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Pathogenesis of glaucoma: how to prevent ganglion cell from axonal destruction?

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Neural Regeneration Research 2014年第23期9卷 2046-2047页

作者： francisco Javier Carreras Department of Surgery(Ophthalmology) Faculty of MedicineUniversity of Granada

Glaucoma is the main cause of irreversible blindness globally, but the pathogenesis of glaucoma is still pending consensus. In spite of great advances during the 20th and early 21st centuries in terms of detailed knowledge of pathological processes that take place in glaucoma, the exact pathogenesis is much less clear. Hypotheses abound, and the most researched areas are ischemia at the optic nerve head, blockade of ganglion cell axonal transport, peripapillary atrophy, and changes in the characteristics of the lamina cribrosa （Nucci et al., 2008）.

关键词： Pathogenesis of glaucoma RGCs cell

Possible implications of dysregulated nicotinic acetylcholine receptor diffusion and nanocluster formation in myasthenia gravis

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Neural Regeneration Research 2021年第2期16卷 242-246页

作者： francisco J.Barrantes Biomedical Research Institute(BIOMED)UCA-CONICET Buenos AiresArgentina

Myasthenia gravis is a rare and invalidating disease affecting the neuromuscular junction of voluntary *** classical form of this autoimmune disease is characterized by the presence of antibodies against the most abundant protein in the neuromuscular junction,the nicotinic acetylcholine *** variants of the disease involve autoimmune attack of non-receptor scaffolding proteins or enzymes essential for building or maintaining the integrity of this peripheral *** review summarizes the participation of the above proteins in building the neuromuscular junction and the destruction of this cholinergic synapse by autoimmune aggression in myasthenia *** review also covers the application of a powerful biophysical technique,superresolution optical microscopy,to image the nicotinic receptor in live cells and follow its motional *** hypothesis is entertained that anomalous nanocluster formation by antibody crosslinking may lead to accelerated endocytic internalization and elevated turnover of the receptor,as observed in myasthenia gravis.

关键词： agrin autoimmune diseases muscle end-plate muscle specific kinase MuSK myasthenia gravis nanoscopy neuromuscular junction nicotinic acetylcholine receptor rapsyn superresolution microscopy

Lessons from glaucoma: rethinking the fluid-brain barriers in common neurodegenerative disorders

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Neural Regeneration Research 2019年第6期14卷 962-966页

作者： francisco Javier Carreras Department of Surgery Faculty of MedicineUniversity of Granada

Glaucoma has been recently characterized as a member of the group of anoikis-related diseases. Anoikis, a form of apoptosis, can be triggered by the unfastening of adherent junctions present in astrocytes. In those areas of the central nervous system in which the soma of the neurons or their axons and dendrites are metabolically dependent on the activity of astrocytes, a derangement of the lactate shuttle caused by a separation between the plasma membranes of neurons and astrocytes would result in metabolic impairment of the neurons themselves. In glaucoma, the triggering event has been attributed to the posterior deviation of aqueous humor towards the astrocyte-rich prelaminar tissue of the optic nerve head. The mean calcium content in the aqueous is able to interfere with calcium-dependent adherent junctions and induce anoikis of the astrocytes. As the cerebrospinal fluid has a similar base calcium concentration, a shunt of cerebrospinal fluid through the cerebral parenchyma would be able to interfere in the astrocytic architecture with dire consequences to the metabolically dependent neurons. Here the similitude between glaucoma,amyotrophic lateral sclerosis and Alzheimer's disease are discussed and the concept of the break in the fluid-brain barrier, as an event separated from the blood-brain barrier, is stressed.

关键词： fluid-brain barriers blood-brain barrier cerebrospinal fluid aqueous humor calcium ion glaucoma amyotrophic lateral sclerosis Alzheimer’s disease

Polygeneration Study of Low-to-Medium Enthalpy Geothermal Reservoirs in Mexico

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Journal of Thermal Science 2021年第3期30卷 1077-1087页

作者： CHÁVEZ Oscar GODÍNEZ francisco Tecnológico Nacional de México/I.T.Chihuahua.Av.Tecnológico 2909 C.P.31310ChihuahuaChihuahuaMéxico Instituto de Ingeniería Universidad Nacional Autónoma de MéxicoUNAMC.U.Ciudad de MéxicoC.P.04510México Polo Universitario de Tecnología Avanzada Universidad Nacional Autónoma de MéxicoVía de la Innovación No.410Autopista Monterrey-Aeropuertokm.10 PIITC.P.66629Apodaca Nuevo LeónMéxico

