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Статті в журналах з теми "Highly regulated basins"

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Zaniolo, Marta, Matteo Giuliani, Andrea Francesco Castelletti, and Manuel Pulido-Velazquez. "Automatic design of basin-specific drought indexes for highly regulated water systems." Hydrology and Earth System Sciences 22, no. 4 (April 20, 2018): 2409–24. http://dx.doi.org/10.5194/hess-22-2409-2018.

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Abstract. Socio-economic costs of drought are progressively increasing worldwide due to undergoing alterations of hydro-meteorological regimes induced by climate change. Although drought management is largely studied in the literature, traditional drought indexes often fail at detecting critical events in highly regulated systems, where natural water availability is conditioned by the operation of water infrastructures such as dams, diversions, and pumping wells. Here, ad hoc index formulations are usually adopted based on empirical combinations of several, supposed-to-be significant, hydro-meteorological variables. These customized formulations, however, while effective in the design basin, can hardly be generalized and transferred to different contexts. In this study, we contribute FRIDA (FRamework for Index-based Drought Analysis), a novel framework for the automatic design of basin-customized drought indexes. In contrast to ad hoc empirical approaches, FRIDA is fully automated, generalizable, and portable across different basins. FRIDA builds an index representing a surrogate of the drought conditions of the basin, computed by combining all the relevant available information about the water circulating in the system identified by means of a feature extraction algorithm. We used the Wrapper for Quasi-Equally Informative Subset Selection (W-QEISS), which features a multi-objective evolutionary algorithm to find Pareto-efficient subsets of variables by maximizing the wrapper accuracy, minimizing the number of selected variables, and optimizing relevance and redundancy of the subset. The preferred variable subset is selected among the efficient solutions and used to formulate the final index according to alternative model structures. We apply FRIDA to the case study of the Jucar river basin (Spain), a drought-prone and highly regulated Mediterranean water resource system, where an advanced drought management plan relying on the formulation of an ad hoc “state index” is used for triggering drought management measures. The state index was constructed empirically with a trial-and-error process begun in the 1980s and finalized in 2007, guided by the experts from the Confederación Hidrográfica del Júcar (CHJ). Our results show that the automated variable selection outcomes align with CHJ's 25-year-long empirical refinement. In addition, the resultant FRIDA index outperforms the official State Index in terms of accuracy in reproducing the target variable and cardinality of the selected inputs set.
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Polo, María J., Albert Rovira, Darío García-Contreras, Eva Contreras, Agustín Millares, Cristina Aguilar, and Miguel A. Losada. "Reservoir impacts downstream in highly regulated river basins: the Ebro delta and the Guadalquivir estuary in Spain." Proceedings of the International Association of Hydrological Sciences 373 (May 12, 2016): 45–49. http://dx.doi.org/10.5194/piahs-373-45-2016.

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Abstract. Regulation by reservoirs affects both the freshwater regime and the sediment delivery at the area downstream, and may have a significant impact on water quality in the final transitional water bodies. Spain is one the countries with more water storage capacity by reservoirs in the world. Dense reservoir networks can be found in most of the hydrographic basins, especially in the central and southern regions. The spatial redistribution of the seasonal and annual water storage in reservoirs for irrigation and urban supply, mainly, has resulted in significant changes of water flow and sediment load regimes, together with a fostered development of soil and water uses, with environmental impacts downstream and higher vulnerability of these areas to the sea level rise and drought occurrence. This work shows these effects in the Guadalquivir and the Ebro River basins, two of the largest regulated areas in Spain. The results show a 71 % decrease of the annual freshwater input to the Guadalquivir River estuary during 1930–2014, an increase of 420 % of the irrigated area upstream the estuary, and suspended sediment loads up to 1000 % the initial levels. In the Ebro River delta, the annual water yield has decreased over a 30 % but, on the contrary, the big reservoirs are located in the main stream, and the sediment load has decreased a 99 %, resulting in a delta coastal regression up to 10 m per year and the massive presence of macrophytes in the lower river. Adaptive actions proposed to face these impacts in a sea level rise scenario are also analyzed.
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Paraguassú-Chaves, Carlos Alberto, Fabio Robson Casara Cavalcante, Gilmara Ferreira de Lima, Ana Maria Morais da Fonseca Cavalcante, Carla Dolezel Trindade, Simão Aznar Filho, Ruy Drummont Smith, Simão Dolezel Aznar, and Fabrício Moraes de Almeida. "Watershed Level Sustainable Development Index in Rondônia, Western Amazon." International Journal for Innovation Education and Research 10, no. 9 (September 1, 2022): 283–309. http://dx.doi.org/10.31686/ijier.vol10.iss9.3908.

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Objective: to build a sustainable development index for the river basins of Rondônia, using factor analysis as an analytical model. Method: factor analysis was used as a tool for building environmental, economic, social and institutional performance indices. The adapted FECAM classification scale was adopted to express the results achieved by each river basin. Results: The set of current sustainable performance indices for the Mamoré River watersheds (0.444) was considered a low index, although the best compared to other basins; the Madeira River (0.419, low index); the Guaporé River (0.378, low index); the Machado River (0.289, low index); the Jamari River (0.307, low index) and the Roosevelt River (0.227, low index). There has been a really insignificant improvement in the rates from 10 years ago. Conclusions: the factor analysis showed efficiency as a multivariate statistical method in the construction of sustainable development indices for the river basins of Rondônia. The management of watersheds is still very ineffective, despite being regulated by state law. It is highly recommended to institutionalize regional public policies in the form of a Master Plan for the Rondônia Watershed.
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Dutta, D., S. Kim, J. Vaze, and J. Hughes. "Streamflow predictions in regulated river systems: hydrological non-stationarity versus anthropogenic water use." Proceedings of the International Association of Hydrological Sciences 371 (June 12, 2015): 35–42. http://dx.doi.org/10.5194/piahs-371-35-2015.

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Abstract. Streamflow in a regulated river system is highly influenced by storage regulations and anthropogenic water use in addition to climate variability. Thus, changes in climate-streamflow relationships and dominant hydrological processes over time are difficult to quantify in a regulated system without partitioning influence of storage regulation and anthropogenic water uses. This requires a robust regulated river system model, which takes into consideration of both hydrological and man-made flow regulation processes, as well as anthropogenic water uses. In this study, a newly developed large-scale river system model (called "AWRA-R") was used to assess the influence of both anthropogenic and climate variability/change on streamflow non-stationarity in the Murray Darling Basin (MDB). MDB is one of the highly regulated basins in Australia with multiple large and small storages developed primarily for supplying water to irrigated agriculture. The modelling was undertaken for the period of 1950–2010, which includes rapid water resources development and both wet and dry climate. The AWRA-R model was calibrated for a reasonably long period and then, validated on an independent period. The calibrated parameters were used to simulate streamflow under current and pre-development conditions to analyse the streamflow variability and influence of climate variability and anthropogenic development on streamflow trend. This paper briefly introduces the model and the method used for assessing streamflow variability under natural and developed conditions and presents the results and findings.
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Zhang, Y. Y., Q. X. Shao, A. Z. Ye, and H. T. Xing. "An integrated water system model considering hydrological and biogeochemical processes at basin scale: model construction and application." Hydrology and Earth System Sciences Discussions 11, no. 8 (August 4, 2014): 9219–79. http://dx.doi.org/10.5194/hessd-11-9219-2014.

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Abstract. Integrated water system modeling is a reasonable approach to provide scientific understanding and possible solutions to tackle the severe water crisis faced over the world and to promote the implementation of integrated river basin management. Such a modeling practice becomes more feasible nowadays due to better computing facilities and available data sources. In this study, the process-oriented water system model (HEXM) is developed by integrating multiple water related processes including hydrology, biogeochemistry, environment and ecology, as well as the interference of human activities. The model was tested in the Shaying River Catchment, the largest, highly regulated and heavily polluted tributary of Huai River Basin in China. The results show that: HEXM is well integrated with good performance on the key water related components in the complex catchments. The simulated daily runoff series at all the regulated and less-regulated stations matches observations, especially for the high and low flow events. The average values of correlation coefficient and coefficient of efficiency are 0.81 and 0.63, respectively. The dynamics of observed daily ammonia-nitrogen (NH4N) concentration, as an important index to assess water environmental quality in China, are well captured with average correlation coefficient of 0.66. Furthermore, the spatial patterns of nonpoint source pollutant load and grain yield are also simulated properly, and the outputs have good agreements with the statistics at city scale. Our model shows clear superior performance in both calibration and validation in comparison with the widely used SWAT model. This model is expected to give a strong reference for water system modeling in complex basins, and provide the scientific foundation for the implementation of integrated river basin management all over the world as well as the technical guide for the reasonable regulation of dams and sluices and environmental improvement in river basins.
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Jiang, Dejuan, and Kun Wang. "The Role of Satellite-Based Remote Sensing in Improving Simulated Streamflow: A Review." Water 11, no. 8 (August 4, 2019): 1615. http://dx.doi.org/10.3390/w11081615.

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A hydrological model is a useful tool to study the effects of human activities and climate change on hydrology. Accordingly, the performance of hydrological modeling is vitally significant for hydrologic predictions. In watersheds with intense human activities, there are difficulties and uncertainties in model calibration and simulation. Alternative approaches, such as machine learning techniques and coupled models, can be used for streamflow predictions. However, these models also suffer from their respective limitations, especially when data are unavailable. Satellite-based remote sensing may provide a valuable contribution for hydrological predictions due to its wide coverage and increasing tempo-spatial resolutions. In this review, we provide an overview of the role of satellite-based remote sensing in streamflow simulation. First, difficulties in hydrological modeling over highly regulated basins are further discussed. Next, the performance of satellite-based remote sensing (e.g., remotely sensed data for precipitation, evapotranspiration, soil moisture, snow properties, terrestrial water storage change, land surface temperature, river width, etc.) in improving simulated streamflow is summarized. Then, the application of data assimilation for merging satellite-based remote sensing with a hydrological model is explored. Finally, a framework, using remotely sensed observations to improve streamflow predictions in highly regulated basins, is proposed for future studies. This review can be helpful to understand the effect of applying satellite-based remote sensing on hydrological modeling.
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Amat-Trigo, Fátima, Mar Torralva, Daniel González-Silvera, Francisco Javier Martínez-López, and Francisco José Oliva-Paterna. "Plasticity in Reproductive Traits, Condition and Energy Allocation of the Non-Native Pyrenean Gudgeon Gobio lozanoi in a Highly Regulated Mediterranean River Basin." Water 13, no. 3 (February 2, 2021): 387. http://dx.doi.org/10.3390/w13030387.

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The invasion success of non-native fish, such as Pyrenean gudgeon Gobio lozanoi in several Iberian rivers, is often explained by the expression of its life history traits. This study provides the first insights into the reproductive traits, fish condition, and energy allocation (protein and lipid contents of tissues) of this species, along a longitudinal gradient in one of the most regulated river basins in the Iberian Peninsula, the Segura river. Larger sizes of first maturity, higher fecundity and larger oocytes were found in fluvial sectors with the most natural flow regimes, characterised by a low base flow with high flow peaks in spring and autumn. A delay in the reproductive period, lower fish condition and no differences in sex-ratio were observed in fluvial sectors with a high increase in base flow and notable inversion in the seasonal pattern of flow regime. Lipid contents in the liver and gonads were stable during the reproductive cycle and decreases in muscle were noted, whereas ovarian and liver proteins increased. In relation to energy allocation for G. lozanoi, an intermediate energy strategy was observed between income and capital breeding. Our results support the hypothesis that the high plasticity of G. lozanoi population traits plays a significant role in its success in a highly regulated Mediterranean river basin. Understanding the mechanisms by which flow regulation shapes fish populations in Mediterranean type-rivers could inform management actions.
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Dibike, Yonas B., Rajesh R. Shrestha, Colin Johnson, Barrie Bonsal, and Paulin Coulibaly. "Assessing Climatic Drivers of Spring Mean and Annual Maximum Flows in Western Canadian River Basins." Water 13, no. 12 (June 8, 2021): 1617. http://dx.doi.org/10.3390/w13121617.

