scholarly journals Evaluation of Tactics for Managing Resistance of Venturia inaequalis to Sterol Demethylation Inhibitors

Plant Disease ◽  
1999 ◽  
Vol 83 (9) ◽  
pp. 857-863 ◽  
Author(s):  
Wolfram Köller ◽  
W. F. Wilcox
Keyword(s):  
Venturia Inaequalis ◽  
Apple Scab ◽  
Run Off ◽  
Equivalent Control ◽  
Sterol Demethylation Inhibitors ◽  
The Individual ◽  
And Control ◽  
The Impact ◽  
Low Rate ◽  
Selection Of

The impact on the selection and control of subpopulations of V. inaequalis resistant to the sterol demethylation inhibitor (DMI) fenarimol or to dodine were evaluated with respect to several tactics of apple scab control. Experiments were conducted in an experimental orchard with elevated levels of DMI and dodine resistance over a period of three consecutive seasons. The DMI-resistant subpopulation was poorly (14%) controlled at a fenarimol rate of 15 mg/liter (sprayed to run-off), whereas control was significantly improved (54%) at twice that rate. Mancozeb mixed with the low rate of fenarimol also improved the control of DMI-resistant isolates, but the improvement was due to the indiscriminate control of both the DMI-sensitive and -resistant populations provided by mancozeb. The selection of fenarimol-resistant isolates resulting from poor control of the resistant subpopulation by the low rate of fenarimol was equivalent whether fenarimol was applied singly or in mixture with mancozeb. Consequently, the use of high DMI rates in mixture with a protective fungicide is expected to delay the build-up of resistant subpopulations by limiting their increase through two separate principles of control. For dodine in mixture with fenarimol, it was found that each mixing partner applied alone selected both fe-narimol- and dodine-resistant isolates. This selection pattern was partly explained by the possibility that one of the multiple genes underlying fenarimol and dodine resistance confers resistance to both fungicides, in addition to the selection of double-resistant isolates. Regardless, a mixture of fenarimol with dodine each employed at a low rate controlled both the fenarimol-and the dodine-resistant subpopulation at least as effectively as the individual components at twice their mixture rate, and an accelerated selection of double-resistant isolates was not detected. In commercial orchard trials, mixtures of DMIs with either a protective fungicide or with dodine provided equivalent control even when levels of DMI resistance, dodine resistance, or both were moderately elevated. With the exception of orchards with high levels of DMI or dodine resistance, dodine might be an alternative to protective fungicides as a mixing partner with DMIs.

scholarly journals Evidence for the Predisposition of Fungicide-Resistant Isolates of Venturia inaequalis to a Preferential Selection for Resistance to Other Fungicides

2001 ◽  
Vol 91 (8) ◽  
pp. 776-781 ◽  
Author(s):  
Wolfram Köller ◽  
W. F. Wilcox
Keyword(s):  
Fungicide Resistance ◽  
Venturia Inaequalis ◽  
Apple Scab ◽  
The United States ◽  
Cross Resistance ◽  
Resistance Development ◽  
Flexible Response ◽  
Sterol Demethylation Inhibitors ◽  
Selection For ◽  
Selection Of

In the United States, populations of the apple scab pathogen Venturia inaequalis have progressed through three consecutive rounds of fungicide resistance development, first to dodine, then to the benzimidazoles, and most recently to the sterol demethylation inhibitors (DMIs). Analysis of extensive monitoring data have to date provided no indication of detectable cross-resistance or partial cross-resistance of V. inaequalis populations to the three unrelated classes of fungicides prior to the selection of resistant subpopulations. However, in this study, resistance to both benomyl and DMIs developed to significantly higher frequencies within the previously established dodine-resistant population than in the population sensitive to dodine. Accelerated selection of phenotypes double resistant to dodine and the DMI fenarimol was apparent over the course of distinct seasons of apple scab management with either dodine or fenarimol. The data provide evidence for an accelerated speed of resistance development among phenotypes of V. inaequalis already resistant to an unrelated fungicide. This finding represents a departure from the previous model, which assumed entirely independent rounds of resistance developments. The data indicate that phenotypes of V. inaequalis might not only be selected for the trait of fungicide resistance but also for traits allowing a more flexible response to changes in the environment where they compete.

scholarly journals Molecular Markers for the Scab Resistance (Vf) Region in Apple

1998 ◽  
Vol 123 (6) ◽  
pp. 992-996 ◽  
Author(s):  
Minou Hemmat ◽  
Norman F. Weeden ◽  
Herb S. Aldwinckle ◽  
Susan K. Brown
Keyword(s):  
Rapd Markers ◽  
Bulked Segregant Analysis ◽  
Venturia Inaequalis ◽  
Apple Scab ◽  
Scab Resistance ◽  
Resistant Plant ◽  
Tight Linkage ◽  
Test Population ◽  
Rate Selection ◽  
Selection Of

