scholarly journals Genetics of Host Specificity in Epichloë typhina

1997 ◽  
Vol 87 (6) ◽  
pp. 599-605 ◽  
Author(s):  
Kuang-Ren Chung ◽  
Walter Hollin ◽  
Malcolm R. Siegel ◽  
Christopher L. Schardl
Keyword(s):  
Host Specificity ◽  
Perennial Ryegrass ◽  
High Efficiency ◽  
Rank Correlation ◽  
Significant Negative Correlation ◽  
Infection Frequency ◽  
Low Frequencies ◽  
Wide Range ◽  
Epichloë Typhina ◽  
Seedling Infection

Epichloë typhina perennially and systemically infects grass plants, causing choke disease in which maturation of host inflorescences is suppressed. In seedling-inoculation tests, isolate E8 from perennial ryegrass established and maintained infection in this host but not in orchardgrass. In contrast, isolates E469, E2466, and E2467 from orchardgrass varied in infection frequency and stability in orchardgrass, but all were unable to establish stable infections in perennial ryegrass. To investigate the genetics of host specificity, isolate E8 was crossed with each of the isolates from orchardgrass. Seedlings of parental host species were inoculated with F1 progeny, and the frequencies of seedling infection and stability in adult plants were assessed. In the E8 × E2466 cross, the F1 progeny exhibited a wide range of infection frequency and stability in each parental host. In crosses E8 × E469 and E8 × E2467, where the orchardgrass-derived parents infected 5 to 13% of inoculated perennial ryegrass seedlings, the distributions of infection frequencies for the F1 progeny wereskewed toward levels comparable to that of the parent from perennial ryegrass. In all crosses, most progeny had low frequencies of infection in orchardgrass. However, transgression was evident in a cross of E8 with E469, an isolate that infected orchardgrass seedlings at a low frequency (2 to 3%). The E8 × E469 cross had a few F1 progeny that infected orchardgrass at high efficiency (up to 81%). A Spearman rank correlation applied to the E8 × E2466 progeny indicated a significant negative correlation between infection frequencies in perennial ryegrass and orchardgrass. Also, there was a significant correlation of infection frequency and stability in perennial ryegrass but not in orchardgrass. To test whether only a few genes governed infection frequency in perennial ryegrass, an E8 × E2466 F1 progeny (designated E386.04), which had intermediate compatibility with this host, was backcrossed to E8. The progeny of this backcross exhibited a distribution of infection frequencies in perennial ryegrass between that of E386.04 and the backcross parent, suggesting that multiple genes may determine compatibility at the seedling infection stage. The results of these experiments indicated multiple genetic determinants of compatibility or incompatibility with each host, with intermediate or high heritability.

scholarly journals Increase the Efficiency of an Induction Motor Feed from Inverter for Low Frequencies by Combining Design and Control Improvements

Energies ◽  
2022 ◽  
Vol 15 (2) ◽  
pp. 530
Author(s):  
Maria Dems ◽  
Krzysztof Komeza ◽  
Jacek Szulakowski ◽  
Witold Kubiak
Keyword(s):  
Energy Savings ◽  
High Efficiency ◽  
Open Loop ◽  
Design Parameters ◽  
Optimal Size ◽  
Low Frequencies ◽  
Field Weakening ◽  
Speed Regulation ◽  
Wide Range ◽  
And Control

Speed-controlled induction motors have the most significant potential for energy savings. The greatest problems with obtaining high efficiency occur in motors with a wide range of rotational speed regulation, as in the motors for driving industrial washing machines under consideration. While for the highest speeds, the dominant phenomenon is at field weakening. The problem is obtaining the optimal size of the magnetic flux for low rotation speed to prevent excessive saturation increasing current, and reduction of efficiency. This problem is usually solved by selecting the appropriate control for an already built machine. The authors propose a combination of activities when designing the motor structure with the selection of proper control, which allows for high efficiency. Since the drive does not require precise speed control or obtaining the required dynamics, it was possible to use an inexpensive control in an open loop, avoiding the cost of transmitters. Furthermore, the number of design parameters that are subject to change is significantly limited by technological factors and the available space in the washing machine. Proper parameter selection was made using a peripheral method assisted by field-circuit simulations. The proposed approach can be used in designing structures and selecting motors controls for other applications.

Evaluation of the clot burden score (cbs) for acute ischemic stroke (ais) in intent-to-treat patients.

