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The ability to detect and accurately pinpoint areas of existing and/or early-stage convection is critical to improving situational awareness and safety in the aviation industry. Given thunderstorms by definition include lightning and the vast majority of lightning is typically in-cloud (IC) as opposed to cloud-to ground (CG), it is necessary to have a network in place that detects total lightning activity (i.e., both IC and CG). Total lightning has been demonstrated to correlate well with storm dynamics and both case studies and statistical analyses suggest that total lightning is related to the presence or high likelihood of flight hazards such as hail, icing and turbulence. Additionally, lightning itself also poses a direct safety hazard to airborne aircraft as lightning strikes can cause engine failure, disrupt and damage aircraft electrical systems, lead to smoke and on-board fires, and temporarily affect flight crew vision. Total lightning information is also an important complement to existing weather radars as it can be highly useful in identifying areas of convection beyond radar ranges, locations where radar beams are blocked (i.e., mountainous areas), as well as early stage convective regions where precipitation returns do not yet appear significant. Given that CG activity typically represents a small fraction of the lightning occurring in the atmosphere, CG detection networks are not sufficient to meet the mission requirements of organizations tasked with providing critical information to aviation interests. The emergence of total lightning availability offers significant opportunities to enhance aviation flight safety. To this end the National Transportation Safety Board (NTSB) published a safety recommendation stating that the Federal Aviation Administration should consider several enhancements to its operations including; incorporation of total lightning data into weather displays at both air route traffic control centers and terminal radar approach control facilities, as well as into products supplied to pilots in the cockpit [17]. This paper reviews available total lightning network technology and potential applications for enhancing aviation safety. Case studies are reviewed and derivative products, such as proxy radar estimates, VIL and eco-tops are described.

The penetration depth λ in the filled-skutterudite heavy-fermion superconductor PrOs4Sb12 has been measured using transverse-field muon spin rotation (TF- μ SR ). It is found to be temperature-independent at low temperatures, consistent with a nonzero gap for quasiparticle excitations. In contrast, radiofrequency (RF) measurements yield a stronger temperature dependence of λ ( T ) , indicative of point nodes in the gap. A ∼ 10 % discrepancy is found at low temperatures. This may be due to mechanisms that modify the vortex-state field distribution, or to the surface scattering which breaks pairs in an odd-parity superconductor. Alternatively, it may be a matter of field orientation of nodal gap structure in the μ SR measurements.

We present the first μ SR measurements ever performed on elemental Pu, and set the most stringent upper limits to date on the magnitude of the ordered moment μ ord in α -Pu and δ -stabilized Pu (alloyed with 4.3 at% Ga). Assuming a nominal hyperfine coupling field of 1 kOe/ μ B we find μ ord ⩽ 10 - 3 μ B at T ≅ 4 K .

We present transverse-field (TF) measurements of the in-plane magnetic-field penetration depth λ ( T ) in single-crystalline PuCoGa 5 ( T c = 18.5 K ) for 0.06 T applied field ( ≈ 2 – 5 × H c 1 ) . We find that the temperature dependence of the superfluid density, and therefore Δ λ ( T ) = λ ( T ) - λ ( 0 ) , is ∝ T for T / T c ⩽ 0.5 . We estimate that the measured λ ( 0 ) = 241 ( 3 ) nm . ZF measurements find no evidence for time-reversal symmetry violation. The ZF and TF measurements are consistent with an even-parity (pseudo-spin singlet), d-wave pairing state.

