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901.
Catarina C. V. Oliveira Elvira Fatsini Ignacio Fernndez Catarina Anjos Franois Chauvign Joan Cerd Robin Mjelle Jorge M. O. Fernandes Elsa Cabrita 《International journal of molecular sciences》2020,21(23)
Kisspeptin regulates puberty and reproduction onset, acting upstream of the brain–pituitary–gonad (HPG) axis. This study aimed to test a kisspeptin-based hormonal therapy on cultured Senegalese sole (G1) breeders, known to have reproductive dysfunctions. A single intramuscular injection of KISS2-10 decapeptide (250 µg/kg) was tested in females and males during the reproductive season, and gonad maturation, sperm motility, plasma levels of gonadotropins (Fsh and Lh) and sex steroids (11-ketotestosterone, testosterone and estradiol), as well as changes in small non-coding RNAs (sncRNAs) in plasma, were investigated. Fsh, Lh, and testosterone levels increased after kisspeptin injection in both sexes, while sperm analysis did not show differences between groups. Let7e, miR-199a-3p and miR-100-5p were differentially expressed in females, while miR-1-3p miRNA was up-regulated in kisspeptin-treated males. In silico prediction of mRNAs targeted by miRNAs revealed that kisspeptin treatment might affect paracellular transporters, regulate structural and functional polarity of cells, neural networks and intracellular trafficking in Senegalese sole females; also, DNA methylation and sphingolipid metabolism might be altered in kisspeptin-treated males. Results demonstrated that kisspeptin stimulated gonadotropin and testosterone secretion in both sexes and induced an unanticipated alteration of plasma miRNAs, opening new research venues to understand how this neuropeptide impacts in fish HPG axis. 相似文献
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903.
María José Moyano Fernando Ayala J. Federico Echávarri José Alba A. Ignacio Negueruela Francisco J. Heredia 《Journal of the American Oil Chemists' Society》2001,78(12):1221-1226
There are several simplified methods to measure the color of virgin olive oils. However, their reliability is questionable, as they provide errors that sometimes can be considerable. A new method to calculate color coordinates and objective chromatic parameters in the color region of these olive oils is proposed with the aim of overcoming these objections. The method is a simplification of the original method proposed by the Commission Internationale de l'Eclairage (CIE), based on the measurement of the complete visible spectrum, from 380 to 770 nm. The characteristic vector analysis provides new equations to calculate tristimulus values as functions of these transmittance values based on a reconstruction of oil transmission spectra measuring from three to six wavelengths. The results show that color differences exist between the color coordinates of the experimental samples and those obtained by means of the proposed method. For more than 90% of the samples, the difference was smaller than three CIELAB units when equations based on four or more wavelengths were used. 相似文献
904.
A generalized disjunctive programming formulation is presented for the optimal design of reactive distillation columns using tray-by-tray, phase equilibrium and kinetic based models. The proposed formulation uses disjunctions for conditional trays to apply the MESH and reaction kinetics equations for only the selected trays in order to reduce the size of the nonlinear programming subproblems. Solution of the model yields the optimal feed tray locations, number of trays, reaction zones, and operating and design parameters. The disjunctive program is solved using a logic-based outer-approximation algorithm where the MILP master problem is based on the big-M formulation of disjunctions, and where a special initialization scheme is used to reduce the number of initial NLP subproblems that need to be solved. Two examples are presented that include reactive distillation for the metathesis reaction of 2-pentene and for the production of ethylene glycol. The results show that the proposed method can effectively handle these difficult nonlinear optimization problems. 相似文献
905.
Ignacio N. Lobato 《时间序列分析杂志》1997,18(2):137-155
Several aspects of inference with long memory series in a multivariate framework are examined. The main result of this paper is to prove the consistency of the averaged cross- periodogram evaluated in a degenerating neighbourhood of zero frequency. We also illustrate several applications of that result and consider some specification issues. 相似文献
906.
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908.
Carlos J. Bernardos Maria Calderon Ignacio Soto Ana Beatriz Solana Kilian Weniger 《Computer Networks》2010,54(2):291-303
Wireless mesh networks are experiencing rapid progress and inspiring numerous applications in different scenarios, due to features such as autoconfiguration, self-healing, connectivity coverage extension and support for dynamic topologies. These particular characteristics make wireless mesh networks an appropriate architectural basis for the design of easy-to-deploy community or neighbourhood networks. One of the main challenges in building a community network using mesh networks is the minimisation of user intervention in the IP address configuration of the network nodes. In this paper we first consider the process of building an IP-based mesh network using typical residential routers, exploring the options for the configuration of their wireless interfaces. Then we focus on IP address autoconfiguration, identifying the specific requirements for community mesh networks and analysing the applicability of existing solutions. As a result of that analysis, we select PACMAN, an efficient distributed address autoconfiguration mechanism originally designed for ad-hoc networks, and we perform an experimental study – using off-the-shelf routers and assuming worst-case scenarios – analysing its behaviour as an IP address autoconfiguration mechanism for community wireless mesh networks. The results of the conducted assessment show that PACMAN meets all the identified requirements of the community scenario. 相似文献
909.
Rui L. Aguiar Hans Joachim Einsiedler José Ignacio Moreno 《Wireless Personal Communications》2009,49(3):335-351
The global communication infrastructure has taken an increased relevance for the future global multimedia village. This global
infrastructure has suffered from a mismatch between the conceptual models being used, and the effective operational networks
deployed to support it. This mismatch is now affecting the much needed developments to support a global village. This paper
presents a novel model for structuring communication networks which closely reflects the visions and needs from an operational
network. This model shows a path for protocol evolutions for the global communication infrastructure.
相似文献
José Ignacio MorenoEmail: |
910.
Noemí Merayo Tamara Jiménez Ramón J. Durán Patricia Fernández Ignacio de Miguel Rubén M. Lorenzo Evaristo J. Abril 《Photonic Network Communications》2010,19(3):257-264
A novel interleaved polling algorithm for Long-Reach EPONs is proposed in order to simultaneously provide subscriber and class
of service differentiation. It is demonstrated that the new polling algorithm applied to a typical 100 km Long-Reach EPON
performs better than centralized methods, where bandwidth prediction is needed to overcome the higher round trip time in which
ONUs cannot transmit. As polling methods in Long-Reach EPONs do not require prediction, they are much simpler and show less
computational complexity than centralized schemes, avoiding the inaccuracy of bandwidth prediction. Simulation results show
that the new algorithm increases the achieved throughput when compared to centralized algorithms with traffic prediction,
obtaining a significant reduction of both mean packet delay and packet loss ratio for the highest priority service level profiles. 相似文献