Bulked segregant analysis was used to identify RAPD markers that display tight linkage to the Vf gene in apple (Malus sp.) that confers resistance to five races of apple scab [Venturia inaequalis (Cke.) Wint.]. We identified several new RAPD markers linked to Vf. The most tightly linked marker in the test population, S52500, was cloned and sequenced. A linkage map of the Vf region was developed using these markers, RAPD markers previously described by other laboratories, and the isozyme locus Pgm-1. An assay was developed for Vf by multiplexing the two markers closely flanking the Vf locus. This assay has a theoretical `escape' value (discarding a resistant plant) of 3% and an error rate (selection of a susceptible plant) of 0.02%.

scholarly journals Localization of Vehicle Back-Up Alarms by Users of Level-Dependent Hearing Protectors under Industrial Noise Conditions Generated at a Forge

2019 ◽  
Vol 16 (3) ◽  
pp. 394 ◽  
Author(s):  
Rafal Mlynski ◽  
Emil Kozlowski
Keyword(s):  
Auditory Information ◽  
Danger Signal ◽  
Passive Mode ◽  
Specific Level ◽  
Alarm Signal ◽  
Hearing Protectors ◽  
Continuous Noise ◽  
The Individual ◽  
The Impact ◽  
Selection Of

The use of hearing protectors in various noisy workplaces is often necessary. For safety reasons, auditory information may be required to correctly localize the direction of an auditory danger signal. The purpose of this study was to verify if the selection of a specific level-dependent hearing protector may be important for the ability to localize a vehicle back-up alarm signal. The laboratory conditions reflected industrial conditions, under which an impulse noise was emitted against a background of continuous noise. A passive mode and a level-dependent mode (maximum and incomplete amplification) were considered. Four different models of level-dependent earmuffs and one model of level-dependent earplugs were included in the tests. The tests enabled differentiation between the individual hearing protectors. The use of earplugs in level-dependent mode did not significantly affect the ability to correctly localize the back-up alarm signal. For the earmuffs, the global assessment of the impact of a mode change revealed that, depending on the model of the earmuffs, the impact may be insignificant, but may also result in considerable impairment of the ability to localize the back-up alarm signal.

scholarly journals Development of an individual-based model for polioviruses: implications of the selection of network type and outcome metrics

2010 ◽  
Vol 139 (6) ◽  
pp. 836-848 ◽  
Author(s):  
H. RAHMANDAD ◽  
K. HU ◽  
R. J. DUINTJER TEBBENS ◽  
K. M. THOMPSON
Keyword(s):  
Network Structure ◽  
Critical Role ◽  
State Transitions ◽  
Different Types ◽  
Support Policy ◽  
The Individual ◽  
The Impact ◽  
Potential Use ◽  
Selection Of ◽  
Outcome Metrics

SUMMARYWe developed an individual-based (IB) model to explore the stochastic attributes of state transitions, the heterogeneity of the individual interactions, and the impact of different network structure choices on the poliovirus transmission process in the context of understanding the dynamics of outbreaks. We used a previously published differential equation-based model to develop the IB model and inputs. To explore the impact of different types of networks, we implemented a total of 26 variations of six different network structures in the IB model. We found that the choice of network structure plays a critical role in the model estimates of cases and the dynamics of outbreaks. This study provides insights about the potential use of an IB model to support policy analyses related to managing the risks of polioviruses and shows the importance of assumptions about network structure.

scholarly journals Integrated wind farm layout and control optimization

2020 ◽  
Author(s):  
Mads M. Pedersen ◽  
Gunner C. Larsen
Keyword(s):  
Wind Speed ◽  
Wind Turbine ◽  
Wind Farm ◽  
Design Space ◽  
Wind Farm Layout ◽  
Control Optimization ◽  
Mean Wind Speed ◽  
The Individual ◽  
And Control ◽  
Selection Of