In recent years, exploration of the Lower Congo Basin in Angola has focused on the Neogene turbidite sand play of the Malembo Formation. Gravity tectonics has played an important role during deposition of the Malembo Formation and has imparted a well-documented structural style to the post-rift sediments. An oceanward transition from thin-skinned extension through mobile salt and eventually to thin-skinned compressional structures characterises the post-rift sediments. There has been little discussion, however, regarding the influence of these structures on the deposition of the Malembo Formation turbidite sands. Block 4 lies at the southern margin of the Lower Congo Basin and is dominated by the thin-skinned extensional structural style. Using a multidisciplinary approach we trace the post-rift structural and stratigraphic evolution of this block to study the structural controls on Neogene turbidite sand deposition. In the Lower Congo Basin the transition from terrestrial rift basin to fully marine passive margin is recorded by late Aptian evaporites of the Loeme Formation. Extension of the overlying post-rift sequences has occurred where the Loeme Formation has been utilised as a detachment surface for extensional faults. Since the late Cretaceous, the passive margin sediments have moved down-slope on the Loeme detachment. This history of gravity-driven extension is recorded in the post-rift sediments of Block 4. Extension commenced in the Albian in the east of the block and migrated westwards with time. In the west, the extension occurred mainly in the Miocene and generated allochthonous fault blocks or “rafts”, separated by deep grabens. The Miocene extension occurred in two main phases with contrasting slip vectors; in the early Miocene the extension vector was to the west, switching to southwest-directed extension in the late Miocene. Early Miocene faults and half-grabens trend north–south whereas late Miocene structures trend northwest–southeast. The contrast in slip vectors between these two phases emphasises the differences in driving mechanisms: the early Miocene faulting was driven by basinward tilting of the passive margin, but gravity loading due to sedimentary progradation is considered the main driver for the late Miocene extension. The geological evolution of the late Miocene grabens is consistent with southwest-directed extension due to southwest progradation of the Congo fan. High-resolution biostratigraphic data identifies the turbidite sands in Block 4 as early Miocene (17.5–15.5 Ma) and late Miocene (10.5–5.5 Ma) in age. Deposition of these sands occurred during the two main phases of gravity-driven extension. Conditions of low sedimentation rates relative to high fault displacement rates were prevalent in the early Miocene. Seafloor depressions were generated in the hangingwalls of the main extensional faults, ultimately leading to capture of the turbidity currents. Lower Miocene turbidite sand bodies therefore trend north–south, parallel to the active faults. Cross-faults and relay ramps created local topographic highs capable of deflecting turbidite flows within the half grabens. Flow-stripping of turbidity currents across these features caused preferential deposition of sands across, and adjacent to, the highs. Turbidite sands deposited in the early part of the late Miocene were influenced by both the old north–south fault trends and by the new northwest–southeast fault trends. By latest Miocene times turbidite channels crosscut the active northwest–southeast-trending faults. These latest Miocene faults had limited potential to capture turbidity currents because the associated hangingwall grabens were rapidly filled as pro-delta sediments of the Congo fan prograded across the area from the northeast.

Since mdx limb muscle regeneration in vivo is accompanied by rapid myoblast proliferation and differentiation compared to normal, we tested the possibility that proliferation and differentiation were differentially regulated in normal and mdx dystrophic muscle cells. Cell cycle behavior, MyoD expression, and the effects of thyroid hormone (T3) treatment were examined in primary cultures. Using a 4-hour pulse time for bromodeoxyuridine (BrdU) incorporation during S-phase, the phases of the cell cycle (early S, late S, G(2)/M, and G(0)/G(1)) were separated by 2-colour fluorescence (BrdU/PI) analysis using flow cytometry. The G(0)/G(1)-early S and the late S-G(2)/M transitions were examined under the influence of T3 in cycling normal and mdx muscle cell cultures over a 20-hour time period. Myogenesis and differentiation were assessed morphologically and by immunostaining for MyoD protein. Mdx cultures had fewer cells in G(0)/G(1) at 20 hours and more cells in early and late S-phase compared to normal cultures. T3 significantly increased the proportion of normal cells in early S-phase by 20 hours, and reduced the proportions in G(2)/M phase. Over the same time interval in parallel cultures, the proportion of MyoD+ normal cells decreased significantly. In the absence of T3, mdx cell cultures showed greater proportions of cells in S-phase than normal cultures, and similar increases in S-phase and loss of MyoD expression over time. However, mdx cultures had no change in the proportion that were MyoD+ during T3 treatment. The results confirm that T3 in primary cultures increased proliferation and prevented the de-differentiation of mdx cells to a greater degree than was typical of normal cells. The different susceptibilities to T3-related shifts between proliferation and differentiation observed in vitro support the idea that committed mdx myoblasts may be more activated and proliferative than normal myoblasts during regeneration in vivo.