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Flows originating from cold and mountainous watersheds are highly dependent on temperature and precipitation patterns, and the resulting snow accumulation and melt conditions, affecting the magnitude and timing of annual peak flows. This study applied a multiple linear regression (MLR) modelling framework to investigate spatial variations and relative importance of hydroclimatic drivers of annual maximum flows (AMF) and mean spring flows (MAMJflow) in 25 river basins across western Canada. The results show that basin average maximum snow water equivalent (SWEmax), April 1st SWE and spring precipitation (MAMJprc) are the most important predictors of both AMF and MAMJflow, with the proportion of explained variance averaging 51.7%, 44.0% and 33.5%, respectively. The MLR models’ abilities to project future changes in AMF and MAMJflow in response to changes to the hydroclimatic controls are also examined using the Canadian Regional Climate Model (CanRCM4) output for RCP 4.5 and RCP8.5 scenarios. The results show considerable spatial variations depending on individual watershed characteristics with projected changes in AMF ranging from −69% to +126% and those of MAMJflow ranging from −48% to +81% by the end of this century. In general, the study demonstrates that the MLR framework is a useful approach for assessing the spatial variation in hydroclimatic controls of annual maximum and mean spring flows in the western Canadian river basins. However, there is a need to exercise caution in applying MLR models for projecting changes in future flows, especially for regulated basins.
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Zhang, Y. Y., Q. X. Shao, A. Z. Ye, H. T. Xing, and J. Xia. "Integrated water system simulation by considering hydrological and biogeochemical processes: model development, parameter sensitivity and autocalibration." Hydrology and Earth System Sciences Discussions 12, no. 5 (May 22, 2015): 4997–5053. http://dx.doi.org/10.5194/hessd-12-4997-2015.

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Abstract. Integrated water system modeling is a reasonable approach to provide scientific understanding of severe water crisis faced all over the world and to promote the implementation of integrated river basin management. Time Variant Gain Model (TVGM), which is a classic hydrological model, is based on the complex Volterra nonlinear formulation and has gotten good performance of runoff simulation in numerous basins. However, TVGM is disadvantageous to predict other water-related components. In this study, TVGM was extended to an integrated water system model by coupling multiple water-related processes in hydrology, biogeochemistry, water quality and ecology, and considering the interference of human activities. The parameter sensitivity and autocalibration modules were also developed to improve the simulation efficiency. The Shaying River Catchment, which is the largest, highly regulated and heavily polluted tributary in the Huai River Basin of China, was selected as the study area. The key water related components (e.g., runoff, water quality, nonpoint source pollutant load and crop yield) were simulated. The results showed that the extended model produced good simulation performance of most components. The simulated daily runoff series at most regulated and less-regulated stations matched well with the observations. The average values of correlation coefficient and coefficient of efficiency between the simulated and observed runoffs were 0.85 and 0.70, respectively. The simulations of both low and high flow events were improved when the dam regulation was considered except the low flow simulation at Zhoukou and Huaidian stations. The daily ammonia-nitrogen (NH4-N) concentration, as a key index to assess water quality in China, was well captured with the average correlation coefficient of 0.67. Furthermore, the nonpoint source NH4-N load and corn yield were simulated for each administrative region and the results were reasonable in comparison with the data from the official report and the statistical yearbooks, respectively. This study is expected to provide a scientific support for the implementation of such a modeling practice for integrated river basin management.
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Zhang, Shuai, and Huilin Gao. "Using the Digital Elevation Model (DEM) to Improve the Spatial Coverage of the MODIS Based Reservoir Monitoring Network in South Asia." Remote Sensing 12, no. 5 (February 25, 2020): 745. http://dx.doi.org/10.3390/rs12050745.

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Satellite remote sensing of near real-time reservoir storage variations has important implications for flood monitoring and water resources management. However, satellite altimetry data, which are essential for estimating storage variations, are only available for a limited number of reservoirs. This lack of high-density spatial coverage directly hinders the potential use of remotely sensed reservoir information for improving the skills of hydrological modeling over highly regulated river basins. To solve this problem, a reservoir storage dataset with high-density spatial coverage was developed by combining the water surface area estimated from Moderate Resolution Imaging Spectroradiometer (MODIS) imageries with the Digital Elevation Model (DEM) data collected by the Shuttle Radar Topography Mission (SRTM). By including more reservoirs, this reservoir dataset represents 46.6% of the overall storage capacity in South Asia. The results were validated over five reservoirs where gauge observations are accessible. The storage estimates agree well with observations, with coefficients of determination ranging from 0.47 to 0.91 and normalized root mean square errors (NRMSE) ranging from 15.46% to 37.69%. Given the general availability of MODIS and SRTM data, this algorithm can be potentially applied for monitoring global reservoirs at a high density.
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Дисертації з теми "Highly regulated basins"

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Hinegk, Luigi. "Long-term evolution of highly regulated basins and water management policies to support their ecosystem services." Doctoral thesis, Università degli studi di Trento, 2022. http://hdl.handle.net/11572/354821.

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Water management is facing a growing number of challenges in many river basins worldwide, as the equal distribution of the available water resources is increasingly influenced by several, uncertain climatic and anthropic pressures. Within the current and projected water scarcity and drought scenario, such issue represents even a greater challenge in those basins that have been massively regulated in the XX century, as water managers are asked to find balanced policies to stay ahead with multiple, interdependent and ever-increasing water-related requirements. In this context, water conflict has become a recurring problem, with the freshwater ecosystems becoming the sole providers of unbearable human water needs and experiencing a severe alteration of their natural renewability and ecological integrity. In fact, the concern of sustaining the freshwater ecosystems has evolved throughout the years, coming to the fore since the 1990s under the concept of "ecosystem services", defined as the multiple benefits that people obtain from ecosystems. With a high number of challenges still ahead for implementing such paradigm in real-world water management practices, few investigations inspect the long-term evolution of highly regulated basins, being vulnerable freshwater systems characterized by a profusion of ecosystem services in a context of complex management policies and changing anthropic and climatic pressures. We focus our attention on the highly interconnected Garda-Mincio system (Northern Italy), further broadening the results to the regulated basins of the European perialpine region. First, to examine the modification of the freshwater systems from their pristine to their regulated conditions, we carried out an extensive collection of daily hydro-meteorological data by consulting public online sources as well as digitizing historical data contained in hand-written documents. The resulting database, which represents a valuable source of long-term daily hydro-meteorological data for the Garda-Mincio system, additionally underscored the complexity of constructing and maintaining a consistent and up-to-date database within an inter-regional context. The collected data were then adopted to investigate the climatic and anthropogenic drivers that have progressively influenced water availability, the provision of the changing water demands and the trade-offs with the existing water ecosystem services over the last two centuries. Statistical analyses were performed to outline the evolution of the annual and seasonal trends of Lake Garda water levels and outflows over the period 1888-2020, discussing the role of the Salionze Dam operational rules (completed in 1951) as well as the influence of the main water needs of the downstream Mincio River basin (i.e. hydropower production, irrigation and fluvial ecosystem sustenance). The role of hydro-meteorological factors was assessed by implementing a water balance model for Lake Garda, the largest lake in Italy, over the period 1928-2020, performing uncertainty and sensitivity analyses on specific water balance components (i.e. over-lake evaporation and basin evapotranspiration). We then focus our analyses on the management of the hydraulic infrastructures that regulate the first and highly water-stressed stretch of the Mincio River downstream Lake Garda, i.e. the Salionze Dam and the Pozzolo-Marenghello infrastructures, where both high and low flow conditions reveal the inability of the current operational rules to support the new variety of water abstractions while maintaining appropriate environmental flow conditions and flood protection. These analyses were carried out through in-situ measurements and numerical simulations, updating the aging rating curves of the existing hydraulic infrastructures. Drawing on the Garda-Mincio system, we inspected the evolution of the freshwater regimes within the European perialpine lakes framework, discussing the outcomes to describe which common factors drove management policies in the area. Eventually, we discuss our outcomes recommending future sustainable and adaptive water management policies in the area.
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Werkstetter, Mario. "Hocheffizienter DC/DC-Wandler auf Basis von GaN-Leistungsschaltern für Hochleistungs-Leuchtdioden im Kraftfahrzeug." Universitätsverlag der Technischen Universität Chemnitz, 2017. https://monarch.qucosa.de/id/qucosa%3A20870.

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In der vorliegenden Arbeit werden Möglichkeiten zur Maximierung der Effizienz von stromregelnden DC/DC-Wandlern für den Betrieb von Hochleistungs-LEDs in PKW-und Motorrad-Beleuchtungseinrichtungen untersucht, mit dem Ziel, das Gewicht und den Energieverbrauch der Steuergeräte zu reduzieren und so zu dem stetigen Bestreben der Minimierung der Gesamtfahrzeugemissionen beizutragen. Dafür werden verschiedene, teils sequenziell aufbauende Maßnahmen in Topologie, Bauelementen, Dimensionierung und Betriebsart betrachtet. Eine grundlegende Herausforderung für die Auslegung der Schaltung stellt dabei deren universelle Verwendbarkeit als Gleichteil in einem großen Bereich an Ausgangsstrom und -spannung in den individuellen Scheinwerfersystemen der verschiedenen Fahrzeugderivate dar. Die Grundlage für die Verringerung der Verlustleistung bildet die Vereinfachung der Schaltreglertopologie hinsichtlich des Bauteilaufwands. Dies wird durch die Versorgung der Schaltung aus dem 48 V-Energiebordnetz und die Verwendung der Topologie des Tiefsetzstellers erreicht. Elementarer Anteil dieser Arbeit ist die Untersuchung der Wirksamkeit des Einsatzes neuartiger Galliumnitrid-Leistungsschalter (GaN-HEMTs) anstelle der konventionellen Silizium-MOSFETs, was zunächst an Hand von Berechnungen und schaltungstechnischen, parasitärbehafteten und zeitvarianten Simulationen durchgeführt wird. Bereits bei herkömmlichen Schaltfrequenzen und hartgeschaltetem Betrieb können signifikante Verbesserungen des Wirkungsgrades erreicht werden. Weitergehend wird der Nutzen der durch die GaN-Transistoren ermöglichten höheren Schaltfrequenzen eruiert. Die um bis zu Faktor 20 erhöhte Schaltfrequenz macht den Einsatz einer resonanten Betriebsart (Zero-Voltage-Switching) und einer Luftspule als Hauptinduktivität notwendig. Auf Steuergeräteebene kann somit die Verlustleistung auf unter ein Drittel reduziert werden, was zudem ein deutlich einfacheres und kompakteres Gehäuse ermöglicht, wodurch das Gesamtgewicht etwa halbiert werden kann. Abschließend wird die Schaltung in einem Prototypen praktisch umgesetzt und die Funktionsfähigkeit im ZVS-Betrieb bei Schaltfrequenzen von bis zu 10 MHz verifiziert.
This thesis deals with the research of possibilities for maximising efficiency of current-regulating DC/DC-Converters for driving high-power-LEDs in passenger-car- and motorcycle-lighting-devices. The ambition is to reduce weight and energy-consumption of the electronic-control-units, to contribute to reach the continuously decreasing target-values for vehicle-emissions. Therefor different approaches in topology, components, design and operating mode are considered. A key-challenge for the circuit-design is the common-part-strategy for usage in many individual vehicle-headlamp-systems with a wide range of output-current and LED-string-voltages. Basis for the reduction of power-losses is the simplification of the converters topology in terms of quantity of components. This is achieved by using the 48 V -vehicle-electrical-system as voltage-supply and a step-down-topology. Mainpart of this research is about the potential benefits of applying novel Galliumnitride High-electron-mobility-transistors (GaN-HEMTs) instead of silicon MOS-FETs. Initially this is done by calculations and parasitic-afflicted, timevariant circuit-simulations. Already in hardswitching operation under conventional switching-frequencies significant improvements in converter-efficiency can be achieved. Furthermore the advantages of higher switching-frequencies, offered by the GaN-transistors, are investigated. Up to 20 times higher switching-frequencies necessitate a resonant operating mode of the circuit (Zero-voltage-switching) and the use of an aircoil as main-inductor. On ECU-level power-losses can be reduced down to less than one third, which enables a more simplified and compact housing-concept, so that the overall weight can drop to about the half. Finally the designed circuit is build up in a prototype and the functional capability is verified in ZVS-mode with up to 10 MHz switching-frequency.
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Книги з теми "Highly regulated basins"

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Yadgarov, Yakov. History of economic thought. ru: INFRA-M Academic Publishing LLC., 2020. http://dx.doi.org/10.12737/1059100.

