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具有双储层结构的动态误差补偿回声状态网络
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作者 张昭昭 朱应钦 余文 《控制理论与应用》 EI CAS CSCD 北大核心 2024年第3期385-395,共11页
针对传统回声状态网络难以有效应对高阶非线性复杂模型问题,本文在理论分析的基础上提出了一种双储层结构的误差补偿回声状态网络,并设计了该网络的学习算法.该网络由计算层和补偿层构成,计算层主要承担拟合任务,补偿层则作为状态跟随器... 针对传统回声状态网络难以有效应对高阶非线性复杂模型问题,本文在理论分析的基础上提出了一种双储层结构的误差补偿回声状态网络,并设计了该网络的学习算法.该网络由计算层和补偿层构成,计算层主要承担拟合任务,补偿层则作为状态跟随器,实时补偿由于计算层对期望方差估计不足而导致的幅值偏差.对多阶振荡器和真实高阶非线性数据集的实验结果表明,本文所提网络结构较常规网络具有更高的稳定性和泛化性能,尤其对高阶非线性复杂模型的预测精度大幅度提升. 展开更多
关键词 回声状态网络 高阶非线性复杂模型 补偿回声状态网络 多阶振荡器
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The impact of maternal immune activation on the morphology and electrophysiological properties of postnatally-born neurons in the offspring
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作者 Emilio J.Galván Angelica Zepeda 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第2期399-400,共2页
Pregnancy comes with a combination of physical changes and physiological immunosuppression that increases the susceptibility of women to pathogens and in turn,rises the prevalence of infectious diseases.
关键词 PREVALENCE ACTIVATION impact
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Space-Time Chaos Filtering for the Incoherent Paradigm for 6G Wireless System Design from Theoretic Perspective
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作者 Valeri Kontorovich 《Communications and Network》 2024年第3期74-89,共16页
The following material is devoted to the generalization of the chaos modeling to random fields in communication channels and its application on the space-time filtering for the incoherent paradigm;that is the purpose ... The following material is devoted to the generalization of the chaos modeling to random fields in communication channels and its application on the space-time filtering for the incoherent paradigm;that is the purpose of this research. The approach, presented hereafter, is based on the “Markovian” trend in modeling of random fields, and it is applied for the first time to the chaos field modeling through the well-known concept of the random “treatment” of deterministic dynamic systems, first presented by A. Kolmogorov, M. Born, etc. The material presents the generalized Stratonovich-Kushner Equations (SKE) for the optimum filtering of chaotic models of random fields and its simplified quasi-optimum solutions. In addition to this, the application of the multi-moment algorithms for quasi-optimum solutions is considered and, it is shown, that for scenarios, when the covariation interval of the input random field is less than the distance between the antenna elements, the gain of the space-time algorithms against their “time” analogies is significant. This is the general result presented in the following. 展开更多
关键词 Chaotic Fields Variation (Functional) Derivatives Quasi-Optimum Algorithms for Chaotic Models
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Study of tree shrew biology and models: A booming and prosperous field for biomedical research
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作者 Yong-Gang Yao Li Lu +26 位作者 Rong-Jun Ni Rui Bi Ceshi Chen Jia-Qi Chen Eberhard Fuchs Marina Gorbatyuk Hao Lei Hongli Li Chunyu Liu Long-Bao Lv Kyoko Tsukiyama-Kohara Michinori Kohara Claudia Perez-Cruz Gregor Rainer Bao-Ci Shan Fang Shen An-Zhou Tang Jing Wang Wei Xia Xueshan Xia Ling Xu Dandan Yu Feng Zhang Ping Zheng Yong-Tang Zheng Jumin Zhou Jiang-Ning Zhou 《Zoological Research》 SCIE CSCD 2024年第4期877-909,共33页
The tree shrew(Tupaia belangeri)has long been proposed as a suitable alternative to non-human primates(NHPs)in biomedical and laboratory research due to its close evolutionary relationship with primates.In recent year... The tree shrew(Tupaia belangeri)has long been proposed as a suitable alternative to non-human primates(NHPs)in biomedical and laboratory research due to its close evolutionary relationship with primates.In recent years,significant advances have facilitated tree shrew studies,including the determination of the tree shrew genome,genetic manipulation using spermatogonial stem cells,viral vector-mediated gene delivery,and mapping of the tree shrew brain atlas.However,the limited availability of tree shrews globally remains a substantial challenge in the