Tracking Vector Magnetograms with the Magnetic Induction Equation

The differential affine velocity estimator (DAVE) developed in Schuck (2006) for estimating velocities from line-of-sight magnetograms is modified to directly incorporate horizontal magnetic fields to produce a differential affine velocity estimator for vector magnetograms (DAVE4VM). The DAVE4VM's performance is demonstrated on the synthetic data from the anelastic pseudospectral ANMHD simulations that were used in the recent comparison of velocity inversion techniques by Welsch (2007). The DAVE4VM predicts roughly 95% of the helicity rate and 75% of the power transmitted through the simulation slice. Inter-comparison between DAVE4VM and DAVE and further analysis of the DAVE method demonstrates that line-of-sight tracking methods capture the shearing motion of magnetic footpoints but are insensitive to flux emergence -- the velocities determined from line-of-sight methods are more consistent with horizontal plasma velocities than with flux transport velocities. These results suggest that previous studies that rely on velocities determined from line-of-sight methods such as the DAVE or local correlation tracking may substantially misrepresent the total helicity rates and power through the photosphere.Comment: 30 pages, 13 figure

Propulsion System Choices and Their Implications

In defining a space vehicle architecture, the propulsion system and related subsystem choices will have a major influence on achieving the goals and objectives desired. There are many alternatives and the choices made must produce a system that meets the performance requirements, but at the same time also provide the greatest opportunity of reaching all of the required objectives. Recognizing the above, the SPST Functional Requirements subteam has drawn on the knowledge, expertise, and experience of its members, to develop insight that wiIJ effectively aid the architectural concept developer in making the appropriate choices consistent with the architecture goals. This data not only identifies many selected choices, but also, more importantly, presents the collective assessment of this subteam on the "pros" and the "cons" of these choices. The propulsion system choices with their pros and cons are presented in five major groups. A. System Integration Approach. Focused on the requirement for safety, reliability, dependability, maintainability, and low cost. B. Non-Chemical Propulsion. Focused on choice of propulsion type. C. Chemical Propulsion. Focused on propellant choice implications. D. Functional Integration. Focused on the degree of integration of the many propulsive and closely associated functions, and on the choice of the engine combustion power cycle. E. Thermal Management. Focused on propellant tank insulation and integration. Each of these groups is further broken down into subgroups, and at that level the consensus pros and cons are presented. The intended use of this paper is to provide a resource of focused material for architectural concept developers to use in designing new advanced systems including college design classes. It is also a possible source of input material for developing a model for designing and analyzing advanced concepts to help identify focused technology needs and their priorities

Semiclassical approach to discrete symmetries in quantum chaos

We use semiclassical methods to evaluate the spectral two-point correlation function of quantum chaotic systems with discrete geometrical symmetries. The energy spectra of these systems can be divided into subspectra that are associated to irreducible representations of the corresponding symmetry group. We show that for (spinless) time reversal invariant systems the statistics inside these subspectra depend on the type of irreducible representation. For real representations the spectral statistics agree with those of the Gaussian Orthogonal Ensemble (GOE) of Random Matrix Theory (RMT), whereas complex representations correspond to the Gaussian Unitary Ensemble (GUE). For systems without time reversal invariance all subspectra show GUE statistics. There are no correlations between non-degenerate subspectra. Our techniques generalize recent developments in the semiclassical approach to quantum chaos allowing one to obtain full agreement with the two-point correlation function predicted by RMT, including oscillatory contributions.Comment: 26 pages, 8 Figure

Chaotic maps and flows: Exact Riemann-Siegel lookalike for spectral fluctuations

To treat the spectral statistics of quantum maps and flows that are fully chaotic classically, we use the rigorous Riemann-Siegel lookalike available for the spectral determinant of unitary time evolution operators $F$. Concentrating on dynamics without time reversal invariance we get the exact two-point correlator of the spectral density for finite dimension $N$ of the matrix representative of $F$, as phenomenologically given by random matrix theory. In the limit $N\to\infty$ the correlator of the Gaussian unitary ensemble is recovered. Previously conjectured cancellations of contributions of pseudo-orbits with periods beyond half the Heisenberg time are shown to be implied by the Riemann-Siegel lookalike

Mitigating cyanobacterial harmful algal blooms in aquatic ecosystems impacted by climate change and anthropogenic nutrients