We measured the analyzing power and the efficiency of a new neutron polarimeter that was designed to measure G/sub E//sup n/, the neutron electric form factor. The polarimeter calibration was performed as experiment E377 at the Indiana University Cyclotron Facility (IUCF) with the /sup 14/C(p/spl I.oarr/,n/spl I.oarr/)/sup 14/N reaction at proton beam energies of 124.0, 164.6, and 199.7 MeV without any shielding material ahead of the polarimeter; in addition, at 164.6 MeV we measured the analyzing power with 10 cm of lead, sandwiched between 3.5-cm iron plates, ahead of the polarimeter.

Longitudinal-field muon spin relaxation (LF- μ SR) experiments have been performed in unannealed and annealed samples of the heavy-fermion compound UCu 4 Pd to study the effect of disorder on non-Fermi liquid behavior in this material. The muon spin relaxation functions G ( t , H ) obey the time-field scaling relation G ( t , H ) = G ( t / H γ ) previously observed in this compound. The observed scaling exponent γ = 0.3 ± 0.1 , independent of annealing. Fits of the stretched- exponential relaxation function G ( t ) = exp [ - ( Λ t ) K ] to the data yielded stretching exponentials K 1 for all samples. Annealed samples exhibited a reduction of the relaxation rate at low temperatures, indicating that annealing shifts fluctuation noise power to higher frequencies. There was no tendency of the inhomogeneous spread in rates to decrease with annealing, which modifies but does not eliminate the glassy spin dynamics reported previously in this compound. The correlation with residual resistivity previously observed for a number of NFL heavy-electron materials is also found in the present work.

The electron transfer properties of the complex, ReO(ECD), where H 2 ECD is N , N ′-1,2-ethylenediylbis- L -cysteine, diethyl ester, are reported. The results of this study will demonstrate that ReO(ECD) has an unusual reductive electron transfer mechanism, in that the addition of one electron to this complex results in the loss of H /sd from the ligand. This corresponds to the net loss of a proton (H + ) from the complex and hence the product of the reduction is the same as that obtained by the reaction of a base with ReO(ECD) to form [ReO(ECD)] − .

Approximately half of HIV-discordant heterosexual couples in the United States want children. Oral antiretroviral preexposure prophylaxis, if effective in reducing heterosexual HIV transmission, might be an option for discordant couples wanting to conceive. Couples should receive services to ensure they enter pregnancy in optimal health and receive education about all conception methods that reduce the risk of HIV transmission. In considering whether preexposure prophylaxis is indicated, the question is whether it contributes to lowering risk in couples who have decided to conceive despite known risks. If preexposure prophylaxis is used, precautions similar to those in the current heterosexual preexposure prophylaxis trials would be recommended, and the unknown risks of preexposure prophylaxis used during conception and early fetal development should be considered. Anecdotal reports suggest that oral preexposure prophylaxis use is already occurring. It is time to have open discussions of when and how preexposure prophylaxis might be indicated for HIV-discordant couples attempting conception.

Triple-track and interdigitated comb patterns used in testing of encapsulated microelectronic circuits are considered. The tests involved high-resistance DC measurements; e.g. applying 10-200-V DC and measuring currents in the 0.1-10-pA range. At these resistance levels, shunt impedances, arising from a variety of sources, have an impact on results. Without careful experimental design, one encounters artifacts that have nothing to do with the circuit/specimen under test. The authors detail proper experimental design, together with practical tests for artifacts. Both bulk- and interphase-resistance measurements are discussed. >

