5,922 research outputs found

    On Fractional Instanton Numbers in Six Dimensional Heterotic E8 x E8 Orbifolds

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    We derive the precise relation between level matching condition and fractional instanton numbers in six dimensional, abelian and supersymmetric orbifolds of E8 x E8 heterotic string theory. The fractional part of the two E8 instanton numbers is explicitly calculated in terms of the gauge twist. This relation is then used to show that the classification of these orbifolds can be given in terms of flat bundles away from the orbifold singularities under the only constraint that the sum of the fractional parts of the gauge instanton numbers match the fractional part of the gravitational instanton number locally at every fixed point. This directly carries over to M-theory on S^1/Z_2Comment: latex2e, 12 pages; reference and comments adde

    Evaluating the Relationship Between Running Times and DNA Sequence Sizes using a Generic-Based Filtering Program.

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    Generic programming depends on the decomposition of programs into simpler components which may be developed separately and combined arbitrarily, subject only to well- defined interfaces. Bioinformatics deals with the application of computational techniques to data present in the Biological sciences. A genetic sequence is a succession of letters which represents the basic structure of a hypothetical DNA molecule, with the capacity to carry information. This research article studied the relationship between the running times of a generic-based filtering program and different samples of genetic sequences in an increasing order of magnitude. A graphical result was obtained to adequately depict this relationship. It was also discovered that the complexity of the generic tree program was O (log2 N). This research article provided one of the systematic approaches of generic programming to Bioinformatics, which could be instrumental in elucidating major discoveries in Bioinformatics, as regards efficient data management and analysis

    Genetic diversity, taxonomy and legumins implications of seed storage protein profiling in Fabaceae

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    Proteomic evidences can be pivotal to the discovery of new plant proteins and plant relationships, due to the diversity of form it can reveal. Seed storage protein profiles of 20 Fabaceae species: 4 grain - legumes and 16 non-pulses; of 16 genera and 10 tribes were analysed by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) to estimate protein content diversity and the possible genetic relatedness.28.3% similarity and 71.7% proteomic polymorphism was scored for the species. The high variability expressed by the lot reflects the genetic diversity amongst Fabaceae population. Dendrogram based on the proteomic data clustered the species into four groups. Aside two species, Albizia lebbeck and Albizia zygia belonging to the tribe Ingeae and those of the tribe Caesalpinieae, the other species clustered with several other non-traditional cohorts resulting in a rearrangement that showed least semblance with phylogenetic relationships based on traditional morphology taxonomic delimitation. The similarity in profiles can be preliminarily forensic for proteins of importance whether for nutritional, industrial or for improvement of existing crops or for entirely new plants as crops. The protein mix, and the resultant relationship based on seed storage proteins instigates a review of erstwhile taxonomic, agricultural and research perspectives for the Fabaceae

    Evaluation of Forearm Muscle Fatigue from Operating a Motorcycle Clutch

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    A laboratory experiment evaluated the effect of motorcycle clutch design on the electromyography (EMG) activity of the primary agonist finger flexor muscle in the forearm. The goal was to compare muscle fatigue resulting from operation of two different motorcycle clutches in simulated traffic. EMG activity from the flexor digitorum superficialis (FDS) muscle of 12 female and 11 males were recorded while each participant operated an existing motorcycle clutch (requiring 98 N peak force) as well as an alternate design (requiring 36 N peak force) during 60-minute simulations. Muscle fatigue was quantified by measuring the decrease in median frequency of the EMG signals. Compared to operating the existing clutch, male participants experienced a significant decrease in muscle fatigue between 14 to 31% when operating the alternate clutch. Females experienced a decrease of 27 to 49%. In addition to reduced muscle fatigue, the alternate clutch was overwhelmingly preferred by participants and was rated superior for ease of use and comfort. Results provide a better understanding of the effect of clutch design on riders’ muscular loading and implications for design improvements

    Brane Tensions and Coupling Constants from within M-Theory

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    Reviewing the cancellation of local anomalies of M-theory on R^10 x S^1/Z_2 the Yang-Mills coupling constant on the boundaries is rederived. The result is lambda^2 = 2^(1/3) (2 pi) (4 pi kappa^2)^(2/3) corresponding to eta = lambda^6/kappa^4 = 256 pi^5 in the `upstairs' units used by Horava and Witten and differs from their calculation. It is shown that these values are compatible with the standard membrane and fivebrane tensions derived from the M-theory bulk action. In view of these results it is argued that the natural units for M-theory on R^10 x S^1/Z_2 are the `downstairs' units where the brane tensions take their standard form and the Yang-Mills coupling constant is lambda^2 = 4 pi (4 pi kappa^2)^(2/3).Comment: 11 pages, no figures, Latex2e, amsmath, amsfonts, typo in abstract correcte