field.Additionally,determining the key questions best answered using tree shrews constitutes another difficulty.Tree shrew models have historically been used to study hepatitis B virus(HBV)and hepatitis C virus(HCV)infection,myopia,and psychosocial stress-induced depression,with more recent studies focusing on developing animal models for infectious and neurodegenerative diseases.Despite these efforts,the impact of tree shrew models has not yet matched that of rodent or NHP models in biomedical research.This review summarizes the prominent advancements in tree shrew research and reflects on the key biological questions addressed using this model.We emphasize that intensive dedication and robust international collaboration are essential for achieving breakthroughs in tree shrew studies.The use of tree shrews as a unique resource is expected to gain considerable attention with the application of advanced techniques and the development of viable animal models,meeting the increasing demands of life science and biomedical research. 展开更多
关键词 Tree shrew Animal model Neurodegenerative diseases Infectious diseases NEUROSCIENCE Phenome
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Epigenetic and Posttranscriptional Regulation in Retinoblastoma
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作者 Tovar-Hernández Karla Ruíz-Cruz Matilde Marco Antonio Meraz-Ríos 《Advances in Bioscience and Biotechnology》 2023年第4期190-209,共20页
The Retinoblastoma 1 (RB1) gene, located on chromosome 13q14 and encodes the tumor-suppressor retinoblastoma protein, is the cause of Retinoblastoma. The mutational inactivation of both gene alleles brings on this can... The Retinoblastoma 1 (RB1) gene, located on chromosome 13q14 and encodes the tumor-suppressor retinoblastoma protein, is the cause of Retinoblastoma. The mutational inactivation of both gene alleles brings on this cancer. Retinoblastoma (RB) high-risk histopathological characteristics indicate metastasis or local recurrence with rapid progresses following RB1 inactivation. There is growing interest in regulatory activities unconnected to the coding region of the genome, or exome, in addition to epigenetic control mechanisms. The altered epigenome is significant, though by no means the only, problem in the etiology of Retinoblastoma. After all, cancer development is a multistep process in which numerous dissimilar genetic, epigenetic, and posttranscriptional modifications result in a shared phenotype. This study emphasizes the most recent developments in posttranscriptional change and epigenetics related to retinoblastoma tumor biology. Here, we highlight the novel biomarkers the retinoblastoma tumor has expressed to improve patient survival. 展开更多
关键词 RETINOBLASTOMA EPIGENETIC ncRNAs MIRNAS lncRNAs circRNAs ceRNAs
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Why the Incoherent Paradigm Is for the Future Wireless Networks?
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作者 Valeri Kontorovich 《Communications and Network》 2023年第3期65-82,共18页
This material is aimed to attract attention to the “incoherent approach for power NOMA-RIS-MIMO transmission in wireless channels”. Such kind of approach might be successfully applied in future dense networks formed... This material is aimed to attract attention to the “incoherent approach for power NOMA-RIS-MIMO transmission in wireless channels”. Such kind of approach might be successfully applied in future dense networks formed by High-Speed Vehicles (HSV networks, etc.). Those scenarios take place in doubly selective communication channels typical for such kind of radio networks. The proposal for the presented hereafter incoherent view (“paradigm”) is based on several basic principles: 1) Shift from the “coherent “ideology”, i.e. rejection of the application of any type of Channel State Information (CSI, CSIT);2) Application of the so-called “invariant” to the communication channel’s features (distortions) modulation technique together with its incoherent demodulation;3) Orthogonal channel decomposition by means of “universal” eigen basis (in the form of Prolate Spheroidal Wave Functions, PSWF) as “artificial trajectories” of wave propagation;4) Chaotic filtering (chaos parameter settings as UE signatures) together with sequential multiuser parallel detection algorithms for users’ identification (classification). It is shown that the proposed approach might provide an effective use of the radio resource and it is relatively simple for implementation. 展开更多