Sixty-four crossbred heifers, individually penned and fed, were used in a growing trial to evaluate four levels of wet brewers grain (WBG). A randomized block design was used to evaluate diet dry matter at four levels: 1} 0%, 2} 3%, 3} 12%, and 4} 33% WBG. The remainder of the diet included cornsilage and supplements. Feeding 33% WBG reduced (P

Sixty-four mixed breed steers were blocked on weight, randomly assigned to four treatments, and placed in individual pens. Treatments included finishing diets containing on a dry matter basis: 1) 8% corn silage (CS), 2) 8% wet brewers grain (WBG),3) 16% WBG, and 4) 24% WBG. Feed intake washigher (P

The title compounds have temperature-dependent n.m.r. spectra from which rotational barriers for iso -propyl and tert -butyl groups can be determined. Molecular mechanics calculations are used to indicate the conformations involved in these rotations and other stable conformations, and the possible pathways for their interconversions.

Background It remains unclear which donor and recipient factors influence long-term allograft function in lung transplantation (LTx). Methods From October 1988 to February 2005, a total of 280 recipients underwent LTx at our center. Donor data and cause of death (CoD) were analyzed. The CoD was categorized according to rate of increase in intracranial pressure at the time of death. Each donor and recipient factor was correlated with long-term graft function. Recipient details, type of transplant, indication for transplant, and time on waiting list were analyzed. Recipients were stratified based on allograft ischemia time (AIT): 0 to 6, 6 to 8, 8 to 10, and >10 hours. Results Mean donor age was 30.9 years (36.7% male); 49.8% were cytomegalovirus (CMV) positive. Donor CoD was characterized by a slow rise in intracranial pressure (ICP) in 34.4%, rapid ICP in 18.7%, an intermediate ICP in 44.3%, and with no rise in 2.6%. A graft survival benefit was seen with female donors (P = .048); 34.4% of recipients ultimately developed graft failure at long term follow-up. Mean recipient age was 48 years; 63% were male and mean body-mass index (BMI) was 23.6; 60.2% had single lung transplantation, and mean wait list time was 323 days. Mean AIT totaled 421 minutes. Graft survival was longer with AIT of 8 to 10 hours compared to 6 to 8 hours (P = .03). Conclusions Donor factor analysis implied only female donor status conferred a long-term graft survival advantage. Intracranial pressure rise differences appear clinically unimportant. Prolonged cold ischemic time (>10 hours) or low recipient BMI did not adversely affect allograft function in our review.

Longitudinal-field muon spin relaxation experiments have been carried out in the paramagnetic state of single-crystal Gd_2Ti_2O_7 just above the phase transition at T_m = 1.0 K. At high applied fields the exponential relaxation time T_1 is proportional to field, whereas T_1 saturates below a crossover field B_c that is ~2.5 T at 1.5 K and decreases as T_m is approached. At low fields the relaxation rate increases markedly as the freezing temperature is approached, as expected for critical slowing down of the spin fluctuations, but the increase is suppressed by applied field. This behavior is consistent with the very long autocorrelation function cutoff time implied by the low value of B_c., 4 pages, 2 figures, submitted to 10th International Conference on Muon Spin Rotation, Relaxation, and Resonance, Oxford, UK, August 2005

The budgeting process of an organization establishes a standard for the number and type by job code of positions available for hire. As applicants become employees the position becomes completely or partially filled. As employees transfer in and out, or terminate, the position in turn becomes unfilled or filled again. One of the responsibilities of a manager is to keep payroll expenses within the parameters of the budget. Hiring more than the budgeted number of positions will exceed the parameter. Hiring less than the budgeted number of positions may compromise the level of care and may lead to increased stress and burnout of the staff. A method utilized to provide the manager with timely information regarding the status of the budgeted positions for a specific department is a computerized position requisition system.