Mitigating the global expansion of cyanobacterial harmful blooms (CyanoHABs) is a major challenge facing researchers and resource managers. A variety of traditional (e.g., nutrient load reduction) and experimental (e.g., artificial mixing and flushing, omnivorous fish removal) approaches have been used to reduce bloom occurrences. Managers now face the additional effects of climate change on watershed hydrologic and nutrient loading dynamics, lake and estuary temperature, mixing regime, internal nutrient dynamics, and other factors. Those changes favor CyanoHABs over other phytoplankton and could influence the efficacy of control measures. Virtually all mitigation strategies are influenced by climate changes, which may require setting new nutrient input reduction targets and establishing nutrient-bloom thresholds for impacted waters. Physical-forcing mitigation techniques, such as flushing and artificial mixing, will need adjustments to deal with the ramifications of climate change. Here, we examine the suite of current mitigation strategies and the potential options for adapting and optimizing them in a world facing increasing human population pressure and climate change

Pharmacological assessment of the contribution of the arterial baroreflex to sympathetic discharge patterns in healthy humans

To study how changes in baroreceptor afferent activity affect patterns of sympathetic neural activation, we manipulated arterial blood pressure with intravenous nitroprusside (NTP) and phenylephrine (PE) and measured action potential (AP) patterns with wavelet-based methodology. We hypothesized that 1) baroreflex unloading (NTP) would increase firing of low-threshold axons and recruitment of latent axons and 2) baroreflex loading (PE) would decrease firing of low-threshold axons. Heart rate (HR, ECG), arterial blood pressure (BP, brachial catheter), and muscle sympathetic nerve activity (MSNA, microneurography of peroneal nerve) were measured at baseline and during steady-state systemic, intravenous NTP (0.5-1.2 µg·kg -1 ·min -1 , n = 13) or PE (0.2-1.0 µg·kg -1 ·min -1 , n = 9) infusion. BP decreased and HR and integrated MSNA increased with NTP (P \u3c 0.01). AP incidence (326 ± 66 to 579 ± 129 APs/100 heartbeats) and AP content per integrated burst (8 ± 1 to 11 ± 2 APs/burst) increased with NTP (P \u3c 0.05). The firing probability of low-threshold axons increased with NTP, and recruitment of high-threshold axons was observed (22 ± 3 to 24 ± 3 max cluster number, 9 ± 1 to 11 ± 1 clusters/burst; P \u3c 0.05). BP increased and HR and integrated MSNA decreased with PE (P \u3c 0.05). PE decreased AP incidence (406 ± 128 to 166 ± 42 APs/100 heartbeats) and resulted in fewer unique clusters (15 ± 2 to 9 ± 1 max cluster number, P \u3c 0.05); components of an integrated burst (APs or clusters per burst) were not altered (P \u3e 0.05). These data support a hierarchical pattern of sympathetic neural activation during manipulation of baroreceptor afferent activity, with rate coding of active neurons playing the predominant role and recruitment/derecruitment of higher-threshold units occurring with steady-state hypotensive stress. NEW & NOTEWORTHY To study how changes in baroreceptor afferent activity affect patterns of sympathetic neural activation, we manipulated arterial blood pressure with intravenous nitroprusside and phenylephrine and measured sympathetic outflow with wavelet-based methodology. Baroreflex unloading increased sympathetic activity by increasing firing probability of low-threshold axons (rate coding) and recruiting new populations of high-threshold axons. Baroreflex loading decreased sympathetic activity by decreasing the firing probability of larger axons (derecruitment); however, the components of an integrated burst were unaffected

