to two-loop order in perturbation theory in certain models. The technique can be applied also to media in which the diffusivity exhibits spatial fluctuations. We derive a simple relationship between the effective diffusivity in this case and that for an associated gradient drift problem that provides an interesting constraint on previously conjectured results.Comment: 18 pages, Latex, DAMTP-96-8

Benchmark calculations for elastic fermion-dimer scattering

We present continuum and lattice calculations for elastic scattering between a fermion and a bound dimer in the shallow binding limit. For the continuum calculation we use the Skorniakov-Ter-Martirosian (STM) integral equation to determine the scattering length and effective range parameter to high precision. For the lattice calculation we use the finite-volume method of L\"uscher. We take into account topological finite-volume corrections to the dimer binding energy which depend on the momentum of the dimer. After subtracting these effects, we find from the lattice calculation kappa a_fd = 1.174(9) and kappa r_fd = -0.029(13). These results agree well with the continuum values kappa a_fd = 1.17907(1) and kappa r_fd = -0.0383(3) obtained from the STM equation. We discuss applications to cold atomic Fermi gases, deuteron-neutron scattering in the spin-quartet channel, and lattice calculations of scattering for nuclei and hadronic molecules at finite volume.Comment: 16 pages, 5 figure

The Occurrence of Trihalomethane Compounds in Salt Lake City and Ogden, Utah, Drinking Water Supplies

A purge and trap, gas chromatography system was developed to analyze for trihalomethane (THMs) compounds at the ppb (parts per billion) level in drinking water. Monthly influent and effluent samples were taken from three Weber Basin Water Conservancy Distrcit treatment plants, three Salt Lake City water treatmetn platns, and one Slat Lake Metropolitan water treatment plant. In addition tap water samples were taken at various business and residential locations in Salt Lake City, Utah, and Ogen, Utah. All samples were analyzed for trihalomethanes and total organic carbon (TOC). In addition to monthly sampling, a comparison of the production of THMs during post and prechlorination of water at the Parleys Water Treatment Plant in Salt Lake City was conducted. moving th epoint of chlorination within the treatment plant did not appear to reudce trihalomethane levels in the finished product. Highest trihalomethane levels (84 ug/1) occurred in the summer months with the lowest levels (\u3c1 ug/1) recorded in the winter. The chemical form of the THMs varied from chloroform to the more brominated hydrocarbon from late winter through spring

Removal of Nitrogen From Secondary Wastewater Effluent Through No 3-N Reduction Using Sulfur Dioxide (SO2)

The overall purpose of this study was to evaluate the ability of sulfur dioxide (SO2) to remove nitrate-nigrogen (i.e., reduction to a gaseous form) from the secondary wastewater effluent. To accomplish th above task, a jar test procedure was established and the concentration of NO3-N along with the concentration of NH3-N present in the secondary wastewater, treated with SO2, were measured initially and after 10 min, 20 min, 30 min, 40 min, and 24 hr. Then, the percent NO3-N removal was calculated, comparing the NO3-H concentrations measured in each treatment with the initial values. The above procedures were conducted for 36 different runs resulting from variation of the parameters which were believed to effect the kinetics of the reaction (i.e., SO2 concentration, presence of catalysts, temperature, and NO3-N concentration). Three levels of SO2 (500, 1000, 2000 mg/1), two levels of NO3-N(25-30 and 40-45 mg/1), two temperatures (20 degrees and 35 degrees Celsius), and two different catalysts (Fe+3 1 mg/1 and Feo 1 g/1) were used in this study. Prior to the jar tests, it was necessary to develop techniques to eliminate the SO2 interferences with analysis of NO2-N, and NH3-N. Two approahces were made to accomplish this task. First by air stripping of the SO2 treated secondary wastewater sample; secondly by diluting the SO2 treated secondary water to decrease the SO2 concentration to a level of less than 80 mg/1 as SO2. Satisfactory results were obtained applying both stripping and dilution methods

Direct Filtration Versus Conventional Water Treatment in the Intermountain Region