Allogeneic bone marrow transplantation (BMT) is the only treatment modality that has consistently been demonstrated to cure patients with the myelodysplastic syndrome (MDS). Since the early 1980s, numerous publications have reported the results with BMT for over 700 patients with MDS and the lead patients are now disease-free for more than 16 years. Overall, these studies show that approximately 40% of patients are likely to be cured with allogeneic BMT. The best results have been reported for patients with refractory anemia who receive marrow from fully matched related donors, with 75% long-term disease-free survival rates. Factors that are associated with an increased risk of relapse and, thereby, shorter disease-free survival, include increased blast percentage and poor risk karyotype. Factors that are associated with an increased risk of non-relapse mortality and, in some studies, shorter disease-free survival, include longer disease duration, advanced patient age, therapy-related MDS, male patients, and use of mismatched or unrelated donors. However, favorable results have been seen in small studies of patients 55-66 years of age and in patients with refractory anemia undergoing matched unrelated donor BMT. Allogeneic BMT is appropriate therapy for patients with high or intermediate risk disease (risk category based on the International Prognostic Scoring System). The use of allogeneic BMT for patients with low risk disease is not well defined, but may be appropriate for particularly young individuals or those with a life-threatening single cytopenia.

Testosterone reversed the age-related increase in glial fibrillary acidic protein (GFAP) in the male rat cerebellum, a brain region not generally associated with gonadal steroid hormone sensitivity. This supports the hypothesis that a decrease in circulating testosterone contributes to age-related increase in GFAP. These data also suggest that reductions in circulating gonadal steroids during aging could render the brain more susceptible to neurodegeneration and that hormone replacement therapy might have value in neurodegenerative disease intervention.

Zero-field muon spin relaxation (μSR)(μSR) in non-Fermi liquid Ce0.2La0.8RhIn5 reveals disordered spin freezing with a sharp transition at 0.16 K. The frozen moment at T=0T=0 is estimated as ∼0.13μB/Ce, an order of magnitude smaller than found from thermodynamic data at higher fields and temperatures. Longitudinal-field μSRμSR exhibits no dynamic relaxation at any temperature, showing that the spin freezing is not accompanied by the slow spin fluctuations found in spin glasses above the glass temperature and in other disordered non-Fermi liquid systems.

During FY 1994, three multiport wells were installed in Waste Area Grouping (WAG) 5. The wells were instrumented with Westbay multiport systems. The purpose of the wells is (1) to characterize different flow systems and (2) to monitor for contaminants. The geology of the individual boreholes (WAG 5-12, WAG 5-13, WAG 5-14) is documented in Bechtel National, Inc., (BNI) et al. (1994). The Bechtel report does not explicitly show geologic relationships between these boreholes or integrate this information into the geology of WAG 5. The purpose of this report is to document and present a summary of the distribution of geologic formations in WAG 5. This information is presented in several ways: (1) stratigraphic correlation diagrams based on the natural gamma ray log, (2) geologic cross sections, and (3) a geologic map. This work provides a reference frame for interpreting flow, water, and contaminant chemistry data from multiport wells.

On-line measurement of refining development is of vital concern to the papermaker since its control directly affects the uniformity of the product, drainage, drying and energy consumption. The current methods of monitoring fiber development during refining rely on secondary measures such as: Drainage rate, either measured off-line as Canadian standard freeness, or on-line with a number of commercial sample and test devices; energy consumption at the refiner; or changes in vacuum on the paper machine. To overcome these limitations of the existing technology, this project was designed to evaluate the use of a new type of sensor to monitor fiber development during refining. This sensor, a Lasentec Scanning Laser Microscope (SLM), is currently used as a particle size analyzer for slurries. The sensor will be described in more detail later. The use of this sensor had been successful in the laboratory. This project, was to establish this instrument as an in-line means to directly monitor refining.