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The textbook presents the course of history of economic doctrines in accordance with the General plan of previous editions. Discusses the economic doctrine of the era of pre-market economy (including the economic thought of the Ancient world and middle Ages), mercantilism, classical political economy, socio-economic reform projects of economic romanticism, utopian socialism, German historical school, marginalism. To the era of regulated market relations are covered in the textbook socio-institutional direction, the theory of market with imperfect competition, Keynesian Economics, neoliberalism, the concept of the neoclassical synthesis, neo-institutionalism, the phenomenon of the Russian school of economic thought. Special attention is given to synthesis as the basis of modern theories of value. Meets the requirements of Federal state educational standards of higher education of the last generation. For students enrolled in the specialty 38.03.01 "Economics", graduate students, researchers and anyone interested in the history of world and domestic economic thought.
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Korolev, Vitaliy, Dmitriy Berdnikov, Aleksandr Geller, Oksana Kirillova, Sergey Vasin, Roman Kirillov, Ivan Kapitonov, et al. Antimonopoly and tariff regulation in the system of state control of the Russian Federation. ru: INFRA-M Academic Publishing LLC., 2023. http://dx.doi.org/10.12737/1862723.

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The textbook extensively covers the most pressing issues of antimonopoly and tariff regulation. The basics of antimonopoly and tariff regulation are outlined, the main activities of the Federal Antimonopoly Service as a state regulator, its functions, powers and responsibilities in the implementation of state antimonopoly control and tariff policy, as well as issues of sectoral tariff regulation and control over economic concentration are considered. Separate chapters are devoted to: types of unfair advertising and measures of responsibility for its placement; control of procurement activities. Various approaches to assessing the prospects for the development of corporations in a competitive environment are presented, for example, PPP, which, on the one hand, acts as a development tool, and on the other — as an object of antimonopoly regulation. The essence of the antimonopoly compliance method, which is used to prevent regulatory risks, is disclosed. Meets the requirements of the federal state educational standards of higher education of the latest generation. For students studying in the areas of training "Management" and "Jurisprudence" (bachelor's and master's levels), studying issues of competition, antimonopoly control and tariff policy from the point of view of management in these areas.
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Stern, Daniel N. A Possible Neuroscientific Basis for Vitality Forms. Oxford University Press, 2015. http://dx.doi.org/10.1093/med:psych/9780199586066.003.0004.

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Анотація:
Chapter 4 discusses possible neuroscientific bases for vitality forms and the arousal systems. The chapter outlines how the arousal systems provide the felt ‘force’ of vitality dynamics, if the arousal systems are regulated from higher centers, and the specificity of the arousal systems.
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Beattie, R. Mark, Anil Dhawan, and John W.L. Puntis. Cystic fibrosis. Oxford University Press, 2011. http://dx.doi.org/10.1093/med/9780198569862.003.0021.

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Gastrointestinal manifestations 156Management of gastrointestinal symptoms in children with CF 158Nutrition in CF 158Nutritional management 159Vitamins 160The incidence of cystic fibrosis (CF) is around 1 in 2500. Cases are diagnosed as a consequence of population screening or high-risk screening, or following presentation with clinical symptoms typical of the disorder. The basic defect is in the CFTR (cystic fibrosis transmembrane conductance regulator) protein which codes for a cyclic adenosine monophosphate-regulated chloride transporter in epithelial cells of exocrine organs. This is involved in salt and water balance across epithelial surfaces. The gene is on chromosome 7. There are multiple known mutations, the most common being ...
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5

Iversen, Les. 2. How drugs work. Oxford University Press, 2016. http://dx.doi.org/10.1093/actrade/9780198745792.003.0002.

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‘How drugs work’ outlines the basic mechanisms of pharmacology. Drugs are chemicals that can be naturally occurring or man-made, and which can be administered in a variety of ways. They can act on receptors—often highly specific proteins in cells which can up-regulate or down-regulate processes—or on other targets, such as DNA or enzymes. The molecular action of drugs can be investigated in a lab, but the effects on the whole organism are more important. Effective doses need to be determined, taking into account metabolic rates, drug interactions, and side effects. Prolonged drug use can cause tolerance and substance addiction.
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Zhou, Clarence. LIN System Basis Chip Including LIN Transceiver, Voltage Regulator, Dual Low Side Driver and a High Side Switch. Microchip Technology Incorporated, 2018.

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7

Wolters-Broder, Lisa. ATA663331/54 LIN System Basis Chip Including LIN Transceiver, Voltage Regulator, Dual Low Side Driver and a High Side Switch. Microchip Technology Incorporated, 2017.

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8

Clarke, Andrew. Torpor and hibernation. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780199551668.003.0011.

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A diurnal (circadian) rhythm in body temperature is a widespread, and possibly universal, feature of endotherms. Some mammals and birds down-regulate their metabolic rate significantly by night, allowing their body temperature to drop sufficiently that they become inactive and enter torpor. Both the minimum temperature achieved and the duration of torpor are highly variable. Daily torpor is principally a response to reduced energy intake, and a drop in ambient temperature. Hibernation is essentially an extreme form of torpor. Small mammals hibernating at high latitudes have regular arousals during which they urinate and may feed. Bears hibernate with relatively high body temperature, and do not undergo arousal. Only one bird, the poorwill, is known to hibernate. Rewarming during arousal may be fuelled exclusively by metabolism (for example in small mammals in the Arctic) or with significant energy input from basking (for example in subtropical arid areas). The capacity for torpor appears to be an ancestral character in both mammals and birds, possibly related to the origin of endothermy in small species subject to marked diurnal and/or seasonal variation in body temperature. Both deep hibernation and strict endothermy are probably derived characteristics.
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9

Campione, Marina, Amelia Aranega, and Diego Franco. Cardiac looping and laterality. Edited by José Maria Pérez-Pomares, Robert G. Kelly, Maurice van den Hoff, José Luis de la Pompa, David Sedmera, Cristina Basso, and Deborah Henderson. Oxford University Press, 2018. http://dx.doi.org/10.1093/med/9780198757269.003.0014.

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Dextral looping is a complex process which progresses concomitantly with cardiac chamber differentiation and ultimately leads to the final alignment of the cardiac regions. Generation of cardiac asymmetry is crucial to ensure the proper form and consequent function of the heart and thus is a highly regulated process. Molecular signals originate long before morphological asymmetry and therefore can direct it; a complex regulatory network has been characterized which invariably converges on the Tgf-β‎ signalling molecule Nodal and its downstream target, the homeobox transcription factor Pitx2. We review current data regarding the cellular and molecular bases of cardiac looping and laterality, and describe current understaning of the role of Nodal and Pitx2. The morphogenetic role of the Pitx2 gene and its modulation of transcription and function, which have recently linked laterality to atrial fibrillation, are emphasized.
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Simon, Gleeson. Part II Commercial Banking, 9 Model-Based Approaches to Risk Weighting. Oxford University Press, 2018. http://dx.doi.org/10.1093/law/9780198793410.003.0009.

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This chapter discusses the Basel risk model. Every financial institution expects to suffer some level of default. Consequently, all properly run banks make provisions for some level of default on their existing assets. This is known as expected loss. At some points losses will be lower than those expected, and at some points they will be higher. The task of the regulator is to set a capital requirement which just skims the top of the actual loss experience curve. If the capital requirement is set significantly higher than this, then banks will be penalized by being required to hold excessive capital, if it is set lower, then the risk of bank failure increases. The remainder of the chapter covers Value at Risk and the Basel framework; the basic Basel formula; specific amendments for different classes; translating between capital requirements and risk weightings; illustrative risk weights; and variations in credit risk weightings between firms.
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Частини книг з теми "Highly regulated basins"

1

Upadhyay, Upashna, Poonam Kaithal, Preetam Verma, Rohit Lall, and Poonam Singh. "Analysis of Pectin in Different Citrus Fruits and Evolutionary Relationship." In Proceedings of the Conference BioSangam 2022: Emerging Trends in Biotechnology (BIOSANGAM 2022), 268–75. Dordrecht: Atlantis Press International BV, 2022. http://dx.doi.org/10.2991/978-94-6463-020-6_26.

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AbstractPectin is a polysaccharide present in fruit cell walls can be extracted from fruit wastes obtained after processing. The objective of the present investigation was to study the potential of citrus fruit peels to be a source of pectin as it is of great importance in food and medical industry. This study aimed at comparing the characteristics of different pectin and to see which one is more suitable for industrial application. Pectin was extracted using alcohol precipitation method from peels of grapefruit, mousambi, and orange so that the use of pectin can be applied to a wider range. According to the study, the pectin extracted by mousambi on wet basis (17.1%) was higher in comparison to the pectin extraction of orange and grapefruit. The pectin can be used in many fields like food and medicines so the improvement in quality and production is very important. MicroRNAs have the main function of guiding the base pairing with target mRNA to negatively regulate its expression for gene silencing via mRNA clevage. In the present study we also found the phylogenetic relationship among the citrus fruits by multiple sequence alignment of microRNAs stem-loop sequence from the miRbase database of the citrus fruits and after getting phylogenetic tree we got the common ancestors. In recent years, the center of production has moved to Europe and to citrus- producing countries like Mexico and Brazil. Further changes of structure and location of the industry continue, but are constrained by the need for large capital investment to setup Plant of economic size, and the need for a large-scale source or sources of raw material.
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2

Mahat, Marian, and Alan Pettigrew. "The Regulatory Environment of Non-Profit Higher Education and Research Institutions and Its Implications for Managerial Strategy." In Handbook of Research on Emerging Business Models and Managerial Strategies in the Nonprofit Sector, 336–51. IGI Global, 2017. http://dx.doi.org/10.4018/978-1-5225-2537-0.ch017.

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The concept of strategy in non-profit higher education is a contested issue. It is argued that strategy, in the business sense, does not apply to a substantially public and more institutionalized sector such as higher education and is not achievable in complex, loosely coupled organizations such as universities. Additionally, strategy does not sit easily with organizations operating in regulated contexts limiting competitive market pressures. This chapter discusses the regulatory environment of non-profit higher education by focusing on one of the most highly regulated disciplines: medical education and research. The chapter will begin by developing a context for discussion by firstly mapping the landscape of Australian medical education and research. Subsequently, the chapter argues that medical schools and research institutes need to exercise as much discretion as they can in the area under their control, develop sound strategies to deal with their changed circumstances, and develop a coherent and defensible basis for decision making through assessing their environment.
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Zambrano-Matamala, Carolina, Darío Rojas-Diaz, Pedro Salcedo-Lagos, Felipe Albarran-Torres, and Alejandro Diaz-Mujica. "Perception of Student-Teachers Regarding Self-Regulated Learning." In Pedagogy in Basic and Higher Education - Current Developments and Challenges. IntechOpen, 2020. http://dx.doi.org/10.5772/intechopen.88728.