The direct filtration water treatment scheme does not include sedimentation and in some cases flocculation. Compared to conventional treatment, direct filtration has lowered capital costs, reduced space requirements, decreased sludge quantities, and reduced coagulant dosages. One objective of this research was the statistical comparison of the direct filtration, Utah Valley Water Purification Plant (Orem, Utah) and the conventional Little Cottonwood Water Treatment Plant (Salt Lake City, Utah). These treatment plants are the two most compatible treatment plants having the highest correlation of source water in the local area. The Little Cottonwood plant receives approximately 65 percent of its sources water from Deer Creek Reservoir whereas the Utah Valley plant receives all of its source water from Deer Creek Reservoir. Data from August 1, 1980, through August 31, 1983, were obtained from the daily water quality and plant operation logs of the two treatment plants. Utilizing the computer, the data were clocked into season means and compared staistically in several fashions. The water quality parameter of most importance in the comparison is the finished water turbidities. The most benficial results were obtained from a two-way analysis of variance using an F-ratio as the reference for signifiicance. The F-ratio for the finished water turbidity at the degree of significance, alpha = 0.01, proved not significant. The overall statistical analysis exhibits that the Utah Valley plant produces not only acceptable finished water turbinities well below EPA\u27s maximum contaminant level of 1 TU, but one that is also comparable in quality to that of the conventional processes of the Little Cottonwood Treatment Plant. Another objective of this research was the operation of two pilot-scale direct filtration systems at the Utah Valley treatment plant. The pilot plant treated the same source water and used the same dual-filter media as the Utah Valley treatment plant. The pilot plant flow processes consisted of a rapid mix basin, a flocculation basin, and the filter column. Filters were evaluated by the filter performance index (F.P.I.), which is based on the quantity of turbidity removed, the volume of water produced during a filter run, and effluent quality. The highest F.P.I. values were achieves during the filter runs using alum as the primary coagulant and a cationic polymer as a coagulant aid. These filter runs produced a product water with finished water rubidities considerably below the EPA maximum contaminant level of 1 TU. The most successful filter runs were characterized with filter loading rates ranging from 3 to 5 gpm/ft^2, and alum and polymer dosages ranging from 2.1 to 8.1 mg/l and 0.70 to 2.2 mg/l, respectively. These filter runs treated raw water with average turbidities from 13.6 to 22.8 NTU

Evaluation of Microcosms for Determining the Fate and Effect of Benz(a)anthracene in Aquatic Systems

Small scale, three-phase microcosms were used to study the aquatic fate and effect of a polycyclic aromatic hydrocarbon (PAH), benz(a)anthracene. This compound was chosen as a model for carcinogenic PAH because it is a typical constituent of petro-chemical effluents and has middle-of-the-range physical and chamical characteristics. In a series of experiments, techniques were established for monitoring the behavior and for assessing the biological response to the pollutant. Results indicate taht benz(a)anthracene has no acute effect on aquatic organisms as indicated by the parameters used to measure community structure and function (gas productivity, nutrient utilization, biomass accumulation, and species composition). Gas chromatograph/mass spectral analysis of benz(a)anthracene and metabolites in the medium sediment, and biota made it possible to trace the fate of the compound. At the end of one 60 day experiment, 76 percent remained in the sediment, 17 percent had been recovered in the medium, 1 percent was associated with the biota. Of the remaining 5 percent, a portion photodegraded. There was no evidence of metabolism

The field theoretic derivation of the contact value theorem in planar geometries and its modification by the Casimir effect

The contact value theorem for Coulomb gases in planar or film-like geometries is derived using a Hamiltonian field theoretic representation of the system. The case where the film is enclosed by a material of different dielectric constant to that of the film is shown to contain an additional Casimir-like term which is generated by fluctuations of the electric potential about its mean-field value.Comment: Link between Sine-Gordon and Coulomb gas pressures via subtraction of self interaction terms included. Discussion of results within Debye-Huckel approximation included. Added reference

Iron Dynamics in a Gas-Water-Sediment Microcosm

Iron dynamics in eutrophic systems were studied in the laboratory utilizing gas-water-Sediment phase sealed microcosms. Sediments from Hyrum Reservoir (2.4 percent iron by weight) were placed in the dark to simulate the hypolimnetic regions of a eutrophic impoundment. Iron both chemically and physically was readily available to microorganisms of the aqueous phase because iron in these systems was soluble. In the light microcosms, which simulated shallow littoral regions of eutrophic impoundments, iron was found in higher aqueous phase concentrations than was predicted chemically and physically; this was rationalized through biological mechanisms. The experiment was conducted in two phases: Phase I lasted 189 days (0 and 0.300 mg NO3–N/1 inputs) and phase II lated 175 days (10mg NO3-N/1 imput). Average light microcosm effluent iron concentrations increased from 0.092 mg FE/1 (Phase I) to 0.246 mg Fe/1 (Phase II) given higher inorganic nitrogen inputs. In Phase II, when nitrogen input into the microcosms ceased (nitrogen perturbations, day 115), aqueous phase iron concentrations in the dark microcosms increased dramatically (0.011 to 0.624 mg Fe/1)