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Intravitreal dexamethasone implants for diabetic macular edema

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International Journal of Ophthalmology(English edition) 2018年第1期11卷 77-82页

作者： Alicia Pareja-Ríos Paloma ruiz-de la Fuente-Rodríguez sergio Bonaque-González Maribel López-Gálvez Virginia Lozano-López Pedro Romero-Aroca University Hospital of the Canary Islands Santa Cruz deTenerifeIslas Canarias 38320Spain Wooptix S.L San Cristobal de La Laguna 38204Spain University Clinical Hospital of Valladolid Institute of Applied Ophthalmobiology(IOBA)Valladolid 47011Spain University Hospital Sant Joan de Reus Tarragona 43204Spain

AIM： To evaluate the safety and efficacy of a dexamethasone（DEX） intravitreal implant for diabetic macular edema（DME）.METHODS： Totally 113 eyes of 84 patients were divided in three subgroups： naive patients（n=11）, pseudophakic patients（n=72） and phakic patients（n=30）. Inclusive criterion comprised adult diabetic patients with central fovea thickening and impaired visual acuity resulting from DME for whom previous standard treatments showed no improvement in both central macular thickness（CMT） and best corrected visual acuity（BCVA） after at least 3 mo of treatment. Outcome data were obtained from patient visits at baseline and at months 1, 3, 5, 9 and 12 after the first DEX implant injection. At each of these visits, patients underwent measurement of BCVA, a complete eye examination and measurement of CMT and macular volume（MV） carried out with optical coherence tomography（OCT） images. RESULTS： Seventy-three eyes（64.5%） received a single implant, 30（26.5%） received two implants and 10（9%） received three implants. At baseline, average in BCVA, CMT and MV were 43.5±20.8, 462.8±145 and 12.6±2.5 respectively. These values improved significantly at 1 mo（BCVA： 47.2±19.5, CMT： 339.6±120, MV： 11.11±1.4） and 3 mo（BCVA： 53.2±18.1, CMT： 353.8±141, MV： 11.3±1.3）（P≤0.05）. At 5 mo（BCVA： 50.9±19.8, CMT： 425±150, MV： 12.27±2.3）, 9 mo（BCVA： 48.4±17.6, CMT： 445.5±170, MV： 12.5±2.3） and 12 mo（BCVA： 47.7±18.8, CMT： 413.2±149, MV： 12.03±2.5）, improvements in the three parameters were no longer statistically significant and decreased progressively but did not reach baseline values. There were no clinical differences between subgroups. Ocular complications were ***： Patients with DEX implants show maximum efficacy at 3 mo which then declined progressively, but is still better than baseline values at the end of follow-up.

关键词： Ozurdex diabetic macular edema dexamethasone retina diabetes

Separation and recovery of critical metal ions using ionic liquids

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Advances in Manufacturing 2016年第1期4卷 33-46页

作者： Terence Makanyire sergio Sanchez-Segado Animesh Jha Institute for Materials Research University of LeedsLeeds LS2 9JT UK

Separation and purification of critical metal ions such as rare-earth elements （REEs）, scandium and niobium from their minerals is difficult and often deter- mines if extraction is economically and environmentally feasible. Solvent extraction is a commonly used metal-ion separation process, usually favored because of its sim- plicity, speed and wide scope, which is why it is often employed for separating trace metals from their minerals. However, the types of solvents widely used for the recovery of metal ions have adverse environmental impact. Alternatives to solvent extraction have been explored and advances in separation technologies have shown commer- cial establishment of liquid membranes as an alternative to conventional solvent extraction for the recovery of metals and other valuable materials. Liquid membrane transport incorporates solvent extraction and membrane separation in one continuously operating system. Both methods con- ventionally use solvents that are harmful to the environ- ment, however, the introduction of ionic liquids （ILs） over the last decade is set to minimize the environmental impact of both solvent extraction and liquid membrane separation processes. ILs are a family of organic molten salts with low or negligible vapour pressure which may be formed below 100 ~C. Such liquids are also highly thermally stable and less toxic. Their ionic structure makes them thermody- namically favorable solvents for the extraction of metallic ions. The main aim of this article is to review the current achievements in the separation of REE, scandium, niobium and vanadium from their minerals, using ILs in eithersolvent extraction or liquid membrane processes. The mechanism of separation using ILs is discussed and the engineering constraints to their application are identified.

关键词： Critical metals Ionic liquids (ILs) -Niobium Tantalum Rare-earth elements (REEs)Vanadium Scandium

Invasive strategy in elderly patients with acute coronary syndrome in 2018: close to the truth?