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4

Muza, Rexford. "General approach to sleep disorders." In Oxford Handbook of Sleep Medicine, 9–20. Oxford University Press, 2022. http://dx.doi.org/10.1093/med/9780192848253.003.0002.

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Sleep represents a behavioural state of mental and physical arrest, associated with disconnection from the outside world. Yet underlying this apparent state of quiescence exist a highly active and dynamic series of brain states, tightly regulated and with a range of specific functions. In this chapter, sleep and its stages are described, as are the neuroanatomical and neurotransmitter basis of sleep. The importance of sleep in the regulation of brain function, in the form of memory, learning and the glymphatic system are also described.
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5

Chatterjee, Shamik, Vikram Kumar Kamboj, and Bhavana Jangid. "PID Plus Second Order Derivative Controller for Automatic Voltage Regulator Using Linear Quadratic Regulator." In AI Techniques for Reliability Prediction for Electronic Components, 262–87. IGI Global, 2020. http://dx.doi.org/10.4018/978-1-7998-1464-1.ch015.

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This chapter presents linear quadratic regulator (LQR) for tuning the parameters of four-term proportional-integral-derivative plus second order derivative controller for controlling terminal voltage of alternator equipped with automatic voltage regulator (AVR) system. Different optimization techniques are considered for juxtaposition with the proposed controller on the basis of terminal voltage response profiles of the AVR system, and Bode plot analysis is carried out for comparing the frequency responses, and through root locus, the stability of the proposed controller is investigated. On-line responses are obtained by implementing a fast performing Sugeno fuzzy logic technique in the controller for working in off-nominal and on-line situations. The controller has undergone an investigation, while having changed system parameters, for the analysis of the robustness of the proposed controller. It is revealed that the performance of the proposed LQR-based controller exhibits a highly improved robust control system for controlling the AVR in power systems.
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"Balancing Fisheries Management and Water Uses for Impounded River Systems." In Balancing Fisheries Management and Water Uses for Impounded River Systems, edited by Christopher J. Goudreau, Richard W. Christie, and D. Hugh Barwick. American Fisheries Society, 2008. http://dx.doi.org/10.47886/9781934874066.ch5.

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<em>Abstract</em>.—The Catawba-Wateree river basin is a highly regulated system in North Carolina and South Carolina that includes 11 main-stem reservoirs and four regulated riverine reaches. The reservoirs support typical southeastern U.S. warmwater fisheries, while the riverine reaches support a variety of species, including trout and several diadromous fishs. The reservoirs and regulated river reaches provide multiple uses, including hydroelectric generation, drinking water, cooling water for electric power plants, recreation, and residential development. As part of the relicensing process for the hydroelectric developments, many stakeholders were convened to study and negotiate a comprehensive relicensing agreement. A computer model was used to assess the combined effects of various operating regimes, water-use amounts, and hydrologic conditions on reservoir levels, river flows, and hydroelectric generation. The model used projections of the effects of increased population growth, water use, and reservoir sedimentation for a period 50 years into the future. Model outputs were postprocessed to further understand the impacts to aquatic habitat, recreation, aesthetics, hydropower generation, and water supply. Although future demand for water resources exceeded the available supply under some conditions, an acceptable balance was reached after extensive negotiation. The objectives of this paper are to describe how the relicensing process was used to arrive at a balanced management plan for water and other resources in a large basin, describe some of the tools used to assist the decision-making process, and to list some important lessons that can assist others in designing a framework for other water allocation efforts.
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Hinegk, L., L. Adami, G. Zolezzi, and M. Tubino. "Optimization of water resources in highly regulated rivers: A case study from the Garda-Mincio basin, Italy." In River Flow 2020, 2196–202. CRC Press, 2020. http://dx.doi.org/10.1201/b22619-307.

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Kaushik, Shivam, Shivangi Rawat, and Pinky Kain. "Drosophila Central Taste Circuits in Health and Obesity." In Obesity and Health [Working Title]. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.99643.

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When there is a perturbation in the balance between hunger and satiety, food intake gets mis-regulated leading to excessive or insufficient eating. In humans, abnormal nutrient consumption causes metabolic conditions like obesity, diabetes, and eating disorders affecting overall health. Despite this burden on society, we currently lack enough knowledge about the neuronal circuits that regulate appetite and taste perception. How specific taste neuronal circuits influence feeding behaviours is still an under explored area in neurobiology. The taste information present at the periphery must be processed by the central circuits for the final behavioural output. Identification and understanding of central neural circuitry regulating taste behaviour and its modulation by physiological changes with regard to internal state is required to understand the neural basis of taste preference. Simple invertebrate model organisms like Drosophila melanogaster can sense the same taste stimuli as mammals. Availability of powerful molecular and genetic tool kit and well characterized peripheral gustatory system with a vast array of behavioural, calcium imaging, molecular and electrophysiological approaches make Drosophila an attractive system to investigate and understand taste wiring and processing in the brain. By exploiting the gustatory system of the flies, this chapter will shed light on the current understanding of central neural taste structures that influence feeding choices. The compiled information would help us better understand how central taste neurons convey taste information to higher brain centers and guide feeding behaviours like acceptance or rejection of food to better combat disease state caused by abnormal consumption of food.
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Kalchenko, Larysa. "THE CONCEPTUAL IDEAS OF THE CONSTRUCTIVISM THEORY AS A BASIS FOR THE MODERNIZATION OF THE EDUCATIONAL SPACE AND THE ORGANIZATION OF THE PERSONAL LEARNING ENVIRONMENT OF STUDENTS OF HIGHER EDUCATION INSTITUTIONS." In EDUCATIONAL SPACE: POST-NON-CLASSICAL PERSPECTIVES, 35–47. Varna University of Management, 2023. http://dx.doi.org/10.54055/fqwa4301.

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The article presents the main ideas of the theory of constructivism as a component of the modern philosophy of education and substantiates the role, purpose, functions, and values of the lecturer of a higher educational institution in the context of the modernization of the educational space of higher educational institution. The main components of the process of organizing a personal learning environment for students of higher education institution in the conditions of the challenges of the information society are defined and disclosed, as conditions for theirs successful integration into the modern system of higher education, disclosure and realization of individual inclinations and students’ abilities in the educational process by making a personal educational network. Outlined a three-level pedagogical structure that professors and lectures can use to enhance self-regulated learning by means of PLEs.
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10

Coll, Anthony P. "The Physiology of Bodyweight Regulation." In Oxford Textbook of Endocrinology and Diabetes 3e, edited by John A. H. Wass, Wiebke Arlt, and Robert K. Semple, 1807–14. Oxford University Press, 2021. http://dx.doi.org/10.1093/med/9780198870197.003.0222.

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Mammalian body weight is highly regulated. An understanding of the processes governing body weight is closely relevant to clinical practice as disorders of energy homeostasis are common, cause significant morbidity and mortality and can be challenging to treat. Detailed clinical observation of extreme phenotypes, both human and model organism, coupled with significant advances in molecular biology have led to the identification of a host of endocrine pathways that control appetitive behaviour, body composition, and energy expenditure. Compelling data show the central nervous system, in particular regions such as the hypothalamus and brainstem, have primacy in sensing a multitude of humoral and neuronal signals from the periphery, integrating them into a coordinated output that aims to maintain weight in the face of a changing environment. This understanding not only gives a biological basis for interindividual variation in body weight, but has opened up new avenues for rational therapeutic interventions.
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Тези доповідей конференцій з теми "Highly regulated basins"

1

Antipin, A. S., V. N. Udintsev, and S. L. Nazarov. "Exciter synchronous machine low power on the basis of high-speed regulator current." In 2017 International Conference on Industrial Engineering, Applications and Manufacturing (ICIEAM). IEEE, 2017. http://dx.doi.org/10.1109/icieam.2017.8076337.

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2

Stukalina, Yulia. "MAIN STANDARDS FOR INTERNAL AND EXTERNAL QUALITY ASSURANCE IN THE EUROPEAN HIGHER EDUCATION AREA." In Business and Management 2018. VGTU Technika, 2018. http://dx.doi.org/10.3846/bm.2018.01.

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The purpose of this paper is to provide a synthesis of the official documents that regulate quality as-surance activities in a modern univertsity. The principal objectives of the paper are to discuss the main standards for quality assurance in the European Higher Education Area, and examine the basic criteria applied for international institutional accreditation. The research method used in the paper in-cludes the review of official EU and OECD documents on quality assurance in higher education. The analysis conducted in the paper has allowed the author to identify and summarize key internal and external standards for quality assurance, which education managers should consider in the agenda of the all-inclusive management of an academia.
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3

Delgado, Anderson, Jorge Espinosa, Maria Hernandez, Gustavo Gonzalez, Luis Guanacas, William Aya, and Juan Perdomo. "New Mechanism of Sand Management Above ESPs: Cases Study in Colombia." In SPE Artificial Lift Conference and Exhibition - Americas. SPE, 2022. http://dx.doi.org/10.2118/209734-ms.

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Abstract One of the most expensive artificial lift systems in the oil industry is the Electric Submersible Pump (ESP) system, hence the unavoidable need of extending the run life of wells that have installed this system. Following the need of extending the run life, a sand regulator has been designed to protect the pump during shutdowns, and it has been incorporated into traditional sand control configurations to offer extensive protection above and below the pump. This paper will explain the mechanism of the sand regulator as well as the benefit of installing this system alone above the pump or complemented with a sand control system below the pump. The candidate wells to this integrated solution were selected from MMV (Middle Magdalena Valley) and Putumayo Basins, in Colombia. The wells had sand problems history and it was necessary to review pump designs, pulling reports and sensor parameters. Well conditions such as production, tubing size, and particle size distribution were analyzed to build the best design for every single well. In the design the geometry of the well was assessed to accommodate the cable and CT (Capillary tube) line downhole. The ADN Field in Colombia is characterized by heavy oil production (API between 13-18°), with fluid production between 1,000-2,000 BFPD, with a viscosity of 270 - 3090 cP @ 122°F, water cuts oscillating depending on the waterflooding effect (Between 1% to 95%) and high fine sand production (200 – 24,000 ppm). The CH Field wells produce between 1,000 – 6,000 BFPD, with API between 17-20°, high water cuts (&gt; 77%) and a high sand production between 100 – 3,000 ppm. The wells selected had other type of sand control and management systems and were highly affected by frequent shutdowns. The Sand Regulator design was installed in 20 wells and was compared with the performance achieved using traditional sand control solutions. After the installation, production has remained stable in all the wells applied, allowing to reduce the PIP of the well of up to 400 psi. Less current consumption has been observed after each shutdown in all the wells, extending the run life of some wells up to double the average. Sensor parameters were analyzed after each pump restart to determine how difficult it was to restart operation after shutdowns. Compared to the tools installed above the ESP, this sand regulator allows flushing operation through it with flow ranges from 0.5 to 5 bpm. In addition, the unconventional design of this tool has opened the door to a new concept of ESP protection that works in wells with light or heavy oil and can be refurbished or inspected completely without cutting the tool.
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4

Jiang, Long, Shikui Chen, and Peng Wei. "Concurrent Optimization of Structure Topology and Infill Properties With a Cardinal-Function-Based Parametric Level Set Method." In ASME 2018 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/detc2018-85408.

