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Existence and Uniqueness of Fixed Point in Partially Ordered sets and Applications to Ordinary Differential Equations

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Acta Mathematica sinica,English series 2007年第12期23卷 2205-2212页

作者： Juan J.nieto RosanaRODRGUEZ-LPEZ Departamento de Análisis Matemático Facultad de MatemáticasUniversidad de Santiago de Compostela

We prove some fixed point theorems in partially ordered sets, providing an extension of the Banach contractive mapping theorem. Having studied previously the nondecreasing case, we consider in this paper nonincreasing mappings as well as non monotone mappings. We also present some applications to first-order ordinary differential equations with periodic boundary conditions, proving the existence of a unique solution admitting the existence of a lower solution.

关键词： fixed point partially ordered set first-order differential equation lower and upper solutions

The flowerpiercers interactions with a community of high Andean plants

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Avian Research 2021年第2期12卷 181-194页

作者： Jairo andrés Cuta-Pineda Luis Alejandro Arias-sosa Roxibell C.Pelayo Research Group“Grupo Ecología de Organismos(GEO-UPTC)” TunjaColom-bia Maestría en Ciencia Biológicas Universidad Pedagógica y Tecnológica de ColombiaTunjaColombia Instituto de Ciencias Ambientales y Ecológicas(ICAE) Universidad de Los AndesMéridaVenezuela

Background:Flowerpiercers(Diglossa)are traditionally considered as“parasites”of the pollination processes,as they can access the nectar without entering in contact with the reproductive structures of the ***,the effect of flowerpiercers seems to vary according to their behavior and the flower’s ***,in this work,we aimed to explore the floral characteristics that may determine the susceptibility to robbing and pollen transport by ***,we identified the potential types of interactions and studied interaction network ***:We collected the information of 16 ornithophilic plants regarding their floral traits and robbing ***,we captured 4 species of flowerpiercers and evaluated pollen transport(frequency and loads).We tested the correlation between floral traits,robbing frequency,and pollen ***,we used these variables in a cluster and principal component analyses to identify the potential types of ***,we analyzed and com-pared the structure of the plants-flowerpiercers interaction ***:Nectar production significantly influenced both nectar robbing and pollen *** the corolla length was only correlated to the robbing ***,we found that particular flowerpiercers species trans-ported higher loads of some plant pollen,which can be related to the differences in behavior and morphometric *** proposed the classification of five different types of plant-flowerpiercer interactions,that showed differ-ent potential mutualist or antagonist relations based on the affectation of nectar robbing and the service of pollen *** interaction networks consisted of 49 links,with 2.4 links per species,and presented indicators of a medium to high resilience,stability,and resistance(nestedness,connectance,and robustness).Also,the network presented medium to low specialization and substantial niche ***:The ecological role of

关键词： Diglossa Flower traits Nectar robbing Nectivorous birds Pollen transport Pollination

ARTICLE REFLECTIONs ON EU INTERNATIONAL TRADE LAW： AN INTROsPECTIVE VIEW

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Frontiers of Law in China-selected Publications from Chinese Universities 2012年第1期7卷 1-20页

作者： Rafael leal-A rcas Queen Mary University of London United Kingdom

This article presents three main arguments： First, shared competence exists between the national and supranational levels within the European Union （EU） because EU Member states do not trust the European Commission in the external relations law of the EU. second, the EU will have greater bargaining power in international negotiations if it speaks in a single voice. Within the EU-27, we have compatible values, overlapping interests, shared goals, as well as economic, social and political ties. Therefore, there is a presumption of collective action in the EU＇s external relations. However, EU Member states disagree on many issues before they start negotiations, while trying to define a mission together as partners of the European project. Third, Member states confer specific negotiating powers on the EU only when it is in their own national interest to have a common European position on international negotiations.

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EXIsTENCE AND UNIQUENEss OF sOLUTIONs FOR NONLINEAR FRACTIONAL DIFFERENTIAL EQUATIONs WITH NON-sEPARATED TYPE INTEGRAL BOUNDARY CONDITIONs

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Acta Mathematica scientia 2011年第6期31卷 2122-2130页

作者： Bashir Ahmad Juan J. nieto Ahmed Alsaedi Department of Mathematics Faculty of ScienceKing Abdulaziz University Departamento de Anlisis Matemtico Facultad de MatemticasUniversidad de Santiago de Compostela

In this paper, we study a boundary value problem of nonlinear fractional dif- ferential equations of order q （1 〈 q 〈 2） with non-separated integral boundary conditions. some new existence and uniqueness results are obtained by using some standard fixed point theorems and Leray-schauder degree theory. some illustrative examples are also presented. We extend previous results even in the integer case q = 2.

