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A contribution to Pollen Rain characterization in Forest-Savanna Mosaics of the Venezuelan Guayana and Its Use in Vegetation Reconstructions from Sedimentary Records

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American Journal of Plant Sciences 2013年第7期4卷 33-52页

作者： Leal alejandra Bilbao Bibiana Berrío Juan carlos Department of Environmental Studies Universidad Simón Bolívar Sartenejas. Edo. Caracas Venezuela 2Department of Geo- graphy University of Leicester Leicester UK.

The main results of a study of pollen representation in surface soils from different plant communities in the upland savannas of Guayana were presented. The representation of savanna herb pollen mainly belonging to the Poaceae and cyperaceae was high in open communities such as fernlands, grasslands and Mauritia palm swamps, but decreased as vegetation structure became more closed and woody;from savanna-forest borders to secondary forests and lastly, evergreen montane forests;mimicking the gradient of vegetation openness observed in living plant communities. Thus, the proportion of savanna herb pollen in herbaceous communities: swamps, fernlands and grasslands, reached over 80% and arboreal pollen contributed less than 10%. This ratio changed in savanna-forest borders where savanna herb pollen decreased to 60% or less and the proportion of arboreal pollen rose to 30% or higher. Lastly, in forest soils, pollen abundances from trees (Dimorphandra, Protium, Schefflera), shrubs (Miconia and other Melastomataceae) and lianas contributed higher than 60% of the pollen sum, even in open gallery forests and fallows. The lack of pollen from cassava, the main crop in the forests of the region, at these sites was remarkable. The ordination of sediment samples from 4 records from the Late Holocene with respect to the soil surface samples studied, showed that the characterization of pollen rain was useful for identifying long-term compositional and structural changes in the sedimentary records, thus providing objective indicators for the interpretation of past vegetation structure.

关键词： Pollen Representation Savanna-Forest Dynamics Upland Guayana Gran Sabana Poaceae Pollen

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基于机器学习方法的预测效果分析：1998—2016年中国上市公司退市的证据

基于机器学习方法的预测效果分析：1998—2016年中国上市公司退市...

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作者： Karina alejandra Espinel cobos 厦门大学

学位级别：硕士

在过去的几十年里,中国作为世界第二大经济体,一直是学者和分析人士评估内部和外部金融冲击的焦点。企业财务困境便一直是重要关注点。因为在危机和灾难性事件之后,公司是此经济体中受影响较深的机构之一,它们也会因此不得不退出市场。... 详细信息

在过去的几十年里,中国作为世界第二大经济体,一直是学者和分析人士评估内部和外部金融冲击的焦点。企业财务困境便一直是重要关注点。因为在危机和灾难性事件之后,公司是此经济体中受影响较深的机构之一,它们也会因此不得不退出市场。本文比较了六种机器学习模式的性能,阐释1998-2016年期间中国沪深两市上市公司退市与否的二分类问题。本文样本包括2,863家公司,在分析中,它们被分成了训练、验证和测试三类数据集(50/25/25),用于对各个模型进行有效性的评估。相应地,本文比较了决策树(DT)、提升方法、随机森林(RF)、支持向量机(SVM)、逻辑回归和人工神经网络(ANN)等模型。本文使用前向逐步筛选法对国泰安数据库(cSMAR)财务报表中的偿付能力、比率结构、收益能力分析、工业经济部门、经营能力、现金流和增长率等44个财务比率指标进行变量选择。最终,本文选择了适合模型的24个财务指标,从而减少预测误差,并使得结果更为可靠。实证结果表明,随机森林和提升方法能提供最佳的预测性能,这两个方法的分类误差最小,并在AUc(ROc曲线)和召回率-准确率曲线的评估测量中表现出色。此外,本文应用了优于其他模型的随机森林,对变量的相对重要性进行分析。由此分析得出,对于预测中国企业退出的最重要的三个财务指标是ROA(资产收益率)、EBITDA/总负债和营业净利润率。

关键词：企业财务困境机器学习摘牌公司随机森林提升方法

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Production of camphene by Isomerization Reaction on Sulfated ZrO2

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chinese Journal of chemical Engineering 2000年第1期 68-71页