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In this paper, a parametric level-set-based topology optimization framework is proposed, to concurrently optimize structural topology at the macroscale as well as the infill material properties at the mesoscale. With the parametric level set framework, both the boundary evolution and the material property optimization during the optimization process are driven by the Method of Moving Asymptotes (MMA) optimizer, which is more efficient than the PDE-driven level set approach when handling nonlinear problems with multiple constraints. Rather than using a radial basis function (RBF) for the level set parameterization, a new type of cardinal basis function (CBF) was constructed as the kernel function for the proposed parametric level set approach. With this CBF kernel function, the bounds of the design variables can be defined explicitly, which is a great advantage compared with the RBF-based level set method. A variational approach was conducted to regulate the level set function to be a distance-regularized shape for a better material property interpolation accuracy and higher design robustness. With the embedded distance information from the level set model, boundary layer and the infill can be naturally discriminated.
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5

Bester, P., and T. Hill. "South African Licensing Framework for the Pebble Bed Modular Reactor." In Fourth International Topical Meeting on High Temperature Reactor Technology. ASMEDC, 2008. http://dx.doi.org/10.1115/htr2008-58185.

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The electrical utility in South Africa (Eskom) plan to construct a first of a kind Pebble Bed Modular Reactor (PBMR). It has been recognized that there is a need to adapt the licensing process for the PBMR to ensure that credible and effective licensing process be developed and implemented for this technology. This paper will briefly outline the regulatory framework within South Africa, explain the licensing process adopted and present the challenges that the South African National Nuclear Regulator (NNR) was facing in developing and implementing the licensing process and how these are being addressed. The paper will discuss the update of the regulatory framework and the gaps identified in terms of regulatory requirements needed for such a project. The scope of the regulatory assessment for the licensing of the PBMR is based on the licensing requirements and criteria defined by the NNR in regulatory documents that expand on the current legislative requirements. In addition guidance is provided on selected issues in regulatory guidance documents and position papers. The requirements comprise, besides the general requirements to respect good engineering practice and the ALARA and defense-in-depth principle, specific risk criteria and radiation dose limits. These are categorized for normal operation and operational occurrences as well as for design basis events and beyond design basis events for workers and the public. Additional requirements and recommendations are stipulated by the NNR on safety important areas like quality and safety management, qualification of the nuclear fuel and the core structures, core design, verification and validation of computer codes, source term analysis and others. Selected NNR Position Papers have been developed to elaborate and provide further clarification on NNR requirements. For preparation of the PBMR safety case so-called Key Licensing Issues have been defined and agreed with the applicant. Discussions relating to these Key Licensing Issues allow important nuclear safety aspects identified for the PBMR demonstration plant to be clarified in advance of the safety case submittal.
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Towfighian, S., G. R. Heppler, and E. M. Abdel-Rahman. "A Low Voltage Controller for a Chaotic Micro Resonator." In ASME 2010 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. ASMEDC, 2010. http://dx.doi.org/10.1115/detc2010-28990.

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The performance of a chaotic micro resonator is improved by redesigning a quadratic controller reported in a previous study. The chaotic micro resonator is composed of an electrostatic actuator and a voltage regulator (controller). The actuator is made of cantilever beam electrode above a fixed electrode. The actuator voltage, and consequently the electrostatic force magnitude, is controlled to drive the cantilever beam oscillations into chaos by creating a bi-stable regime in the system response. The performance of the redesigned controller is improved such that the system input voltage is reduced. The voltage generated by the controller is halved and the controller gains are smaller, which reduces the power and gain demands on the analogue controller components. The static and dynamic responses of the chaotic oscillator are studied and the sizes of the basins of attraction are compared for the improved and the original quadratic controllers. The controller can be configured to create two potential wells. The excitation DC voltages can then be adjusted to control the size of the upper and lower wells and thereby the basins of attraction around the two stable equilibria. As a result, one can shape the chaotic attractor to meet desired criteria. The reported chaos is intermittent chaos located in the lower well and between the two potential wells. This study can be used to design a new generation of nonlinear oscillators targeting high resolution sensors.
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Feng, Wenxing, Xiaoqiang Xiang, Guangming Jia, Lianshuang Dai, Yulei Gu, Xiaozheng Yang, Qingshang Feng, and Lijian Zhou. "Applying the Quantitative Risk Assessment (QRA) to Improve Safety Management of Oil and Gas Pipeline Stations in China." In 2012 9th International Pipeline Conference. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/ipc2012-90130.

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The oil and gas pipeline companies in China are facing unprecedented opportunities and challenges because of China’s increasing demand for oil and gas energy that is attributed to rapid economic and social development. Limitation of land resource and the fast urbanization lead to a determinate result that many pipelines have to go through or be adjacent to highly populated areas such as cities or towns. The increasing Chinese government regulation, and public concerns about industrial safety and environmental protection push the pipeline companies to enhance the safety, health and environmental protection management. In recent years, PetroChina Pipeline Company (PPC) pays a lot of attention and effort to improve employees and public safety around the pipeline facilities. A comprehensive, integrated HSE management system is continuously improved and effectively implemented in PPC. PPC conducts hazard identification, risk assessment, risk control and mitigation, risk monitoring. For the oil and gas stations in highly populated area or with numerous employees, PPC carries out quantitative risk assessment (QRA) to evaluate and manage the population risk. To make the assessment, “Guidelines for quantitative risk assessments” (purple book) published by Committee for the Prevention of Disasters of Netherlands is used along with a software package. The basic principles, process, and methods of QRA technology are introduced in this article. The process is to identify the station hazards, determinate the failure scenarios of the facilities, estimate the possibilities of leakage failures, calculate the consequences of failures and damages to population, demonstrate the individual risk and social risk, and evaluate whether the risk is acceptable. The process may involve the mathematical modeling of fluid and gas spill, dispersion, fire and explosion. One QRA case in an oil pipeline station is described in this article to illustrate the application process and discuss several key issues in the assessment. Using QRA technique, about 20 stations have been evaluated in PPC. On the basis of the results, managers have taken prevention and mitigation plans to control the risk. QRAs in the pipeline station can provide a quantitative basis and valuable reference for the company’s decision-making and land use planning. Also, QRA can play a role to make a better relationship between the pipeline companies and the local regulator and public. Finally, this article delivers limitations of QRA in Chinese pipeline stations and discusses issues of the solutions.
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Barinov, Evgeny, Nadezhda Dobrovolskaya, Anastasia Ivanova, Ruslan Kalinin, Alexander Manin, Natalya Mikheeva, and Pavel Romodanovsky. "Patient dissatisfaction with medical dental care." In Issues of determining the severity of harm caused to human health as a result of the impact of a biological factor. ru: Publishing Center RIOR, 2020. http://dx.doi.org/10.29039/conferencearticle_5fdcb03a353ad3.76128786.

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The article provides information on the results of studying the materials of 150 commission of forensic medical examinations on the facts of patient dissatisfaction with the provision of medical care. The relevance of the problem of the legal relationship between a doctor and a patient is revealed and shown. The lack of information on these issues leads to a high probability of disputed situations in the providing dental care, so there is an urgent need for an integrated approach to the implementation of legally defined rights of patients. Media coverage of the above-mentioned problems plays an important role in improving the level of legal competence of patients. At the same time, the direct relationship between the doctor and the patient is the most important mechanism for implementing the patient's rights at the dental appointment and preventing conflicts. Behavior of doctors in such cases should be strictly regulated by normative legal acts. The process of information sharing with patients and transfer of information to the patient's relatives should receive in medical preventive institution specific legal basis under sections 30, 31, 48, 61 “Principles of legislation of the Russian Federation about health protection of citizens”, to be fixed in job descriptions with the designation of responsibility.
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Raina, Pranav, Roy J. Primus, Vijayaselvan Jayakar, Dayanand T. Harish, and Aravind Kalavara. "Development of an Empirical Model to Predict Sulfuric Acid Condensate Formation in Air Handling System of Medium Speed Diesel Engines." In ASME 2016 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/imece2016-66547.

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One of the biggest challenges for engines used in Marine industry is to burn fuels of varied compositions, since the vessels often move from regions with highly regulated fuels to regions with no regulations, unlike their on-road and other stationary counterparts. This poses an enormous risk to the performance, reliability, durability and service life of engines that employ exhaust gas recirculation (EGR) as a prime technology to meet stringent emission regulations, laid out by various regulating bodies across the globe like the United States (U.S.) Environmental Protection Agency (EPA) and International Maritime Organization (IMO). Operating on fuels with higher Sulfur content poses a risk of reduced engine component life, due to the formation of concentrated Sulfuric acid (H2SO4), which, if not handled carefully, would lead to higher rates of corrosion on engine parts. Hence, the ability to predict the potential for H2SO4 formation as well its quantity to be handled is essential. This research paper focuses on the development of an empirical model to predict the amount of H2SO4 condensate that can be formed in the air handling system of medium speed diesel engines. The model utilizes a combination of fundamental physics, chemistry, thermodynamics and chemical kinetics. The H2SO4 prediction calculation employs basic measurable parameters from a running engine, such as engine speed, load, EGR flow rate, fuel flow rate, fuel Sulfur concentration to compute a molar balance of hydrocarbon fuel and combustion air quantities along the entire range of engine operation, providing the amount of H2SO4 condensate formed. This is done primarily at EGR cooler, where the recycled exhaust gas gets cooled primarily and the EGR mixer, where it gets cooled further after coming in contact with the charge air and are identified as critical locations.
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10

Baldessar Warmling, Gean Marcos. "An Analysis of Bridges Performance in Southern Brazil Highways." In IABSE Conference, Copenhagen 2018: Engineering the Past, to Meet the Needs of the Future. Zurich, Switzerland: International Association for Bridge and Structural Engineering (IABSE), 2018. http://dx.doi.org/10.2749/copenhagen.2018.330.

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This paper presents the basic concepts of a Bridge Management System that can create a meaningful conservation and maintenance programs for the Brazilian Highway Public system. The methodology, based on a deterministic procedure aims to create a list of priorities towards a future program of maintenance of bridges. This document presents the introduction of a method that includes the content of the analysis. The application of the proposed procedure allowed the analysis of a batch of 308 bridges in the highways systems that cross the states of Parana and Santa Catarina, in the southern part of Brazil. The model considers several aspects that regulate the conditions of those bridges, considering traffic characteristics and maintenance history. The results bring the possibility to relate the actual condition of the structures within the performance that one expects the highway system to provide for the user. In order to complete the analysis, this paper presents a general classification of the bridges, by their performance, creating a very meaningful list of priorities to guide any maintenance program.
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Звіти організацій з теми "Highly regulated basins"

1

Kingston, A. W., A. Mort, C. Deblonde, and O H Ardakani. Hydrogen sulfide (H2S) distribution in the Triassic Montney Formation of the Western Canadian Sedimentary Basin. Natural Resources Canada/CMSS/Information Management, 2021. http://dx.doi.org/10.4095/329266.

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Анотація:
The Montney Formation is a highly productive hydrocarbon reservoir that is of great economic importance to Canada, however production is often dogged by the presence of hydrogen sulfide (H2S), a highly toxic and corrosive gas. Mapping H2S distribution across the Montney basin in the Western Canadian Sedimentary Basin (WCSB) is fundamental to understanding the processes responsible for its occurrence. We derive a Montney-specific dataset of well gas and water geochemistry from the publically available archives of the Alberta Energy Regulator (AER) and British Columbia Oil and Gas Commission (BCOGC) conducting quality assurance and control procedure before spatial interpolation. Empirical Bayesian Kriging is used to interpolate H2S across the whole Montney basin resulting in maps of H2S from hydrocarbon gas, condensates, and water; along with maps of sulfate and chloride ions in water. These interpolations illustrate the heterogeneous distribution of H2S across the basin with the highest concentrations in the Grande Prairie area along with several other isolated regions. Maps of H2S in gas, condensates, and water exhibit similar trends in H2S concentrations, which with future research may help elucidate the origin of H2S in the Montney.
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2

Prusky, Dov, Noel T. Keen, and Stanley Freeman. Elicitation of Preformed Antifungal Compounds by Non-Pathogenic Fungus Mutants and their Use for the Prevention of Postharvest Decay in Avocado Fruits. United States Department of Agriculture, January 1996. http://dx.doi.org/10.32747/1996.7570573.bard.