关键词 Incoherent Processing Universal Eigen Functions Chaos Filtering Invariant Modulation
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Antifungal Potential of Beauveria bassiana on Solanum lycopersicum L. Infected with Fusarium oxysporum f. sp. lycopersici
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作者 Henry López-López Nancy Ruiz-Lau +6 位作者 Rocío Meza-Gordillo Víctor Manuel Ruiz-Valdiviezo Joseph Galthier Robledo-Luchetti Carlos Alberto Lecona-Guzmán Juan JoséVillalobos-Maldonado Luc Dendooven Joaquín Adolfo Montes-Molina 《Phyton-International Journal of Experimental Botany》 SCIE 2023年第4期1235-1255,共21页
The objective of this work was to evaluate the effect of Beauveria bassiana(Bb 1205)on controlling Fusarium oxysporum f.sp.lycopersici(Fol 17108)in tomato plants in greenhouse conditions.Inoculation of Bb 1205 was the... The objective of this work was to evaluate the effect of Beauveria bassiana(Bb 1205)on controlling Fusarium oxysporum f.sp.lycopersici(Fol 17108)in tomato plants in greenhouse conditions.Inoculation of Bb 1205 was the most promising among the agronomic variables and expression of the activity of the enzymesβ-1,3-glucanases and chitinases.Inoculation of Bb 1205 occurred at a concentration of 1×108 conidia·mL−1,which was administered onto the leaves,directly into the soil and via injection.Infection with Fol 17108 occurred with 1×106 spores·mL−1,which were added directly to the soil.Spectrophotometry was used for measuring agronomic parameters,namely activity of chitinases andβ-1,3-glucanases in foliage and roots.When Bb 1205 was added to the soil,the chlorophyll index and aerial part length showed significant differences.In addition,it was determined that root length,fresh weight of foliage,flower,and fruit count increased 82 days after inoculation(dai).Chitinase activity induced by Bb 1205 in leaves and roots of tomato plants infected with Fol 17108 was observed when injected into the stem at 32 dai(41.8 and 11.6-fold,respectively).Inoculation on the foliage showed a 10-fold increase ofβ-1,3-glucanases in the roots after 82 dpi.As for leaves,a 3.8-fold increase was found when the stem was inoculated.In the different in vivo applications,Bb 1205 activated its defenses by expressing the chitinase enzymes andβ-1,3-glucanase,thus reducing the damage caused by Fol 17108,demonstrating increase plant growth thereafter. 展开更多
关键词 MYCOPARASITISM agronomic parameters CHITINASES β-1 3-glucanases
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领导者–跟随者Thomson跳环系统的自抗扰控制设计(英文) 被引量:4
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作者 Mario RAMIREZ-NERIA José L GARCIA-ANTONIO +2 位作者 Hebertt J SIRA-RAMIREZ Martin VELASCO-VILLA Rafael CASTRO-LINARES 《控制理论与应用》 EI CAS CSCD 北大核心 2013年第12期1564-1572,共9页
将用电磁方法悬浮起来的一对环构成领导者–跟随者系统实现对光滑参考轨线的跟踪要求.这一任务通过设计具有对扰动进行在线估计与补偿功能的自抗扰控制器(ADRC)实现.本文设计方法与传统ADRC的主要不同在于领导者和跟随者的跟踪控制器设... 将用电磁方法悬浮起来的一对环构成领导者–跟随者系统实现对光滑参考轨线的跟踪要求.这一任务通过设计具有对扰动进行在线估计与补偿功能的自抗扰控制器(ADRC)实现.本文设计方法与传统ADRC的主要不同在于领导者和跟随者的跟踪控制器设计都是基于平坦输出的线性化近似系统.超出线性化近似有效区域的大的高度偏差所导致的未知非线性则被视为扰动,这个扰动借助于线性扩张观测器进行在线估计并通过线性反馈控制器进行消除.实验结果检验了本文所提方法的有效性. 展开更多
关键词 Thomson跳环 自抗扰控制 广义比例积分(GPI)观测器 领导者-跟随者布局
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Contrasting initial events of localized corrosion on surfaces of 2219-T42 and 6061-T6 aluminum alloys exposed in Caribbean seawater 被引量:7
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作者 Gloria ACOSTA Lucien VELEVA +1 位作者 Juan Luis LóPEZ D.A.LóPEZ-SAURI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2019年第1期34-42,共9页
