On U_q(SU(2))-symmetric Driven Diffusion

We study analytically a model where particles with a hard-core repulsion diffuse on a finite one-dimensional lattice with space-dependent, asymmetric hopping rates. The system dynamics are given by the \mbox{U$_{q}$[SU(2)]}-symmetric Hamiltonian of a generalized anisotropic Heisenberg antiferromagnet. Exploiting this symmetry we derive exact expressions for various correlation functions. We discuss the density profile and the two-point function and compute the correlation length $\xi_s$ as well as the correlation time $\xi_t$. The dynamics of the density and the correlations are shown to be governed by the energy gaps of a one-particle system. For large systems $\xi_s$ and $\xi_t$ depend only on the asymmetry. For small asymmetry one finds $\xi_t \sim \xi_s^2$ indicating a dynamical exponent $z=2$ as for symmetric diffusion.Comment: 10 pages, LATE

Exact results for one dimensional stochastic cellular automata for different types of updates

We study two common types of time-noncontinuous updates for one dimensional stochastic cellular automata with arbitrary nearest neighbor interactions and arbitrary open boundary conditions. We first construct the stationary states using the matrix product formalism. This construction then allows to prove a general connection between the stationary states which are produced by the two different types of updates. Using this connection, we derive explicit relations between the densities and correlation functions for these different stationary states.Comment: 7 pages, Late

Plant viruses

1. Barley Yellow Dwarf Virus: G.D. McLean, T.N. Khan, J. Sandow. 2. Clover Viruses: G.D. McLean, J. Sandow. BYDV: Survey of incidence - Locations: Esperance (80ES53) sown June 27, 1980 Williams (80NA35) sown June 19, 1980 Kojonup (80KA28) sown June 19, 1980 Bokerup (80MA11) sown July 8, 1980 Jerramungup (80JE14) sown June 26, 1980 Albany (80AL30) sown July 3, 1980 Busselton (80BU3) sown July 8, 1980 Bridgetown (80BR19) sown June s, 1980 Northam (80N026) sown June 16, 1980 All these plots were located at the cultivar variety trial sites. Sites varied considerably in BYDV incidence as well as in rate of disease progress. There was evidence of recovery in some plants, and at Narrogin most infected plants recovered. Taking the mean disease score in the last recording; Manjimup, Albany, Bridgetown, Katanning and Narrogin showed decreasing amounts of incidence in that order. The lower rainfall sites (Katanning and Narrogin) had a much lower incidence of BYDV than the higher rainfall sites. Clover Viruses - 80AL29, 80BR15, 80BU2, 80BY6, 80ES52, 80MA10

Barley yellow dwarf virus in barley and oats (79MT20, 79PE13) Experimental summary 1979

(1) Yield assessments have continued similar to those used in 1977 and 1978. Essentially, plants with symptoms typical of BYDV are marked in the early spring as well as a similar number without symptoms. Yield differences were obtained both for Clipper Barley and an oats variety. (2) Two pilot experiments using viruliferous aphids were carried out at Mount Barker (79MT20) and at South Perth · (79PE13). Both Rhopalosiphum padi and R. maidis were used. Infection at Mt Barker failed, and therefore no data is presented. The Perth experiment was planted on August 31, 1979. The original plan was to have two treatments, i.e. Aphid infestation vs. Control in 4 replications. However, as two different species of aphid became available, the experiment was split into two smaller ones, each using a different species of aphid with 2 replications. RESULTS: See Tables 1 and 2

Electronic correlation effects and the Coulomb gap at finite temperature

We have investigated the effect of the long-range Coulomb interaction on the one-particle excitation spectrum of n-type Germanium, using tunneling spectroscopy on mechanically controllable break junctions. The tunnel conductance was measured as a function of energy and temperature. At low temperatures, the spectra reveal a minimum at zero bias voltage due to the Coulomb gap. In the temperature range above 1 K the Coulomb gap is filled by thermal excitations. This behavior is reflected in the temperature dependence of the variable-range hopping resitivity measured on the same samples: Up to a few degrees Kelvin the Efros-Shkovskii ln$R \propto T^{-1/2}$ law is obeyed, whereas at higher temperatures deviations from this law are observed, indicating a cross-over to Mott's ln$R \propto T^{-1/4}$ law. The mechanism of this cross-over is different from that considered previously in the literature.Comment: 3 pages, 3 figure

Geochemical Dispersion of Elements and Their Correlation with Gold in the Regolith at the Tetteh Prospect of the Chirano Gold Mines in the Sefwi Belt of the Birimian, Southwestern Ghana

