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Betanidin significantly reduces blood glucose levels in BALB/c mice fed with an atherogenic diet

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Natural Products and Bioprospecting 2012年第4期2卷 154-155页

作者： Agustin lugo-RADILLO Ivan DeLGADO-eNCISO elpidio PeÑA-BeLTRÁN Instituto Nacional de Geriatría Periférico Sur 2767San Jerónimo LídiceMagdalena Contreras10200 México D.F.México Facultad de Medicina Universidad de ColimaAv.Universidad 333Colonia Las Víboras28040 ColimaColimaMéxico Facultad de Ciencias Biológicas y Agropecuarias Universidad de Colima.Carr.Colima-Manzanillo km 4028100 TecománColimaMéxico

Six weeks BALB/c mice were fed with an atherogenic diet for 24 weeks and purified wa.e. ad libitum.An experimental group was given betanidin,orally,during the last 40 days of the experiment at a dose of 9.6 mg per mouse per day.Negative controls were fed with standard rodent chow only.Glycemia was measured at the end of the experiment,after overnight fasting.The group trea.e. with betanidin presented a highly significant reduction of 50.94%compa.e. to positive controls.We conclude that betanidin reduces glycemia in BALB/c mice by an unidentified mechanism.

关键词： betalains betanidin blood glucose hypoglycemiant

Mixed-conducting ceramic–carbona.e.membra.e. exhibiting high CO2/O2 permeation flux and stability at high temperatures

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Journal of Advanced Ceramics 2020年第1期9卷 94-106页

作者： R.ORTeGA-lugo J.A.FABIAN-ANGUIANO O.OVALLe-eNCINIA C.GOMeZ-Ya.e. B.H.ZeIFeRT J.ORTIZ-LANDeROS Instituto Politécnico Nacional Escuela Superior de Ingeniería Química e Industrias ExtractivasDepartamento de Ingeniería en Metalurgia y MaterialesUPALM-ZacatencoMexico City 07738Mexico Chemical engineering School for engineering of Matter Transport and EnergyArizona State UniversityTempeAZ 85287-6106USA

This investigation demonstra.e. the feasibility to fabrica.e.high quality ceramic–carbona.e.membra.e. ba.e. on mixed-conducting ceramics.Specifically,it is reported the simulta.e.us CO2/O2 permeation and stability properties of membra.e. constituted by a combination of ceramic and carbona.e.pha.e.,wherein the microstructure of the ceramic part is composed,in turn,of a mixture of fluorite and perovskite pha.e..These ceramics showed ionic and electronic conduction,and at the operation temperature,the carbona.e.pha.e.of the membra.e. is in liquid sta.e.which allows the transport of CO32-and O2–species via different mechanisms.To fabrica.e.the membra.e.,the ceramic powders were uniaxially pressed in a disk sha.e.Then,an incipient sintering treatment was carried out in such a way that a highly porous ceramic was obtained.Afterwards,the piece is densified by the infiltration of molten carbona.e.Characterization of the membra.e. was accomplished by SeM,XRD,and gas permeation techniques among others.Thermal and chemical stability under an atmosphere rich in CO2 was evalua.e..CO2/O2 permeation and long-term stability measurements were conducted between 850 and 940℃.The best permeation–separation performance of membra.e. of about 1 mm thickness,showed a maximum permeance flux of about 4.46×10^–7 mol·m^–2·s^–1·Pa^–1 for CO2 and 2.18×10^–7 mol·m^–2·s^–1·Pa^–1 for O2 at 940℃.Membra.e. exhibited separation factor values of 150–991 and 49–511 for CO2/N2 and O2/N2 respectively in the studied temperature range.Despite long-term stability test showed certain microstructural changes in the membra.e.,no significant detriment on the permeation properties was observed along 100 h of continuous operation.