Theoretical Insights into Vinyl Derivatives Adsorption on a Cu(100) Surface

This document is the Accepted Manuscript version of a Published Work that appeared in final form in The Journal of Physical Chemistry C, © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://pubs.acs.org/doi/abs/10.1021/acs.jpcc.8b06142Here, we present a thorough theoretical study of the adsorption of acrolein (ACO), acrylonitrile (ACN), and acrylamide (ACA) on Cu(100) surface. For this purpose, we have used the density functional theory, imposing periodic boundary conditions to have a correct description of the electronic band structure of the metal and including dispersion forces through two different schemes: the D2 method of Grimme and the vdW-DF. We have found several adsorption geometries. In all of them, the vinyl group together with the amide (in ACA), ciano (in ACN), and carbonyl (in ACO) groups, is highly involved. The highest adsorption energy is found for acrylamide, followed by acrolein and the lowest for acrylonitrile (depending on the level of theory employed ∼1.2, 1.0, and 0.9 eV, respectively). We show that a strong coupling between the π electronic system (both occupied and virtual orbitals) and the electronic levels of the metal is mainly responsible of the chemisorption. As a consequence, electronic density is transferred from the surface to the molecule, whose carbon atoms acquire a partial sp3 hybridization. Lone-pair orbitals of the cyano, amide, and carbonyl groups also play a role in the interaction. The simulations and following analysis allow to disentangle the nature of the interaction, which can be explained on the basis of a simple chemical picture: donation from the occupied lone pair and π orbitals of the molecule to the surface and backdonation from the surface to the π∗ orbital of the molecule (π-backbonding)This work was partially supported by the project CTQ2016-76061-P of the Spanish Ministerio de Economı́a y Competitividad (MINECO). F.A.G. acknowledges the FPI grant associated with the project CTQ2013-43698-P (MINECO). Financial support from the MINECO through the “Marı́a de Maeztu” Program for Units of Excellence in R&D (MDM-2014-0377) is also acknowledge

Small and mighty: adaptation of superphylum Patescibacteria to groundwater environment drives their genome simplicity.

BackgroundThe newly defined superphylum Patescibacteria such as Parcubacteria (OD1) and Microgenomates (OP11) has been found to be prevalent in groundwater, sediment, lake, and other aquifer environments. Recently increasing attention has been paid to this diverse superphylum including > 20 candidate phyla (a large part of the candidate phylum radiation, CPR) because it refreshed our view of the tree of life. However, adaptive traits contributing to its prevalence are still not well known.ResultsHere, we investigated the genomic features and metabolic pathways of Patescibacteria in groundwater through genome-resolved metagenomics analysis of > 600 Gbp sequence data. We observed that, while the members of Patescibacteria have reduced genomes (~ 1 Mbp) exclusively, functions essential to growth and reproduction such as genetic information processing were retained. Surprisingly, they have sharply reduced redundant and nonessential functions, including specific metabolic activities and stress response systems. The Patescibacteria have ultra-small cells and simplified membrane structures, including flagellar assembly, transporters, and two-component systems. Despite the lack of CRISPR viral defense, the bacteria may evade predation through deletion of common membrane phage receptors and other alternative strategies, which may explain the low representation of prophage proteins in their genomes and lack of CRISPR. By establishing the linkages between bacterial features and the groundwater environmental conditions, our results provide important insights into the functions and evolution of this CPR group.ConclusionsWe found that Patescibacteria has streamlined many functions while acquiring advantages such as avoiding phage invasion, to adapt to the groundwater environment. The unique features of small genome size, ultra-small cell size, and lacking CRISPR of this large lineage are bringing new understandings on life of Bacteria. Our results provide important insights into the mechanisms for adaptation of the superphylum in the groundwater environments, and demonstrate a case where less is more, and small is mighty