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C. gloeosporioides attacks unripe avocado fruits in the orchard. Germinated spores produce appressoria that germinate and breach the cuticle, but the resultant subcuticular hyphae become quiescent and do not develop further until fruit is harvested and ripens. Resistance of unripe avocado to attach by C. gloeosporioides is correlated with the presence of fungitoxic concentrations of the preformed antifungal compound, 1-acetoxy-2-hydroxy-4-oxoheneicosa-12, 15 diene in the pericarp of unripe fruits. The objective of this proposal was to study the signal transduction process by which elicitors induce resistance in avocado. It was found that abiotic elicitors, infection of avocado fruit with C. gloeosporioides or treatment of avocado cell suspension with cell-wall elicitor induced a significant production of reactive oxygen species (ROS). Ripe and unripe fruit tissue differ with regard to the ROS production. The unripe, resistant fruit are physiologically able to react and to produce high levels of ROS and increased activity of H+ATPase that can enhance the phenylpropanoid pathway ad regulate the levels of the antifungal compound-diene, inhibit fungal development, resulting in its quiescence. Interestingly, it was also found that growth regulators like cytokinin could do activation of the mechanism of resistance. Postharvest treatments of cytokinins strongly activated the phenylpropanoid pathway and induce resistance. We have developed non-pathogenic strains of C. gloeosporioides by Random Enzyme Mediated Integration and selected a hygromycin resistance, non-pathogenic strain Cg-142 out of 3500 transformants. This non-pathogenic isolate activates H+ATPase and induces resistance against Colletotrichum attack. As a basis for studying the importance of PL in pathogenicity, we have carried out heterologous expression of pel from C. gloeosporioides in the non-pathogenic C. magna and determine the significant increase in pathogenicity of the non-pathogenic strain. Based on these results we can state that pectate lyase is an important pathogenicity factor of C. gloeosporioides and found that fungal pathogenicity is affected not by pel but by PL secretion. Our results suggest that PH regulates the secretion of pectate lyase, and support its importance as a pathogenicity factor during the attack of avocado fruit by C. gloeosporioides . This implicates that if these findings are of universal importance in fungi, control of disease development could be done by regulation of secretion of pathogenicity factors.
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3

DeJaeghere, Joan, Bich-Hang Duong, and Vu Dao. Teaching Practices That Support and Promote Learning: Qualitative Evidence from High and Low Performing Classes in Vietnam. Research on Improving Systems of Education (RISE), January 2021. http://dx.doi.org/10.35489/bsg-rise-ri_2021/024.

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This Insight Note contributes to the growing body of knowledge on teaching practices that foster student learning and achievement by analysing in-depth qualitative data from classroom observations and teacher interviews. Much of the research on teachers and teaching in development literature focuses on observable and quantified factors, including qualifications and training. But simply being qualified (with a university degree in education or subject areas), or trained in certain ways (e.g., coaching versus in-service) explains very little of the variation in learning outcomes (Kane and Staiger, 2008; Wößmann, 2003; Das and Bau, 2020). Teaching is a complex set of practices that draw on teachers’ beliefs about learning, their prior experiences, their content and pedagogical knowledge and repertoire, and their commitment and personality. Recent research in the educational development literature has turned to examining teaching practices, including content knowledge, pedagogical practices, and teacher-student interactions, primarily through quantitative data from knowledge tests and classroom observations of practices (see Bruns, De Gregorio and Taut, 2016; Filmer, Molina and Wane, 2020; Glewwe et al, in progress). Other studies, such as TIMSS, the OECD and a few World Bank studies have used classroom videos to further explain high inference factors of teachers’ (Gallimore and Hiebert, 2000; Tomáš and Seidel, 2013). In this Note, we ask the question: What are the teaching practices that support and foster high levels of learning? Vietnam is a useful case to examine because student learning outcomes based on international tests are high, and most students pass the basic learning levels (Dang, Glewwe, Lee and Vu, 2020). But considerable variation exists between learning outcomes, particularly at the secondary level, where high achieving students will continue to upper-secondary and lower achieving students will drop out at Grade 9 (Dang and Glewwe, 2018). So what differentiates teaching for those who achieve these high learning outcomes and those who don’t? Some characteristics of teachers, such as qualifications and professional commitment, do not vary greatly because most Vietnamese teachers meet the national standards in terms of qualifications (have a college degree) and have a high level of professionalism (Glewwe et al., in progress). Other factors that influence teaching, such as using lesson plans and teaching the national curriculum, are also highly regulated. Therefore, to explain how teaching might affect student learning outcomes, it is important to examine more closely teachers’ practices in the classroom.
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4

Glazer, Itamar, Alice Churchill, Galina Gindin, and Michael Samish. Genomic and Organismal Studies to Elucidate the Mechanisms of Infectivity of Entomopathogenic Fungi to Ticks. United States Department of Agriculture, January 2013. http://dx.doi.org/10.32747/2013.7593382.bard.

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The overall goal of this research was to elucidate the factors affecting early development of Metarhizium spp. (previously named M. anisopliae) on ticks or tick cuticle extracts and the molecular basis of these early infection processes. The original objectives were: 1. Characterize the pre-penetration events (adhesion, germination and appressorium formation) of spores of M. anisopliae strains with high or low virulence during tick infection. 2. Create GFP-expressing strains of M. anisopliae tick pathogens having high and low virulence to compare their progress of infection by microscopy. 3. Use microarray analyses, primarily with existing M. anisopliae EST sequences in GenBank, to identify and characterize fungal genes whose expression is regulated in response to host cuticle extracts. Objective 3 was later modified (as approved by BARD) to use RNAseq to characterize the early stages of fungal gene expression during infection of intact host cuticles. This new method provides a massively larger and more informative dataset and allows us to take advantage of a) recently published genomes of Metarhizium robertsii and M. acridum for RNAseq data analysis, and b) newly developed and highly efficient cDNA sequencing technologies that are relatively low cost and, therefore, allow deep sequencing of multiple transcriptome samples. We examined pre-penetration and penetration events that differentiate high and low virulence strains of Metarhizium spp., focusing on spore adhesion, germination, appressorium formation, and penetration of tick integuments. Initiation of fungal infection was compared on susceptible and resistant tick species at different tick developmental stages. In vitro studies comparing the effects of protein and fatty acid profiles from tick cuticle extracts demonstrated that resistant tick cuticles contain higher concentrations of specific lipids that inhibit fungal development than do susceptible tick cuticles, suggesting one mechanism of Ixodidae resistance to fungal entomopathogens (Objective 1). We used molecular markers to determine that the three M. anisopliae strains from Israel that we studied actually were three distinct species. M. brunneum is highly virulent against the tick Rhipicephalus annulatus, M. pingshaense and M. robertsii are intermediate in virulence, and M. majus is of low virulence. We transformed all four Metarhizium species to express GFP and used them in pathogenicity assays against diverse tick species. Key findings were that a) resistant ticks inhibit Metarhizium infection prior to hemocoel invasion by reducing fungal viability on the cuticle surface (Objective 2), as was supported by the in vitro studies of Objective 1, and b) Metarhizium kills susceptible ticks after cuticle penetration but prior to hemocoel colonization. Transcriptome studies of the most virulent species, M. brunneum, are in progress and include analyses of ungerminated conidia and conidia germination and development on a low nutrient medium or on susceptible R. annulatus exoskeleton (Objective 3). We anticipate these studies will contribute to identifying fungal genetic factors that increase virulence and speed of kill and may help reveal tick chemistries that could be included in biocontrol formulations to increase efficacy. Methodologies developed to screen tick cuticle extracts for ability to support conidia germination and development may help in the selection of wild fungi with increased virulence against resistant ticks. The overall knowledge gained should contribute not only to the improvement of tick control but also to the control of other blood-sucking arthropods and related plant pests. Use of bio-based agents for controlling arthropods will contribute to a healthier, more sustainable environment and serve a growing number of organic food farmers.
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5

Rafaeli, Ada, Russell Jurenka, and Chris Sander. Molecular characterisation of PBAN-receptors: a basis for the development and screening of antagonists against Pheromone biosynthesis in moth pest species. United States Department of Agriculture, January 2008. http://dx.doi.org/10.32747/2008.7695862.bard.

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Анотація:
The original objectives of the approved proposal included: (a) The determination of species- and tissue-specificity of the PBAN-R; (b) the elucidation of the role of juvenile hormone in gene regulation of the PBAN-R; (c) the identificationof the ligand binding domains in the PBAN-R and (d) the development of efficient screening assays in order to screen potential antagonists that will block the PBAN-R. Background to the topic: Moths constitute one of the major groups of pest insects in agriculture and their reproductive behavior is dependent on chemical communication. Sex-pheromone blends are utilised by a variety of moth species to attract conspecific mates. In most of the moth species sex-pheromone biosynthesis is under circadian control by the neurohormone, PBAN (pheromone-biosynthesis-activating neuropeptide). In order to devise ideal strategies for mating disruption/prevention, we proposed to study the interactions between PBAN and its membrane-bound receptor in order to devise potential antagonists. Major conclusions: Within the framework of the planned objectives we have confirmed the similarities between the two Helicoverpa species: armigera and zea. Receptor sequences of the two Helicoverpa spp. are 98% identical with most changes taking place in the C-terminal. Our findings indicate that PBAN or PBAN-like receptors are also present in the neural tissues and may represent a neurotransmitter-like function for PBAN-like peptides. Surprisingly the gene encoding the PBAN-receptor was also present in the male homologous tissue, but it is absent at the protein level. The presence of the receptor (at the gene- and protein-levels), and the subsequent pheromonotropic activity are age-dependent and up-regulated by Juvenile Hormone in pharate females but down-regulated by Juvenile Hormone in adult females. Lower levels of pheromonotropic activity were observed when challenged with pyrokinin-like peptides than with HezPBAN as ligand. A model of the 3D structure of the receptor was created using the X-ray structure of rhodopsin as a template after sequence alignment of the HezPBAN-R with several other GPCRs and computer simulated docking with the model predicted putative binding sites. Using in silico mutagenesis the predicted docking model was validated with experimental data obtained from expressed chimera receptors in Sf9 cells created by exchanging between the three extracellular loops of the HezPBAN-R and the Drosophila Pyrokinin-R (CG9918). The chimera receptors also indicated that the 3ʳᵈ extracellular loop is important for recognition of PBAN or Diapause hormone ligands. Implications: The project has successfully completed all the objectives and we are now in a position to be able to design and screen potential antagonists for pheromone production. The successful docking simulation-experiments encourage the use of in silico experiments for initial (high-throughput) screening of potential antagonists. However, the differential responses between the expressed receptor (Sf9 cells) and the endogenous receptor (pheromone glands) emphasize the importance of assaying lead compounds using several alternative bioassays (at the cellular, tissue and organism levels). The surprising discovery of the presence of the gene encoding the PBAN-R in the male homologous tissue, but its absence at the protein level, launches opportunities for studying molecular regulation pathways and the evolution of these GPCRs. Overall this research will advance research towards the goal of finding antagonists for this important class of receptors that might encompass a variety of essential insect functions.
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6

El Halawani, Mohamed, and Israel Rozenboim. Temperature Stress and Turkey Reproduction. United States Department of Agriculture, May 2002. http://dx.doi.org/10.32747/2002.7570546.bard.