Abstract. Design of an optimal wind farm topology and wind farm control scheduling depends on the chosen metric. The objective of this paper is to investigate the influence of optimal wind farm control on the optimal wind farm layout in terms of power production. A successful fulfilment of this goal requires: 1) an accurate and fast flow model; 2) selection of the minimum set of design parameters that rules the problem; and 3) selection of an optimization algorithm with good scaling properties. For control of the individual wind farm turbines, the two most obvious strategies are wake steering based on active wind turbine yaw control and wind turbine derating. The present investigation is a priori limited to wind turbine derating. A high-speed linearized CFD RANS solver models the flow field and the crucial wind turbine wake interactions inside the wind farm. The actuator disk method is used to model the wind turbines, and utilizing an aerodynamic model, the design space of the optimization problem is reduced to only three variables per turbine – two geometric and one carefully selected variable specifying the individual wind turbine derating setting for each mean wind speed and direction. The full design space spanned by these (2N + Nd Ns N) parameters, where N is the number of wind farm turbines, Nd is the number of direction bins, and Ns is the number of mean wind speed bins. This design space is decomposed in two subsets, which in turn define a nested set of optimization problems to achieve the fastest possible optimization procedure. Following a simplistic sanity check of the platform functionality regarding wind farm layout and control optimization, the capabilities of the developed optimization platform is demonstrated on the Swedish offshore wind farm. For this particular wind farm, the analysis demonstrates that the expected annual energy production can be increased by 4 % by integrating the wind farm control in the design of the wind farm layout, which is 1.2 % higher than what is achieved by optimizing the layout only.

scholarly journals Integrated wind farm layout and control optimization

2020 ◽  
Vol 5 (4) ◽  
pp. 1551-1566
Author(s):  
Mads M. Pedersen ◽  
Gunner C. Larsen
Keyword(s):  
Wind Turbine ◽  
Wind Farm ◽  
Design Space ◽  
Wind Farm Layout ◽  
Control Optimization ◽  
Mean Wind Speed ◽  
The Individual ◽  
Full Design ◽  
And Control ◽  
Selection Of

Abstract. The objective of this paper is to investigate the joint optimization of wind farm layout and wind farm control in terms of power production. A successful fulfilment of this goal requires the following: (1) an accurate and fast flow model, (2) selection of the minimum set of design parameters that rules or governs the problem, and (3) selection of an optimization algorithm with good scaling properties. For control of the individual wind farm turbines with the aim of wind farm production optimization, the two most obvious strategies are wake steering based on active wind turbine yaw control and wind turbine derating. The present investigation is limited to wind turbine derating. A high-speed linearized computational fluid dynamics (CFD) Reynolds-averaged Navier–Stokes (RANS) solver models the flow field and the crucial wind turbine wake interactions inside the wind farm. The actuator disc method is used to model the wind turbines, and utilizing an aerodynamic model, the design space of the optimization problem is reduced to only three variables per turbine – two geometric and one carefully selected variable specifying the individual wind turbine derating setting for each mean wind speed and direction. The full design space is spanned by these (2N+NdNsN) parameters, where N is the number of wind farm turbines, Nd is the number of direction bins, and Ns is the number of mean wind speed bins. This design space is decomposed into two subsets, which in turn define a nested set of optimization problems to achieve a significantly faster optimization procedure compared to a direct optimization based on the full design space. Following a simplistic sanity check of the platform functionality regarding wind farm layout and control optimization, the capability of the developed optimization platform is demonstrated on a Swedish offshore wind farm. For this particular wind farm, the analysis demonstrates that the expected annual energy production can be increased by 4 % by integrating the wind farm control into the design of the wind farm layout, which is 1.2 % higher than what is achieved by optimizing the layout only.

scholarly journals Development of an Automated Pain Facial Expression Detection System for Sheep (Ovis Aries)

Animals ◽  
2019 ◽  
Vol 9 (4) ◽  
pp. 196 ◽  
Author(s):  
Krista McLennan ◽  
Marwa Mahmoud
Keyword(s):  
Facial Expression ◽  
Detection System ◽  
Ovis Aries ◽  
Expression Recognition ◽  
Use Of Technology ◽  
Assessment And Treatment ◽  
The Individual ◽  
Individual Farm ◽  
And Control ◽  
The Impact

The use of technology to optimize the production and management of each individual animal is becoming key to good farming. There is a need for the real-time systematic detection and control of disease in animals in order to limit the impact on animal welfare and food supply. Diseases such as footrot and mastitis cause significant pain in sheep, and so early detection is vital to ensuring effective treatment and preventing the spread across the flock. Facial expression scoring to assess pain in humans and non-humans is now well utilized, and the Sheep Pain Facial Expression Scale (SPFES) is a tool that can reliably detect pain in this species. The SPFES currently requires manual scoring, leaving it open to observer bias, and it is also time-consuming. The ability of a computer to automatically detect and direct a producer as to where assessment and treatment are needed would increase the chances of controlling the spread of disease. It would also aid in the prevention of resistance across the individual, farm, and landscape at both national and international levels. In this paper, we present our framework for an integrated novel system based on techniques originally applied for human facial expression recognition that could be implemented at the farm level. To the authors’ knowledge, this is the first time that this technology has been applied to sheep to assess pain.