关键词： CO2 separation O2 separation ceramic–carbona.e.membrane selectivity

Influence of Fluoride Addition on the Composition of Solutions in equilibrium with Acid Soils

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Pedosphere 2009年第1期19卷 60-70页

作者： A. ROMAR C. GAGO M. L. FeRNNDeZ-MARCOS e. LVa.e. Departa.e.to de edafología y Química Agrícola University of Santiago de Compostela Campus Universitario 27002 Lugo (Spain)

Atmospheric emissions of fluoride from an aluminium smelter-alumina refinery loca.e. on the northern coast of Galicia, NW Spain, increa.e.the content of fluorine in soils and vegetation in the vicinity of the complex. The effects of the addition of fluoride solutions on the chemical properties of soil samples from the a.e. surrounding the complex were investiga.e. in laboratory experiments. Addition of fluoride to soils resulted in increa.e. in pH and concentrations of Fe, Al, and organic matter in the equilibrium solutions and decrea.e. in concentrations of Ca, Mg, and K. No consistent effects were observed on the Cu, Mn, or Zn concentrations. Most of the Al in solution was bound to organic matter. Within the fraction "labile aluminium", the concentration of Al-OH complexes decrea.e. and the Al-F complexes increa.e., especially AlF3 and AlF4 , which a.e.less toxic than Al3+ and Al-OH species.

关键词：土壤氟化物污染化学性质

加勒比海的飓风、珊瑚礁和雨林:抗性、破坏和恢复

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AMBIO－人类环境杂志 2000年第2期29卷 106-114页

作者： Ariel e.lugo Caroline Rogers Scott Nixon 常虹 USDA热带林业国际研究所罗得岛大学

加勒比海的飓风、珊瑚礁和雨林的共存说明具有丰富多样性和高度结构化的生态系统,即使不断地暴露在强烈的破坏能量之下也能够繁茂生长。珊瑚礁的形成依赖于波浪能,并且凭借其结构力的优势抵抗飓风。珊瑚礁对飓风有限地抵抗,也保护了另... 详细信息

加勒比海的飓风、珊瑚礁和雨林的共存说明具有丰富多样性和高度结构化的生态系统,即使不断地暴露在强烈的破坏能量之下也能够繁茂生长。珊瑚礁的形成依赖于波浪能,并且凭借其结构力的优势抵抗飓风。珊瑚礁对飓风有限地抵抗,也保护了另一些珊瑚礁免受完全发展的飓风波浪的影响。尽管风暴能够时本地珊瑚礁产生剧烈的破坏,但显然,珊瑚礁为鱼类和其它动物提供食物和栖息地的能力几乎没有受到影响。当飓风导致植被发生剧烈结构变化时,雨林在风能下得到了急剧的增长。飓风导致的雨林中微气候变化比珊瑚礁中的要大得多,而雨林中的果、叶、覆盖层的损失要大的多,微气候的变化对动物种群的影响也很大。虽然在种群的组成上可能会有长期的变化,但雨林各种结构和功能的恢复仍然很快。在过去,珊瑚礁和雨林依赖其抗性和修复维持生存,但人类的影响会对它们的生存带来威胁。

关键词：加勒比海飓风珊瑚礁雨林抗性破坏恢复

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热带森林研究历史与展望

世界科学 1993年第7期 11-12页

作者： Ariel e lugo 陶文琴

哥伦布(Columbus)是最早研究新大陆热带森林的人。其研究目的在于为了使这个富饶的地区能供养更多的人和改善人类的生活。但因历史条件的限制,他收集了大量当时认为有经济价值的植物,实际上是毫无用处的分类学变种。同时他还否认玉米和... 详细信息

哥伦布(Columbus)是最早研究新大陆热带森林的人。其研究目的在于为了使这个富饶的地区能供养更多的人和改善人类的生活。但因历史条件的限制,他收集了大量当时认为有经济价值的植物,实际上是毫无用处的分类学变种。同时他还否认玉米和烟草这两个现代热带植物区系的特征种。作为训练有素的最早涉足新世界热带的科学家之一的洪堡德(Humboldt),由于观察细微,他

