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241.
Luísa Genes Bruno Cid Fernando A. S. Fernandez Alexandra S. Pires 《Ecology and evolution》2017,7(6):1892-1897
As defaunation spreads through the world, there is an urgent need for restoring ecological interactions, thus assuring ecosystem processes. Here, we define the new concept of credit of ecological interactions, as the number of interactions that can be restored in a focal area by species colonization or reintroduction. We also define rewiring time, as the time span until all the links that build the credit of ecological interactions of a focal area have become functional again. We expect that the credit will be gradually cashed following refaunation in rates that are proportional to (1) the abundance of the reintroduced species (that is expected to increase in time since release), (2) the abundance of the local species that interact with them, and (3) the traits of reintroduced species. We illustrated this approach using a theoretical model and an empirical case study where the credit of ecological interactions was estimated. This new conceptual framework is useful for setting reintroduction priorities and for evaluating the success of conservation initiatives that aim to restore ecosystem services. 相似文献
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Jorge Parra-Nieto María Amor García del Cid Iñigo Aguirre de Cárcer Alejandro Baeza 《Biotechnology journal》2021,16(2):2000150
The use of nanoparticles in oncology to deliver chemotherapeutic agents has received considerable attention in the last decades due to their tendency to be passively accumulated in solid tumors. Besides this remarkable property, the surface of these nanocarriers can be decorated with targeting moieties capable to recognize malignant cells which lead to selective nanoparticle uptake mainly in the diseased cells, without affecting the healthy ones. Among the different nanocarriers which have been developed with this purpose, inorganic porous nanomaterials constitute some of the most interesting due to their unique properties such as excellent cargo capacity, high biocompatibility and chemical, thermal and mechanical robustness, among others. Additionally, these materials can be engineered to present an exquisite control in the drug release behavior placing stimuli-responsive pore-blockers or sensitive hybrid coats on their surface. Herein, the recent advances developed in the use of porous inorganic nanomedicines will be described in order to provide an overview of their huge potential in the look out of an efficient and safe therapy against this complex disease. Porous inorganic nanoparticles have been designed to be accumulated in tumoral tissues; once there to recognize the target cell and finally, to release their payload in a controlled manner. 相似文献
245.
Anguina pacificae n. sp. is described and illustrated from stem galls on bluegrass, Poa annua L., from golf courses along coastal California. The females are characterized by constrictions in the anterior and posterior connections of the isthmus with the respective parts of the esophagus, the long multicellular columella, and the sharply pointed tail tip. Males are dorsally curved after death; body width is increased markedly after 13 annuli in both sexes, and the tail is conical and with an acute terminus. 相似文献
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Concepción Lillo Almudena Velasco David Jimeno Elena Cid Juan M Lara José Aijón 《The journal of histochemistry and cytochemistry》2002,50(10):1289-1302
This study demonstrates the peculiarities of the glial organization of the optic nerve head (ONH) of a fish, the tench (Tinca tinca), by using immunohistochemistry and electron microscopy. We employed antibodies specific for the macroglial cells: glutamine synthetase (GS), glial fibrillary acidic protein (GFAP), and S100. We also used the N518 antibody to label the new ganglion cells' axons, which are continuously added to the fish retina, and the anti-proliferating cell nuclear antigen (PCNA) antibody to specifically locate dividing cells. We demonstrate a specific regional adaptation of the GS-S100-positive Müller cells' vitreal processes around the optic disc, strongly labeled with the anti-GFAP antibody. In direct contact with these Müller cells' vitreal processes, there are S100-positive astrocytes and S100-negative cells ultrastructurally identified as microglial cells. Moreover, a population of PCNA-positive cells, characterized as glioblasts, forms the limit between the retina and the optic nerve in a region homologous to the Kuhnt intermediary tissue of mammals. Finally, in the intraocular portion of the optic nerve there are differentiating oligodendrocytes arranged in rows. Both the glioblasts and the rows of developing cells could serve as a pool of glial elements for the continuous growth of the visual system. 相似文献
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Using a basic representation of dynamic systems, arterial blood pressure pulsation is converted into quasi-periodic orbits with the purpose of transforming a periodic phenomena into a cyclical one by plotting the pressure p(t) versus its first derivative dp/dt. This elementary mathematical procedure made it possible to evaluate the variability of the systemic arterial pressure pulsations, both systolic and diastolic, as well as the slope variability of the anachrotic and catachrotic phases. Two periods, which can be used to estimate different sources of variability, can be distinguished in the catachrotic phase. One corresponds to the open aortic valves, and the other is associated with the closed valves. Furthermore, through the first derivative of pressure oscillations we were able to identify small changes in arterial pressure, which appeared when the sampling rate was at least 150 samples per second. Since the time variable was converted into a parameter, the result was a synoptic or holistic approach, which is a considerable improvement for the visual analysis of cardiovascular phenomena. This simplified mathematical procedure can be easily implemented on a personal computer in real time and applied to all rhythmic phenomena in Physiology and Pathology. 相似文献
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Alberto Sanchez-Aguilera Diek W. Wheeler Teresa Jurado-Parras Manuel Valero Miriam S. Nokia Elena Cid Ivan Fernandez-Lamo Nate Sutton Daniel García-Rincn Liset M. de la Prida Giorgio A. Ascoli 《PLoS biology》2021,19(5)
Understanding brain operation demands linking basic behavioral traits to cell-type specific dynamics of different brain-wide subcircuits. This requires a system to classify the basic operational modes of neurons and circuits. Single-cell phenotyping of firing behavior during ongoing oscillations in vivo has provided a large body of evidence on entorhinal–hippocampal function, but data are dispersed and diverse. Here, we mined literature to search for information regarding the phase-timing dynamics of over 100 hippocampal/entorhinal neuron types defined in Hippocampome.org. We identified missing and unresolved pieces of knowledge (e.g., the preferred theta phase for a specific neuron type) and complemented the dataset with our own new data. By confronting the effect of brain state and recording methods, we highlight the equivalences and differences across conditions and offer a number of novel observations. We show how a heuristic approach based on oscillatory features of morphologically identified neurons can aid in classifying extracellular recordings of single cells and discuss future opportunities and challenges towards integrating single-cell phenotypes with circuit function.By integrating single-cell firing behavior during in vivo oscillations with morphological and molecular neuron classification in vitro, this study standardizes a framework for interpreting the functional roles of distinct circuit modules and ascribing extracellular recordings to identified neuron types. 相似文献