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5642. Coordinated variation between veins and stomata in cotton and its relationship with water-use efficiency under drought stress
- Creator:
- Lei, Z. Y., Han, J. M., Yi, X. P., Zhang, W. F., and Zhang, Y. L.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- fotosyntéza, photosynthesis, major leaf veins, maximum stomatal conductance, minor leaf veins, stomata size, 2, and 581
- Language:
- Multiple languages
- Description:
- Drought stress causes changes in vein and stomatal density. The objectives of this study were to determine (1) if the changes in vein and stomatal density are coordinated in cotton (Gossypium hirsutum L.) and (2) how these changes affect water-use efficiency (WUE). The results showed significant positive correlations between vein density and stomatal density when cotton was grown under different degrees of drought stress. WUE was significantly positively correlated with the densities of both veins and stomata. Stomatal pore area and stomatal density on the abaxial leaf side, but not the adaxial side, were significantly correlated with WUE, stomatal conductance, leaf net photosynthetic rate, and transpiration rate. In conclusion, coordinated changes in vein and stomatal density improve the WUE of cotton under drought stress. The abaxial leaf side plays a more important role than the adaxial side in WUE and gas exchange., Z. Y. Lei, J. M. Han, X. P. Yi, W. F. Zhang, Y. L. Zhang., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
5643. Coordination control and analysis of TCSC devices to protect electrical power systems against disruptive disturbances
- Creator:
- Wang, Zhaoxu, Zhai, Chao, Zhang, Hehong, Xiao, Gaoxi, Chen, Guanghou, and Xu, Yulin
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- coordination control, thyristor-controlled series compensation(TCSC), power systems, and disruptive disturbances
- Language:
- English
- Description:
- In this work, we study coordination control and effective deployment of thyristor-controlled series compensation (TCSC) to protect power grids against disruptive disturbances. The power grid consists of flexible alternate current transmission systems (FACTS) devices for regulating power flow, phasor measurement units (PMUs) for detecting system states, and control station for generating the regulation signals. We propose a novel coordination control approach of TCSC devices to change branch impedance and regulate the power flow against unexpected disturbances on buses or branches. More significantly, a numerical method is developed to estimate a gradient vector for generating regulation signals of TCSC devices and reducing computational costs. To describe the degree of power system stress, a performance index is designed based on the error between the desired power flow and actual values. Moreover, technical analysis is presented to ensure the convergence of the proposed coordination control algorithm. Numerical simulations are implemented to substantiate that the coordination control approach can effectively alleviate the stress caused by contingencies on IEEE 24 bus system, as compared to the classic PID control. It is also demonstrated that the deployment of TCSCs can alleviate the system stress greatly by considering both impedance magnitude and active power on branches.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
5644. Copies of lnp’S uniformly in the spaces 2(C[0,1],X) and 1(C[0,1],X)
- Creator:
- Popa, Dumitru
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- matematika, mathematics, average, multiplication operator, p-summing linear operators, copies of ln p’s uniformly, local structure of a Banach space, 13, and 51
- Language:
- English
- Description:
- We study the presence of copies of ln p ’s uniformly in the spaces 2(C[0, 1],X) and 1(C[0, 1],X). By using Dvoretzky’s theorem we deduce that if X is an infinite- dimensional Banach space, then 2(C[0, 1],X) contains p2-uniformly copies of ln∞’s and 1(C[0, 1],X) contains -uniformly copies of ln 2 ’s for all > 1. As an application, we show that if X is an infinite-dimensional Banach space then the spaces 2(C[0, 1],X) and 1(C[0, 1],X) are distinct, extending the well-known result that the spaces 2(C[0, 1],X) and N(C[0, 1],X) are distinct., Dumitru Popa., and Seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
5645. Copper-induced changes in reproductive functions: in vivo and in vitro effects
- Creator:
- Roychoudhury, S., Nath, S., Peter Massányi, Stawarz, R., Kacaniova, M., and Kolesarova, A.