This study combines the thermodynamic analysis of a polygeneration system along with the numerical modelling of the thermal behavior of geothermal reservoirs in Mexico to exploit their *** reservoir was modeled as a porous medium assuming a five-spot well configuration and local thermal *** heat conduction-convection along with the Laplace equations were solved to compute temperature distributions,the useful life and the optimum distance between injection-extraction *** predicted temperature and pressure of the geothermal fluid at the outlet of the reservoir were exploited in the polygeneration system consisting of:(1)a Rankine cycle,(2)an absorption refrigeration cycle,and(3)a heat *** developed approach allows calculating both the optimal distance between injection-extraction wells and the global(utilization)efficiency of six arrangements(each composed by a reservoir connected to a polygeneration system)by assuming that reservoirs have a lifespan of 30 *** also show that:(a)due to the low efficiency of the Rankine cycle,very little thermal energy is converted into electrical one;(b)not only the temperature and the size are important when evaluating the power production performance of reservoirs,but also the permeability plays a fundamental role;(c)the first law efficiency of the polygeneration system ranges from 41.9%to 43.7%;(d)the utilization efficiency of the six arrangements lies in the range between 25.8%and 31%.

关键词： polygeneration system geothermal reservoir local thermal equilibrium low-to-medium enthalpy

Impact of emulated inertia from wind power on under-frequency protection schemes of future power systems

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Journal of Modern Power Systems and Clean Energy 2016年第2期4卷 211-218页

作者： francisco Manuel GONZALEZ-LONGATT Loughborough University Loughborough LE652JGUK

Future power systems face several *** of them is the use of high power converters that decouple new energy sources from the AC power *** situation decreases the total system inertia affecting its ability to overcome system frequency *** wind power industry has created several controllers to enable inertial response on wind turbines generators:artificial,emulated,simulated,or synthetic *** paper deals with the issues related to the emulated inertia of wind turbines based on full-converters and their effect on the under-frequency protection schemes during the recovery period after system frequency disturbances *** main contribution of this paper is to demonstrate the recovery period of under-frequency transients in future power systems which integrate wind turbines with emulated inertia capability does not completely avoid the worse scenarios in terms of under-frequency load *** extra power delivered from a wind turbine during frequency disturbances can substantially reduce the rate of frequency *** it provides time for the active governors to respond.

关键词： Frequency controller Frequency stability Power system Protection scheme Wind turbine generator

Integrating time progression in ecoimmunology studies: beyond immune response intensity

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Current Zoology 2019年第2期65卷 205-212页

作者： francisco Javier ZAMORA-CAMACHO Department of Biological Sciences Dartmouth College Hanover New Hampshire USA Department of Biogeography and Global Change Museo Nacional de Ciencias Naturales (MNCN) Spanish National Research Council (CSIC) Madrid Spain

Habitat alterations in agroecosystems may damage amphibian immune capacity. As agroecosystem extension is increasing worldwide, broader-context knowledge on the effects of agroecosystem stressful conditions on amphibian immune capacity is crucial for understanding and management of amphibian global declines. However, most studies on ecoimmunology assume synchronal amonggroup immune-response peaks, and focus on immune response after standardized time lapses, neglecting its progress!on. Herein, I compared inflamatory response short-term progression of agro ecosystem and n atural-habitat female and male n atterjack toads Epi da lea calamita, by measuri ng swelling response, once per hour, 6 h following an artificial immune challenge with innocuous antigen phytohemagglutinin. I also compared maximum magnitude of swelling response, irrespective of the moment when it was reached. Habitat differences arose only 3 h after challenge, when naturalhabitat toads showed greater swelling response. Maximum magnitude of swelling response was similar in toads from both habitats. However, agroecosystem toads showed a delayed swelling response as compared with natural-habitat conspecifics, probably as a consequenee of agroecosystem stressful conditions. Such a delay suggests a weaker immune capacity, and consequently impaired anti-pathogen performance. Regarding sex, swelling response magnitude did not differ between males and females. Female swelling response peaked earlier, but that of males was more sustai ned in time, which con tradicts general across-taxa fin dings that males show impaired immune response. Interestingly, results suggest that measuring swelling response only after some standardized period following stimulation may be a simplistic approach and produce unrealistic results. Consequently, studies on ecoimmunology should implement swelling response progression in order to produce unbiased science.

关键词： agroecosystem amphibian immunocompetence natural habitat immune response progressi on

Comparison of *** oxygen plasma and chemical treatments for surface modifications of Ti6Al4V

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Bio-Design and Manufacturing 2019年第2期2卷 65-75页

作者： María Elena Alemán.Domínguez Zaida Ortega Antonio N.Benítez Aday romero.Pérez Ling Wang Ruymán Santana.Farré francisco Rodríguez.Esparragón Departamento de Ingeniería de Procesos Universidad de Las Palmas de Gran CanariaCampus universitario de Tafira Baja35017 Las Palmas de Gran CanariaSpain Departamento de Ingeniería Mecánica Universidad de Las Palmas de Gran CanariaCampus universitario de Tafira Baja35017 Las Palmas de Gran CanariaSpain State Key Laboratory for Manufacturing System Engineering School of Mechanical EngineeringXi’an Jiaotong UniversityScience and Technology Park of Xi’an Jiaotong UniversityYanta DistrictXi’an City 710054Shaanxi ProvincePeople’s Republic of China Research Unit Dr.Negrín University Hospital35019 Las PalmasCanary IslandsSpain

