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Distribution Function of the Blow up Time of the Solution of an Anticipating Random Fatigue Equation

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Acta Mathematica Sinica,English Series 2021年第4期37卷 551-564页

作者： liliana PERALTA Centro de Investigacion en Matematicas UAEHCarretera Pachuca-Tulancingo km 4.5 PachucaHidalgo 42184Mexico

In this paper,we study the distribution function of the time of explosion of a stochastic differential equation modeling the length of the dominant crack due to fatigue.The main novelty is that initial condition is regarded as an anticipating random variable and the stochastic integral is in the forward sense.Under suitable conditions,we use the substitution formula from Russo and Vallois to find the local solution of this equation.Then,we find the law of blow up time by proving some results on barrier crossing probabilities of Brownian bridge.

关键词： Stochastic differential equations random fatigue explosion time forward integral Brownian bridge

Synthesis,characterization and antibacterial activity of copper,nickel and bimetallic Cu–Ni nanoparticles for potential use in dental materials

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Progress in Natural Science:Materials International 2014年第4期24卷 321-328页

作者： liliana Argueta-Figueroa Raúl A.Morales-Luckie Rogelio J.Scougall-Vilchis Oscar F.Olea-mejía School of Medicine Autonomous University State of Mexico (UAEMex)Mexico Department of Materials Science Center for Research in Sustainable Chemistry (CIQS)Autonomous University State of Mexico (UAEMex)Km 14.5Carr.Toluca-AtlacomulcoZC 50200Toluca CityState of MexicoMexico Dental Research Center (CIEAO) Autonomous University State of Mexico (UAEMex)Mexico

The antibacterial effect is a desirable property in dental materials.Development of simple methods for the preparation of nanosized metal particles has attracted significant attention because of their future applications due to unusual size-dependent antibacterial properties.Copper(Cu),Nickel(Ni) and bimetallic Cu–Ni nanoparticles were prepared by a simple chemical method and their antibacterial activity was tested against the widely used standard human pathogens Staphylococcus aureus(gram-negative) and Escherichia coli(gram-positive).Additionally,these nanoparticles were tested against the dental pathogen Streptococcus mutans.Our results are promising for potential use in dental materials science.

关键词： Antibacterial properties Metal nanoparticles Copper nanoparticles Nickel nanoparticles Nano-alloy

Dynamic analysis of a predator-prey model of Gause type with Allee effect and non-Lipschitzian hyperbolic-type functional response

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International Journal of Biomathematics 2024年第1期17卷 81-112页

作者： liliana Puchuri Orestes Bueno Pontificia Universidad Catolica del Peri Av.Universitaria 1801 San MiguelLima 15088Peru Universidad del Pacifico Jr.Gral Luis Sanchez Cerro 2141 Jesus MariaLima 15072Peru

In this work,we study a predator-prey model of Gause type,in which the prey growth rate is subject to an Allee effect and the action of the predator over the prey is determined by a generalized hyperbolic-type functional response,which is neither differentiable nor locally Lipschitz at the predator axis.This kind of functional response is an extension of the so-called square root functional response,used to model systems in which the prey have a strong herd structure.We study the behavior of the solutions in the first quadrant and the existence of limit cycles.We prove that,for a wide choice of parameters,the solutions arrive at the predator axis in finite time.We also characterize the existence of an equilibrium point and,when it exists,we provide necessary and sufficient conditions for it to be a center-type equilibrium.In fact,we show that the set of parameters that yield a center-type equilibrium,is the graph of a function with an open domain.We also prove that any center-type equilibrium is stable and it always possesses a supercritical Hopf bifurcation.In particular,we guarantee the existence of a unique limit cycle,for small perturbations of the system.

关键词： Predator-prey models Gause models Allee effect non-differentiable functional response

Exploring the asymmetric effect of COVID‑19 pandemic news on the cryptocurrency market:evidence from nonlinear autoregressive distributed lag approach and frequency domain causality

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Financial Innovation 2023年第1期9卷 692-749页

作者： Ştefan Cristian Gherghina liliana Nicoleta Simionescu Department of Finance Bucharest University of Economic Studies6 Romana Square010374 BucharestRomania

This paper explores the asymmetric effect of COVID-19 pandemic news,as measured by the coronavirus indices(Panic,Hype,Fake News,Sentiment,Infodemic,and Media Coverage),on the cryptocurrency market.Using daily data from January 2020 to September 2021 and the exponential generalized autoregressive conditional heter-oskedasticity model,the results revealed that both adverse and optimistic news had the same effect on Bitcoin returns,indicating fear of missing out behavior does not prevail.Furthermore,when the nonlinear autoregressive distributed lag model is esti-mated,both positive and negative shocks in pandemic indices promote Bitcoin’s daily changes;thus,Bitcoin is resistant to the SARS-CoV-2 pandemic crisis and may serve as a hedge during market turmoil.The analysis of frequency domain causality supports a unidirectional causality running from the Coronavirus Fake News Index and Sentiment Index to Bitcoin returns,whereas daily fluctuations in the Bitcoin price Granger affect the Coronavirus Panic Index and the Hype Index.These findings may have significant policy implications for investors and governments because they highlight the impor-tance of news during turbulent times.The empirical results indicate that pandemic news could significantly influence Bitcoin’s price.

