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我怎样使公司扭亏为盈——与邓白氏公司董事会主席Allan ***的访谈

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商学院 2006年第3期 66-68页

作者： Brian Hanessian carlos sierra 麦肯锡芝加哥分公司

O＆B（邓白氏公司）的CEO兼董事会主席Allen Loren解释了他在过去的四年中如何实现每年两位数的收益增长，并将公司的市值提高了3倍以上。

关键词：董事会主席 CEO 收益率邓白氏公司市场价值 Allan Z.Loren

An unsupervised pattern recognition methodology based on factor analysis and a genetic-DBSCAN algorithm to infer operational conditions from strain measurements in structural applications

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Chinese Journal of Aeronautics 2021年第2期34卷 165-181页

作者： Juan carlos PERAFAN-LOPEZ Julian sierra-PEREZ Grupo de Investigacion en Ingenieria Aeroespacial Universidad Pontificia BolivarianaCircular 170-01Medellin 050031Colombia

Structural Health Monitoring(SHM) suggests the use of machine learning algorithms with the aim of understanding specific behaviors in a structural system. This work introduces a pattern recognition methodology for operational condition clustering in a structure sample using the well known Density Based Spatial Clustering of Applications with Noise(DBSCAN) *** methodology was validated using a data set from an experiment with 32 Fiber Bragg Gratings bonded to an aluminum beam placed in cantilever and submitted to cyclic bending loads under 13 different operational conditions(pitch angles). Further, the computational cost and precision of the machine learning pipeline called FA + GA-DBSCAN(which employs a combination of machine learning techniques including factor analysis for dimensionality reduction and a genetic algorithm for the automatic selection of initial parameters of DBSCAN) was measured. The obtained results have shown a good performance, detecting 12 of 13 operational conditions, with an overall precision over 90%.

关键词： Clustering DBSCAN Factor analysis FBGs Pattern recognition Strain field

Differential response of injured and healthy retinas to syngeneic and allogeneic transplantation of a clonal cell line of immortalized olfactory ensheathing glia:a double-edged sword

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Neural Regeneration Research 2025年第8期20卷 2395-2407页

作者： María Norte-Muñoz María Portela-Lomba Paloma Sobrado-Calvo Diana Simón Johnny Di Pierdomenico Alejandro Gallego-Ortega Mar Pérez JoséMCabrera-Maqueda Javier sierra Manuel Vidal-Sanz María Teresa Moreno-Flores Marta Agudo-Barriuso Grupo de Investigación Oftalmología Experimental Departamento de OftalmologíaOptometríaOtorrinolaringología y Anatomía PatológicaFacultad de MedicinaUniversidad de MurciaInstituto Murciano de Investigación Biosanitaria(IMIB)Campus de Ciencias de la SaludMurciaSpain Experimental Sciences Faculty Universidad Francisco de VitoriaPozuelo de AlarcónMadridSpain Anatomy Histology and Neuroscience DepartmentMedicine FacultyUniversidad Autónoma de MadridMadridSpain Center of Neuroimmunology Service of NeurologyLaboratory of Advanced Imaging in Neuroimmunological DiseasesHospital Clínic of BarcelonaInstitut d’Investigacions Biomèdiques August Pi i Sunyer(IDIBAPS)and Universitat de BarcelonaBarcelonaSpain Medicine Faculty Universidad Francisco de VitoriaPozuelo de AlarcónMadridSpain

