Ground Ring Of Two Dimensional String Theory

String theories with two dimensional space-time target spaces are characterized by the existence of a ``ground ring'' of operators of spin $(0,0)$. By understanding this ring, one can understand the symmetries of the theory and illuminate the relation of the critical string theory to matrix models. The symmetry groups that arise are, roughly, the area preserving diffeomorphisms of a two dimensional phase space that preserve the fermi surface (of the matrix model) and the volume preserving diffeomorphisms of a three dimensional cone. The three dimensions in question are the matrix eigenvalue, its canonical momentum, and the time of the matrix model

Control of Meloidogyne chitwoodi (Columbia root-knot nematode) by microbial soil inoculants in potatoes (Solanum tuberosum)

Includes bibliographical references.2022 Fall.Columbia root-knot nematode (Meloidogyne chitwoodi Golden et al) is a major pest in commercial potato production in the northwestern, United States of America. M. chitwoodi infestation is widespread throughout the potato (Solanum tuberosum) growing regions of the U.S and other areas of the world. Meloidogyne spp. causes severe crop damage and economic losses in a broad range of economically important crops. Traditionally, M. chitwoodi has been controlled by the applications of chemical-based soil fumigants and nematicides. Chemical based controls have shown good effect at controlling M. chitwoodi, but due to their human toxicity, possible damage to the environment, development of nematode resistance to chemical nematicides, decreased availability of labeled chemical nematicides and the high cost of chemical nematicides there is a need for alternative methods to control M. chitwoodi. Specific soil microorganisms have been found to be antagonistic and parasitic to M. chitwoodi and other Meloidogyne spp. in potatoes and several other crops. It has also been proposed that the use of soil microorganisms that are antagonistic and parasitic to plant parasitic nematodes are an essential component to long term sustainable Integrated Nematode Management (INM). Due to the agricultural need for the development of alternative control methods of Meloidogyne spp. in crop production worldwide two commercially available microbial soil inoculant products were tested under greenhouse and open-field conditions. The two commercially available microbial soil inoculant products that were tested are NemaRoot, which contains Purpureocillium lilacinus (formally known as Paecilomyces lilacinus) and BioFit N, which contains Azotobacter chroccum, Bacillus subtilis, Bacillus megaterium, Bacillus mycoides, and Trichoderma harzianum. Previous findings have shown that Bacillus subtilis, Bacillus megaterium, Trichoderma harzianum and Purpureocillium lilacinus all have the ability to control Meloidogyne spp. to varying degrees in a number of diverse crops. The greenhouse experiments that were conducted for this research showed that NemaRoot was able to reduce M. chitwoodi root galling by 64% (P < 0.001), eggs by 74% (P < 0.001) to 91% (P < 0.001), second-stage juveniles in the substrate by 80% (P < 0.001), the reproductive factor by 67% (P < 0.001) to 80% (P < 0.001) and potato tuber damage by 77% (P < 0.001) to 82% (P < 0.001) in potatoes. The greenhouse experiments also showed that BioFit N was able to reduce M. chitwoodi root galling by 73% (P < 0.001, eggs by 81% (P < 0.001) to 97% (P < 0.001), second-stage juveniles in the substrate by 81% (P < 0.001), the reproductive factor by 82% (P < 0.001) to 87% (P < 0.001) and potato tuber damage by 78% (P < 0.001) to 78% (P < 0.001) in potatoes. The commercial open-field potato experiment showed that 2, 3 and 4 applications of BioFit N at a rate of 1.12 kg/ha per application were able to control M. chitwoodi tuber damage as well as 2 applications of Vydate (Oxamyl) at a rate of 2.2 L/ha per application. These results show that biocontrol of M. chitwoodi with microbial soil inoculants are an effective control method; especially, when used as a part of an Integrated Nematode Management (INM) strategy

A rigid irregular connection on the projective line

In this paper we construct a connection on the trivial G-bundle on the projective line for any simple complex algebraic group G, which is regular outside of the points 0 and infinity, has a regular singularity at the point 0, with principal unipotent monodromy, and has an irregular singularity at the point infinity, with slope 1/h, the reciprocal of the Coxeter number of G. This connection, which admits the structure of an oper in the sense of Beilinson and Drinfeld, appears to be the characteristic 0 counterpart of a hypothetical family of l-adic representations, which should parametrize a specific automorphic representation under the global Langlands correspondence. These l-adic representations, and their characteristic 0 counterparts, have been constructed in some cases by Deligne and Katz. Our connection is constructed uniformly for any simple algebraic group, and characterized using the formalism of opers. It provides an example of the geometric Langlands correspondence with wild ramification. We compute the de Rham cohomology of our connection with values in representations of G, and describe its differential Galois group as a subgroup of G.Comment: 38 pages, the version accepted for publication in Annals of Mathematics (Section 5.1 added about twisted opers