关键词： COVID-19 Bitcoin NARDL EGARCH Frequency domain causality

Lack of transcriptional coordination between mitochondrial and nuclear oxidative phosphorylation genes in the presence of two divergent mitochondrial genomes

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Zoological Research 2022年第1期43卷 111-128页

作者： Ran Xu Mariangela Iannello Justin CHavird liliana Milani Fabrizio Ghiselli Department of Biological Geological and Environmental SciencesUniversity of BolognaBolognaBO 40126Italy Department of Integrative Biology The University of Texas at AustinAustinTX 78712USA

In most eukaryotes,oxidative phosphorylation(OXPHOS)is the main energy production process and it involves both mitochondrial and nuclear genomes.The close interaction between the two genomes is critical for the coordinated function of the OXPHOS process.Some bivalves show doubly uniparental inheritance(DUI)of mitochondria,where two highly divergent mitochondrial genomes,one inherited through eggs(F-type)and the other through sperm(M-type),coexist in the same individual.However,it remains a puzzle how nuclear OXPHOS genes coordinate with two divergent mitochondrial genomes in DUI species.In this study,we compared transcription,polymorphism,and synonymous codon usage in the mitochondrial and nuclear OXPHOS genes of the DUI species Ruditapes philippinarum using sex-and tissue-specific transcriptomes.Mitochondrial and nuclear OXPHOS genes showed different transcription profiles.Strong co-transcription signal was observed within mitochondrial(separate for F-and M-type)and within nuclear OXPHOS genes but the signal was weak or absent between mitochondrial and nuclear OXPHOS genes,suggesting that the coordination between mitochondrial and nuclear OXPHOS subunits is not achieved transcriptionally.McDonald-Kreitman and frequency-spectrum based tests indicated that M-type OXPHOS genes deviated significantly from neutrality,and that F-type and M-type OXPHOS genes undergo different selection patterns.Codon usage analysis revealed that mutation bias and translational selection were the major factors affecting the codon usage bias in different OXPHOS genes,nevertheless,translational selection in mitochondrial OXPHOS genes appears to be less efficient than nuclear OXPHOS genes.Therefore,we speculate that the coordination between OXPHOS genes may involve post-transcriptional/translational regulation.

关键词： Oxidative phosphorylation Doubly uniparental inheritance Co-transcription Polymorphism Codon usage bias Translational selection

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家政按需服务平台商业计划

家政按需服务平台商业计划

作者： Quintero tirado,Juan Carlos 上海外国语大学

学位级别：硕士

本商业计划将要开发一个为马德里居民提供家政按需服务的平台,在文中将探项目实现的可行性。该平台将连接两个不同环节,即家政服务供应商,和需要这类服务的客户。通过手机或网页应用,客户们可与服务供应商实现实时聊天。同时平台会为服... 详细信息

本商业计划将要开发一个为马德里居民提供家政按需服务的平台,在文中将探项目实现的可行性。该平台将连接两个不同环节,即家政服务供应商,和需要这类服务的客户。通过手机或网页应用,客户们可与服务供应商实现实时聊天。同时平台会为服务供应商提供工具来帮助他们发展业务和经营。所有的交易都将通过应用程序进行。论文中将回答一些重要问题,如潜在的客户数量,客户需求,战略方针等。并遵循逻辑思路,让读者看到一个完整的行业概况、经营中将运用到的不同方法、市场调查等,以及由此制定的市场营销战略,最终将保证此项目获得成功。为了得到这些答案,并对搭建此平台所需的各种概念和框架有一个完整的理解,需要进行详尽的研究,在学术调查部分谈及了所用的研究方法,包括通过采访等手段,了解市场需求,并按客户需要设计此平台。财务计划部分则提供了最佳的公司启动方案,既考虑到了劳动力需求,也考虑到了平台的开发成本和公司启动资金。本项目为长期收益项目,在考虑到了由于市场和用户接受产品后的不同反应而产生的不定变化,展示了该项目的更广阔前景。最后,本文将对那些想要了解按需服务商业的人有所帮助,告诉他们如何通过高科技在全球增长业务,客户的消费习惯如何在改变。同样对于那些想要进军电子商务领域的人也将有参考意义。

关键词：客户需求分享经济平台革新

The power of the public purse: financing of global health partnerships and acienda setting for sustainability