Aluminum alloy samples, 6061-T6 and 2219-T42, were exposed to Caribbean seawater for 90 d. The fluctuations of open circuit potential, considered as electrochemical noise (EN), were used to characterize and compare in... Aluminum alloy samples, 6061-T6 and 2219-T42, were exposed to Caribbean seawater for 90 d. The fluctuations of open circuit potential, considered as electrochemical noise (EN), were used to characterize and compare initial pitting events, which appeared on their surfaces. EN analysis was carried out using the power spectral density (PSD) vs frequency. The decrease of the β exponent in PSD graphs indicated a release of spontaneous energy with the progress of pit formation in seawater. The fluctuations were associated with the breakdown and formation of new corrosion layers. The values of β exponent in PSD graphs suggest that corrosion process of AA2219-T42 alloy occurs as a persistent non-stationary process, the dynamics of which is controlled by fractional Brownian motion (fBm), while on AA6061-T6 alloy the corrosion process was dominated by stationary and weakly persistent features, with the contribution of fractional Gaussian noise (fGn). After the exposure in seawater, SEM-EDX analysis revealed insoluble intermetallic particles on the alloys, rich in Cu or Fe and irregularly distributed. The preferential dissolution of Mg and Al occurs from the S-phase (Al2CuMg) of AA2219-T42 alloy. 展开更多
关键词 aluminum alloy CORROSION electrochemical noise intermetallic particles seawater
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Effect of phacoemulsification on intraocular pressure in patients with primary open angle glaucoma and pseudoexfoliation glaucoma 被引量:7
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作者 Jesus Jimenez-Roman Gabriel Lazcano-Gomez +6 位作者 Karina Martínez-Baez Mauricio Turati Rosario Gulías-Canizo Luis F.Hernández-Zimbrón Lenin Ochoa-De la Paz Rubén Zamora Roberto Gonzalez-Salinas 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2017年第9期1374-1378,共5页
AIM:To compare the effect of phacoemulsification on intraocular pressure(IOP)in patients with primary open angle glaucoma(POAG)and pseudoexfoliation glaucoma(PXG).METHODS:A retrospective comparative case serie... AIM:To compare the effect of phacoemulsification on intraocular pressure(IOP)in patients with primary open angle glaucoma(POAG)and pseudoexfoliation glaucoma(PXG).METHODS:A retrospective comparative case series conducted at the Glaucoma Department at the Association to Prevent Blindness in Mexico.The study enrolled consecutive patients having phacoemulsification with intraocular lens(IOL)implantation and a diagnosis of POAG or PXG.Data about IOP values and number of glaucoma medications used was collected at baseline,1,3,6 and12mo postoperatively.RESULTS:The study enrolled 88 patients(88 eyes).After phacoemulsification,there was a statistically significant reduction in IOP values and glaucoma medications use compared to baseline in both POAG and PXG patients(P〈0.001).In the POAG group,a 20%decrease in IOP values was evidenced,and a 56.5%reduction in the number of medications used at the one-year follow-up.The PXG group showed a 20.39%,and a 34.46%decrease in IOP and number of medications used,respectively.A significant difference in the meanΔIOP(postoperative changes in IOP)was evidenced between groups(P=0.005).The reduction of the postsurgical IOP mean values in both groups,the POAG group showed a greater reduction in IOP values compared to the PXG group.CONCLUSION:In both types of glaucoma,phacoemulsification cataract surgery can result in a significant IOP reduction(20%)over a 12mo follow-up period.The number of medications used is also significantly reduced up to 12mo after surgery,especially in the PXG group. 展开更多
关键词 cataract surgery pseudoexfoliation glaucoma secondary glaucoma primary open angle glaucoma INTRAOCULARPRESSURE
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Role of GSK3<i>β</i>and PP2A on Regulation of Tau Phosphorylation in Hippocampus and Memory Impairment in ICV-STZ Animal Model of Alzheimer’s Disease 被引量:3
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作者 Teresa Ponce-Lopez Enrique Hong +1 位作者 Manuel Abascal-Díaz Alfredo Meneses 《Advances in Alzheimer's Disease》 2017年第1期13-31,共19页