Olfactory ensheathing glia promote axonal regeneration in the mammalian central nervous system,including retinal ganglion cell axonal growth through the injured optic ***,it is unknown whether olfactory ensheathing glia also have neuroprotective *** ensheathing glia express brain-derived neurotrophic factor,one of the best neuroprotectants for axotomized retinal ganglion ***,we aimed to investigate the neuroprotective capacity of olfactory ensheating glia after optic nerve *** ensheathing glia cells from an established rat immortalized clonal cell line,TEG3,were intravitreally injected in intact and axotomized retinas in syngeneic and allogeneic mode with or without microglial inhibition or immunosuppressive *** and gene expression analyses were *** bulb-derived primary olfactory ensheathing glia and TEG3 express major histocompatibility complex classⅡ*** and syngenically transplanted TEG3 cells survived in the vitreous for up to 21 days,forming an *** axotomized retinas,only the allogeneic TEG3 transplant rescued retinal ganglion cells at 7 days but not at 21 *** these retinas,microglial anatomical activation was higher than after optic nerve crush *** intact retinas,both transplants activated microglial cells and caused retinal ganglion cell death at 21 days,a loss that was higher after allotransplantation,triggered by pyroptosis and partially rescued by microglial inhibition or ***,neuroprotection of axotomized retinal ganglion cells did not improve with these *** different neuroprotective properties,different toxic effects,and different responses to microglial inhibitory treatments of olfactory ensheathing glia in the retina depending on the type of transplant highlight the importance of thorough preclinical studies to explore these variables.

关键词： cell therapy immune recognition major histocompatibility complex class II(MHCII) neuroprotection olfactory ensheathing glia retinal ganglion cells

Gut passage of epigeous ectomycorrhizal fungi by two opportunistic mycophagous rodents

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Current Zoology 2011年第3期57卷 293-299页

作者： Citlalli CASTILLO-GUEVARAl Josette sierra Gema GALINDO-FLORES Mariana CUAUTLE carlos LARA Centro de Investigacion en Ciencias Biologicas Universidad Autonoma de Tlaxcala Km 10.5 Autopista Tlaxcala-San Martin Texmelucan San Felipe Ixtacuixtla Tlaxcala 90120 Mexico Departamento de Quimica y Biologfa Universidad de las Americas-Puebla Ex-hacienda Sta Catarina Martir s/n Cholula Puebla 72810 Mexico Centro Tlaxcala de Biologia de la Conducta Universidad Autdnoma de Tlaxcala-UNAM Carretera Tlaxcala-Puebla Km 1.5 s/n Tlaxcala Tlaxcala 90070 Mexico

Mycophagists can influence fungal diversity within their home ranges by ensuring the continued and effective dispersal of spores from one site to another. However, the passage of spores through the digestive tract of vertebrates can affect the activity and viability of the spores ingested. This phenomenon has been rarely documented in opportunistic mycophagists consuming epigeous fungi. Using laboratory experiments, we investigated the activity and viability of spores of two epigeous ectomycorrhizal fungal species （Laccaria trichodermophora and SuiUus tomentosus） after passage through the digestive tract of two opportunistic mycophagous small rodents, the volcano mouse Peromyscus alstoni and the deer mouse P maniculatus. We found that passage through the gut of either species of rodent had a significant effect on spore activity and viability for both fungal species. The proportion of active spores （0.37-0.40） of L. trichodermophora in the feces of both species of rodents was less than that recorded for the control （0.82）. However, the proportion of active spores （0.644）.73） of S. tomentosus in the feces of each species of rodent was higher than in the control （0.40）. On the other hand, the viability of spores was lower （0.26-0.30 in L. trichodermophora and 0.604）.69 in S. tomentosus） for both fungi when consumed by either rodent relative to the controls （0.90 in L. trichodermophora and 0.82 in S. tomentosus）. These findings suggest that these rodent species may be effective dispersers of both epigeous fungi [Current Zoology 57 （3）： 293-299, 2011].

关键词： Gut passage Epigeous ectomycorrhizal fungi Mexico Spore activity and viability Peromyscus

Site Characterization Index for Continuous Power Quality Monitoring Based on Higher-order Statistics

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Journal of Modern Power Systems and Clean Energy 2022年第1期10卷 222-231页

作者： Olivia Florencias-Oliveros Juan-José González-de-la-Rosa Jose-María sierra-Fernández Agustín Agüera-Pérez Manuel-Jesús Espinosa-Gavira José-carlos Palomares-Salas Department of Automation Engineering ElectronicsArchitecture and Computers NetworksResearch Group TIC168Higher Polytechnic SchoolUniversity of CádizAlgeciras 11202Spain