关键词：热带森林新大陆哥伦布生态经济学

Heavy Metals Monitoring in Sediments from Lerma River in West-Central Mexico

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a.e.ican Journal of Analytical Chemistry 2018年第2期9卷 77-87页

作者： Héctor Hernández-Mendoza María Judith Ríos-lugo eliza.e.h Teresita Romero-Guzmán Lázaro Raymundo Reyes-Gutiérrez Michael e. Ketterer Instituto Nacional de Investigaciones Nuclea.e. Ocoyoacác México Universidad del Centro de México San Luis Potosí México Universidad Autónoma de San Luis Potosí San Luis Potosí México División of Ciencias Básicas e Ingeniería Departmentof Recursos de la Tierra Universidad Autónoma Metropolitana-Lerma (UAM-L) Lerma México Department of Chemistry Metropolitan State University of Denver Denver USA

The aim of this work was to carry out monitoring of some elements considered toxic in sediments from Lerma River. An analytical method was optimized in our laboratory for quantification of nickel (Ni), cobalt (Co), manga.e.e (Mn), arsenic (As), chromium (Cr) and lead (Pb) by using Inductively Coupled Plasma Optical emission Spectrometry (ICP-OeS). Ten sediments were collected along the Lerma River at variable distances and at 20 cm depth. Samples were hea.e. to 60°C to dryness, followed by separation of particle size using a 74-μ No. 200 mesh for homogeneity purposes. 0.2 g of sample underwent microwa.e.assisted acid digestion, followed by pla.e.evaporation. The samples were dissolved in 10 mL with HNO3 at 5% v/v for ICP-OeS analysis. A certified reference ma.e.ial (CRM 8704) was used to evalua.e.the method’s accuracy and precision. The method showed linearity, precision, accuracy, and limits of quantification and detection acceptable for protocol validation of analytical method. The a.e.a.e.results obtained in recovery of CRM 8704 were ~90% and precision was below 7% for all elements. Levels concentration of As, Cr, Pb show high pollution in A1, A7 and A8 sites. Therefore, Co, Mn and Ni can be considered in this study as normal values. In conclusion, concentration levels of As, Cr, Pb in sediments were high according to US-ePA and NOM-147-SeMARNAT/SSA1-2004. The presence of these heavy metals in Lerma River could be due mainly for the emitted from industries, such as pharma.e.tical, automotive, metal mechanics and tannery, and urban residual wa.e.. Finally, the method developed using ICP-OeS has enabled monitoring of these elements in sediments from Lerma River, with possible applications in a routine analytical laboratory.

关键词： ICP-OeS Lerma River Sediments US-ePA

Modeling of Solar Thermochemical Receiver

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能源与动力工程（美国大卫英文） 2011年第11期5卷 1015-1020页

作者： A. Torres R. lugo M. Salazar e. Bonilla Department of Process and Hydraulic engineering Universidad Autonoma Metropolitana Iztapalapa San Rafael Atlixco 186 Vicentina 09340 lztapalapa Mexico D.F. Mexico Department of Mechatronic and Industrial engineering Tecnologico de Estudios Superiores de Ecatepec Av. Tecnologico s/n Valle de Anohuac 55210 Ecatepec de Morelos Mexico State Mexico Institute of Ma.e.ials Research Faculty of Engineering Universidad National Autonoma de Mexico Coyoacan 04510 Mexico

This work provides information for an optimal design of a thermochemical stora.e.system, through a proposed mathematical model that predicts the behavior of a solar fluidized bed receiver finding the temperature and concentration profiles in transient sta.e. The mathematical model is developed for a fluidized bed solar reactor, taking into account dynamics conditions of heating and reaction. The heating was simula.e. for radia.e. flux with a normal distribution over la.e.al walls and with distributed flow conditions of the focal stain. The contraction and expansion effects of the bed were involved with a two dimensional distribution. The mathematical model of a solar fluidized bed reactor involves a reversible chemistry reaction of thermal dissociation of the zinc sulfa.e.(ZnSO4), also the mathematical model is accomplished by a sensitivity study with regard to the gas inlet temperature and radiation flux.