A Few Aspects on Lubricant Selection for Stepless Chain Coverters: Efficiency and Service Life

1992 ◽  
Author(s):  
G. Schönnenbeck
Keyword(s):  
Friction Coefficient ◽  
Service Life ◽  
Standardized Test ◽  
Test Methods ◽  
Long Term Stability ◽  
Friction Disk ◽  
The Individual ◽  
And Control ◽  
Selection Of

Abstract Stepless vehicle drives will assume their place next to automatic switching units throughout the world if they meet their expected fuel-saving potential. This necessitates optimizing the individual components of the CVT as regards their efficiency. The main source of losses are the hydraulic supply units and the losses which result specifically from non-positive transmission. In the case of stepless chain conveners, these result mainly from friction disk deformation. These losses account for 50 to 70 % of total CVT losses. Both loss components are influenced by the lubricant to a significantly greater extent than it would appear at first sight: In the case of fully-hydraulic clamping and control systems, the viscosity and its long-term stability determines the degree of leakage losses and therefore the size of the pump or pump combinations. This applies to pressure levels between 20 and 40 bar. This in turn is directly proportional to the hydraulic losses on the CVT. The friction coefficient of the lubricant determines the level of the necessary clamping forces. These are responsible for friction-disk deformation. Also of importance as far as the selection of lubricant is concerned is its influence on the CVT service life. The critical service life limits for chain converters are chain breakage (not the subject of this report) and evidence of wear, i.e. grey staining, sheave-grooving, pitting, scoring and rocker pin wear. Standardized test methods exist at P.I.V. for both wear manifestations and for the friction coefficient, these tests allowing a targeted selection of lubricants.

Multiple Realities of Women’s Work Experiences in Coaching and Athletic Management

2000 ◽  
Vol 9 (2) ◽  
pp. 1-26 ◽  
Author(s):  
Sue Inglis ◽  
Karen E. Danylchuk ◽  
Donna L. Pastore
Keyword(s):  
Women's Work ◽  
Work Experiences ◽  
Multiple Realities ◽  
Women’S Work ◽  
Power And Control ◽  
Management Positions ◽  
The Individual ◽  
And Control ◽  
The Impact ◽  
Athletic Management

This paper is an exploration of the multiple realities of women’s work experiences in coaching and athletic management positions. Eleven women who had previously coached or directed women’s athletics programs were interviewed using a semi-structured approach. Three general categories emerged from the data — Support, Gender Differences, and Change. The work experiences reflect problems the women encountered at work, how organizations can be empowering, and the impact empowered women can have on the social construction of work. Based upon the data, we suggest that the individual search for empowerment takes different forms, yet also acknowledges that systemic changes must take place in order to improve the work environment for women. These findings are significant because they validate women’s experiences and contribute to the understanding of work experiences of those who are underrepresented and often left out of key circles of power and control.

ST22 and ST239 MRSA duopoly in Singaporean hospitals: 2006–2010

2012 ◽  
Vol 141 (1) ◽  
pp. 153-157 ◽  
Author(s):  
J. TEO ◽  
T. Y. TAN ◽  
P. Y. HON ◽  
W. LEE ◽  
T. H. KOH ◽  
...  
Keyword(s):  
Variable Number Tandem Repeat ◽  
Variable Number ◽  
Small Subset ◽  
Monitoring And Control ◽  
Data Compilation ◽  
Laboratory Surveillance ◽  
Mrsa Infection ◽  
The Individual ◽  
And Control ◽  
Selection Of

SUMMARYSurveillance is integral for the monitoring and control of infectious diseases. We conducted prospective laboratory surveillance of methicillin-resistantStaphylococcus aureus(MRSA) in five Singaporean public-sector hospitals from 2006 to 2010, using WHONET 5.6 for data compilation and analysis. Molecular profiling using multilocus variable-number tandem-repeat analysis, staphylococcal cassette chromosomemecclassification and multilocus sequence typing was performed for a random selection of isolates. Our results showed overall stable rates of infection and bacteraemia, although there was significant variance among the individual hospitals, with MRSA rates increasing in two smaller hospitals and showing a trend towards decreasing in the two largest hospitals. The proportion of blood isolates that are EMRSA-15 (ST22-IV) continued to increase over time, slowly replacing the multi-resistant ST239-III. A new MRSA clone – ST45-IV – is now responsible for a small subset of hospital infections locally. More effort is required in Singaporean hospitals in order to reduce the rates of MRSA infection significantly.

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