2019 ◽  
Vol 1 (1) ◽  
pp. 11-15 ◽  
Author(s):  
Sarah Yaziz ◽  
Ahmad Sobri Muda ◽  
Wan Asyraf Wan Zaidi ◽  
Nik Azuan Nik Ismail
Keyword(s):  
Ischemic Stroke ◽  
Clinical Outcome ◽  
Acute Ischemic Stroke ◽  
Predictive Value ◽  
Area Under The Curve ◽  
Rank Correlation ◽  
Treatment Decision ◽  
Roc Curves ◽  
Significant Negative Correlation ◽  
Clot Burden

Background : The clot burden score (CBS) is a scoring system used in acute ischemic stroke (AIS) to predict patient outcome and guide treatment decision. However, CBS is not routinely practiced in many institutions. This study aimed to investigate the feasibility of CBS as a relevant predictor of good clinical outcome in AIS cases. Methods:  A retrospective data collection and review of AIS patients in a teaching hospital was done from June 2010 until June 2015. Patients were selected following the inclusion and exclusion criteria. These patients were followed up after 90 days of discharge. The Modified Rankin scale (mRS) was used to assess their outcome (functional status). Linear regression Spearman Rank correlation was performed between the CBS and mRS. The quality performance of the correlations was evaluated using Receiver operating characteristic (ROC) curves. Results: A total of 89 patients with AIS were analysed, 67.4% (n=60) male and 32.6% (n=29) female. Twenty-nine (29) patients (33.7%) had a CBS ?6, 6 patients (6.7%) had CBS <6, while 53 patients (59.6%) were deemed clot free. Ninety (90) days post insult, clinical assessment showed that 57 (67.6%) patients were functionally independent, 27 (30.3%) patients functionally dependent, and 5 (5.6%) patients were deceased. Data analysis reported a significant negative correlation (r= -0.611, p<0.001). ROC curves analysis showed an area under the curve of 0.81 at the cut-off point of 6.5. This showed that a CBS of more than 6 predicted a good mRS clinical outcome in AIS patients; with sensitivity of 98.2%, specificity of 53.1%, positive predictive value (PPV) of 76%, and negative predictive value (NPV) of 21%. Conclusion: CBS is a useful additional variable for the management of AIS cases, and should be incorporated into the routine radiological reporting for acute ischemic stroke (AIS) cases.

USE OF CELL AND MOLECULAR GENETIC MANIPULATION TO IMPROVE PASTURE PLANTS

1988 ◽  
pp. 67-72
Author(s):  
D.W.R. White
Keyword(s):  
Cell Culture ◽  
Perennial Ryegrass ◽  
White Clover ◽  
Nutritional Quality ◽  
Rust Resistance ◽  
Herbicide Tolerance ◽  
Pest Resistance ◽  
Crown Rust ◽  
Wide Range ◽  
Pasture Plants

Cell culture and genetic engineering techniques can be used to develop improved pasture plants. To utilise these methods we have developed procedures for regenerating plants from tissue cultures of perennial ryegrass and white clover. In both, the plant genotype influences regeneration capacity. There was significant genetic variation among regenerated perennial ryegrass plants in a wide range of characteristics. Most of the regenerants were resIstant to crown rust and this trait was highly heritable. This rust resistance is being used to breed a new ryegrass cultivar. A system for introducing cloned genes into white clover is described. This capability is bemg used to incorporate genes with the potential to improve nutritional quality and pest resistance. Other possibilities for engineering genetic improvements in white clover, genes conferring herbicide tolerance and resistance to white clover mosaic virus, are briefly outlined. Keywords: Lolium perenne, Trifolium repens, cell culture, somaclonal variation, crown rust resistance, transformation, cloned genes, nutritional quality, proteinase inhibitors, Bt toxins, pest resistance, WCMV viral cross-protection, herbicide tolerance, Agrobacterium, Bacillus thuringenisis.

Synthesis of Elaborate Benzofuran-2-Carboxamide Derivatives Through a Combination of 8-Aminoquinoline Directed C–H Arylations and Transamidations

2019 ◽  
Author(s):  
Michael Oschmann ◽  
Linus Johansson Holm ◽  
Oscar Verho
Keyword(s):  
Small Molecule ◽  
High Efficiency ◽  
Synthetic Strategy ◽  
Small Molecule Screening ◽  
Physiological Properties ◽  
Wide Range ◽  
Directing Group ◽  
Synthetic Sequence