The high penetration of distributed generation(DG)has set up a challenge for energy management and consequently for the monitoring and assessment of power quality(PQ).Besides,there are new types of disturbances owing to the uncontrolled connections of non-linear *** stochastic behaviour triggers the need for new holistic indicators which also deal with big data of PQ in terms of compression and scalability so as to extract the useful information regarding different network states and the prevailing PQ disturbances for future risk assessment and energy management *** and continuous monitoring would guarantee the report to claim for damages and to assess the risk of PQ *** this context,we propose a measurement method that postulates the use of two-dimensional(2D)diagrams based on higher-order statistics(HOSs)and a previous voltage quality index that assesses the voltage supply waveform in a continous monitoring *** suitable for both PQ and reliability applications,the results conclude that the inclusion of HOS measurements in the industrial metrological reports helps characterize the deviations of the voltage supply waveform,extracting the individual customers’pattern fingerprint,and compressing the data from both time and spatial *** method allows a continuous and robust performance needed in the SG ***,the method can be used by an average consumer as a probabilistic method to assess the risk of PQ deviations in site characterization.

关键词： Continuous statistical monitoring big data data compression higher-order statistics(HOSs) power quality(PQ)

Biodiesel Production from Waste Cooking Oil by Enzymatic Catalysis Process

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Journal of Chemistry and Chemical Engineering 2013年第10期7卷 993-1000页

作者： Ignacio Contreras Andrade Fabio Emiro sierra Vargas carlos Alberto Guerrero Fajardo Department of Biology and Chemistry University of Sinaloa Culiacan 80007 Mexico Department of Chemistry National University of Colombia Bogota 11001 Colombia

Biodiesel is an excellent option for reducing dependence on fossil fuels with environmental advantages by reducing hazardous emissions. The enzymatic transesterification has attracted the attention of researchers in the last decade and the advantages of enzymatic catalysis show that the production of biodiesel by this route has good potential, mainly because it is friendly environment. For biodiesel, production process by enzyme catalysis is chosen the response surface methodology. It is an experimental strategy to find the best operating conditions oftransesterification reaction to improve the biodiesel quality. The Process has three variables： temperature, molar ratio oil-alcohol and catalyst quantity. The process was monitored by GC-FID （gas chromatography with flame ionization detector）. The yield of the transesterification reaction by enzymatic catalysis decreases with increasing temperature, and may be due to inactivation of the enzyme by denaturation at temperatures above 50 ℃. The second-order design used was the ＂CDC （central design composition）＂ which produced a maximum yield of 95.5% in the transesterification reaction by enzymatic catalysis obtained at a temperature of 45 ℃, molar ratio methanol：oil of 8：1 and a catalyst loading of 8% wt.

关键词： Biodiesel waste cooking oil transesterification reaction enzymatic catalysis biofuel

Changes in Mangrove Epifaunal Assemblages Caused by Forest Logging during Hunting of the Neotropical Cormorant (<i>Phalacrocorax brasilianus</i>) on the Colombian Pacific Coast

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Open Journal of Marine Science 2012年第4期2卷 150-156页

作者： carlos Andrés Satizabal R. Jaime Ricardo Cantera Kintz Paula Cristina sierra-Correa Marine and Coastal Research Institute (INVEMAR) Cerro Punta Betín Santa Marta Colombia Universidad del Valle Ecology of Estuaries and Mangroves Research Group (ECOMANGLARES) Cali Colombia

Although the importance of mangroves is clearly recognized around the world, these ecosystems are being strongly altered by the logging of their forests for multiple purposes. The Colombian Pacific coast is not an exception to this situation, and apart from the traditional logging of wood, the hunting of the Neotropical Cormorant or Pato-cuervo (Phalacrocorax brasilianus), an activity largely unknown but widespread in the region, is also causing the logging of great extensions of mangroves. The aim of this research was to determine if the assemblages of mollusks and crustaceans of these mangroves are being affected by the hunting of the cormorant. To answer this question, quantitative samplings were realized in four transects in logged and unlogged mangrove areas on the southwestern coast of the Colombian Pacific and diversity, equitability and dominance of macrofaunal assemblages of mangroves were calculated. The data show that although significant differences between diversity indices were not found, there were important differences in equitability (total J’: 0.55 in T1, 0.77 in T2, 0.46 in T3 and 0.65 in T4), specific dominance, and composition of species (T1: 11 species, T2: 13, T3: 9 and T4: 11) between logged and unlogged areas. Based on these results, although forest structure and interstitial salinity were different among transects, we conclude that the present practice of exploitation of the Neotropical Cormorant is affecting the epifaunal populations of mangroves, causing changes in the composition and dominance of species.