The objective of this study was to compare the tibial structure and the strength of the tibia during muscle weakness and after recovery in mdx mice (which demonstrate X-linked muscular dystrophy and subsequent muscle regeneration) and age-matched control mice. The extent of disuse atrophy produced by muscle weakness and recovery following restoration of normal muscle strength could then be determined. The tibiae adjacent to weakened tibialis anterior muscles of 4-week-old mdx mice had significantly reduced radiographic density (p < 0.05) and cortical thickness (p < 0.001), and increased porosity (p < 0.001) compared to age-matched controls, suggesting development of disuse osteopenia. Significantly less force was required to break mdx tibiae than age-matched control tibiae (p < 0.05). In addition, Sharpey's fiber density was reduced (p < 0.001), suggesting a weakened attachment of the tibialis anterior muscle to bone. At 12 weeks, during the period of muscle regeneration, mdx tibial cortical thickness (p < 0.001) and porosity (p < 0.01) remained significantly lower, but percent calcium and Sharpey's fiber and radiographic densities were significantly greater (p < 0.001) than in age-matched controls, suggesting that bone mineralization and muscle attachment strength had increased to above normal levels in parallel with recovery of strength by the attached muscle. By 18 weeks, mdx tibial cross-sectional area, cortical thickness, and porosity remained significantly less (p < 0.001) than normal. Although Sharpey's fiber density was greater than in age-matched controls (p < 0.001) by 18 weeks, mdx tibial percent calcium (p < 0.005) and Sharpey's fiber density (p < 0.001) were significantly reduced from levels in 12-week-old mdx animals. There was significantly less deformation of the tibia prior to fracture in mdx than control tibiae at 18 weeks of age, suggesting tibial brittleness. Thus, at the site of attachment of mdx muscle to osteopenic bone, the remodelling which accompanies recovery of muscle strength is atypical, and produces an attachment of greater strength than function appears to require. These observations suggest that data are needed regarding bone mass and muscle-bone attachments in humans with disuse osteopenia, DMD, and other neuromuscular diseases.

The PAR-TEC 100, a particle size analyzer manufactured by Lasentec, Inc., is being evaluated as a sensor for in-line monitoring of fiber development during refining. The approach used is to beat softwood pulp in a Valley beater to produce a three point beater curve and to compare PAR-TEC measurements on those samples with Canadian Standard Freeness, Kajaani fiber length and coarseness, as well as tensile, wet tensile and tear strength. There is a very good positive correlation between PAR-TEC 100 scan counts mean size and tensile index; and a strong negative correlation to Canadian standard freeness, and Kajaani fiber length when evaluating Valley beater fiber development. There is a positive relation between the results of analyzing the individual Bauer-McNett fiber fractions with both the Kajaani 100 and PAR-TEC 100. These results indicate that the PAR-TEC 100 measures a complex value of fiber size, which under the correct circumstances is directly related to Kajaani arithmetic average fiber length. 16 figs.

Field and bench-scale reverse osmosis experiments on wastewater derived from automotive electrocoat paint operations are reported. Field experiments were performed continuously over a six-month interval using a reverse osmosis unit equipped with cellulose acetate membranes. An operating pressure of 3100 kPa (450 psi) and a temperature of 24–27°C was maintained. These RO experiments were unusual for two reasons. First, certain solutes in the feedwater were allowed to permeate through the membrane along with water. This was done to permit solute recycling and reuse. Since these solutes (ethyl, butyl and hexyl glycol ethers) were present in a 3% total concentration in the feedstream, their permeation through the membrane eliminated a flux reduction mechanism. This would arise from the increased upstream osmotic pressure if these solutes were concentrated. Second, the experiments were performed under conditions where colloidal lead was present. This caused limited membrane fouling which was controlled via weekly cleaning with dilute lactic acid. Some supporting bench-scale RO experiments were carried out to probe factors influencing this RO application.

Bench-scale reverse osmosis measurements have been performed on aqueous solutions of phenol, p-nitrophenol, aniline, coumarin, sodium lauryl sulfate and sodium naphtalene sulfonate. Asymmetric cellulose acetate membranes were used. Low concentrations of dissolved organics produce modest reversible reductions of permeate flux. Higher concentrations of aniline dissolve the membrane, while high phenol concentrations effectively plasticize the membrane removing its asymmetric structure. Electron micrographs of plasticized and unplasticized membranes are shown.