Benzofurans are everywhere in nature and they have been extensively studied by medicinal chemists over the years because of their chemotherapeutic and physiological properties. Herein, we describe a strategy that can be used to access elaborate benzo-2-carboxamide derivatives, which involves a synthetic sequence of 8-aminoquinoline directed C–H arylations followed by transamidations. For the directed C–H arylations, Pd catalysis was used to install a wide range of aryl and heteroaryl substituents at the C3 position of the benzofuran scaffold in high efficiency. Directing group cleavage and further diversification of the C3-arylated benzofuran products were then achieved in a single synthetic operation through the utilization of a two-step transamidation protocol. By bocylating the 8-aminoquinoline amide moiety of these products, it proved possible to activate them towards aminolysis with different amine nucleophiles. Interestingly, this aminolysis reaction was found to proceed efficiently without the need of any additional catalyst or additive. Given the high efficiency and modularity of this synthetic strategy, it constitute a very attractive approach for generating structurally-diverse collections of benzofuran derivatives for small molecule screening.

To the 70th anniversary of World Meteorological Organization. Scientific and technical cooperation of Hydrometeorological Center of the USSR/Russia in the Programs of World Meteorological Organization

2020 ◽  
pp. 117-138
Author(s):  
S.V. Borshch ◽  
◽  
R.M. Vil’fand ◽  
D.B. Kiktev ◽  
V.M. Khan ◽  
...  
Keyword(s):  
Environmental Monitoring ◽  
High Efficiency ◽  
World Meteorological Organization ◽  
70Th Anniversary ◽  
Technical Level ◽  
Technical Cooperation ◽  
Wide Range

The paper presents the summary and results of long-term and multi-faceted experience of international scientific and technical cooperation of Hydrometeorological Center of Russia in the field of hydrometeorology and environmental monitoring within the framework of WMO programs, which indicates its high efficiency in performing a wide range of works at a high scientific and technical level. Keywords: World Meteorological Organization, major WMO programs, representatives of Hydrometeorological Center of Russia in WMO

Integrated Design and Multi-Objective Optimization of a Single Stage Heat-Pump Turbocompressor

2013 ◽  
Author(s):  
J. Schiffmann
Keyword(s):  
Design Optimization ◽  
High Efficiency ◽  
Integrated Design ◽  
Heat Pumps ◽  
Small Scale ◽  
Multi Objective Optimization ◽  
Design Constraints ◽  
Multi Objective ◽  
Wide Range ◽  
Standard Design

Small scale turbomachines in domestic heat pumps reach high efficiency and provide oil-free solutions which improve heat-exchanger performance and offer major advantages in the design of advanced thermodynamic cycles. An appropriate turbocompressor for domestic air based heat pumps requires the ability to operate on a wide range of inlet pressure, pressure ratios and mass flows, confronting the designer with the necessity to compromise between range and efficiency. Further the design of small-scale direct driven turbomachines is a complex and interdisciplinary task. Textbook design procedures propose to split such systems into subcomponents and to design and optimize each element individually. This common procedure, however, tends to neglect the interactions between the different components leading to suboptimal solutions. The authors propose an approach based on the integrated philosophy for designing and optimizing gas bearing supported, direct driven turbocompressors for applications with challenging requirements with regards to operation range and efficiency. Using previously validated reduced order models for the different components an integrated model of the compressor is implemented and the optimum system found via multi-objective optimization. It is shown that compared to standard design procedure the integrated approach yields an increase of the seasonal compressor efficiency of more than 12 points. Further a design optimization based sensitivity analysis allows to investigate the influence of design constraints determined prior to optimization such as impeller surface roughness, rotor material and impeller force. A relaxation of these constrains yields additional room for improvement. Reduced impeller force improves efficiency due to a smaller thrust bearing mainly, whereas a lighter rotor material improves rotordynamic performance. A hydraulically smoother impeller surface improves the overall efficiency considerably by reducing aerodynamic losses. A combination of the relaxation of the 3 design constraints yields an additional improvement of 6 points compared to the original optimization process. The integrated design and optimization procedure implemented in the case of a complex design problem thus clearly shows its advantages compared to traditional design methods by allowing a truly exhaustive search for optimum solutions throughout the complete design space. It can be used for both design optimization and for design analysis.

scholarly journals Low Power Cusped Field Thruster Developed for the Space-Borne Gravitational Wave Detection Mission in China

2021 ◽  
Vol 11 (14) ◽  
pp. 6549
Author(s):  
Hui Liu ◽  
Ming Zeng ◽  
Xiang Niu ◽  
Hongyan Huang ◽  
Daren Yu
Keyword(s):  
Low Power ◽  
Gravitational Wave ◽  
Attitude Control ◽  
High Efficiency ◽  
Experimental Investigations ◽  
Attitude Control System ◽  
Gravitational Wave Detection ◽  
Wave Detection ◽  
Wide Range ◽  
Institute Of Technology