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, měď, copper, effect, reproductive function, in vivo, in vitro, nanotoxicity, 14, and 612
- Language:
- English
- Description:
- The goal of this study is to summarize the current knowledge on the effects of one of the essential metals, copper (Cu) on the reproductive system. The development of past four decades addressing effects of Cu on reproductive organs is reviewed. The most relevant data obtained from in vivo and in vitro experiments performed on humans and other mammals, including effects of copper nanoparticles (CuNPs) on the reproductive functions are presented. Short term Cu admi nistration has been found to exert deleterious effect on intracellular organelles of rat ovarian cells in vivo . In vitro administration in porcine ovarian granulosa cells releases insulin-like growth factor (IGF-I), steroid hormone progesterone (P4), and induces expression of peptides related to proliferation and apoptosis. Adverse effect of Cu on male reproductive functions has been indicated by the decrease in spermatozoa parameters such as concentration, viability and motility. Copper nanoparticles are capable of generating oxidative stress in vitro thereby leading to reproductive toxicity. Toxic effect of CuNPs has been evident more in male mice than in females. Even though further investigations are necessary to arrive at a definitive conclusion, Cu notably influences the reproductive functions by interfering with both male and female reproductive systems and also hampers embryo development in dose-dependent manner., S. Roychoudhury, S. Nath, P. Massanyi, R. Stawarz, M. Kacaniova, A. Kolesarova., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
5646. Copula approach to residuals of regime-switching models
- Creator:
- Petričková, Anna and Komorníková, Magda
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- autocopula, timeseries, residuals, and regime-switching models
- Language:
- English
- Description:
- The autocorrelation function describing the linear dependence is not suitable for description of residual dependence of the regime-switching models. In this contribution, inspired by Rakonczai (\cite{Rak09}), we will model the residual dependence of the regime-switching models (SETAR, LSTAR and ESTAR) with the autocopulas (Archimedean, EV and their convex combinations) and construct improved quality models for the original real time series.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
5647. Copulas with given values on a horizontal and a vertical section
- Creator:
- Durante, Fabrizio, Kolesárová, Anna, Mesiar, Radko, and Sempi, Carlo
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- copula, horizontal section, vertical section, and binary aggregation operator
- Language:
- English
- Description:
- n this paper we study the set of copulas for which both a horizontal section and a vertical section have been given. We give a general construction for copulas of this type and we provide the lower and upper copulas with these sections. Symmetric copulas with given horizontal section are also discussed, as well as copulas defined on a grid of the unit square. Several examples are presented.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
5648. Copyrolysis of coal / waste polymers mixturest
- Creator:
- Kříž, Vlastimil and Brožová, Zuzana
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Geologie. Meteorologie. Klimatologie, uhlí, bavlna, pneumatiky, plasty, coal, cotton, tires, plastics, co-pyrolysis, wastes, 7, and 551
- Language:
- English
- Description:
- Mixtures of coal/waste tires, coal/waste plastics and coal/waste cotton were pyrolyzed in the laboratory pyrolytical unit built in IRSM AS CR Prague. Non-caking hard coal (mine Lazy) and its mixtures with some organic wastes were pyrolyzed in a quartz reactor inserted in a vertical tube furnace. The main product yields (coke, tar, gas and reaction water) documented exhibit entirely different influence of added waste. Results demonstrated that co-pyrolysis is meaning full in case of waste tiers and plastics. However, in case of co-processing with waste cotton (natural textile), the results are not promising., Vlastimil Kříž and Zuzana Brožová., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
5649. Cordatus Bohemus Stanislav Vydra
- Creator:
- Kraus, Ivo
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- matematici, univerzitní profesoři, Stanislav Vydra, mathematicians, and university professors
- Language:
- Czech
- Description:
- Ivo Kraus.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
5650. CORDIS propojuje vědce a inovátory ve znalostní ekonomice
- Creator:
- Vosečková, Anna
- Format:
- print, bez média, and svazek
- Type:
- article, rozhovory, model:article, and TEXT
- Subject:
- Věda. Všeobecnosti. Základy vědy a kultury. Vědecká práce, Lebaube, Philippe, Evropská komise., Community Research and Development Information Service, výzkum a vývoj, služby, research and development, service industries, 12, and 00
- Language:
- Czech
- Description:
- In this issue, we feature an interview with Phillipe Lebaube, head of the CORDIS Unit of EU’s Publication, for a detailed view on its activities. CORDIS, information space devoted to European research and development and technology transfer, has been in operation for nearly two decades now. and Anna Vosečková.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public