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High temperature stress is of major concern to turkey producers in Israel and the United States. The decline in the rate of egg production at high environmental temperature is well recognized, but the neuroendocrinological basis is not understood. Our objectives were: 1) to characterize the hypothalamo-hypophyseal axis involvement in the mechanism(s) underlying the detrimental effect of heat stress on reproduction, and 2) to establish procedures that alleviate the damaging effect of heat stress on reproduction. Heat stress (40oC, Israel; 32oC, U.S.) caused significant reduction in egg production, which was restored by VIP immunoneutralization. The decline in egg production did not appear to be entirely related to the expression of incubation behavior due to the rise in circulating PRL in stressed birds. Heat stress was found to increase circulating PRL in ovariectomized turkeys independent of the reproductive stage. Active immunization against VIP was shown for the first time to up-regulate LHb and FSHb subunit mRNA contents. These findings taken together with the results that the heat stress-induced decline in egg production may not be dependent upon the reproductive stage, lead to the suggestion that the detrimental effect of heat stress on reproductive performance may be in part mediated by VIP acting directly on the GnRH/gonadotropin system. Inhibin (INH) immunoneutralization has been shown to enhance FSH secretion and induces ovulation in mammals. It is hypothesized that immunization of heat-stressed turkeys against INH will increase levels of circulating FSH and the number of preovulating follicles which leads to improved reproductive performance. We have cloned and expressed turkey INH-a and INH-bA. Active immunization of turkey hens with rtINH-a increased pituitary FSH-b subunit mRNA and the number of non-graded preovulatory yellow follicles, but no significant increase in egg production was observed.
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7

Horwitz, Benjamin A., and Barbara Gillian Turgeon. Fungal Iron Acquisition, Oxidative Stress and Virulence in the Cochliobolus-maize Interaction. United States Department of Agriculture, March 2012. http://dx.doi.org/10.32747/2012.7709885.bard.

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Анотація:
Our project focused on genes for high affinity iron acquisition in Cochliobolus heterostrophus, a necrotrophic pathogen of maize, and their intertwined relationship to oxidative stress status and virulence of the fungus on the host. An intriguing question was why mutants lacking the nonribosomal peptide synthetase (NRPS) gene (NPS6) responsible for synthesis of the extracellular siderophore, coprogen, are sensitive to oxidative stress. Our overall objective was to understand the mechanistic connection between iron stress and oxidative stress as related to virulence of a plant pathogen to its host. The first objective was to examine the interface where small molecule peptide and reactive oxygen species (ROS) mechanisms overlap. The second objective was to determine if the molecular explanation for common function is common signal transduction pathways. These pathways, built around sensor kinases, response regulators, and transcription factors may link sequestering of iron, production of antioxidants, resistance to oxidative stress, and virulence. We tested these hypotheses by genetic manipulation of the pathogen, virulence assays on the host plant, and by following the expression of key fungal genes. An addition to the original program, made in the first year, was to develop, for fungi, a genetically encoded indicator of redox state based on the commercially available Gfp-based probe pHyper, designed for animal cell biology. We implemented several tools including a genetically encoded indicator of redox state, a procedure to grow iron-depleted plants, and constructed a number of new mutants in regulatory genes. Lack of the major Fe acquisition pathways results in an almost completely avirulent phenotype, showing how critical Fe acquisition is for the pathogen to cause disease. Mutants in conserved signaling pathways have normal ability to regulate NPS6 in response to Fe levels, as do mutants in Lae1 and Vel1, two master regulators of gene expression. Vel1 mutants are sensitive to oxidative stress, and the reason may be underexpression of a catalase gene. In nps6 mutants, CAT3 is also underexpressed, perhaps explaining the sensitivity to oxidative stress. We constructed a deletion mutant for the Fe sensor-regulator SreA and found that it is required for down regulation of NPS6 under Fe-replete conditions. Lack of SreA, though, did not make the fungus over-sensitive to ROS, though the mutant had a slow growth rate. This suggests that overproduction of siderophore under Fe-replete conditions is not very damaging. On the other hand, increasing Fe levels protected nps6 mutants from inhibition by ROS, implying that Fe-catalyzed Fenton reactions are not the main factor in its sensitivity to ROS. We have made some progress in understanding why siderophore mutants are sensitive to oxidative stress, and in doing so, defined some novel regulatory relationships. Catalase genes, which are not directly related to siderophore biosynthesis, are underexpressed in nps6 mutants, suggesting that the siderophore product (with or without bound Fe) may act as a signal. Siderophores, therefore, could be a target for intervention in the field, either by supplying an incorrect signal or blocking a signal normally provided during infection. We already know that nps6 mutants cause smaller lesions and have difficulty establishing invasive growth in the host. Lae1 and Vel1 are the first factors shown to regulate both super virulence conferred by T-toxin, and basic pathogenicity, due to unknown factors. The mutants are also altered in oxidative stress responses, key to success in the infection court, asexual and sexual development, essential for fungal dissemination in the field, aerial hyphal growth, and pigment biosynthesis, essential for survival in the field. Mutants in genes encoding NADPH oxidase (Nox) are compromised in development and virulence. Indeed the triple mutant, which should lack all Nox activity, was nearly avirulent. Again, gene expression experiments provided us with initial evidence that superoxide produced by the fungus may be most important as a signal. Blocking oxidant production by the pathogen may be a way to protect the plant host, in interactions with necrotrophs such as C. heterostrophus which seem to thrive in an oxidant environment.
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8

Pawlowski, Wojtek P., and Avraham A. Levy. What shapes the crossover landscape in maize and wheat and how can we modify it. United States Department of Agriculture, January 2015. http://dx.doi.org/10.32747/2015.7600025.bard.

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Анотація:
Meiotic recombination is a process in which homologous chromosomes engage in the exchange of DNA segments, creating gametes with new genetic makeup and progeny with new traits. The genetic diversity generated in this way is the main engine of crop improvement in sexually reproducing plants. Understanding regulation of this process, particularly the regulation of the rate and location of recombination events, and devising ways of modifying them, was the major motivation of this project. The project was carried out in maize and wheat, two leading crops, in which any advance in the breeder’s toolbox can have a huge impact on food production. Preliminary work done in the USA and Israeli labs had established a strong basis to address these questions. The USA lab pioneered the ability to map sites where recombination is initiated via the induction of double-strand breaks in chromosomal DNA. It has a long experience in cytological analysis of meiosis. The Israeli lab has expertise in high resolution mapping of crossover sites and has done pioneering work on the importance of epigenetic modifications for crossover distribution. It has identified genes that limit the rates of recombination. Our working hypothesis was that an integrative analysis of double-strand breaks, crossovers, and epigenetic data will increase our understanding of how meiotic recombination is regulated and will enhance our ability to manipulate it. The specific objectives of the project were: To analyze the connection between double-strand breaks, crossover, and epigenetic marks in maize and wheat. Protocols developed for double-strand breaks mapping in maize were applied to wheat. A detailed analysis of existing and new data in maize was conducted to map crossovers at high resolution and search for DNA sequence motifs underlying crossover hotspots. Epigenetic modifications along maize chromosomes were analyzed as well. Finally, a computational analysis tested various hypotheses on the importance of chromatin structure and specific epigenetic modifications in determining the locations of double-strand breaks and crossovers along chromosomes. Transient knockdowns of meiotic genes that suppress homologous recombination were carried out in wheat using Virus-Induced Gene Silencing. The target genes were orthologs of FANCM, DDM1, MET1, RECQ4, and XRCC2.
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9

Vargas-Herrera, Hernando, Juan Jose Ospina-Tejeiro, Carlos Alfonso Huertas-Campos, Adolfo León Cobo-Serna, Edgar Caicedo-García, Juan Pablo Cote-Barón, Nicolás Martínez-Cortés, et al. Monetary Policy Report - April de 2021. Banco de la República de Colombia, July 2021. http://dx.doi.org/10.32468/inf-pol-mont-eng.tr2-2021.