The microthruster is the crucial device of the drag-free attitude control system, essential for the space-borne gravitational wave detection mission. The cusped field thruster (also called the High Efficiency Multistage Plasma Thruster) becomes one of the candidate thrusters for the mission due to its low complexity and potential long life over a wide range of thrust. However, the prescribed minimum of thrust and thrust noise are considerable obstacles to downscaling works on cusped field thrusters. This article reviews the development of the low power cusped field thruster at the Harbin Institute of Technology since 2012, including the design of prototypes, experimental investigations and simulation studies. Progress has been made on the downscaling of cusped field thrusters, and a new concept of microwave discharge cusped field thruster has been introduced.

scholarly journals A general approach to high-efficiency perovskite solar cells by any antisolvent

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Alexander D. Taylor ◽  
Qing Sun ◽  
Katelyn P. Goetz ◽  
Qingzhi An ◽  
Tim Schramm ◽  
...  
Keyword(s):  
Solar Cells ◽  
High Efficiency ◽  
Perovskite Solar Cells ◽  
Precursor Solution ◽  
Microstructural Characterization ◽  
Application Rate ◽  
Perovskite Layer ◽  
Highly Efficient ◽  
Application Procedure ◽  
Wide Range

AbstractDeposition of perovskite films by antisolvent engineering is a highly common method employed in perovskite photovoltaics research. Herein, we report on a general method that allows for the fabrication of highly efficient perovskite solar cells by any antisolvent via manipulation of the antisolvent application rate. Through detailed structural, compositional, and microstructural characterization of perovskite layers fabricated by 14 different antisolvents, we identify two key factors that influence the quality of the perovskite layer: the solubility of the organic precursors in the antisolvent and its miscibility with the host solvent(s) of the perovskite precursor solution, which combine to produce rate-dependent behavior during the antisolvent application step. Leveraging this, we produce devices with power conversion efficiencies (PCEs) that exceed 21% using a wide range of antisolvents. Moreover, we demonstrate that employing the optimal antisolvent application procedure allows for highly efficient solar cells to be fabricated from a broad range of precursor stoichiometries.

scholarly journals Octane Index Applicability over the Pressure-Temperature Domain

Energies ◽  
2021 ◽  
Vol 14 (3) ◽  
pp. 607
Author(s):  
Tommy R. Powell ◽  
James P. Szybist ◽  
Flavio Dal Forno Chuahy ◽  
Scott J. Curran ◽  
John Mengwasser ◽  
...  
Keyword(s):  
High Efficiency ◽  
National Laboratory ◽  
Operating Conditions ◽  
Dominant Factor ◽  
Compression Ignition ◽  
Oak Ridge ◽  
Operating Modes ◽  
Wide Range ◽  
Thermodynamic Conditions ◽  
Si Engines

Modern boosted spark-ignition (SI) engines and emerging advanced compression ignition (ACI) engines operate under conditions that deviate substantially from the conditions of conventional autoignition metrics, namely the research and motor octane numbers (RON and MON). The octane index (OI) is an emerging autoignition metric based on RON and MON which was developed to better describe fuel knock resistance over a broader range of engine conditions. Prior research at Oak Ridge National Laboratory (ORNL) identified that OI performs reasonably well under stoichiometric boosted conditions, but inconsistencies exist in the ability of OI to predict autoignition behavior under ACI strategies. Instead, the autoignition behavior under ACI operation was found to correlate more closely to fuel composition, suggesting fuel chemistry differences that are insensitive to the conditions of the RON and MON tests may become the dominant factor under these high efficiency operating conditions. This investigation builds on earlier work to study autoignition behavior over six pressure-temperature (PT) trajectories that correspond to a wide range of operating conditions, including boosted SI operation, partial fuel stratification (PFS), and spark-assisted compression ignition (SACI). A total of 12 different fuels were investigated, including the Co-Optima core fuels and five fuels that represent refinery-relevant blending streams. It was found that, for the ACI operating modes investigated here, the low temperature reactions dominate reactivity, similar to boosted SI operating conditions because their PT trajectories lay close to the RON trajectory. Additionally, the OI metric was found to adequately predict autoignition resistance over the PT domain, for the ACI conditions investigated here, and for fuels from different chemical families. This finding is in contrast with the prior study using a different type of ACI operation with different thermodynamic conditions, specifically a significantly higher temperature at the start of compression, illustrating that fuel response depends highly on the ACI strategy being used.

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