Intracerebroventricular administration (ICV) of streptozotocin (STZ) in rats has been associated to desensitization of the insulin receptor (IR) and biochemical changes similar to those occurring in Alzheimer’s disea... Intracerebroventricular administration (ICV) of streptozotocin (STZ) in rats has been associated to desensitization of the insulin receptor (IR) and biochemical changes similar to those occurring in Alzheimer’s disease (AD) or older brains, so it has been proposed as a suitable model for studying some of the pathological features of AD sporadic type (SAD). In this study, we investigated the role of glycogen synthase kinase 3β (GSK3β) and protein phosphatase 2A (PP2A) in the regulation of the phosphorylation of tau (p-tau). Results showed that ICV-STZ treated rats had deficits in short- (1.5-h) and long-term (24- and 48-h) memory after one month of ICV-STZ treatment and six months relative to control rats. The memory deficit was associated to increasing [F(3, 12) = 31.48, p β (p-GSK3β) and PP2A in hippocampus and PFC, indicating that GSK3β and PP2A contributed to regulation of p-tau. These data supporting the model with ICV-STZ in rat are adequate to study the progressive memory impairment associated to hyperphosphorylation of tau and the cascade of insulin receptor signaling;confirm that phosphatidyl-inositol-3 kinase-protein kinase B (PI3K-PKB/Akt-GSK3β) and PP2A are involved in the modulation of proteins responsible for the regulation of neurodegeneration in AD. 展开更多
关键词 Memory Deficit Tau HYPERPHOSPHORYLATION GSK3β PP2A Streptozotocin HIPPOCAMPUS
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Comparative study on simultaneous removal of calcium and sulfate ions from flotation recycling water by aluminum hydroxide 被引量:2
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作者 Ángel Daniel GUERRERO-FLORES Martha Araceli ELIZONDO-ÁLVAREZ +1 位作者 JoséManuel FLORES-ÁLVAREZ Alejandro URIBE-SALAS 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第7期2379-2390,共12页
Due to the environmental policies and economic reasons,the water used in some flotation operations of complex sulfide ores is recirculated,causing the ion concentration of some species to increase over time,affecting ... Due to the environmental policies and economic reasons,the water used in some flotation operations of complex sulfide ores is recirculated,causing the ion concentration of some species to increase over time,affecting the flotation of the minerals of interest.In this work,an experimental and thermodynamic analysis of the synthetic solutions was presented with a high content of calcium and sulfate ions.The study focused on evaluating the use of two aluminum compounds for the precipitation of Ca^(2+)and SO_(4)^(2−)in the form of ettringite.The amorphous aluminum hydroxide was found to be more efficient than the crystalline one,giving rise to 83%calcium and 91%sulfate removal.The XRD analysis of the solids showed the main reaction product of ettringite,accompanied by small amounts of calcite,due to the absorption of atmospheric carbon dioxide.The final solution after the chemical treatment showed residual calcium and sulfate concentrations below 200 mg/L.Finally,the kinetics of calcium removal appeared to correspond to a second order reaction with respect to calcium concentration,with an apparent activation energy of 53.48 kJ/mol,which may suggest that the ettringite precipitation process is governed by the chemical reaction. 展开更多
关键词 ETTRINGITE ion removal aluminum hydroxide CALCIUM SULFATE
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Characterization by EBSD of Antimony-calcium Rich Phases Formed during Purification of Aluminum Scrap 被引量:1
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作者 MUIZ Rodrigo FLORES Alfredo +4 位作者 ORTIZ Juan RODRíGUEZ Nelly MARTíNEZ Fernando LUNA Jesús OROZCO Pilar 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2013年第4期647-649,共3页
We studied the influence of antimony on the modification rate of the silicon eutectic with sodium and/or strontium for castiig of A1-Si alloys, and introduced controlled Ca and Sb to the system and studied the resulti... We studied the influence of antimony on the modification rate of the silicon eutectic with sodium and/or strontium for castiig of A1-Si alloys, and introduced controlled Ca and Sb to the system and studied the resulting compounds, which were determined to be CazSb and A1Sb. Scanning electron microscopy together with the complementary technique of electron backscatter diffraction (EBSD) were used to characterize the materials. The experimental results provided the basis for us to establish that antimony removal from AI occurs mainly through the reaction (Sb)A1 + 2Ca = Ca^Sb + A1. 展开更多