Different treatments were conducted over Ti6Al4V samples in order to produce a surface modification to increase cell attachment and *** surface treatments evaluated in this study were as follows:etching with sulfuric acid/hydrochloric acid,oxidizing with hydrogen peroxide and low-pressure oxygen plasma *** contrast to other works found in the literature,this research conducts a comparison between different chemical and physical treatments in terms of different assays for surface characterization:X-ray diffraction,scanning electron microscope(SEM),energy-dispersive X-ray spectroscopy,water contact angle,release of vanadium ions and cell viability tests(MTT)of human osteoblasts(hFOB 1.19).Cell morphology over the different substrates was also studied by SEM *** was found that plasma and peroxide treatments increase the O/Ti ratio at the titanium surface and provide an increase in cell *** the other hand,acid etching provides a superhydrophilic surface which is not able to improve the cell attachment of human osteoblasts.

关键词： Surface activation Titanium alloys Surface functionalization Low-pressure plasma

Entropy model to assess sediment resuspension probability and trap efficiency of small dams

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International Journal of Sediment Research 2022年第5期37卷 675-686页

作者： francisco Jairo Soares Pereira Antonio Viana da Silva Filho José Wellington Batista Lopes José Carlos de Araújo Department of Agricultural Engineering Federal University of Ceará Campus Do Pici Rural Federal University of Pernambuco Federal University of Piauí

In the Brazilian drylands, there are tens of thousands of small dams. Despite their paramount importance to the rural population, they are rarely monitored. Water demand increases with time while, simultaneously, siltation reduces reservoir water capacity and availability. Reservoir siltation models are, therefore, mandatory to manage the numerous ungauged small dams in these *** objective of the current study is to improve sediment trap efficiency(TE) modeling by including resuspension as a key probabilistic process. The Shannon entropy was used to estimate the sediment resuspension probability, which was merged with the Camp model and generated the RETSED entropy model. To validate the RETSED model, an experimental check dam(ECD, 300 m3), located in the Gilbu es desertification site, Brazil, was monitored hourly during one hydrological year(July 2018-July 2019). Measurements show that the annual volumetric decline of the check dam was 12%; and that the average trap efficiency equaled 86%. Only 9.5% of the hourly sediment concentration outflow exceeded the average plus one standard deviation, showing that the reservoir is well mixed; a fact which highlights the relevance of the resuspension process. Three empirical models failed to mimic the experimental results: Churchill(TE = 99%), Brune(TE = 75%), and Maryland(TE = 94%). According to the RETSED entropy model, the resuspension probability during the experiment was 10%and TE = 81%, a value only 6% below the measured one. The Camp model simulated TE = 89%, only 3%higher than the measured value, but confirmed the Camp model’s tendency to overestimate TE due to a disregard of resuspension. The deterministic model showed low sensitivity concerning the hydrodynamic effects, whereas the entropy formulation proved to be more consistent with physical behavior: the resuspension probability clearly increased and trap efficiency decreased with rising reservoir discharge.

关键词： Erosion Check dam Sedimentation Ungauged basins Camp model

Changes in the sorption, desorption, distribution, and availability of copper, induced by application of sewage sludge on Chilean soils contaminated by mine tailings

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Journal of Environmental Sciences 2012年第5期24卷 912-918页

作者： Tatiana Garrido Jorge Mendoza francisco Arriagada Faculty of Chemical Sciences and Pharmacy Department of Inorganic and Analytical Chemistry University of Chile

The effect of mine tailings and sewage sludge was evaluated on sorption, desorption, availability and distribution of copper in two soils, one high （sandy soil） and one low in copper （clay soil）. In both soils contaminated by mine tailings the copper sorption capacity and the affinity of the substrate for the metal decreased substantially compared to the uncontaminated soils, however, the sorption remained always high in the clay soil substrates. In the substrates with sandy soil, the high Cu content and lower clay content were determining factors in the lower magnitude of the sorption. Similarly, metal desorption was closely related to these two parameters, and it was higher in clay soil with lower pH. In general, the application of sewage sludge favored the sorption of Cu in soils contaminated and uncontaminated with mine tailings, and in all cases desorption decreased, an effect that remained for at least 30 days. Simple extraction of Cu with CaCl2 and diethylenetriaminepentaacetic acid gave contradictory results, so a careful choice of the procedure is required, depending on the level of metal in the soil and on the acting principle of the extracting agent. In that relation, more complete information on the changes in the metal forms was obtained by application of the sequential extraction procedure proposed by the European Community Bureau of Reference.

关键词： sewage sludge copper sorption mine tailings copper desorption European Community Bureau of Reference sequential extraction