作者： Nora alejandra comelli,Omar Masini,Alfredo Lzaro carrascull,Esther Natalia Ponzi,Marta Isabel Ponzi INTEQUI(cONIcET-UNSL) Facultad de Ingenieriay ciencias Economico Sociales 25 de Mayo 384 V.Mercedes (SL) Argentina INTEQUI(cONIcET-UNSL) Facultad de Ingenieriay ciencias Economico Sociales 25 de Mayo 384 V.Mercedes (SL) Argentina INTEQUI(cONIcET-UNSL) Facultad de Ingenieriay ciencias Economico Sociales 25 de Mayo 384 V.Mercedes (SL) Argentina INTEQUI(cONIcET-UNSL) Facultad de Ingenieriay ciencias Economico Sociales 25 de Mayo 384 V.Mercedes (SL) Argentina cINDEcA(cONIcET-UNLP)calle 47 N°257 1900 La Plata Argentina

Abstract The kinetics of camphene production in liquid phase from α-pinene was experimentally determinedin an isothermal batch *** this end,a sulfated ZrO2catalyst was used and the reaction studied in thetemperature range of *** analyzing the experimental data,second reaction order for α-pinene wasfound.A kinetic model is presented which includes term for the catalyst load *** specific rate constant at393K was 2.19×10-3mol.L-1,min-1,the activation energy being *** Vaues are within the rangeof literature results.

关键词： camphene kinetics a-pinene zirconium oxide superacid catalyst

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Frontal penetrating arrow injury:A case report

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World Journal of clinical cases 2023年第17期11卷 4117-4122页

作者： alejandra Rodríguez-Ramos carlos A Zapata-castilleja José L Treviño-González Gerardo c Palacios-Saucedo Ramón G Sánchez-cortés Leonor G Hinojosa-Amaya Adriana Nieto-Sanjuanero Manuel de la O-cavazos Department of Pediatrics Hospital Universitario“Dr.JoséEleuterio González”Universidad Autónoma de Nuevo LeónMonterrey 64460Nuevo LeónMexico

BAcKGROUND Penetrating arrow injuries of the head and neck are exceedingly rare in pediatric *** pathology has high morbidity and mortality because of the presence of vital organs,the airway,and large ***,the treatment and removal of an arrow is a challenge that requires multidisciplinary *** SUMMARY A 13-year-old boy was brought to the emergency room after an arrow injury to the frontal *** arrowhead was lodged in the *** studies showed a lesion of the paranasal sinuses without compromising vital *** arrow was successfully removed by retrograde nasoendoscopy without complications,and the patient was *** Although rare,maxillofacial arrow injuries have high morbidity and mortality and require multidisciplinary management to preserve function and aesthetics.

关键词： Arrow Penetrating trauma Maxillofacial injuries Pediatrics Pediatric emergency medicine case report

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Performance of cold-preserved rat liver Microorgans as the biological component of a simplified prototype model of bioartificial liver

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World Journal of Hepatology 2016年第33期8卷 1442-1451页

作者： María Dolores Pizarro María Gabriela Mediavilla alejandra Beatriz Quintana ángel Luis Scandizzi Joaquín Valentín Rodriguez María Eugenia Mamprin centro Binacional de criobiología clínica y Aplicada Instituto de Biología Molecular y celular de Rosario consejo Nacional de Investigaciones científicas y Técnicas Morfología Facultad de Ciencias Bioquímicas y Farmacéuticas área Farma-cología Facultad de Ciencias Bioquímicas y FarmacéuticasUniversidad Nacional de Rosario

AIMTo develop a simplified bioartificial liver (BAL) device prototype, suitable to use freshly and preserved liver Microorgans (LMOs) as biological component. METHODSThe system consists of 140 capillary fibers through which goat blood is pumped. The evolution of hematocrit, plasma and extra-fiber fluid osmolality was evaluated without any biological component, to characterize the prototype. LMOs were cut and cold stored 48 h in BG35 and ViaSpan® solutions. Fresh LMOs were used as controls. After preservation, LMOs were loaded into the BAL and an ammonia overload was added. To assess LMOs viability and functionality, samples were taken to determine lactate dehydrogenase (LDH) release and ammonia detoxification capacity. RESULTSThe concentrations of ammonia and glucose, and the fluids osmolalities were matched after the first hour of perfusion, showing a proper exchange between blood and the biological compartment in the minibioreactor. After 120 min of perfusion, LMOs cold preserved in BG35 and ViaSpan® were able to detoxify 52.9% ± 6.5% and 53.6% ± 6.0%, respectively, of the initial ammonia overload. No significant differences were found with controls (49.3% ± 8.8%, P ® cold preserved LMOs, respectively (n = 6, P cONcLUSIONThis prototype relied on a simple design and excellent performance. It’s a practical tool to evaluate the detoxification ability of LMOs subjected to different preservation protocols.