Cooperative Binding of Heat Shock Factor to the Yeast \u3ci\u3eHSP82\u3c/i\u3e Promoter In Vivo and In Vitro

revious work has shown that heat shock factor (HSF) plays a central role in remodeling the chromatin structure of the yeastHSP82 promoter via constitutive interactions with its high-affinity binding site, heat shock element 1 (HSE1). The HSF-HSE1 interaction is also critical for stimulating both basal (noninduced) and induced transcription. By contrast, the function of the adjacent, inducibly occupied HSE2 and -3 is unknown. In this study, we examined the consequences of mutations in HSE1, HSE2, and HSE3 on HSF binding and transactivation. We provide evidence that in vivo, HSF binds to these three sites cooperatively. This cooperativity is seen both before and after heat shock, is required for full inducibility, and can be recapitulated in vitro on both linear and supercoiled templates. Quantitative in vitro footprinting reveals that occupancy of HSE2 and -3 by Saccharomyces cerevisiae HSF (ScHSF) is enhanced ∼100-fold through cooperative interactions with the HSF-HSE1 complex. HSE1 point mutants, whose basal transcription is virtually abolished, are functionally compensated by cooperative interactions with HSE2 and -3 following heat shock, resulting in robust inducibility. Using a competition binding assay, we show that the affinity of recombinant HSF for the full-length HSP82promoter is reduced nearly an order of magnitude by a single-point mutation within HSE1, paralleling the effect of these mutations on noninduced transcript levels. We propose that the remodeled chromatin phenotype previously shown for HSE1 point mutants (and lost in HSE1 deletion mutants) stems from the retention of productive, cooperative interactions between HSF and its target binding sites

Rapid cognitive improvement in Alzheimer's disease following perispinal etanercept administration

Substantial basic science and clinical evidence suggests that excess tumor necrosis factor-alpha (TNF-alpha) is centrally involved in the pathogenesis of Alzheimer's disease. In addition to its pro-inflammatory functions, TNF-alpha has recently been recognized to be a gliotransmitter that regulates synaptic function in neural networks. TNF-alpha has also recently been shown to mediate the disruption in synaptic memory mechanisms, which is caused by beta-amyloid and beta-amyloid oligomers. The efficacy of etanercept, a biologic antagonist of TNF-alpha, delivered by perispinal administration, for treatment of Alzheimer's disease over a period of six months has been previously reported in a pilot study. This report details rapid cognitive improvement, beginning within minutes, using this same anti-TNF treatment modality, in a patient with late-onset Alzheimer's disease. Rapid cognitive improvement following perispinal etanercept may be related to amelioration of the effects of excess TNF-alpha on synaptic mechanisms in Alzheimer's disease and provides a promising area for additional investigation and therapeutic intervention

TWO NEW SHORT-PERIOD CEPHEIDS

The General Catalogue of Variable Stars gives periods of slightly less than three-quarters of a day for the stars NO Cas and CN Tau. However, new photometry demonstrates that their periods are actually 2.6 and 1.8 days, respectively, and they are thus classical Cepheids. Fourier decompositions of their light curves are performed, and they are found to be members of a class of Cepheids with periods less than three days which may be related to the s-Cepheids. These two stars represent the shortest and longest known members of this class and thus are very useful in defining its properties in the Fourier diagrams

Discrete fracture modeling for fractured reservoirs using Voronoi grid blocks

Fractured reservoirs are commonly simulated using the Dual Porosity model, but for many major fields, the model does not match field results. For these cases, it is necessary to perform a more complex simulation including either individual fractures or pseudofracture groups modeled in their own grid blocks. Discrete Fracture Modeling (DFN) is still a relatively new field, and most research on it up to this point has been done with Delaunay tessellations. This research investigates an alternative approach using Voronoi diagrams, yet applying the same DFN principles outlined in previous works. Through the careful positioning of node points, a grid of Voronoi polygons can be produced so that block boundaries fall along the fractures, allowing us to use the DFN simulation methods as proposed in the literature. Using Voronoi diagrams allows us to use far fewer polygons than the Delaunay approach, and also allows us to perfectly align flow so as to eliminate grid alignment errors that plagued previous static systems. The nature of the Voronoi polygon further allows us to simplify permeability calculations due to orthogonality and, by extension, is more accurate than the commonly used cornerpoint formulation for non-square grid blocks

MECHANICAL CHARACTERIZATION OF SHAPE MEMORY POLYMERS TO ASSESS CANDIDACY AS MORPHING AIRCRAFT SKIN

This thesis presents the results of research with the purpose of determining the mechanical properties of shape memory polymers and evaluating the material's potential use as a morphing aircraft skin. Morphing aircraft undergo large scale deformations to their wing planforms in order to perform better in different types of missions. The skin on the wing must be ductile enough to stretch but remain strong enough to withstand out of plane aerodynamic loads. Shape memory polymers exhibit large decreases in their elastic modulii when heated above a glass transition temperature which allows them to withstand large strains. This ability has lead to the belief that shape memory polymers could perform well as morphing aircraft skins. Several tests that reveal mechanical properties important to a morphing wing skin are performed on a commercially available shape memory polymer and the results are presented and discussed in this study.i