关键词： fractional differential equations non-separated integral boundary conditions contraction principle Krasnoselskii's fixed point theorem Lerayschauder degree

Brain-derived neurotrophic factor signaling in the neuromuscular junction during developmental axonal competition and synapse elimination

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Neural Regeneration Research 2025年第2期20卷 394-401页

作者： Josep Tomàs Víctor Cilleros-Mañé Laia Just-Borràs Marta Balanyà-segura Aleksandra Polishchuk Laura Nadal Marta Tomàs Carolina silvera-simón Manel M.santafé Maria A.Lanuza Unitat d’Histologia i Neurobiologia(UHNeurob) Facultat de Medicina i Ciències de la SalutUniversitat Rovira i VirgiliReusSpain

During the development of the nervous system,there is an overproduction of neurons and *** competition between neighboring nerve endings and synapses performing different activity levels leads to their elimination or *** have extensively studied the involvement of the brain-derived neurotrophic factor-Tropomyosin-related kinase B receptor neurotrophic retrograde pathway,at the neuromuscular junction,in the axonal development and synapse elimination process versus the synapse *** purpose of this review is to describe the neurotrophic influence on developmental synapse elimination,in relation to other molecular pathways that we and others have found to regulate this *** particular,we summarize our published results based on transmitter release analysis and axonal counts to show the different involvement of the presynaptic acetylcholine muscarinic autoreceptors,coupled to downstream serine-threonine protein kinases A and C(PKA and PKC)and voltage-gated calcium channels,at different nerve endings in developmental *** dynamic changes that occur simultaneously in several nerve terminals and synapses converge across a postsynaptic site,influence each other,and require careful studies to individualize the mechanisms of specific *** describe an activity-dependent balance(related to the extent of transmitter release)between the presynaptic muscarinic subtypes and the neurotrophin-mediated TrkB/p75NTR pathways that can influence the timing and fate of the competitive interactions between the different axon *** downstream displacement of the PKA/PKC activity ratio to lower values,both in competing nerve terminals and at postsynaptic sites,plays a relevant role in controlling the elimination of supernumerary ***,calcium entry through L-and P/Q-subtypes of voltage-gated calcium channels(both channels are present,together with the N-type channel in developing nerve terminals)contributes to red

关键词： acetylcholine release adenosine receptors axonal competition brain-derived neurotrophic factor calcium channels motor end-plate muscarinic acetylcholine receptors postnatal synapse elimination serine kinases tropomyosin-related kinase receptorB

Dimensions of hepatocellular carcinoma phenotypic diversity

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World Journal of Gastroenterology 2018年第40期24卷 4536-4547页

作者： Romain Désert Natalia nieto Orlando Musso Institut NuMeCan Université de Rennes 1 Institut national de la recherche agronomique (INRA) Institut national de la santé et de la recherche médicale (INSERM) Department of Pathology Department of Medicine (Gastroenterology and Hepatology) University of Illinois at Chicago

Hepatocellular carcinoma(HCC) is the 3^(rd) leading cause of cancer-related death worldwide. More than 80% of HCCs arise within chronic liver disease resulting from viral hepatitis, alcohol, hemochromatosis, obesity and metabolic syndrome or genotoxins. Projections based on Western lifestyle and its metabolic consequences anticipate a further increase in incidence, despite recent breakthroughs in the management of viral hepatitis. HCCs display high heterogeneity of molecular phenotypes, which challenges clinical management. However, emerging molecular classifications of HCCs have not yet formed a unified corpus translatable to the clinical practice. Thus, patient management is currently based upon tumor number, size, vascular invasion, performance status and functional liver reserve. Nonetheless, an impressive body of molecular evidence emerged within the last 20 years and is becoming increasingly available to medical practitioners and researchers in the form of repositories. Therefore, the aim this work is to review molecular data underlying HCC classifications and to organize this corpus into the major dimensions explaining HCC phenotypic diversity. Major efforts have been recently made worldwide toward a unifying "clinically-friendly" molecular landscape. As a result, a consensus emerges on three major dimensions explaining the HCC heterogeneity. In the first dimension, tumor cell proliferation and differentiation enabled allocation of HCCs to two major classes presenting profoundly different clinical aggressiveness. In the second dimension, HCC microenvironment and tumor immunity underlie recent therapeutic breakthroughs prolonging patients' survival. In the third dimension,metabolic reprogramming, with the recent emergence of subclass-specific metabolic profiles, may lead to adaptive and combined therapeutic approaches. Therefore, here we review recent molecular evidence, their impact on tumor histopathological features and clinical behavior and highlight the r

