Modeling Pauli measurements on graph states with nearest-neighbor classical communication

We propose a communication-assisted local-hidden-variable model that yields the correct outcome for the measurement of any product of Pauli operators on an arbitrary graph state, i.e., that yields the correct global correlation among the individual measurements in the Pauli product. Within this model, communication is restricted to a single round of message passing between adjacent nodes of the graph. We show that any model sharing some general properties with our own is incapable, for at least some graph states, of reproducing the expected correlations among all subsets of the individual measurements. The ability to reproduce all such correlations is found to depend on both the communication distance and the symmetries of the communication protocol.Comment: 9 pages, 2 figures. Version 2 significantly revised. Now includes a site-invariant protocol for linear chains and a proof that no limited communication protocol can correctly predict all quantum correlations for ring

Graphical description of the action of Clifford operators on stabilizer states

We introduce a graphical representation of stabilizer states and translate the action of Clifford operators on stabilizer states into graph operations on the corresponding stabilizer-state graphs. Our stabilizer graphs are constructed of solid and hollow nodes, with (undirected) edges between nodes and with loops and signs attached to individual nodes. We find that local Clifford transformations are completely described in terms of local complementation on nodes and along edges, loop complementation, and change of node type or sign. Additionally, we show that a small set of equivalence rules generates all graphs corresponding to a given stabilizer state; we do this by constructing an efficient procedure for testing the equality of any two stabilizer graphs.Comment: 14 pages, 8 figures. Version 2 contains significant changes. Submitted to PR

Restrictions on Transversal Encoded Quantum Gate Sets

Transversal gates play an important role in the theory of fault-tolerant quantum computation due to their simplicity and robustness to noise. By definition, transversal operators do not couple physical subsystems within the same code block. Consequently, such operators do not spread errors within code blocks and are, therefore, fault tolerant. Nonetheless, other methods of ensuring fault tolerance are required, as it is invariably the case that some encoded gates cannot be implemented transversally. This observation has led to a long-standing conjecture that transversal encoded gate sets cannot be universal. Here we show that the ability of a quantum code to detect an arbitrary error on any single physical subsystem is incompatible with the existence of a universal, transversal encoded gate set for the code.Comment: 4 pages, v2: minor change

Studies in the Geochronology and Geochemistry of the Transantarctic Mountains

This is the third annual progress report submitted by Institute of Polar Studies researchers to the National Science Foundation (Grant No. GA-898X) on the geochronology and geochemistry of rocks from the Transantarctic Mountains, Antarctica. The results reported in this report are preliminary in nature.National Science Foundation Grant GA-898

Comparison of an ultra-low volume (ULV) sprayer against a conventional sprayer, for foliar fertiliser and fungicide applications in turfgrass

Two field studies (I and II) at the University of Nebraska-Lincoln: John Seaton Anderson Turfgrass Research Facility near Mead, NE, USA, were conducted to determine if a new ultra-low volume (ULV) sprayer can apply foliar nutrient, growth regulator, and fungicide treatments, in a manner similar to that of a conventional sprayer. Treatments were applied over creeping bentgrass ‘L-93’ (Agrostis stolonifera L.) managed as a fairway at 561 l · ha−1 and 47 l · ha−1 with the conventional and ULV sprayer, respectfully. Data were collected for chlorophyll content with a chlorophyll meter, and for the normalised difference vegetation index (NDVI) with a turf colour meter. Each plot was harvested for biomass at 21 days after treatment. Study II compared the ULV sprayer and a conventional sprayer, for the control of brown patch (Rhizoctonia solani Kuhn) in creeping bentgrass. The treatments were propiconazole and azoxystrobin. Spray volume was 561 l · ha−1 for the conventional sprayer, and 19 l · ha−1 for the ULV sprayer. Statistical differences in turf quality or dry weight reductions between the conventional and ULV sprayer were not detected. Brown patch control was also similar between the two sprayers, but azoxystrobin provided better control than propiconazole. Even with a 30-fold decrease in application volume, the results indicated that the Kamterter ULV sprayer may be a useful and effective management option for foliar fertiliser and fungicide applications in turfgrass

Comparison of an ultra-low volume (ULV) sprayer against a conventional sprayer, for foliar fertiliser and fungicide applications in turfgrass

