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A Decomposition of a Complete Graph with a Hole

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Open Journal of Discrete Mathematics 2021年第1期11卷 1-12页

作者： Roxanne Back alejandra Brewer Castano Rachel Galindo Jessica Finocchiaro Florida Southern College Lakeland USA University of Colorado Boulder USA

In the field of design theory, the most well-known design is a Steiner Triple System. In general, a G-design on H is an edge-disjoint decomposition of H into isomorphic copies of G. In a Steiner Triple system, a complete graph is decomposed into triangles. In this paper we let H be a complete graph with a hole and G be a complete graph on four vertices minus one edge, also referred to as a . A complete graph with a hole, , consists of a complete graph on d vertices, , and a set of independent vertices of size v, V, where each vertex in V is adjacent to each vertex in . When d is even, we give two constructions for the decomposition of a complete graph with a hole into copies of : the Alpha-Delta Construction, and the Alpha-Beta-Delta Construction. By restricting d and v so that , we are able to resolve both of these cases for a subset of using difference methods and 1-factors.

关键词： Graph Decomposition Combinatorial Design Complete Graph with a Hole

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

Synthesis of Temperature- and pH-Sensitive Graft Copolymer Containing 2-(Diethylamino)ethyl Methacrylate and N-Vinylcaprolactam onto Silicone Rubber

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Open Journal of Polymer Chemistry 2016年第3期6卷 15-26页

作者： alejandra Jiménez-Morales Alejandro Ramos-Ballesteros Emilio Bucio Departamento de Química de Radiaciones y Radioquímica Instituto de Ciencias Nucleares Universidad Nacional Autónoma de México Circuito Exterior Ciudad Universitaria México DF México

Silicone rubber films were modified by the consecutive grafting of 2-(diethylamino)ethyl methacrylate (DEAEMA) and N-vinylcaprolactam (NVCL) using direct method on two steps with gamma-rays. The effect of absorbed dose and monomer concentration on grafting degree was determined. The grafted samples were verified by FTIR-ATR spectroscopy and swelling;thermal properties were analyzed by DSC and TGA. The stimuli-responsive behavior was studied by swelling and/or DSC. Thermo- and pH-sensitive films of (PP-g-DEAEMA)-g-NVCL presented a pH critical at 3.2 and LCST around 63.5℃.

关键词： Radiation-Grafting Smart Polymers 2-(Diethylamino)ethyl Methacrylate N-Vinylcaprolactam

The opening of maitotoxin-sensitive calcium channels induces the acrosome reaction in human spermatozoa： differences from the zona pellucida

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Asian Journal of Andrology 2011年第1期13卷 159-165页

作者： lulio C Chaivez Gerardo A de Blas Josd L de la Vega-Beltran Takuya Nishigaki Mayel Chirinos Maria Elena Gonzaez-Gonzalez Fernando Larrea alejandra Soiis Alberto Darszon Claudia L Trevino Department of Developmental Genetics and Molecular Physiology Biotechnology Institute UNAM Cuernavaca Mexico Department of Reproduction Biology National Institute of Medical Sciences and Nutrition ＇Salvador Zubiran＇ Mexico City Mexico

The acrosome reaction （AR）, an absolute requirement for spermatozoa and egg fusion, requires the influx of Ca2＋ into the spermatozoa through voltage-dependent Ca2＋ channels and store-operated channels. Maitotoxin （MTx）, a Ca2＋-mobilizing agent, has been shown to be a potent inducer of the mouse sperm AR, with a pharmacology similar to that of the zona pellucida （ZP）, possibly suggesting a common pathway for both inducers. Using recombinant human ZP3 （rhZP3）, mouse ZP and two MTx channel blockers （U73122 and U73343）, we investigated and compared the MTx- and ZP-induced ARs in human and mouse spermatozoa. Herein, we report that MTx induced AR and elevated intracellular Ca2＋（[Ca2＋]~） in human spermatozoa, both of which were blocked by U73122 and U73343. These two compounds also inhibited the MTx-induced AR in mouse spermatozoa. In disagreement with our previous proposal, the AR triggered by rhZP3 or mouse ZP was not blocked by U73343, indicating that in human and mouse spermatozoa, the AR induction by the physiological ligands or by MTx occurred through distinct pathways. U73122, but not U73343 （inactive analogue）, can block phospholipase C （PLC）. Another PLC inhibitor, edelfosine, also blocked the rhZP3- and ZP-induced ARs. These findings confirmed the participation of a PLC-dependent signalling pathway in human and mouse zona protein-induced AR. Notably, edelfosine also inhibited the MTx-induced mouse sperm AR but not that of the human, suggesting that toxin-induced AR is PLC-dependent in mice and PLC-independent in humans.

关键词： acrosome reaction calcium channels human sperm maitotoxin mouse sperm

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

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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...