关键词 aluminum alloys antimony contamination modification
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Vibrational Stabilization by Reshaping Arnold Tongues: A Numerical Approach 被引量:1
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作者 Joaquin Collado Hildeberto Jardón-Kojakhmetov 《Applied Mathematics》 2016年第16期2005-2020,共16页
This paper presents two contributions to the stability analysis of periodic systems modeled by a Hill equation: The first is a new method for the computation of the Arnold Tongues associated to a given Hill equation w... This paper presents two contributions to the stability analysis of periodic systems modeled by a Hill equation: The first is a new method for the computation of the Arnold Tongues associated to a given Hill equation which is based on the discretization of the latter. Using the proposed method, a vibrational stabilization is performed by a change in the periodic function which guarantees stability, given that the original equation has unbounded solutions. The results are illustrated by some examples. 展开更多
关键词 Vibrational Stabilization Hill Equation Periodic Systems Arnold Tongues
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Nucleation of Fe-Rich Intermetallic Phases on α-Al_(2)O_(3) Oxide Films in Al-Si Alloys 被引量:2
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作者 Pilar Orozco-Gonzalez Manuel Castro-Roman +6 位作者 Simitrio Maldonado-Ruiz Sergio Haro-Rodriguez Fabian Equihua-Guillen Rodrigo Muniz-Valdez Salvador Luna-Alvarez Miguel Montoya-Davila Alejandra Hernandez-Rodriguez 《Journal of Minerals and Materials Characterization and Engineering》 2015年第1期15-25,共11页
Nucleation of Fe-rich intermetallic phases on α-Al2O3 oxide films was analyzed in five experimental Al-Fe-Mn-Si alloys. In an attempt to verify the role of α-Al2O3 films in nucleating Fe-rich intermetallics, experim... Nucleation of Fe-rich intermetallic phases on α-Al2O3 oxide films was analyzed in five experimental Al-Fe-Mn-Si alloys. In an attempt to verify the role of α-Al2O3 films in nucleating Fe-rich intermetallics, experiments have been conducted under conditions where formed in situ oxide films were present. Some Fe-rich intermetallics are observed to be related with the oxide films in the microstructure, the present results are in accordance with some research that suggest that the Fe-rich intermetallic phases nucleate upon the oxide films. The intermetallic phases and α-Al2O3 films were unambiguously identified with the help of complementary techniques such as thermal analysis, SEM/EDS and X-ray diffraction. 展开更多
关键词 Aluminum Alloys INTERMETALLICS NUCLEATION Crystal Growth Oxide Films
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Effect of Copper and Iron on Acidogenic Biomass in an Anaerobic Packed Bed Reactor 被引量:1
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作者 Gonzalo M. Figueroa-Torres Maria T. Certucha-Barragán +5 位作者 Francisco J. Almendariz-Tapia Onofre Monge-Amaya Evelia Acedo-Félix Martín I. Pech-Canul Ana L. Leal-Cruz Carlos I. VillaVelázquez-Mendoza 《Advances in Bioscience and Biotechnology》 2014年第6期564-571,共8页
The aim of this study was to evaluate the effect of copper and iron on acidogenic biomass immobilized on clinoptilolite in an anaerobic packed bed reactor. Copper and iron were fed to the reactor at concentrations of ... The aim of this study was to evaluate the effect of copper and iron on acidogenic biomass immobilized on clinoptilolite in an anaerobic packed bed reactor. Copper and iron were fed to the reactor at concentrations of 100 and 300 mg&middotL-1, respectively. Both metal ions had insignificant inhibitory effect over the metabolism of the biomass, specifically, on substrate consumption and production of volatile fatty acids (VFAs). The microstructural characterization of the biofilm by Scanning Electron Microscopy showed no effect on the morphology of the microorganisms after the metals treatment. Copper and iron removal was also measured in the reactor, achieving a breakthrough time of 3 days, during which removal efficiencies were higher than 90%. It was also observed that the biomass had a greater affinity for copper. The results indicate that acidogenic biomass can be used effectively as a sorbent agent. The pollution of river-streams with heavy metals—mainly copper and iron—was one of the most compelling motivations for conducting this investigation. The San Pedro River Basin, a trans-boundary river that originates near the mining town of Cananea, Sonora, México, and flows to Arizona, USA, exemplifies this environmental issue. 展开更多
