Numerical modelling of electric conductance of a thin sheet

In this paper the numeric modelling of total resistance of a thin sheet, with local conductivity in randomly distributed grains higher then is that of the basic matrix, is presented. The 2D model is formed by a structure of longitudinal and transversal conductors interconnected in nodes of a square net. In all nodes, using iteration procedure, the potential is determined from which the conductance of sheet is computed between two touching electrodes. The described model can be used to imitate the behaviour of heterogeneous thin conducting sheets prepared by different techniques. The model was verified in some cases where the net resistance is well known from the theory

Managing Water under Uncertainty and Risk: The United Nations World Water Development Report 4

This report introduces new aspects of water issues: 1) it reintroduces the 12 challenge area reports that provided the foundation for the first two World Water Development Reports (WWDR); 2) 4 new reports on water quality, groundwater, gender, and desertification, land degradation and drought; 3) in recognition that the global challenges of water can vary considerably across countries and regions, a series of 5 regional reports have been included; 4) a deeper analysis of the main external forces of freshwater resources and possibilities for their future evolution; 5) managing water under uncertainty and risk

k-Dirac operator and parabolic geometries

The principal group of a Klein geometry has canonical left action on the homogeneous space of the geometry and this action induces action on the spaces of sections of vector bundles over the homogeneous space. This paper is about construction of differential operators invariant with respect to the induced action of the principal group of a particular type of parabolic geometry. These operators form sequences which are related to the minimal resolutions of the k-Dirac operators studied in Clifford analysis

Differential activity and secretion of multiple proteinases in vegetative amoebae and in germinating spores of the cellular slime mold Dictyostelium discoideum.

Lysosomal enzymes in the cellular slime mold Dictyostelium discoideum are differentially secreted during growth and starvation. Axenic amoebae linearly secreted over 30% of the total acid phosphatase activity during starvation in phosphate buffer. Addition of sucrose stimulated secretion of acid phosphatase; over 70% of the total enzyme activity was rapidly released. Moreover, the secretion kinetics of the enzyme activity shifted to a sigmoidal pattern resembling the complex secretion kinetics of other lysosomal enzymes. In an extension of these findings proteinase secretion was examined during starvation using three peptide-nitroanilide substrates N-benzoyl-L-prolyl-L-phenylalanyl-L-arginine 4-nitroanilide (BzPFR), N-carbobenzoxy-L-arginyl-L-arginine 4-nitroanilide (ZRR), and N-carbobenzoxy-L-tyrosyl-L-lysyl-L-arginine 4-nitroanilide (ZYKR). Proteinase activity was also examined in spores and during spore germination under various activation treatments. Dormant spores contained a major 58 kDa aspartic proteinase, designated ddAP58. Matrix material contained a novel 18 kDa cysteine proteinase, named ddCP18. During spore germination a decrease in intracellular ddAP58 activity heralded the appearance of two new cysteine proteinase activities, designated ddCP43 and ddCP48. Increases in BzPFRase and ZYKRase activities were also observed during emergence of myxamoebae. The use of different spore activation treatments, which altered the timing of events during germination, revealed that ZYKRase activity could be uncoupled from emergence. (Abstract shortened by UMI.)Dept. of Biological Sciences. Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis1991 .F735. Source: Masters Abstracts International, Volume: 31-01, page: 0210. Thesis (M.Sc.)--University of Windsor (Canada), 1991

On the maximal sum of exponents of runs in a string

A run is an inclusion maximal occurrence in a string (as a subinterval) of a repetition $v$ with a period $p$ such that $2p \le |v|$. The exponent of a run is defined as $|v|/p$ and is $\ge 2$. We show new bounds on the maximal sum of exponents of runs in a string of length $n$. Our upper bound of $4.1n$ is better than the best previously known proven bound of $5.6n$ by Crochemore & Ilie (2008). The lower bound of $2.035n$, obtained using a family of binary words, contradicts the conjecture of Kolpakov & Kucherov (1999) that the maximal sum of exponents of runs in a string of length $n$ is smaller than $2n$Comment: 7 pages, 1 figur

Revision to Nomenclature of the Zarah Subgroup of the Kansas City Group (Pennsylvanian) in Kansas

This paper provides a summary review of proposed nomenclatural revisions to the Zarah Subgroup of the Kansas City Group (Pennsylvanian) in Kansas and outlines changes adopted by the Kansas Geological Survey. The Iola Limestone, which comprises in ascending order the Paola Limestone, Muncie Creek Shale, and Raytown Limestone Members, is now considered the basal formation of the Zarah Subgroup. We reinstate the overlying Liberty Memorial Shale as originally defined by Clair (1943) in the area of Kansas City, Missouri. We also restrict the Wyandotte Limestone to include only, in ascending order, the Frisbie Limestone, Quindaro Shale, and Argentine Limestone Members. Furthermore, the Lane Shale is restricted in use and encompasses all strata within the shale-dominated interval between the top of the Argentine Limestone Member of the Wyandotte Limestone and the base of the overlying Plattsburg Limestone. Within the revised Lane Shale, the KGS now formally recognizes, in ascending order, the Lower Farley Limestone, Middle Farley Shale, and Upper Farley Limestone Members. The Bonner Springs Shale is now demoted in rank and included as the uppermost member within the Lane Shale.

The BaBar Event Building and Level-3 Trigger Farm Upgrade

The BaBar experiment is the particle detector at the PEP-II B-factory facility at the Stanford Linear Accelerator Center. During the summer shutdown 2002 the BaBar Event Building and Level-3 trigger farm were upgraded from 60 Sun Ultra-5 machines and 100MBit/s Ethernet to 50 Dual-CPU 1.4GHz Pentium-III systems with Gigabit Ethernet. Combined with an upgrade to Gigabit Ethernet on the source side and a major feature extraction software speedup, this pushes the performance of the BaBar event builder and L3 filter to 5.5kHz at current background levels, almost three times the original design rate of 2kHz. For our specific application the new farm provides 8.5 times the CPU power of the old system.Comment: Talk from the 2003 Computing in High Energy and Nuclear Physics (CHEP03), La Jolla, Ca, USA, March 2003, 4 pages, 1 eps figure, PSN MOGT00

Amperometric separation-free immunosensor for real-time environmental monitoring

Immunoanalytical techniques have found widespread use due to the characteristics of specificity and wide applicability for many analytes, from large polymer antigens, to simple haptens, and even single atoms. Electrochemical sensors offer benefits of technical simplicity, speed and convenience via direct transduction to electronic equipment. Together, these two systems offer the possibility of a convenient, ubiquitous assay technique with high selectivity. However, they are still not widely used, mainly due to the complexity of the associated immunoassay methodologies. A separation-free immunoanalytical technique is described here, which has allowed for the analysis of atrazine in real time and in both quasi-equilibrium and stirred batch configurations. It illustrated that determinations as low as 0.13mM (28 ppb) could be made using equilibrium incubation with an analytical range of 0.1–10mM. Measurements could be made between 1 and 10 mM within several minutes using a real-time, stirred batch method. This system offers the potential for fast, simple, cost-effective biosensors for the analysis of many substances of environmental, biomedical and pharmaceutical concern