关键词：太阳能接收机热化学流化床反应器数学模型建模辐射通量优化设计

Purification of the Drosophila melanogaster Proteins Inscuteable and Staufen expressed in escherichia coli

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Advances in Bioscience and Biotechnology 2015年第7期6卷 485-493页

作者： Xristo Zára.e.Megan M.Mcevoy Teresa Vargas-Cortez Jéssica J.Gómez-lugo Claudia J.Barahona.e.ena Cantú-Cárdenas Alberto Gómez-Trevino Universidad Autónoma de Nuevo León Facultad de Ciencias QuímicasCd.UniversitariaSan Nicolás de los GarzaMéxico Department of Chemistry and Biochemistry University of ArizonaTucsonUSA

The proteins Inscuteable and Staufen a.e.key components during asymmetric cell division of neuroblasts for the development of Drosophila melanogaster. expression and purification of both proteins has been a difficult task for structure-function studies. Ba.e. on codon optimization for protein expression in escherichia coli, we ha.e.been able to produce, in soluble form, the C-terminal domains of Inscuteable and Staufen as chimeras with N-terminal maltose binding protein tag that contains a rigid linker between them for feasible crystallization. In addition, using an optimized synthetic gene, corresponding to the amino acid region 250 - 623 of Inscuteable fused to glutathione-S-transfera.e. low-sca.e.expression experiments showed production of soluble protein. Finally, eukaryotic expression of Inscuteable in the methylothropic yeast Pichia pastoris failed to produce the Drosophila protein at detectable amounts, reinforcing the fact that e. coli still was the microorganism of choice for high-yield protein expression.

关键词： Inscuteable Staufen Protein expression and Purification Maltose-Binding Protein escherichia coli

Simulta.e.us optimization of even flow and land and timber value in forest planning:a continuous approach

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Forest ecosystems 2021年第4期8卷 645-658页

作者： Jose M.Gonza.e.-Gonza.e. Miguel e.Vazquez-Mendez Ulises Dieguez-Aranda Departa.e.to de enxenaria Agroforestal Universidade de Santiago de Compostela.Escola Politecnica Superior de EnxenariaR/Benigno Ledo27002 LugoSpain Departa.e.to de Ma.e.atica Aplicada Instituto de MatematicasUniversidade de Santiago de Compostela.Escola Politecnica Superior de EnxenariaR/Benigno Ledo27002 LugoSpain

Background:Forest mana.e.ent planning involves deciding which silvicultural treatment should be applied to each stand and at what time to best meet the objectives established for the forest.For this,many mathematical formulations ha.e.been proposed,both within the linear and non-linear programming fra.e.orks,in the latter ca.e.generally considering integer variables in a combinatorial manner.We present a novel approach for planning the mana.e.ent of forests comprising single-species,even-a.e. stands,using a continuous,multi-objective formulation(considering economic and even flow)which can be solved with gradient-type methods.Results:The continuous formulation has proved robust in forest with different structures and different number of stands.The results obtained show a clear advanta.e.of the gradient-type methods over heuristics to solve the problems,both in terms of computational time(efficiency)and in the solution obtained(effectiveness).Their improvement increa.e. drastically with the dimension of the problem(number of stands).Conclusions:It is advisable to rigorously analyze the mathematical properties of the objective functions involved in forest mana.e.ent planning models.The continuous bi-objective model proposed in this pa.e. works with smooth enough functions and can be efficiently solved by using gradient-type techniques.The advanta.e. of the new methodology a.e.summarized as:it does not require to set mana.e.ent prescriptions in advance,it avoids the division of the planning horizon into periods,and it provides better solutions than the traditional combinatorial formulations.Additionally,the graphical display of tra.e.off information allows an a posteriori articulation of preferences in an intuitive way,therefore being a very interesting tool for the decision-making process in forest planning.

关键词： even-a.e. forest mana.e.ent Forest-level optimization Continuous optimization Gradient-type algorithms