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Journal of Geriatric Cardiology 2019年第2期16卷 114-120页

作者： sergio García-Blas Clara Bonanad Juan Sanchis Servei de Cardiologia Hospital Clínic Universitari de València INCLIVA Universitat de ValènciaCIBERCV

Elderly population constitutes an increasingly larger proportion of patients admitted for acute coronary syndromes(ACS).The optimal management of ACS in these patients is still a challenge due to their clinical peculiarities and the paucity of specific data,and they have been traditionally managed more conservatively mainly based on subjective *** ST^segment elevation acute myocardial infarction urgent reperfusion is the standard of care and there is no upper age *** non-ST segment elevation acute myocardial infarction evidence is controversial,incomplete and mainly focused on chronological *** a strict conservative strategy should be avoided,routine invasive strategy may reduce the occurrence of myocardial infarction and need for revascularization at follow-up with no established benefit in terms of *** characteristics associated with aging,such as comorbidities and frailty,further discriminate patient's risk beyond *** is scarce,but it suggests that these features may modulate the benefit of invasive strategy in this *** trials should clarify the optimal management of ACS based on these parameters.

关键词： Acute coronary syndromes Comorbidity Frailty Percutaneous coronary intervention The elderly

Phenotypic heterogeneity in amyotrophic lateral sclerosis type 8 and modifying mechanisms of neurodegeneration

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Neural Regeneration Research 2021年第9期16卷 1776-1778页

作者： Danyllo Oliveira sergio Verjovski-Almeida Mayana Zatz Human Genome and Stem Cell Research Center Department of Genetics and Evolutionary BiologyInstitute of BiosciencesUniversity of São PauloSão PauloSPBrazil Laboratório de Expressão Gênica em Eucariotos Instituto Butantan Departmento de Bioquímica Instituto de QuímicaUniversidade de São PauloSão PauloSPBrazil

In his accounts "On longevity and shortness of life", Aristotle considered how diseased states could be interchangeably associated with long and short lifespans. He believed that the presence of opposite elements and ... 详细信息

关键词： opposite elements states

Comparison of Cellular Automaton and Phase Field Models to Simulate Dendrite Growth in Hexagonal Crystals

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Journal of Materials Science & Technology 2012年第2期28卷 137-146页

作者： Mohsen Asle Zaeem Hebi Yin sergio D. Felicelli Center for Advanced Vehicular Systems Mississippi State University Starkville MS 39759 USA Mechanical Engineering Department Mississippi State University Starkville MS 39759 USA Materials Processing Group Oak Ridge National Laboratory Oak Ridge TN 37831 USA

A cellular automaton （CA）-finite element （FE） model and a phase field （PF）-FE model were used to simulate equiaxed dendritic growth during the solidification of hexagonal metals. In the CA-FE model, the conservation equations of mass and energy were solved in order to calculate the temperature field, solute concentration, and the dendritic growth morphology. CA-FE simulation results showed reasonable agreement with the previously reported experimental data on secondary dendrite arm spacing （SDAS） vs cooling rate. In the PF model, a PF variable was used to distinguish solid and liquid phases similar to the conventional PF models for solidification of pure materials. Another PF variable was considered to determine the evolution of solute concentration. Validation of both models was performed by comparing the simulation results with the analytical model developed by Lipton-Glicksman-Kurz （LGK）, showing quantitatively good agreement in the tip growth velocity at a given melt undercooling. Application to magnesium alloy AZ91 （approximated with the binary Mg-8.9 wt% AI） illustrates the difficulty of modeling dendrite growth in hexagonal systems using CA-FE regarding mesh-induced anisotropy and a better performance of PF-FE in modeling multiple arbitrarily-oriented dendrites growth.

关键词： Dendrite growth Cellular automaton Phase-field model Finite element~ Magnesium alloy

Neural functions of small heat shock proteins

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Neural Regeneration Research 2022年第3期17卷 512-515页

作者： Teresa de los Reyes sergio Casas-Tintó Instituto Cajal CSICMadridSpain

Stress response is a cellular widespread mechanism encoded by a common protein program composed by multiple cellular factors that converge in a defense reaction to protect the cell against *** many mechanisms described,heat shock proteins were proposed as universally conserved protective factors in the stress core proteome,coping with different stress stimuli through its canonical role in protein ***,emerging evidences reveal non-canonical roles of heat shock proteins relevant for physiological and pathological ***,we review the implications of inducible heat shock proteins in the central nervous system *** particular,we discuss the relevance of heat shock proteins in the maintenance of synapses,as a balanced protective mechanism in central nervous system development,pathological conditions and aging.