Two field studies (I and II) at the University of Nebraska-Lincoln: John Seaton Anderson Turfgrass Research Facility near Mead, NE, USA, were conducted to determine if a new ultra-low volume (ULV) sprayer can apply foliar nutrient, growth regulator, and fungicide treatments, in a manner similar to that of a conventional sprayer. Treatments were applied over creeping bentgrass ‘L-93’ (Agrostis stolonifera L.) managed as a fairway at 561 l · ha−1 and 47 l · ha−1 with the conventional and ULV sprayer, respectfully. Data were collected for chlorophyll content with a chlorophyll meter, and for the normalised difference vegetation index (NDVI) with a turf colour meter. Each plot was harvested for biomass at 21 days after treatment. Study II compared the ULV sprayer and a conventional sprayer, for the control of brown patch (Rhizoctonia solani Kuhn) in creeping bentgrass. The treatments were propiconazole and azoxystrobin. Spray volume was 561 l · ha−1 for the conventional sprayer, and 19 l · ha−1 for the ULV sprayer. Statistical differences in turf quality or dry weight reductions between the conventional and ULV sprayer were not detected. Brown patch control was also similar between the two sprayers, but azoxystrobin provided better control than propiconazole. Even with a 30-fold decrease in application volume, the results indicated that the Kamterter ULV sprayer may be a useful and effective management option for foliar fertiliser and fungicide applications in turfgrass

Integrating Interactive Web-Based Technology to Assess Adherence and Clinical Outcomes in Pediatric Sickle Cell Disease

Research indicates that the quality of the adherence assessment is one of the best predictors for improving clinical outcomes. Newer technologies represent an opportunity for developing high quality standardized assessments to assess clinical outcomes such as patient experience of care but have not been tested systematically in pediatric sickle cell disease (SCD). The goal of the current study was to pilot an interactive web-based tool, the Take-Charge Program, to assess adherence to clinic visits and hydroxyurea (HU), barriers to adherence, solutions to overcome these barriers, and clinical outcomes in 43 patients with SCD age 6–21 years. Results indicate that the web-based tool was successfully integrated into the clinical setting while maintaining high patient satisfaction (>90%). The tool provided data consistent with the medical record, staff report, and/or clinical lab data. Participants reported that forgetting and transportation were major barriers for adherence to both clinic attendance and HU. A greater number of self-reported barriers (P < .01) and older age (P < .05) were associated with poorer clinic attendance and HU adherence. In summary, the tool represents an innovative approach to integrate newer technology to assess adherence and clinical outcomes for pediatric patients with SCD

Chromosomal control of non-gliadin proteins from the 70% ethanol extract of wheat endosperm

The non-gliadin fraction of the 70% ethanol extracts of compensated nulli-tetrasomics and ditelosomics of Triticum aestivum cv. Chinese Spring has been analyzed by combined electrofocusing and electrophoresis. Seventeen of the 21 protein map components of the euploid have been ascribed to eight chromosomes: 4A, 3BS, 6BS, 7BS, 3D, 4D, 5D and 7DS. The relationship of the different map components with other proteins previously associated with the same chromosomes is discusse

Pre-anthesis ovary development determines genotypic differences in potential kernel weight in sorghum

Kernel weight is an important factor determining grain yield and nutritional quality in sorghum, yet the developmental processes underlying the genotypic differences in potential kernel weight remain unclear. The aim of this study was to determine the stage in development at which genetic effects on potential kernel weight were realized, and to investigate the developmental mechanisms by which potential kernel weight is controlled in sorghum. Kernel development was studied in two field experiments with five genotypes known to differ in kernel weight at maturity. Pre-fertilization floret and ovary development was examined and post-fertilization kernel-filling characteristics were analysed. Large kernels had a higher rate of kernel filling and contained more endosperm cells and starch granules than normal-sized kernels. Genotypic differences in kernel development appeared before stamen primordia initiation in the developing florets, with sessile spikelets of large-seeded genotypes having larger floret apical meristems than normal-seeded genotypes. At anthesis, the ovaries for large-sized kernels were larger in volume, with more cells per layer and more vascular bundles in the ovary wall. Across experiments and genotypes, there was a significant positive correlation between kernel dry weight at maturity and ovary volume at anthesis. Genotypic effects on meristem size, ovary volume, and kernel weight were all consistent with additive genetic control, suggesting that they were causally related. The pre-fertilization genetic control of kernel weight probably operated through the developing pericarp, which is derived from the ovary wall and potentially constrains kernel expansion