关键词： Mangrove Mollusks Crustaceans Neotropical Cormorant Colombian Pacific

Computational Simulation to Predict the Syngas Composition Produced during Charcoal Gasification

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Journal of Chemistry and Chemical Engineering 2014年第9期8卷 889-897页

作者： Ignacio Contreras-Andrade Santiago Ramirez-Rubio Jonathan Parra-Santiago Fabio sierra-Vargas carlos Alberto Guerrero-Fajardo Doctor Chemical Engineering Autonomous University of Sinaloa Culiacan Rosales 80040 Mexico Department of Aeronautical Engineering San Buenaventura University Bogota 11001 Colombia Chemical Engineering (C) National University of Colombia Bogota 11001 Colombia Oepartment of Mechanical Engineering National University of Colombia Bogota 11001 Colombia Chemical Engineering and Mechanical Master in Environmental Engineering PhD in Chemical Engineering National Universityof Colombia Bogota 11001 Colombia

Charcoal gasification could mitigate the energetic problems in the rural zones since these regions have considerable amounts of wood, which is the base of such a fuel available. This paper presents some CFD （computational fluid dynamic） predictions of the experimental results obtained from the fixed bed gasification of charcoal made in a pilot-scale downdraft reactor using air, which was designed and built by the Research Group in Clean Development Mechanisms and Energy Management, from the National University of Colombia. The quality of the syngas obtained from the process was evaluated through the CO and CO2 percentages measured in its composition. The performance at various air flow rates （measured at the system entrance, through an analog flow meter） is evaluated with the help of 11 thermocouples, which give the information to create a temperature profile, and three load cells to measure the solid fuel conversion rate. To simulate the process, the information from temperature profile, charcoal proximate analysis, air flow meter and load cells were taken as inputs and the syngas composition was obtained as the result from the calculation. The domain was defined as 2D with an axis-symmetric description, using quads as mesh elements. The calculation and results were performed in a CFD commercial code widely used for this type of simulations： ANSYS FLUENT. The predictions made by the software were validated with the experimental results obtained in the laboratory.

关键词： Biomass charcoal fixed bed gasification syngas CFD.

Ethanol Production Process by Lignocellulosic Material Fermentation from Water Hyacinth Biomass

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Journal of Chemistry and Chemical Engineering 2014年第12期8卷 1150-1155页

作者： Bianca Yadira Perez-Sarinana Jonathan Fabian sierra-Cantor Sergio Saldana-Trinidad carlos Alberto Guerrero-Fajardo Sebastian Pathiyamattom Joseph Renewable Energy Institute National Autonomous University of Mexico Temixco Morelos 62580 Mexico Department of Chemistry National University of Colombia Bogota 11001 Colombia Agroindustrial Engineering Polytechnic University of Chiapas Tuxtla Gutierrez 29082 Mexico

In order to take advantage of the lignocellulosic material in water hyacinth （Eichhornia crassipes）, dehydration pretreatment in the first step and then sodium hydroxide and hydrogen peroxide pretreatment was performed. The microorganism used for the fermentation process was Zimomonas mobilis. Batch fermentation experiments were carried out with four tests using 22 factorial design with two levels leadings to evaluate the effect of NaOH concentration, conditioning salts as independent variables and ethanol produced as a dependent variable. The optimum condition with higher amount of glucose hydrolyzed and ethanol was： substrate conditioning cellulases, it was pretreated 10% NaOH, with 92.38% conversion of glucose to ethanol and yield of 0.47 g ethanol per g of glucose and 0.018 g ethanol per g of biomass.

关键词： Fermentation lignocellulosic material water hyacinth ethanol