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Chinese Journal of Population,Resources and Environment 2018年第3期16卷 186-196页

作者： liliana B.Andonova Department of International Relations and Political Science Center for International Environmental Studies Graduate Institute of International and Development Studies

Public-private partnerships(PPPs) have reshaped the institutional structure of global governance.They have advanced collaboration on core issues such as health, clean energy, the rights of women and children, and access to infrastructure, among others. But which actors create and finance public-private partnerships in global governance to advance such objectives? What are the implications of the agency behind such collaboration for influencing the global agenda on sustainable development? While some scholars and advocacy groups see the growing role of private actors as a powershift away from public institutions, others argue that such arrangements tend to be complementary to public mandates and indeed may provide a new means for international institutions to pursue such mandates. The article probes this debate by analyzing the type of actors that finance global health partnerships, an area in which the influence of hybrid initiatives is particularly prominent. It reveals that public financing remains a core and necessary condition for the emergence and functioning of PPPs. The growing share of private financing,nonetheless, has important implications for shaping partnerships agendas and steering global health and sustainability governance. Rather than a powershift or abdication of responsibilities by the state, there is rather a tendency of deliberate diffusion of power by donors toward hybrid structures.

关键词： Public-private partnerships power global governance health sustainable development SDGs donor financing public financing global public goods club governance

Mitochondrial selfish elements and the evolution of biological novelties

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Current Zoology 2016年第6期62卷 687-697页

作者： liliana MILANI Fabrizio GHISELLI Marco PASSAMONTI Department of Biological Geological and Environmental Sciences University of Bologna Via Selmi 3 40126Bologna Italy

We report the present knowledge about RPHM21, a novel male-specific mitochondrial protein with a putative role in the paternal inheritance of sperm mitochondria in the Manila clam , a species with doubly uniparental inheritance of mitochondria (DUI). We review all the available data on transcription and translation, analyze in detail its female counterpart, RPHF22, discuss the homology with RPHM21, the putative function and origin, and analyze their polymorphism. The available evidence is compatible with a viral origin of RPHM21 and supports its activity during spermatogenesis. RPHM21 is progressively accumulated in mitochondria and nuclei of spermatogenic cells, and we hypothesize it can influence mitochondrial inheritance and sexual differentiation. We propose a testable model that describes how the acquisition of selfish features by a mitochondrial lineage might have been responsible for the emergence of DUI, and for the evolution of separate sexes (gonochorism) from hermaphroditism. The appearance of DUI most likely entailed the invasion of at least 1 selfish element, and the extant DUI systems can be seen as resolved conflicts. It was proposed that hermaphroditism was the ancestral condition of bivalves, and a correlation between DUI and gonochorism was documented. We hypothesize that DUI might have driven the shift from hermaphroditism to gonochorism, with androdioecy as transition state. The invasion of sex-ratio distorters and the evolution of suppressors can prompt rapid changes among sex-determination mechanisms, and DUI might have been responsible for one of such changes in some bivalve species. If true, DUI would represent the first animal sex-determination system involving mtDNA-encoded proteins.

关键词：线粒体蛋白生物演变元素性别决定机制精子发生过程有限元分析方法两性畸形雌雄异体

A New Approach to State Estimation for Uncertain Linear Systems in a Moving Horizon Estimation Setting

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International Journal of Automation and computing 2016年第6期13卷 653-664页

作者： J.Garcia-tirado H.Botero F.Angulo Faculty of Economic and Administrative Sciences QualityMetrology and Production Research GroupMetropolitan Institute of Technology of Medellin (ITM) KALMAN Research Group Faculty of MinesElectric Energy and Automatics DepartmentNational University of Colombia (MedelliCampus) Perception and Intelligent Control Research Group Department of ElectricalElectronicsand Computational EngineeringFaculty of Engineering and ArchitectureNational University of Colombia (Manizales)Q buildingLa Nubia campus

This paper addresses the state estimation problem for linear systems with additive uncertainties in both the state and output equations using a moving horizon approach. Based on the full information estimation setting and the game-theoretic approach to the H∞filtering, a new optimization-based estimation scheme for uncertain linear systems is proposed, namely the H∞-full information estimator, H∞-FIE in short. In this formulation, the set of processed data grows with time as more measurements are received preventing recursive formulations as in Kalman filtering. To overcome the latter problem, a moving horizon approximation to the H∞-FIE is also presented, the H∞-MHE in short. This moving horizon approximation is achieved since the arrival cost is suitably defined for the proposed scheme. Sufficient conditions for the stability of the H∞-MHE are derived. Simulation results show the benefits of the proposed scheme when compared with two H∞filters and the well-known Kalman filter.

关键词： uncertain processed overcome estimator latter horizon filtering recursive weighting constraints