Water vapor in the lower stratosphere measured from aircraft flight

Water vapor in the lower stratosphere was measured in situ by two aluminum oxide hygrometers mounted on the nose of an RB57 aircraft. Data were taken nearly continuously from January to May 1974 from an altitude of approximately 11 km to 19 km as the aircraft flew between 70 deg N and 50 deg S over the land areas in the Western Hemisphere. Pseudomeridional cross sections of water vapor and temperature are derived from the flight data and show mixing ratios predominantly between 2 and 4 micron gm/gm with an extreme range of 1 to 8 micron gm/gm. Measurement precision is estimated by comparing the simultaneously measured values from the two flight hygrometer systems. Accuracy is estimated to be about + or - 40 percent at 19 km. A height-averaged latitudinal cross section of water vapor shows symmetry of wet and dry zones

Experimental archeology and serious games: challenges of inhabiting virtual heritage

Experimental archaeology has long yielded valuable insights into the tools and techniques that featured in past peoples’ relationship with the material world around them. However, experimental archaeology has, hitherto, confined itself to rigid, empirical and quantitative questions. This paper applies principles of experimental archaeology and serious gaming tools in the reconstructions of a British Iron Age Roundhouse. The paper explains a number of experiments conducted to look for quantitative differences in movement in virtual vs material environments using both “virtual” studio reconstruction as well as material reconstruction. The data from these experiments was then analysed to look for differences in movement which could be attributed to artefacts and/or environments. The paper explains the structure of the experiments, how the data was generated, what theories may make sense of the data, what conclusions have been drawn and how serious gaming tools can support the creation of new experimental heritage environments

Evaluating the Applicability of the Fokker-Planck Equation in Polymer Translocation: A Brownian Dynamics Study

Brownian dynamics (BD) simulations are used to study the translocation dynamics of a coarse-grained polymer through a cylindrical nanopore. We consider the case of short polymers, with a polymer length, N, in the range N=21-61. The rate of translocation is controlled by a tunable friction coefficient, gamma_{0p}, for monomers inside the nanopore. In the case of unforced translocation, the mean translocation time scales with polymer length N as ~ (N-N_p)^alpha, where N_p is the average number of monomers in the nanopore. The exponent approaches the value alpha=2 when the pore friction is sufficiently high, in accord with the prediction for the case of the quasi-static regime where pore friction dominates. In the case of forced translocation, the polymer chain is stretched and compressed on the cis and trans sides, respectively, for low gamma_{0p}. However, the chain approaches conformational quasi-equilibrium for sufficiently large gamma_{0p}. In this limit the observed scaling of with driving force and chain length supports the FP prediction that is proportional to N/f_d for sufficiently strong driving force. Monte Carlo simulations are used to calculate translocation free energy functions for the system. The free energies are used with the Fokker-Planck equation to calculate translocation time distributions. At sufficiently high gamma_{0p}, the predicted distributions are in excellent agreement with those calculated from the BD simulations. Thus, the FP equation provides a valid description of translocation dynamics for sufficiently high pore friction for the range of polymer lengths considered here. Increasing N will require a corresponding increase in pore friction to maintain the validity of the FP approach. Outside the regime of low N and high pore friction, the polymer is out of equilibrium, and the FP approach is not valid.Comment: 13 pages, 11 figure

Court Review: Volume 41, Issue 1 - Recent Evaluative Research on Jury Trial Innovations

During the past decade, state jury reform commissions, many individual federal and state judges, and jury scholars have advocated the adoption of a variety of innovative trial procedures to assist jurors in trials. These include reforms as prosaic as allowing juror note taking and furnishing jurors with copies of written instructions, through more controversial changes, such as allowing jurors to ask questions of witnesses or permitting them to discuss the case together during breaks in the trial. Accounts of the nature and purpose of the innovations and the pace of change are found in this issue of Court Review1 and elsewhere. These innovations are now catalogued in convenient form, accompanied by practical guidance for judges. Many jury trial reforms reflect growing awareness of best practices in education and communication as well as research documenting that jurors take an active rather than a passive approach to their decision-making task. Traditional adversary jury trial procedures often appear to assume that jurors are blank slates, who will passively wait until the end of the trial and the start of jury deliberations to form opinions about the evidence. However, we now know that jurors quite actively engage in evidence evaluation, developing their opinions as the trial progresses. It makes sense to revise trial procedures so they take advantage of jurors’ decision-making tendencies and strengths. Although reform groups have endorsed many of these innovations, until recently there was only modest evidence about their impact in the courtroom. Now, substantial research on the effects of most of the reforms on juror comprehension and juror satisfaction with the trial has been completed and reported. Data are now available to judges and others seeking reliable empirical support for the changes to the traditional jury trial. This article will describe the methods used to study juries and jury trials and present recent data now available for each of the major proposed innovations. We also draw on new findings from our own recent research testing the comparative advantages of jury innovations for understanding complex scientific evidence