关键词： Rat liver Microorgans cold preservation BG35 preservation solution Bioartificial liver device Acute liver failure

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Biological processes and signal transduction pathwaysregulated by the protein methyltransferase SETD7 and theirsignificance in cancer

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Signal Transduction and Targeted Therapy 2018年第1期3卷 137-150页

作者： Ines de Albuquerque Almeida Batista Luisa alejandra Helguero Institute for Biomedicine(iBiMED) Department of Medical SciencesUniversity of AveiroAveiroPortugal

Protein methyltransferases have been shown to methylate histone and non-histone proteins,leading to regulation of several biological processes that control cell *** the past few years,the histone-lysine N-methyltransferase SETD7(SETD7;also known as SET7/9,KIAA1717,KMT7,SET7,SET9)has emerged as an important regulator of at least 30 non-histone proteins and a potential target for the treatment of several human *** review discusses current knowledge of the structure and subcellular localization of SETD7,as well as its function as a histone and non-histone *** work also underlines the putative contribution of SETD7 to the regulation of gene expression,control of cell proliferation,differentiation and endoplasmic reticulum stress,which indicate that SETD7 is a candidate for novel targeted therapies with the aim of either stimulating or inhibiting its activity,depending on the cell signaling context.

关键词： homeostasis stimulating signal

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Effect of different anesthetic mixtures——ketamine-xylazine, ketamine-acepromazine and tiletamine-zolazepam——on the physiological and blood biochemistry parameters of male rhesus monkeys(Macaca mulatta) at different ages

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Animal Models and Experimental Medicine 2019年第2期2卷 83-97页

作者： Braulio Hernández‐Godínez Herlinda Bonilla Jaime Adrián Poblano Marcela Arteaga‐Silva Ameyalli Medina Hernández Armando contreras‐Uribe alejandra Ibanez-contreras Posgrado en ciencias Biológicas y de la Salud Unidad Iztapalapa Universidad Autónoma Metropolitana Ciudad de México México Investigación Biomédica Aplicada (INBIOMA) S.A.S. de c.V. Ciudad de México México Alimentos y camas Zoosanitarias (AcAZOO) S. de R.L. Ciudad de México México Departamento Biología de la Reproducción Unidad Iztapalapa Universidad Autónoma Metropolitana Ciudad de México México Laboratorio de Neurofisiología cognoscitiva Instituto Nacional de Rehabilitación Ciudad de México México

Background: Anesthetic agents are commonly utilized in the handling of non‐human primates for prevent the stress caused in physical exploration or physical restrain. For this reason, the objective of this work was to describe the effect of age and dissociative anesthetics (ketamine and tiletamine), and their combinations with acepromazine, xylazine and zolazepam, on the physiological and blood biochemical parameters in Macaca mulatta. Methods: Eighty male Macaca mulatta were divided into four experimental groups depending on the anesthetic mixture applied. Each group of 20 males was divided into five sub‐groups according to age. Physiological parameters were recorded every five minutes during a 30‐minute period. A blood sample was drawn to analyze blood biochemistry. Results: Statistical analyses revealed significant differences in the physiological parameters between the ketamine‐acepromazine and ketamine‐xylazine groups compared to the control group. The analysis of blood biochemistry found significant differences by age and by anesthetic mixture among all groups. conclusion: These findings contribute to standardizing this animal model in biological research.

关键词： acepromazine anesthesia blood biochemistry ketamine Macaca mulatta physiologic parameters tiletamine xylazine zolazepam

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Behavior of Heavy Metals during the Agro-Industrial Wastes Gasification

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Open Journal of Metal 2013年第2期3卷 1-7页

作者： Marcelo Echegaray Marianela costante alejandra Saffe carlos Palacios Rosa Rodriguez Instituto de Ingeniería Química Facultad de Ingeniería Universidad Nacional de San Juan Argentina

The characterization analysis of three agro-industrial wastes was performed in order to study its thermal gasification. Some analyses such as determination of ca, K and Mg concentration and determination of three representative toxic metals concentration cd, cr and Pb in all its oxidation states and the fundamental state, were carried out. The heavy metals concentration was also determined in the ashes obtained during the gasification process. The mobility of these elements was studied through three leaching tests. The behavior of heavy metals, sulfur and chlorine compounds, was predicted considering the presence of water vapor, syngas, ca, Mg, K, Si, Al and other ash components. The heavy metals are not more concentrated in the gasification ash;these pollutants are released during this process. ca, Mg and K presence in these residues would promote the pollutants retention. The ash of the studied waste can be disposed in controlled landfills or used in road construction, according to the obtained results during the leaching test DIN-DEV S4. The obtained results in the leaching test EPA 1311 TLcP classify these gasification ashes as no toxic waste.