The processes controlling gold (Au) mineralization in Chirano, a gold prospect in south-western Ghana have been investigated using a detailed geochemical dataset of 45 variables from 197 sampling locations. The data were subjected to advanced statistical analyses and bivariate graphical interpretations in the light of the underlying lithology. Four processes of significance have been identified from the multivariate analysis in terms of the geochemistry of the soil in the area. The most important process accounts for almost half of the total variance in the dataset and also correlates strongly with Au. Although Arsenic (As) registers the highest loading under this factor, Aluminium (Al), Silver (Ag), Manganese (Mn), Copper (Cu), and Iron (Fe) record higher correlations and could serve as better pathfinders than As in the study area. This study also shows that there is a second, less prominent process contributing to the availability of Au in the area. This process ranks third amongst the processes of significance in terms of the geochemistry, and correlates negatively with As, suggesting that the latter is not suitable as a pathfinder for Au in the traditional sense. However, since this third process is weaker compared to the first, the implication of this interpretation may be limited to only some locations in the study area. In addition to the revelations from the multivariate statistics, the regolith in the study area has evolved over the years and therefore the changes in regolith should be factored into the exploration protocols. The pre-existing preserved surfaces were found to be masked predominantly by transported materials consisting of ferruginized and exotic sediments. Within the surficial regolith and especially in the Fe-oxyhydroxide rich horizons, Au concentrations increase to significant values that are higher than those of the bedrock or saprolite thereby showing the significant Au re-distribution within the regolith. This study also highlights the apparent Au depletion in the mottled clay zones and in the saprolite and the enrichment of the metal in lateritic residuum and the topsoil. The high Au expressions in the upper parts of the regolith generally are transported whereas the residual soil anomalies have low Au concentrations and do not merit further exploration follow up. Keywords: Regolith, Gold mineralization, Pathfinder elements, Chirano mine, Sefwi belt, southwestern Ghana

1981 Plant viruses

1, Clover viruses - 81HA6, 81MA9, 81BR14, 81BY12, 81BH5, 81AL38, 81ES39 OBJECTIVES: To determine the extent of the \u27Dinninup virus\u27 problem (sub. clover mottle). To further assess the incidence of red leaf virus to determine the incidence of bean yellow mosaic virus. To note the incidence of sub. clover stunt virus. A. BYDV: Survey of incidence - 81BU1, 81BU2, 81BR11, 81BR12, 81MA6, 81MA7, 81AL31, 81AL32, 81JE14, 81JE15, 81KA21, 81KA22, 81NA28, 81N031, 81ES38, 81E26. 2. Barley yellow dwarf virus. BYDV: Genotype x insecticide studies - 81MN14, 81MT29, 81E28, 81MN14. BYDV: differences amongst barley genotypes - 81C19, 81WH31, 81BA30. BYDV: Resistance and yield in CV.Shannon and CV. Proctor - 871BR13, 81MA8, 81AL36, 81JE17 Yield per plot and 100 seed weight - Albany 81AL36 Infection of BYDV in cereal genotypes at Manjimup ( 81MN13)

Status of a DEPFET pixel system for the ILC vertex detector

We have developed a prototype system for the ILC vertex detector based on DEPFET pixels. The system operates a 128x64 matrix (with ~35x25 square micron large pixels) and uses two dedicated microchips, the SWITCHER II chip for matrix steering and the CURO II chip for readout. The system development has been driven by the final ILC requirements which above all demand a detector thinned to 50 micron and a row wise read out with line rates of 20MHz and more. The targeted noise performance for the DEPFET technology is in the range of ENC=100 e-. The functionality of the system has been demonstrated using different radioactive sources in an energy range from 6 to 40keV. In recent test beam experiments using 6GeV electrons, a signal-to-noise ratio of S/N~120 has been achieved with present sensors being 450 micron thick. For improved DEPFET systems using 50 micron thin sensors in future, a signal-to-noise of 40 is expected.Comment: Invited poster at the International Symposium on the Development of Detectors for Particle, AstroParticle and Synchrotron Radiation Experiments, Stanford CA (SNIC06) 6 pages, 12 eps figure

Adelaide in-depth accident study 1975-1979. Part 2: Pedestrian accidents

This report contains descriptions of the causes and consequences of the pedestrian accidents contained in a representative sample of road traffic accidents to which an ambulance was called in metropolitan Adelaide. Reviews of the relevant characteristics of the pedestrians and drivers, the vehicles, and the road and traffic environment are also included. All but one of these 40 accidents occurred on busy roads. Some measures designed to increase the rate of flow of vehicular traffic are detrimental to the safety of the pedestrian, to the extent that some urban arterial roads are very hazardous for some pedestrians, particularly children and the elderly. The pedestrian was more likely to have been careless, or to have made a mistake, than was the driver, but alcohol intoxication was less apparent as a causal factor in these pedestrian accidents than in other types of accidents covered by this survey. The injuries sustained by the pedestrians were much more likely to be dangerous to life than were the injuries sustained by other road users involved in other types of accident. The front of the striking car, including the upper surface of the bonnet, accounted for more than half of the injuries. A number of possible countermeasures and topics worthy of further investigation are listed at the end of the report.A.J. McLean, N.D.Brewer, B.L. Sando

Adelaide in-depth accident study 1975-1979. Part 3: Pedal cycle accidents.

This report contains descriptions of the causes and consequences of the pedal cycle accidents contained in a representative sample of road traffic accidents to which an ambulance was called in metropolitan Adelaide. Reviews of the relevant characteristics of the cyclists and drivers, the vehicles, and the road and traffic environment are also included. One-third of these 22 accidents involved a child cyclist who was riding carelessly on a residential street. The other two-thirds mostly involved adult cyclists on arterial roads, and were a consequence of errors made equally by the cyclists and the drivers. Alcohol intoxication was not a significant factor in any of these accidents. Almost all of the cyclists were injured, and their injuries were often very severe. The front of the striking car caused two-thirds of the severe injuries. A number of possible countermeasures and topics worthy of further investigation are listed at the end of the report.A.J. McLean, N.D. Brewer, B.L. Sando