Arthrospira (Spirulina) in tannery wastewaters. Part 2: Evaluation of tannery wastewater as production media for the mass culture of Arthrospira biomass

Mass blooms of Arthrospira (Spirulina) have been reported in waste stabilisation ponds treating tannery wastewaters and have been linked to a reduction in odour emissions in these systems. However, these blooms are unstable and unreliable, forming and disappearing in an apparently unpredictable manner, and they have remained poorly understood. Controlled production of Arthrospira biomass in this medium could not only be used to enable a more predictable control of odour in these systems (as detailed in Part 1 of this report), but could also provide a biomass product with external value. Techno-economic studies of microalgal biomass production have identified the cost of growth media formulation as a critical driver in the profitability of the algal biotechnology enterprise. Apart from the potential feed value of Arthrospira biomass as a product, the renewed interest in, and possibly marginal economics of, biofuels production from the microalgae has refocused attention on the possible advantages of wastewater use as low-cost production media. Part 2 of this study reports the investigation of factors regulating Arthrospira growth in the tannery wastewater medium and thus requiring active control in order to optimise biomass production. It was shown that Arthrospira growth in this high-protein, low-carbonate medium is under ammonia control, rather than nutrient limitation, as may previously have been thought. It was also shown that an effective mass culture strategy in this medium would require a maximum effluent loading rate that operates as a function of the optimised ammonia removal rate. Growth optima were demonstrated for ammonia and bicarbonate levels of 20 mg∙ℓ-1 and 12–17 g∙ℓ-1, respectively, and inhibition of growth was demonstrated at ammonia levels above 60 mg∙ℓ-1. Both autotrophic and mixotrophic growth of Arthrospira was observed and organic uptake may contribute to a stimulation of biomass production compared to growth in defined inorganic media. Heavy metal accumulation may present a toxicity hazard where biomass is targeted for use in animal feed rations. A heavy metals removal step was investigated involving the passage of the tannery effluent through an anaerobic sulphide-generating compartment in a primary pond, prior to its use in Arthrospira production. An acceptable Arthrospira feed-grade biomass was produced in this way. These results indicate potential cost-benefit advantages in the use of tannery effluent-based growth media for Arthrospira biomass production, and waste nutrient recovery may mitigate negative energy yield problems where the biomass is further processed in biofuels manufacture.Keywords: Spirulina; Arthrospira; microalgal biomass; biofuels; tannery; wastewater; waste stabilisation pond

Synthesis and Properties of Dipyridylcyclopentenes

A short and general route to the substituted dipyridylcyclopentenes was explored and several new compounds belonging to this new group of diarylethenes were synthesized. The study of their photochromic and thermochromic properties shows that the rate of the thermal ring opening is strongly dependent on the polarity of the solvent.

Spectral geometry, homogeneous spaces, and differential forms with finite Fourier series

Let G be a compact Lie group acting transitively on Riemannian manifolds M and N. Let p be a G equivariant Riemannian submersion from M to N. We show that a smooth differential form on N has finite Fourier series if and only if the pull back has finite Fourier series on

Feasibility study of a synthesis procedure for array feeds to improve radiation performance of large distorted reflector antennas

The topics covered include the following: (1) performance analysis of the Gregorian tri-reflector; (2) design and performance of the type 6 reflector antenna; (3) a new spherical main reflector system design; (4) optimization of reflector configurations using physical optics; (5) radiometric array design; and (7) beam efficiency studies