关键词： Gasification Agro-Industrial Wastes Ash

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Effects of Supplementation with Increasing Levels of Energy concentrate on the Productive Response and Ruminal Digestion of Dairy cows Grazing Lucerne Pasture

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Agricultural Sciences 2018年第11期9卷 1487-1505页

作者： Eloy Eduardo Salado Gustavo Bretschneider alejandra cuatrin Gerardo Antonio Gagliostro Area de Investigación en Producción Animal Instituto Nacional de Tecnología Agropecuaria (INTA) Rafaela Argentina Agencia de Extensión Rural Necochea Instituto Nacional de Tecnología Agropecuaria (INTA) Necochea Argentin Area de Investigación en Producción Animal Instituto Nacional de Tecnología Agropecuaria (INTA) Balcarce Argentina

The aim of the study was to determine the effect of three levels of energy concentrate intake on dry matter (DM) and energy intake, milk yield and composition, rumen environment and pasture neutral detergent fiber (NDF) digestion. Twelve Holstein multiparous cows in early lactation (69.0 ± 5 days postpartum) producing 32.8 (±4.0) kg milk were assigned to three treatments at (kg/cow day) 3.5 (T3.5), 7.0 (T7.0) and 10.5 (T10.5) kg concentrate in a 3 × 3 Latin Square design. Parameters of ruminal environment and neutral detergent fiber (NDF) digestion were obtained using 3 additional rumen cannulated cows. concentrate was composed (as fed) by corn grain (68%), soybean meal (22%), wheat bran (8%) and a vitamin-mineral premix including monensin and thoroughly consumed. Yields (kg/cow day-1) of milk, 4% fat corrected milk (4% FcM 4%) and energy corrected milk (EcM) resulted higher (p p -1 without effects on yield of milk fat. concentrations (g/100 g) of milk fat (3.19), protein (2.97), total solids (11.75), non-fat solids (8.60) and casein (2.40) did not differ. Milk lactose content (g/100 g) was linearly increased (p p p p p crease in acetate and butyrate while the acetate: Propionate ratio remained unchanged. Pasture NDF digestion was affected as concentrate intake increased. To increase milk protein yield and reduce concentrations of N-NH3 in rumen and milk, feeding an energy concentrate at 41% of total DM intake resulted an effective tool.

关键词： Dairy cows concentrate Milk Yield Ruminal Digestion

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Historical perspective of cell transplantation in Parkinson's disease

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World Journal of Transplantation 2017年第3期7卷 179-192页

作者： alejandra Boronat-García Magdalena Guerra-crespo René Drucker-colín Departamento de Neuropatología Molecular Instituto de Fisiología CelularUniversidad Nacional Autónoma de México

cell grafting has been considered a therapeutic approach for Parkinson's disease(PD) since the 1980 s. The classical motor symptoms of PD are caused by the loss of dopaminergic neurons in the substantia nigra pars compacta, leading to a decrement in dopamine release in the striatum. consequently, the therapy of celltransplantation for PD consists in grafting dopamineproducing cells directly into the brain to reestablish dopamine levels. Different cell sources have been shown to induce functional benefits on both animal models of PD and human patients. However, the observed motor improvements are highly variable between individual subjects, and the sources of this variability are not fully understood. The purpose of this review is to provide a general overview of the pioneering studies done in animal models of PD that established the basis for the first clinical trials in humans, and compare these with the latest findings to identify the most relevant aspects that remain unanswered to date. The main focus of the discussions presented here will be on the mechanisms associated with the survival and functionality of the transplants. These include the role of the dopamine released by the grafts and the capacity of the grafted cells to extend fibers and to integrate into the motor circuit. The complete understanding of these aspects will require extensive research on basic aspects of molecular and cellular physiology, together with neuronal network function, in order to uncover the real potential of cell grafting for treating PD.

关键词： Parkinson’s disease cell replacement Animal models Nigrostriatal pathway Striatum Dopaminergic loss

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