The prediction of mix design properties for dense graded bituminous mixtures

The purpose of this investigation was to ascertain the feasibility of interpolating values of the physical properties of a dense graded bituminous mix between known values. Also the effects of limestone mineral filler on the properties of a dense graded mix are evaluated. The variables in this study were mineral filler and asphalt cement. Control mixes were established at 2, 6 and 10 percent mineral filler and experimental mixes were prepared at 4 and 8 percent filler. The aggregate consisted of limestone and was mixed with an asphalt cement of 85-100 grade penetration. Al mixes were tested by the Marshall Method. The physical properties analyzed were stability, flow, unit weight, air voids and voids in the mineral aggregate. It was determined that interpolation between known values of the physical properties of a dense graded mix is valid for a specific range of asphalt contents and that asphalt content was critical at low (3-4 percent) and high (7-8 percent) ranges. Mineral filler increased the desirable properties of a bituminous mix up to a certain asphalt content and then the desirable properties diminished rapidly --Abstract, page ii

SIGNIFICANCE AND CONTROL OF FUNGAL DISEASES RELATED TO BIRD ROOSTS

Certain fungi have been found frequently as saprophytes in areas containing large amounts of bird excreta. These fungi have the ability to survive, multiply, and cause disease once they have entered a host. Two of these are Crypto-coccus neoformans and Histoplasma capsulatum. Both may easily become airborne and be disseminated throughout an area by the prevailing winds. C. neo-formans is commonly isolated from the excreta of pigeon habitats, and in turn has been associated with clinical cases of cryptococcosis, while blackbird roosts, harboring H. capsulatum, have been responsible for several outbreaks of histoplasmosis. When either of these fungi have become established in nature, the sites may become foci for infection and epidemics may occur if the sites are disturbed. This has led to investigation of these organisms with respect to: 1) the frequency of isolation of H. capsulatum from the soil beneath blackbird roosts in a histoplasmosis endemic area; 2) the infectivity of undisturbed roosts positive for H. capsulatum; and 3) the effectiveness of chemical decontamination of areas containing C. neoformans or H. capsulatum

A Fully Quantum Calculation of Broadening and Shifting Coefficients of the D\u3csub\u3e1\u3c/sub\u3e and D\u3csub\u3e2\u3c/sub\u3e spectral lines of alkali-metal atoms colliding with noble-gas atoms

We use the Baranger model to compute collisional broadening and shift rates for the D1 and D2 spectral lines of M + Ng, where M = K, Rb, Cs and Ng = He, Ne, Ar. Scattering matrix elements are calculated using the channel packet method, and non-adiabatic wavepacket dynamics are determined using the split-operator method together with a unitary transformation between adiabatic and diabatic representations. Scattering phase shift differences are weighted thermally and are integrated over temperatures ranging from 100 K to 800 K. We find that predicted broadening rates compare well with experiment, but shift rates are predicted poorly by this model because they are extremely sensitive to the near-asymptotic behavior of the potential energy surfaces. © 2020 The Author(s). Published by IOP Publishing Ltd

Identifying the strengths and weaknesses of conservation planning at different scales: the Coral Triangle as a case study

Each year, hundreds of conservation plans are developed to direct limited resources toward conservation in priority areas. Conservation plans are developed at different levels, defined here as points on a range of spatial extent varying from global to local. However, approaches to integrate plans effectively across levels remain elusive. To plan across multiple levels most effectively, the relative strengths and weaknesses of planning at different levels must be understood. Taking the Coral Triangle region of the western Pacific Ocean as a case study, we apply an adapted social-ecological system (SES) framework to assess the scalar coverage of conservation plans, i.e., the extent to which plans developed at one level adequately consider the social and ecological levels and components (i.e., resource units, resource systems, governance systems, actors) of an SES. No conservation plans we assessed had complete cross-level coverage. Plans most adequately addressed social and ecological components at the same level of planning and, to a lesser extent, lower levels. In line with previous literature suggesting that social factors are most relevant at local levels, we found that local-level plans engaged with the greatest number of stakeholder groups, whereas higher level plans more adequately addressed ecological components. Given that it appears more practicable for higher level plans to consider components at lower levels, the onus should fall on higher level planning to link to lower levels. Achieving complete cross-level coverage will require vertical interactions between planning processes at different levels, and conceiving of planning processes across all levels as connected planning systems. We demonstrate how an adapted SES framework can be used by conservation planners to assess the cross-level coverage of their own plans and to formulate appropriate conservation objectives to address social and ecological components at different levels

The Effect of Wavelet Families on Watermarking

With the advance of technologies such as the Internet, Wi-Fi Internet availability and mobile access, it is becoming harder than ever to safeguard intellectual property in a digital form. Digital watermarking is a steganographic technique that is used to protect creative content. Copyrighted work can be accessed from many different computing platforms; the same image can exist on a handheld personal digital assistant, as well as a laptop and desktop server computer. For those who want to pirate, it is simple to copy, modify and redistribute digital media. Because this impacts business profits adversely, this is a highly researched field in recent years. This paper examines a technique for digital watermarking which utilizes properties of the Discrete Wavelet Transform (DWT). The digital watermarking algorithm is explained. This algorithm uses a database of 40 images that are of different types. These images, including greyscale, black and white, and color, were chosen for their diverse characteristics. Eight families of wavelets, both orthogonal and biorthogonal, are compared for their effectiveness. Three distinct watermarks are tested. Since compressing an image is a common occurrence, the images are compacted to determine the significance of such an action. Different types of noise are also added. The PSNR for each image and each wavelet family is used to measure the efficacy of the algorithm. This objective measure is also used to determine the influence of the mother wavelet. The paper asks the question: “Is the wavelet family chosen to implement the algorithm of consequence?” In summary, the results support the concept that the simpler wavelet transforms, e.g. the Haar wavelet, consistently outperform the more complex ones when using a non-colored watermark

Geminate recombination of hydroxyl radicals generated in 200 nm photodissociation of aqueous hydrogen peroxide

The picosecond dynamics of hydroxyl radicals generated in 200 nm photoinduced dissociation of aqueous hydrogen peroxide have been observed through their transient absorbance at 266 nm. It is shown that these kinetics are nearly exponential, with a decay time of ca. 30 ps. The prompt quantum yield for the decomposition of H2O2 is 0.56, and the fraction of hydroxyl radicals escaping from the solvent cage to the water bulk is 64-68%. These recombination kinetics suggest strong caging of the geminate hydroxyl radicals by water. Phenomenologically, these kinetics may be rationalized in terms of the diffusion of hydroxide radicals out of a shallow potential well (a solvent cage) with an Onsager radius of 0.24 nm.Comment: 14 pages, 1 figur