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

Senescent mesenchymal stem/stromal cells in pre-metastatic bone marrow of untreated advanced breast cancer patients

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Oncology Research 2023年第3期31卷 361-374页

作者： FRANCISCO RAÚL BORZONE MARÍA BELÉN GIORELLO LEANDRO MARCELO MARTINEZ MARÍA CECILIA SANMARTIN LEONARDO FELDMAN FEDERICO DIMASE EMILIO BATAGELJ GUSTAVO YANNARELLI NORMA alejandra CHASSEING Laboratorio de Inmunohematología Instituto de Biología y Medicina Experimental(IBYME)Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET)Buenos AiresArgentina Division of Hematology and Medical Oncology Department of MedicineWeill Cornell Medical CollegeNew YorkUSA Laboratorio de Regulación Génica y Células Madre Instituto de Medicina TraslacionalTrasplante y Bioingeniería(IMeTTyB)Universidad Favaloro-CONICETBuenos AiresArgentina Facultad de Ciencias de la Salud Universidad Nacional del Centro de la Provincia de Buenos Aires(UNCPB)TandilBuenos AiresArgentina Servicio de Hematología Hospital Militar CentralBuenos AiresArgentina Servicio de Oncología Hospital Militar CentralBuenos AiresArgentina

Breast cancer is the predominant form of carcinoma among women worldwide,with 70%of advanced patients developing bone metastases,with a high mortality *** this sense,the bone marrow(BM)mesenchymal stem/stromal cells(MSCs)are critical for BM/bone homeostasis,and failures in their functionality,transform the BM into a premetastatic niche(PMN).We previously found that BM-MSCs from advanced breast cancer patients(BCPs,infiltrative ductal carcinoma,stage III-B)have an abnormal *** work aims to study some of the metabolic and molecular mechanisms underlying MSCs shift from a normal to an abnormal profile in this group of patients.A comparative analysis was undertaken,which included self-renewal capacity,morphology,proliferation capacity,cell cycle,reactive oxygen species(ROS)levels,and senescence-associatedβ‑galactosidase(SA‑β‑gal)staining of BMderived MSCs isolated from 14 BCPs and 9 healthy volunteers(HVs).Additionally,the expression and activity of the telomerase subunit TERT,as well as telomere length,were *** levels of pluripotency,osteogenic,and osteoclastogenic genes(OCT-4,SOX-2,M-CAM,RUNX-2,BMP-2,CCL-2,M-CSF,and IL-6)were also *** results showed that MSCs from BCPs had reduced,self-renewal and proliferation *** cells also exhibited inhibited cell cycle progression and phenotypic changes,such as an enlarged and flattened ***,there was an increase in ROS and senescence levels and a decrease in the functional capacity of TERT to preserve telomere *** also found an increase in pro-inflammatory/pro-osteoclastogenic gene expression and a decrease in pluripotency gene *** conclude that these changes could be responsible for the abnormal functional profile that MSCs show in this group of patients.

关键词： Mesenchymal stem/stromal cells Senescence Breast cancer Bone marrow Pre-metastatic niche Bone metastasis

Helicobacter pylori and oral pathology:Relationship with the gastric infection

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World Journal of Gastroenterology 2014年第29期20卷 9922-9935页

作者： Isabel Adler Andrea Muio Silvia Aguas Laura Harada Mariana Diaz Adriana Lence Mario Labbrozzi Juan Manuel Muio Boris Elsner alejandra Avagnina Valeria Denninghoff Oral Diseases Curriculum School of DentistryUniversity of Buenos AiresC1053ABJ Buenos AiresArgentina Department of Pathology Center for Medical Education and Clinical Research "Norberto Quirno" (CEMIC)1425 Buenos AiresArgentina National Scientific and Technical Research Council (CONICET) Career Member

Helicobacter pylori(***)has been found in the oral cavity and stomach,and its infection is one of the most frequent *** reviewed the literature and conducted a Topic Highlight,which identified studies reporting an association between ***-infection in the oral cavity and ***-positive stomach *** work was designed to determine whether *** is the etiologic agent in periodontal disease,recurrent aphthous stomatitis(RAS),squamous cell carcinoma,burning and *** selection focused on the highest quality studies and *** selected 48 articles reporting on the association between saliva and plaque and *** order to assess periodontal disease data,we included 12 clinical trials and 1 *** evaluated 13 published articles that addressed the potential association with RAS,and 6 with squamous cell *** publications focused on our questions on burning and *** is a close relation between *** infection in the oral cavity and the *** mouth is the first extra-gastric *** the role of *** in the etiology of squamous cell carcinoma,no evidence is still available.

关键词： Helicobacter pylori Oral pathology Gastric infection Burning and halitosis Recurrent aphthous stomatitis

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

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