关键词： aging central nervous system chaperones environment neuroprotection pathology stress synapses

Air temperature feedback and its contribution to global warming

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Science China Earth Sciences 2018年第10期61卷 1491-1509页

作者： Xiaoming HU Ming CAI Song YANG sergio A.SEJAS School of Atmospheric Sciences Sun Yat-sen University Guangzhou 510275 China Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies Guangzhou 510275 China Department of Earth Ocean and Atmospheric Sciences Florida State University Tallahassee 32306 USA Institute of Earth Climate and Environment System Sun Yat-sen University Guangzhou 510275 China NASA Langley Research Center Climate Science Branch Hampton 03842 USA

Air temperature feedback results from the thermal-radiative coupling between the atmosphere and the surface and plays an important role in surface energy balance. This paper reveals the contribution of air temperature feedback to the global warming from 1980 to 2000. The air temperature feedback kernel, evaluated using the ERA-Interim reanalysis data, is used to discuss the physical mechanism for air temperature feedback, the dependency of the strength of air temperature feedback on the climatological spatial distributions of air temperature, water vapor and cloud content, and the contributions of air temperature feedback to rapid global warming. The coupling between temperature feedback and each of the external forcings and individual feedback processes will amplify the anomaly of direct energy flux convergence at the surface induced by the external forcings and individual processes. The air temperature feedback amplifies the initial surface warming due to the increase in CO2 concentration, ice and snow melting, increase in water vapor, and change in ocean heat storage. It also amplifies the surface warming due to the longwave radiaitve forcing associated with the increase in cloud cover, which acts to suppress the cooling of the shortwave effect of cloud forcing. Overall, temperature feedback plays an important role in the global warming from 1980 to2000, as the net positive contribution to the perturbation of global mean energy flux at the surface from the air temperature feedback is larger than the net negative contribution from external forcing and all non-temperature feedbacks.

关键词： Global warming Air temperature feedback Surface energy budget

Corrosion Behavior of Ψ and β Quasicrystalline Al–Cu–Fe Alloy

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Acta Metallurgica Sinica(English Letters) 2015年第9期28卷 1117-1122页

作者： Alvaro Torres sergio Serna Cristobal Patio Gerardo Rosas Facultad de Ciencias Químicas e Ingeniería P.A. Ing.Mecnica UAEM Av. Universidad 1001 Col. Chamilpa62210 Cuernavaca Mor. Mexico Centro de Investigación en Ingeniería y Ciencias Aplicadas UAEM Av. Universidad 1001 Col. Chamilpa62210 Cuernavaca Mor. Mexico Facultad de Ingeniería Universidad Autónoma del CarmenCampus Ⅲ Avenida Central S/N Esq. con Fracc. MundoMaya C.P. 24115 Ciudad del Carmen Campeche Mexico Instituto de Investigaciones Metalurgicas UMSNH Edificio U. Ciudad Universitaria Morelia Mich. 58000 Mexico

Two nanostructured A1-Cu-Fe alloys, A164Cu24Fe12 and A162.5Cu25.2Fe12.3, have been studied. Icosahedral quasicrystalline （ψ） A164CH24FeI2 and crystalline cubic （ β） ***25.2Fe12.3 cylindrical ingots were first produced using normal casting techniques. High-energy mechanical milling was then conducted to obtain β icosahedral and β intermetallic nanostructured powders. Electrochemical impedance spectroscopy, linear polarization resistance, and potentiodynamic polarization were used to investigate the electrochemical corrosion characteristics of the powders in solutions with different pH values. Current density （icorr）, polarization resistance （Rp）, and impedance modulus （121） were determined. The results showed that regardless of pH value, increasing the solution temperature enhanced the corrosion resistance of the both phases. However, the electrochemical behavior of the phase indicated that its stability depends on the submerged exposure time in neutral and alkaline environments. This behavior was related to the type of corrosion products present on the surfaces of the particles along with the diffusion and charge-transfer mechanisms of the corrosion process.

关键词： Nano-quasicrystalline AI-Cu-Fe alloy Mechanical alloying Corrosion

Sliding Mode Control in Power Converters and Drives: A Review

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IEEE/CAA Journal of Automatica Sinica 2022年第3期9卷 392-406页

作者： Ligang Wu Jianxing Liu sergio Vazquez Sudip K.Mazumder IEEE Department of Control Science and Engineering Harbin Institute of TechnologyHarbin 150001China Electronic Engineering Department Universidad de Sevilla41092 SevillaSpain Electrical and Computer Engineering Department University of Illinois ChicagoChicagoIL 60607 USA

Sliding mode control(SMC)has been studied since the 1950s and widely used in practical applications due to its insensitivity to matched *** aim of this paper is to present a review of SMC describing the key developments and examining the new trends and challenges for its application to power electronic *** fundamental theory of SMC is briefly reviewed and the key technical problems associated with the implementation of SMC to power converters and drives,such chattering phenomenon and variable switching frequency,are discussed and *** recent developments in SMC systems,future challenges and perspectives of SMC for power converters are discussed.

关键词： Motor drive power electronics systems sliding mode control