1994 turfgrass research report

Moss control on bentgrass greens evaluation / Jill Taylor -- Preemergent spotted spurge broadleaf weed control evaluation / William Pound and Renee Stewart -- Finale/Roundup herbicide demonstration evaluation / William Pound and Renee Stewart -- Turflon solvent evaluation / William Pound and Renee Stewart -- General turfgrass broadleaf weed control evaluation / William Pound and Renee Stewart -- Postemergence herbicide efficacy on crabgrass / John Street and Renee Stewart -- Preemergence herbicide efficacy on crabgrass / John Street, Jill Taylor and Renee Stewart -- Leaf spot control study / Joe Rimelspach, Karl Danneberger and Jill Taylor -- Dollar spot control study / Karl Danneberger, Joe Rimelspach and Jill Taylor -- Brown patch control study / Karl Danneberger, Joe Rimelspach and Jill Taylor -- Anthracnose control study / Karl Danneberger, Joe Rimelspach and Jill Taylor -- Summer patch control study / Joe Rimelspach, Karl Danneberger and Jill Taylor -- Yellow tuft control study / Karl Danneberger, Joe Rimelspach and Jill Taylor -- Red thread control study, Columbus / Joe Rimelspach, Karl Danneberger and Jill Taylor -- Red thread control study, Delaware / Joe Rimelspach, Bobby Joyner, Joe Green and Jerry Sullivan -- Susceptibility of bentgrass cultivars to Fore+ Aliette combinations / Karl Danneberger and Jill Taylor -- Suppression of turf diseases with biocontrol agent fortified compost-amended topdressings / Marcella Grebus, Carol Musselman, Joe Rimelspach and Harry Hoitink -- Evaluation of fungicides for resistance to dollar spot (Sclerotinia homoecmpa) on creeping bentgrass / Joe Rimelspach, Jill Taylor and Karl Danneberger -- Application of an insect growth regulator and insecticide on baits for control of ant mounds in turfgrass / David Shetlar, Harry Niemczyk and Kevin Power -- Application of insecticides for control of black turfgrass ataenius larvae in turfgrass / David Shetlar, Harry Niemczyk and Kevin Power -- Evaluation of biorationals and biologicals for control of black cutworm (Agrotis ipsilon Hufnagel) and sod webworm (Pyralidae, Crambinae) larvae in bentgrass, 1994 / David Shetlar, Harry Niemczyk and Kevin Power -- Evaluation of pyrethroids and other insecticides for control of black cutworm (Agrotis ipsilon Hufnagel) and sod webworm (Pyralidae, Crambinae) larvae in bentgrass, 1994 / David Shetlar, Harry Niemczyk and Kevin Power -- Surface and subsurface applied insecticides for control of white grubs in turfgrass / David Shetlar, Harry Niemczyk and Kevin Power -- Influence of application time on the efficacy of insect growth regulators for control of white grubs in turfgrass / David Shetlar, Harry Niemczyk and Kevin Power -- Subsurface placement of controlled release chlorpyrifos granules for extended control of Japanese beetle larvae in turfgrass: third report / Harry Niemczyk and David Shetlar -- Evaluation of Turplex 3 % EC for control of black cutworm larvae on the greens of Shadow Creek Golf Course, N. Las Vegas, Nevada / Harry Niemczyk -- Nitrogen Source and Rate effect on Kentucky bluegrass / John Street and Renee Stewart -- Polymer-coated nitrogen source effect on Kentucky bluegrass / John Street and Renee Stewart -- Evaluation of turfgrass species and cultivars for shade / Jill Taylor -- Regional low input sustainable turf study / Jill Taylor -- 1990 NTEP perennial ryegrass test / Jill Taylor -- 1994 NTEP perennial ryegrass test / Jill Taylor -- 1993 NTEP bentgrass test (fairway/tee) / Jill Taylor -- 1993 NTEP fineleaf fescue test / Jill Taylor -- Bermudagrass management study / John Street and Jill Taylor -- Duration of rolling as measured by ball roll / Karl Danneberger, Jill Taylor and Jobin Morrow -- Golf ball roll as influenced by soft spike and traditional metal spike golf shoes / Karl Danneberger and Jobin Morrow -- Primo/Banner interaction study / Bill Pound, Renee Stewart and Joe Rimelspach -- Primo growth regulator evaluation on creeping bentgrass / William Pound and Renee Stewart -- Restriction of arbitrary amplification fragments of Poa annua L. / Patty Sweeney and Karl Danneberge

Advanced Space Transportation Concepts and Propulsion Technologies for a New Delivery Paradigm

This paper describes Advanced Space Transportation Concepts and Propulsion Technologies for a New Delivery Paradigm. It builds on the work of the previous paper "Approach to an Affordable and Productive Space Transportation System". The scope includes both flight and ground system elements, and focuses on their compatibility and capability to achieve a technical solution that is operationally productive and also affordable. A clear and revolutionary approach, including advanced propulsion systems (advanced LOX rich booster engine concept having independent LOX and fuel cooling systems, thrust augmentation with LOX rich boost and fuel rich operation at altitude), improved vehicle concepts (autogeneous pressurization, turbo alternator for electric power during ascent, hot gases to purge system and keep moisture out), and ground delivery systems, was examined. Previous papers by the authors and other members of the Space Propulsion Synergy Team (SPST) focused on space flight system engineering methods, along with operationally efficient propulsion system concepts and technologies. This paper continues the previous work by exploring the propulsion technology aspects in more depth and how they may enable the vehicle designs from the previous paper. Subsequent papers will explore the vehicle design, the ground support system, and the operations aspects of the new delivery paradigm in greater detail