Allele frequencies of Yta (YT1) and Ytb (YT2) in a series of 659 random Canadian Caucasians are comparable to those in European populations: 0.9469 and 0.0531, respectively. Inheritance of Yt phenotypes in 1,077 children in 286 selected families are in accordance with expectation on the basis of Mendelian codominance. Linkage studies exclude YT from chromosomal segments 1p36-1p22.1, 4q13-4q28, the section of chromosome 9 bounded by AB0 and AK1 and from the chromosome 19 linkage group bounded by LE and SE. Evidence is presented for a possible location of YT on the short arm of chromosome 6 distal to F13A.

The preferred conformation and conformational dynamics of 2,2,3,4-tetramethyl-3- t -butylpentane, 2,2,4-trimethyl-3- t -butyl-pentane, and its cyclic analogue cis-2,2,4,6-6-pentamethyl- iso -propylcyclohexane are determined by dynamic nmr spectroscopy. Molecular Mechanics calculations for each compound help to illuminate the interpretation of the experimental measurements. In each case the most significant potential minima are two stable distorted gauche -ones separated by about 180° of rotation, and a much less stable trans -one, so the rotational barrier is two-fold.

Using a cell with horizontally mounted membranes, volume flux was measured as a function of gravitational geometry. Water was placed on one side of the membrane. The opposite side of the membrane was exposed to either aqueous glucose solutions, with densities greater than water; or aqueous ethanol, less dense than water; or ethanol—glucose—water solutions. In all cases, the osmotic pressure gradient generated volume flux from water to the solution. No mechanical stirring was used. Experiments were performed first with water above the membrane and the solution below it. They were then repeated with water below and the solution above the membrane. In all cases, volume flux was significantly larger when the denser liquid was above the membrane. Mach—Zehnder interferograms were obtained for the interface region of the water—membrane—0.1 M glucose system, Results show directly that boundary layers are substantially larger and more uniform with the lower-density liquid above the membrane than with the opposite geometry. These experimental findings are interpreted in terms of a convective gravitational instability that reduces boundary layer dimensions and increases volume flux. Following Rayleigh—Tavlor analysis of fluid gravitational stability, a concentration-gradient Rayleigh Number is developed and used in a mathematical model for gravitationally sensitive volume flux.

Using microprocessor based instrumentation, it is shown that the technique of variable amplitude pseudo-derivative normal pulse (pdnp) polarography can be extended to three dimensions with the measurement of current-time profiles on each pulse. Theory is presented for electrode processes with slow electron transfer and the ability to obtain variable, amplitude, variable time data in a higly, sensitive pulse mode from a single polarogram is considered to be most advantageous. The analytical application of this three-dimensional technique is experimentally examined in this work as an indicator of kinetic complications which lead to unrecognized forms of interference in the determination of unknown samples when standard analytical procedures are used. The combination of higher sensitivity, simpler theory and instrumentation, and greater versatility than differential pulse polarography should make the technique attractive in routine analytical chemistry.

Burning methanol and ethanol generate formic acid and acetic acid, respectively, as reaction products. These acids, concentrated in the liquid during the fires, cause electrochemical corrosion and rust formation on metal substrates. In these experiments, small amounts of alcohol were burnt on 1020 steel coupons. Corrosion products were analysed by FT-IR spectroscopy and by microscopy. Rates of rust formation were measured gravimetrically for various alcohol solutions, then compared with rates of deposit formation beneath fires of iso-octane. In other experiments, acidity changes in liquid methanol and ethanol were measured as larger volumes of these fuels were burnt in beakers. Observed acidity increase during the pool fires is consistent with acid concentrations necessary to produce metal corrosion.

Summary Odds favouring Do: PGD linkage (ž+ 3.56 at θ= 0.23) based on the average antilod are 920:20≃46:1. If Do is located on chromosome 1 it lies distal to PGD and recombination between PGD and Do occurs more frequently in male than in female meioses. Our data do not support Do:GC linkage.