关键词： Liver metabolism Liver zonation Hepatocellular carcinoma classification Wnt/β-catenin TP53 Tumor microenvironment Inflammation Tumor immunity Hepatocyte proliferation Hepatocyte differentiation

Women in visual neural regeneration research

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Neural Regeneration Research 2025年第2期20卷 489-490页

作者： Tonia s.Rex David J.Calkins Vanderbilt Eye Institute Vanderbilt University Medical CenterNashvilleTNUSA

The year 2024 marks the 60^(th)anniversary of Title IX and 25 years since the New York Times revealed bias against female faculty members at the Massachusetts Institute of *** take an opportunity here to examine the state of gender bias in a relatively new yet already prominent field,neural regeneration in the visual system,for which there is a well-defined context useful for this *** National Eye Institute(NEI)provided the first round of research funding for its Audacious Goals Initiative(AGI)on visual neural regeneration in 2013 and the last round in ***,we focus on this *** sources included PubMed,the National science Foundation(NsF),the NEI,the Blue Ridge Institute for Medical Research and data from the major professional organization for eye and vision research,the Association for Research in Vision and Ophthalmology(ARVO).

关键词： neural visual Times

Automatic Liver Tumor segmentation in CT Modalities Using MAT-ACM

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Computer systems science & Engineering 2022年第12期43卷 1057-1068页

作者： s.Priyadarsini Carlos andrés Tavera Romero Abolfazl Mehbodniya P.Vidya sagar sudhakar sengan Department of Computer science and Engineering P.S.R.Engineering CollegeSivakasiTamil Nadu626123India COMBA R&D Laboratory Faculty of EngineeringUniversidad Santiago de CaliCali76001Colombia Department of Electronics and Communications Engineering Kuwait College of Science and TechnologyKuwait Department of Computer science and Engineering Koneru Lakshmaiah Education FoundationVaddeswaramAndhra Pradesh522502India Department of Computer science and Engineering PSN College of Engineering and TechnologyTirunelveliTamil Nadu627152India

In the recent days, the segmentation of Liver Tumor (LT) has beendemanding and challenging. The process of segmenting the liver and accuratelyspotting the tumor is demanding due to the diversity of shape, texture, and intensity of the liver image. The intensity similarities of the neighboring organs of theliver create difficulties during liver segmentation. The manual segmentation doesnot provide an accurate segmentation because the results provided by differentmedical experts can vary. Also, this manual technique requires a large numberof image slices and time for segmentation. To solve these issues, the Fully Automatic segmentation (FAs) technique is proposed. In this proposed Multi-AngleTexture Active Contour Model (MAT-ACM) method, the input Computed Tomography (CT) image is preprocessed by Contrast Enhancement (CE) with Non-Linear Mapping Technique (NLMT), in which the liver is differentiated from itsneighbouring soft tissues with related strength. Then, the filtered images are givenas the input to Adaptive Edge Modeling (AEM) with Canny Edge Detection(CED) technique, which segments the Liver Region (LR) from the given CTimages. An AEM with a CED model is implemented, which increases the convergence speed of the iterative process for decreasing the Volumetric Overlap Error(VOE) is 6.92% rates when compared with the traditional segmentation Techniques (sT). Finally, the Liver Tumor segmentation (LTs) is developed by applyingthe MAT-ACM, which accurately segments the LR from the segmented LRs. Theevaluation of the proposed method is compared with the existing LTs methodsusing various performance measures to prove the superiority of the proposedMAT-ACM method.

关键词： Computed tomography contrast enhancement adaptive edge modeling multi-angle texture active contour liver tumor segmentation

Unlocking hypoglycemia–associated brain microvascular dysfunction:critical insights from proteomic analysis

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Neural Regeneration Research 2025年第6期20卷 1707-1708页

作者： siva s.V.P.sakamuri Anil sakamuri Department of Chemistry Auburn University at MontgomeryMontgomeryALUSA Vascular Biology Center and Department of Medicine Medical College of Georgia at Augusta UniversityAugustaGAUSA

Hypoglycemia-a critical complication linked to worsened brain function in diabetic subjects:Hypoglycemia is characterized by a decline in circulatory glucose levels below sta nda rd physiological *** hypoglycemia,classified as level 1 hypoglycemia,is defined by blood glucose levels below 70 mg/dL and can be effectively addressed through carbohydrate *** hypoglycemia,denoted by blood glucose levels less than 54 mg/dL,poses a life-threatening risk if left *** with type 1 and type 2 diabetes undergoing insulin treatment are particularly susceptible to hypoglycemia due to impaired counterregulatory mechanisms.

关键词： impaired intake critical