关键词 ACIDOGENESIS ANAEROBIC Digestion BIOMASS COPPER IRON CLINOPTILOLITE
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Improved Representation of Biological Information by Using Correlation as Distance Function for Heatmap Cluster Analysis
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作者 Axel Tiessen Edgar A. Cubedo-Ruiz Robert Winkler 《American Journal of Plant Sciences》 2017年第3期502-516,共15页
Heatmap cluster figures are often used to represent data sets in the?omic sciences. The default option of the frequently used R heatmap function is to cluster data according to Euclidean distance, which groups data ma... Heatmap cluster figures are often used to represent data sets in the?omic sciences. The default option of the frequently used R heatmap function is to cluster data according to Euclidean distance, which groups data mainly to their numerical value and not to its relative behaviour. The disadvantage of using the default clustering?dendrograms of R is demonstrated. Instead, a script is provided that uses correlation as distance function, which better reveals biologically meaningful information. This optimized script was used to detect heterotic groups in Vitamaize hybrids (purple maize with high nutraceutical value). A field trial with different genetic combinations was performed through an agricultural phenomics approach (holistic evaluation of the phenotype). The grain yield data and other phenotypic variables were represented through heatmap figures. In the data set of Mexican tropical maize germplasm, at least three heterotic groups were detected, in contrast to only two heterotic groups reported earlier in temperate yellow maize from USA and Europe. This optimized script for heatmap correlation bicluster can also be used to better represent metabolomic fingerprints and transcriptomic data sets. 展开更多
关键词 Clusters CORN Dendogram Grain Yield HETEROSIS Hybrid VIGOUR Plant Breeding PHENOTYPING Pearson CORRELATION Coefficient ZEA mays
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Kinetic and Thermodynamic Study of Arsenic (V) Adsorption on P and W Aluminum Functionalized Zeolites and Its Regeneration
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作者 Adriana Medina Ramírez Prócoro Gamero Melo +3 位作者 José Manuel Almanza Robles María Esther Sánchez Castro Sasirot Khamkure Roberto García de León 《Journal of Water Resource and Protection》 2013年第8期58-67,共10页
In the “Laguna” region of Coahuila state, Mexico like other places in the world, the groundwater needs to be treated to meet the quality required for human consumption. The study had probed that a Mexican fly ash ca... In the “Laguna” region of Coahuila state, Mexico like other places in the world, the groundwater needs to be treated to meet the quality required for human consumption. The study had probed that a Mexican fly ash can be used as a raw material to obtain effective low cost adsorbents for drinking water treatment, as well evaluated the effects of pH, ion coexistence, dose, arsenic (As) concentration and temperature on the As(V) uptake by using P and W modified zeolites (PMOD and WMOD) obtained from a Mexican fly ash. The As(V) adsorption capacity of the WMOD zeolite was not affected by pH and As(V) concentrations in aqueous solution was achieved 0.01 mg/L in the studied pH range;however, the As(V) removal by using PMOD zeolite decreased at high pH values. Carbonate concentration had a negative effect on the As(V) uptake of both zeolites but this effect was higher for the PMOD zeolite. The maximum adsorption capacities (Qmax) were 76.11 and 44.44 mg of As(V)/g of zeolite for the WMOD and the PMOD zeolites, respectively. The adsorption process was endothermic, spontaneous and occurred by chemical exchange. The experimental data were best interpreted by a pseudo-second order kinetic model. The WMOD zeolite showed a higher adsorption capacity and rate than the PMOD even at the highest evaluated As(V) concentration. The adsorption capacity of the regenerated WMOD zeolite was similar to the original zeolite. Because of the high As(V) adsorption capacity, chemical stability and regenerability, the WMOD zeolite is potentially useful as low-cost adsorbent for As(V) removal from aqueous effluents. 展开更多