    Effects of deposit-feeding bivalve (Macomona liliana) density on intertidal sediment stability

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    Effects of macrofaunal feeding and bioturbation on intertidal sediment stability (u*crit) were investigated by manipulating density (0-3 x ambient) of the facultative deposit-feeding wedge shell (Macomona liliana) on the Tuapiro sandflat in Tauranga Harbour, New Zealand. Sediment stability increased up to 200% with decreasing M. liliana density and this was correlated with greater sediment microalgal biomass and mucilage content. The change in stability occurred despite homogeneity of grain size amongst experimental treatments, highlighting the importance of macrofaunal-microbial relationships in determining estuarine sediment erodibility

    Effects of Wrist Tendon Vibration on Targeted Upper-Arm Movements in Poststroke Hemiparesis

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    Background. Impaired motor control of the upper extremity after stroke may be related to lost sensory, motor, and integrative functions of the brain. Artificial activation of sensory afferents might improve control of movement by adding excitatory drive to sensorimotor control structures. The authors evaluated the effect of wrist tendon vibration (TV) on paretic upper-arm stability during point-to-point planar movements. Methods. TV (70 Hz) was applied to the forearm wrist musculature of 10 hemiparetic stroke patients as they made center-out planar arm movements. End-point stability, muscle activity, and grip pressure were compared as patients stabilized at the target position for trials completed before, during, and after the application of the vibratory stimulus. Results. Prior to vibration, hand position fluctuated as participants attempted to maintain the hand at the target after movement termination. TV improved arm stability, as evidenced by decreased magnitude of hand tangential velocity at the target. Improved stability was accompanied by a decrease in muscle activity throughout the arm as well as a mean decrease in grip pressure. Conclusions. These results suggest that vibratory stimulation of the distal wrist musculature enhances stability of the proximal arm and can be studied further as a mode for improving end-point stability during reaching in hemiparetic patients

    Synthesis, physical properties, antimicrobial potentials of some mixed antibiotics complexed with transition metals and their effects on alkaline phosphatase activities of selected rat tissues

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    Mixed ligand metal complexes of chloramphenicol and oxytetracycline were prepared by using Ni(II), Co(II) and Fe(III) metal chloride hexahydrate. They were characterized based on some physical technique and spectroscopic analysis such as AAS, UV, and IR spectroscopy. Based on the analytical and spectroscopic data, the complexes were proposed to have the formulae [ML1L2](Cl)n (where M = Ni(II), Co(II), Fe(III); L1 = chloramphenicol, L2 = oxytetracycline and n = 2 - 3). IR spectra suggested that both L1 and L2 coordinated to the metal ions in a terdentate manner with �(O-H), �(C=O) and �(N-H) as donor sites in each of the ligands. The complexes were proposed to be of octahedral. The synthesized complexes, in compares to their ligands, were screened for their antibacterial activity against isolated strains of Escherichia coli, Staphylococcus aureus and Klebsiella pneumonia by using diffusion method. The activity data showed the metal complexes to be more potent antibacterial than the parent drugs against the three species. Toxicology tests against some tissues of albino rat (Rattus novergicuss) revealed toxicity of the complexes as compared to the parent drugs. Ni(II) complex was found to possess no significant difference (P > 0.05) in alkaline phosphatase from both homogenates of liver and kidney and rat serum. However, Co(II) and Fe(III) complexes were found to significantly increase (P < 0.05) alkaline phosphatase from homogenates of liver and kidney tissues of the tested doses but there was no significant difference (P > 0.05) in alkaline phosphatase from rat serum

    Conrad O. Connie Orr Interview, June 14, 1984

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    Conrad Orr talks about his time working as a smokejumper from 1953 until 1958. He describes the training, including the types of injuries jumpers could receive, working on fires and project work, and the equipment smokejumpers used at that time. Orr also describes the dedication of the Aerial Fire Depot in Missoula, Montana, in 1954.https://scholarworks.umt.edu/smokejumpers/1082/thumbnail.jp
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