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Анотація:
1.1 Macroeconomic summary Economic recovery has consistently outperformed the technical staff’s expectations following a steep decline in activity in the second quarter of 2020. At the same time, total and core inflation rates have fallen and remain at low levels, suggesting that a significant element of the reactivation of Colombia’s economy has been related to recovery in potential GDP. This would support the technical staff’s diagnosis of weak aggregate demand and ample excess capacity. The most recently available data on 2020 growth suggests a contraction in economic activity of 6.8%, lower than estimates from January’s Monetary Policy Report (-7.2%). High-frequency indicators suggest that economic performance was significantly more dynamic than expected in January, despite mobility restrictions and quarantine measures. This has also come amid declines in total and core inflation, the latter of which was below January projections if controlling for certain relative price changes. This suggests that the unexpected strength of recent growth contains elements of demand, and that excess capacity, while significant, could be lower than previously estimated. Nevertheless, uncertainty over the measurement of excess capacity continues to be unusually high and marked both by variations in the way different economic sectors and spending components have been affected by the pandemic, and by uneven price behavior. The size of excess capacity, and in particular the evolution of the pandemic in forthcoming quarters, constitute substantial risks to the macroeconomic forecast presented in this report. Despite the unexpected strength of the recovery, the technical staff continues to project ample excess capacity that is expected to remain on the forecast horizon, alongside core inflation that will likely remain below the target. Domestic demand remains below 2019 levels amid unusually significant uncertainty over the size of excess capacity in the economy. High national unemployment (14.6% for February 2021) reflects a loose labor market, while observed total and core inflation continue to be below 2%. Inflationary pressures from the exchange rate are expected to continue to be low, with relatively little pass-through on inflation. This would be compatible with a negative output gap. Excess productive capacity and the expectation of core inflation below the 3% target on the forecast horizon provide a basis for an expansive monetary policy posture. The technical staff’s assessment of certain shocks and their expected effects on the economy, as well as the presence of several sources of uncertainty and related assumptions about their potential macroeconomic impacts, remain a feature of this report. The coronavirus pandemic, in particular, continues to affect the public health environment, and the reopening of Colombia’s economy remains incomplete. The technical staff’s assessment is that the COVID-19 shock has affected both aggregate demand and supply, but that the impact on demand has been deeper and more persistent. Given this persistence, the central forecast accounts for a gradual tightening of the output gap in the absence of new waves of contagion, and as vaccination campaigns progress. The central forecast continues to include an expected increase of total and core inflation rates in the second quarter of 2021, alongside the lapse of the temporary price relief measures put in place in 2020. Additional COVID-19 outbreaks (of uncertain duration and intensity) represent a significant risk factor that could affect these projections. Additionally, the forecast continues to include an upward trend in sovereign risk premiums, reflected by higher levels of public debt that in the wake of the pandemic are likely to persist on the forecast horizon, even in the context of a fiscal adjustment. At the same time, the projection accounts for the shortterm effects on private domestic demand from a fiscal adjustment along the lines of the one currently being proposed by the national government. This would be compatible with a gradual recovery of private domestic demand in 2022. The size and characteristics of the fiscal adjustment that is ultimately implemented, as well as the corresponding market response, represent another source of forecast uncertainty. Newly available information offers evidence of the potential for significant changes to the macroeconomic scenario, though without altering the general diagnosis described above. The most recent data on inflation, growth, fiscal policy, and international financial conditions suggests a more dynamic economy than previously expected. However, a third wave of the pandemic has delayed the re-opening of Colombia’s economy and brought with it a deceleration in economic activity. Detailed descriptions of these considerations and subsequent changes to the macroeconomic forecast are presented below. The expected annual decline in GDP (-0.3%) in the first quarter of 2021 appears to have been less pronounced than projected in January (-4.8%). Partial closures in January to address a second wave of COVID-19 appear to have had a less significant negative impact on the economy than previously estimated. This is reflected in figures related to mobility, energy demand, industry and retail sales, foreign trade, commercial transactions from selected banks, and the national statistics agency’s (DANE) economic tracking indicator (ISE). Output is now expected to have declined annually in the first quarter by 0.3%. Private consumption likely continued to recover, registering levels somewhat above those from the previous year, while public consumption likely increased significantly. While a recovery in investment in both housing and in other buildings and structures is expected, overall investment levels in this case likely continued to be low, and gross fixed capital formation is expected to continue to show significant annual declines. Imports likely recovered to again outpace exports, though both are expected to register significant annual declines. Economic activity that outpaced projections, an increase in oil prices and other export products, and an expected increase in public spending this year account for the upward revision to the 2021 growth forecast (from 4.6% with a range between 2% and 6% in January, to 6.0% with a range between 3% and 7% in April). As a result, the output gap is expected to be smaller and to tighten more rapidly than projected in the previous report, though it is still expected to remain in negative territory on the forecast horizon. Wide forecast intervals reflect the fact that the future evolution of the COVID-19 pandemic remains a significant source of uncertainty on these projections. The delay in the recovery of economic activity as a result of the resurgence of COVID-19 in the first quarter appears to have been less significant than projected in the January report. The central forecast scenario expects this improved performance to continue in 2021 alongside increased consumer and business confidence. Low real interest rates and an active credit supply would also support this dynamic, and the overall conditions would be expected to spur a recovery in consumption and investment. Increased growth in public spending and public works based on the national government’s spending plan (Plan Financiero del Gobierno) are other factors to consider. Additionally, an expected recovery in global demand and higher projected prices for oil and coffee would further contribute to improved external revenues and would favor investment, in particular in the oil sector. Given the above, the technical staff’s 2021 growth forecast has been revised upward from 4.6% in January (range from 2% to 6%) to 6.0% in April (range from 3% to 7%). These projections account for the potential for the third wave of COVID-19 to have a larger and more persistent effect on the economy than the previous wave, while also supposing that there will not be any additional significant waves of the pandemic and that mobility restrictions will be relaxed as a result. Economic growth in 2022 is expected to be 3%, with a range between 1% and 5%. This figure would be lower than projected in the January report (3.6% with a range between 2% and 6%), due to a higher base of comparison given the upward revision to expected GDP in 2021. This forecast also takes into account the likely effects on private demand of a fiscal adjustment of the size currently being proposed by the national government, and which would come into effect in 2022. Excess in productive capacity is now expected to be lower than estimated in January but continues to be significant and affected by high levels of uncertainty, as reflected in the wide forecast intervals. The possibility of new waves of the virus (of uncertain intensity and duration) represents a significant downward risk to projected GDP growth, and is signaled by the lower limits of the ranges provided in this report. Inflation (1.51%) and inflation excluding food and regulated items (0.94%) declined in March compared to December, continuing below the 3% target. The decline in inflation in this period was below projections, explained in large part by unanticipated increases in the costs of certain foods (3.92%) and regulated items (1.52%). An increase in international food and shipping prices, increased foreign demand for beef, and specific upward pressures on perishable food supplies appear to explain a lower-than-expected deceleration in the consumer price index (CPI) for foods. An unexpected increase in regulated items prices came amid unanticipated increases in international fuel prices, on some utilities rates, and for regulated education prices. The decline in annual inflation excluding food and regulated items between December and March was in line with projections from January, though this included downward pressure from a significant reduction in telecommunications rates due to the imminent entry of a new operator. When controlling for the effects of this relative price change, inflation excluding food and regulated items exceeds levels forecast in the previous report. Within this indicator of core inflation, the CPI for goods (1.05%) accelerated due to a reversion of the effects of the VAT-free day in November, which was largely accounted for in February, and possibly by the transmission of a recent depreciation of the peso on domestic prices for certain items (electric and household appliances). For their part, services prices decelerated and showed the lowest rate of annual growth (0.89%) among the large consumer baskets in the CPI. Within the services basket, the annual change in rental prices continued to decline, while those services that continue to experience the most significant restrictions on returning to normal operations (tourism, cinemas, nightlife, etc.) continued to register significant price declines. As previously mentioned, telephone rates also fell significantly due to increased competition in the market. Total inflation is expected to continue to be affected by ample excesses in productive capacity for the remainder of 2021 and 2022, though less so than projected in January. As a result, convergence to the inflation target is now expected to be somewhat faster than estimated in the previous report, assuming the absence of significant additional outbreaks of COVID-19. The technical staff’s year-end inflation projections for 2021 and 2022 have increased, suggesting figures around 3% due largely to variation in food and regulated items prices. The projection for inflation excluding food and regulated items also increased, but remains below 3%. Price relief measures on indirect taxes implemented in 2020 are expected to lapse in the second quarter of 2021, generating a one-off effect on prices and temporarily affecting inflation excluding food and regulated items. However, indexation to low levels of past inflation, weak demand, and ample excess productive capacity are expected to keep core inflation below the target, near 2.3% at the end of 2021 (previously 2.1%). The reversion in 2021 of the effects of some price relief measures on utility rates from 2020 should lead to an increase in the CPI for regulated items in the second half of this year. Annual price changes are now expected to be higher than estimated in the January report due to an increased expected path for fuel prices and unanticipated increases in regulated education prices. The projection for the CPI for foods has increased compared to the previous report, taking into account certain factors that were not anticipated in January (a less favorable agricultural cycle, increased pressure from international prices, and transport costs). Given the above, year-end annual inflation for 2021 and 2022 is now expected to be 3% and 2.8%, respectively, which would be above projections from January (2.3% and 2,7%). For its part, expected inflation based on analyst surveys suggests year-end inflation in 2021 and 2022 of 2.8% and 3.1%, respectively. There remains significant uncertainty surrounding the inflation forecasts included in this report due to several factors: 1) the evolution of the pandemic; 2) the difficulty in evaluating the size and persistence of excess productive capacity; 3) the timing and manner in which price relief measures will lapse; and 4) the future behavior of food prices. Projected 2021 growth in foreign demand (4.4% to 5.2%) and the supposed average oil price (USD 53 to USD 61 per Brent benchmark barrel) were both revised upward. An increase in long-term international interest rates has been reflected in a depreciation of the peso and could result in relatively tighter external financial conditions for emerging market economies, including Colombia. Average growth among Colombia’s trade partners was greater than expected in the fourth quarter of 2020. This, together with a sizable fiscal stimulus approved in the United States and the onset of a massive global vaccination campaign, largely explains the projected increase in foreign demand growth in 2021. The resilience of the goods market in the face of global crisis and an expected normalization in international trade are additional factors. These considerations and the expected continuation of a gradual reduction of mobility restrictions abroad suggest that Colombia’s trade partners could grow on average by 5.2% in 2021 and around 3.4% in 2022. The improved prospects for global economic growth have led to an increase in current and expected oil prices. Production interruptions due to a heavy winter, reduced inventories, and increased supply restrictions instituted by producing countries have also contributed to the increase. Meanwhile, market forecasts and recent Federal Reserve pronouncements suggest that the benchmark interest rate in the U.S. will remain stable for the next two years. Nevertheless, a significant increase in public spending in the country has fostered expectations for greater growth and inflation, as well as increased uncertainty over the moment in which a normalization of monetary policy might begin. This has been reflected in an increase in long-term interest rates. In this context, emerging market economies in the region, including Colombia, have registered increases in sovereign risk premiums and long-term domestic interest rates, and a depreciation of local currencies against the dollar. Recent outbreaks of COVID-19 in several of these economies; limits on vaccine supply and the slow pace of immunization campaigns in some countries; a significant increase in public debt; and tensions between the United States and China, among other factors, all add to a high level of uncertainty surrounding interest rate spreads, external financing conditions, and the future performance of risk premiums. The impact that this environment could have on the exchange rate and on domestic financing conditions represent risks to the macroeconomic and monetary policy forecasts. Domestic financial conditions continue to favor recovery in economic activity. The transmission of reductions to the policy interest rate on credit rates has been significant. The banking portfolio continues to recover amid circumstances that have affected both the supply and demand for loans, and in which some credit risks have materialized. Preferential and ordinary commercial interest rates have fallen to a similar degree as the benchmark interest rate. As is generally the case, this transmission has come at a slower pace for consumer credit rates, and has been further delayed in the case of mortgage rates. Commercial credit levels stabilized above pre-pandemic levels in March, following an increase resulting from significant liquidity requirements for businesses in the second quarter of 2020. The consumer credit portfolio continued to recover and has now surpassed February 2020 levels, though overall growth in the portfolio remains low. At the same time, portfolio projections and default indicators have increased, and credit establishment earnings have come down. Despite this, credit disbursements continue to recover and solvency indicators remain well above regulatory minimums. 1.2 Monetary policy decision In its meetings in March and April the BDBR left the benchmark interest rate unchanged at 1.75%.
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Or, Etti, Tai-Ping Sun, Amnon Lichter, and Avichai Perl. Characterization and Manipulation of the Primary Components in Gibberellin Signaling in the Grape Berry. United States Department of Agriculture, January 2010. http://dx.doi.org/10.32747/2010.7592649.bard.

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Анотація:
Seedless cultivars dominate the table grape industry. In these cultivars it is mandatory to apply gibberellin (GA) to stimulate berry development to a commercially acceptable size. These cultivars differ in their sensitivity to GA application, and it frequently results in adverse effects such as decreased bud fertility and increased fruit drop. Our long term goals are to (1) understand the molecular basis for the differential sensitivity and identify markers for selection of sensitive cultivars (2) to develop new strategies for targeted manipulation of the grape berry response to GA that will eliminate the need in GA application and the undesirable effects of GA on the vine, while maintaining its desirable effects on the berry. Both strategies are expected to reduce production cost and meet growing consumer demand for reduced use of chemicals. This approach relies on a comprehensive characterization of the central components in the GA signaling cascade in the berry. Several key components in the GA signaling pathway were identified in Arabidopsis and rice, including the GA receptors, GID1s, and a family of DELLA proteins that are the major negative regulators of the GA response. GA activates its response pathway by binding to GID1s, which then target DELLAs for degradation via interaction with SLY, a DELLA specific F-box protein. In grape, only one DELLA gene was characterized prior to this study, which plays a major role in inhibiting GA-promoted stem growth and GA-repressed floral induction but it does not regulate fruit growth. Therefore, we speculated that other DELLA family member(s) may control GA responses in berry, and their identification and manipulation may result in GA-independent berry growth. In the current study we isolated two additional VvDELLA family members, two VvGID1 genes and two VvSLY genes. Arabidopsis anti-AtRGA polyclonal antibodies recognized all three purified VvDELLA proteins, but its interaction with VvDELLA3 was weaker. Overexpression of the VvDELLAs, the VvGID1s, and the VvSLYs in the Arabidopsis mutants ga1-3/rga-24, gid1a-2/1c-2 and sly1-10, respectively, rescued the various mutant phenotypes. In vitro GAdependent physical interaction was shown between the VvDELLAs and the VvGID1s, and GAindependent interaction was shown between the VvDELLAs and VvSLYs. Interestingly, VvDELLA3 did not interact with VvGID1b. Together, the results indicate that the identified grape homologs serve as functional DELLA repressors, receptors and DELLA-interacting F-box proteins. Expression analyses revealed that (1) VvDELLA2 was expressed in all the analyzed tissues and was the most abundant (2) VvDELLA1 was low expressed in berries, confirming former study (3) Except in carpels and very young berries, VvDELLA3 levels were the lowest in most tissues. (4) Expression of both VvGID1s was detected in all the grape tissues, but VvGID1b transcript levels were significantly higher than VvGID1a. (5) In general, both VvDELLAs and VvGID1s transcripts levels increased as tissues aged. Unfertilized and recently fertilized carpels did not follow this trend, suggesting different regulatory mechanism of GA signaling in these stages. Characterization of the response to GA of various organs in three seedless cultivars revealed differential response of the berries and rachis. Interestingly, VvDELLA3 transcript levels in the GA-unresponsive berries of cv. Spring blush were significantly higher compared to their levels in the highly responsive berries of cv. Black finger. Assuming that VvDELLA2 and VvDELLA3 are regulating berry size, constructs carrying potential dominant mutations in each gene were created. Furthermore, constitutive silencing of these genes by mIR is underway, to reveal the effect of each gene on the berry phenotype.
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