关键词 FLY Ash Zeolite ARSENIC (V) Removal ADSORBENT REGENERATION
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DNA Fidelity: Expression of a Monocot Promoter in a Dicot Plant
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作者 Luis María Suárez-Rodríguez Hugh Mason +4 位作者 Joel Ramírez-Cabrera Luis Jorge Saucedo Miguel Angel Gómez-Lim Charles Arntzen Rodolfo López-Gómez 《American Journal of Plant Sciences》 2022年第1期50-59,共10页
The knowledge generated from the identification of plant promoters has been very important for plant biotechnology development. The use of promoters in transgenic plants allows a reasonable level of regulating protein... The knowledge generated from the identification of plant promoters has been very important for plant biotechnology development. The use of promoters in transgenic plants allows a reasonable level of regulating protein expression. With the application of reporter genes, such as <i>gus</i>A (<i>uid</i>A,) the production of a colored protein, <i>β</i>-glucuronidase, can be detected and measured both qualitatively and quantitatively, and the activity of the promoter can be assessed. In this work we use a promoter of an abundant banana fruit protein gene <i>Musa acuminata</i> Acidic Chitinase class III a monocot species, to drive expression of <i>gus</i>A in a dicot species, like tomato. We evaluated the monocot promoter capabilities by localizing and quantifying <i>β</i>-glucuronidase (GUS) expression through fluorometric assays during tomato fruit ripening. Our results suggest that this promoter could be used for specifically strong fruit protein expression in dicot plants. 展开更多
关键词 PROMOTER Fruit RIPENING Tomato BANANA
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Renin-angiotensin system blockade: Effect on renal mRNA expression in 5/6 nephrectomized rats
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作者 Erika Yadira Cruz-Laguna Ana Ma. Gámez-Méndez +3 位作者 Hilda Vargas-Robles Amelia Ríos Alfonso Méndez-Tenorio Bruno Escalante 《Health》 2013年第4期9-15,共7页
The aim of this study was to determinate the gene expression levels of angiotensinogen, angiotensin converting enzyme, renin, (pro)renin receptor, and the final rennin-angiotensin system (RAS) products Angiotensin (An... The aim of this study was to determinate the gene expression levels of angiotensinogen, angiotensin converting enzyme, renin, (pro)renin receptor, and the final rennin-angiotensin system (RAS) products Angiotensin (Ang) II and Ang 1-7 inthe remnant kidney of 5/6 nephrectomized rats and its response to RAS pharmacological blockade. Male Wistar rats were divided into five groups: sham operated (SO), 5/6 nephrectomized (NFX), NFX + captopril (50 mg/ kg/day), NFX + losartan (10 mg/kg/day), and NFX + aliskiren (10 mg/kg/day). Animals were followed up for 60 days and protein urine excretion was measured. Systolic blood pressure, renal tissue RAS mRNA expression levels, plasma Ang II, and plasma Ang 1-7 were evaluated at day 60 after nephrectomy. Blood pressure and urine protein were increased after 5/6 nephrectomy. Ang II levels were increased 9.4 fold, whereas Ang 1-7 decreased 72.9% in NFX animals compared with SO rats. 5/6 nephrectomy increased renal angiotensinogen and (pro)renin receptor mRNA expression but down-regulated renin mRNA expression. RAS blockade restored the systolic blood pressure to normal values and slowed down urinary protein excretion, and also prevented changes in Ang II and Ang 1-7. RAS blockade reduced (pro)renin receptor, ACE, and AGT mRNA expression in the remnant kidney. However, renin mRNA expression increased compared with NFX rats. In conclusion these results suggest that inhibition of Ang II synthesis by RAS blockade is associated with renal regulation of RAS mRNA expression and this may be through a mechanism related with the Ang II/Ang 1-7 balance. 展开更多
关键词 ANGIOTENSIN II ANGIOTENSIN 1-7 ACE RAS BLOCKADE
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