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Conifer establishment after the eruption of the Paricutin volcano in central Mexico

Forest Ecosystems 2022年第1期9卷 71-82页

作者： jesús Eduardo sáenz-Ceja Blanca Lizeth sáenz-Ceja J.Trinidad sáenz-Reyes Diego Rafael Pérez-salicrup Instituto de Investigaciones en Ecosistemas y sustentabilidad Universidad Nacional Autéonoma de MéxicoAntigua Carretera a Patzcuaro 8701 Col.Ex hacienda San Joséde la Huerta58190MoreliaMexico Escuela Nacional de Estudios superiores Unidad Morelia Universidad Nacional Autónoma de MéxicoAntigua Carretera a Patzcuaro 8701 Col.Ex hacienda San Joséde la Huerta58190MoreliaMexico Instituto Nacional de Investigaciones Forestales Agrícolas y PecuariasCampo Experimental UruapanAv.Latinoamericana 1101Col.Revolución60500UruapanMexico

Background:Volcanic eruptions have large effects on forest ecosystems and create new substrates,triggering primary succession *** Paricutín volcano,born in central-western Mexico,erupted between 1943 and *** the cessation of the eruptive activity,plant colonization began on the lava flows and tephra deposits,including the conifer species that dominate the surrounding mature *** study aims to reconstruct the history of the establishment of conifer trees on the substrates created by the Paricutín ***:16 sampling plots were established along three transects with northern,southern,and south-western aspects,located every 250 m from the preserved forest to the volcanic *** cores from 400 conifer trees were extracted and their age was determined by cross-dating annual tree *** order of the species colonization and the tree establishment,abundance,and dominance patterns were ***,the influence of the distance from the mature forests and the inter-annual climatic conditions on the temporal tree establishment pattern was ***:Eight pine and one fir species have been established since 1970,only 18 years after the end of the eruptive ***,tree establishment increased by 12.9%annually after 1995,with the youngest tree in our sample getting established in *** did not find a well-defined temporal and spatial pattern of species arrival,which suggests that colonization occurred randomly,although the four pine species that were established early became the most abundant and *** establishment was not influenced by the distance from the mature forest,and wet inter-annual conditions did not enhance pulses of tree recruitment,exhibiting a continuous tree establishment ***:Conifer species have shown a great capacity for colonizing volcanic substrates created by the Paricutín eruption,which suggests that tropical montane conifers can regenerate rapidly under high-magni

关键词： Age structure Dendrochronology Lava flow Primary succession Tropical montane forest

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Three-dimensional organ modeling based on deformable surfaces applied to radio-oncology

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Journal of Zhejiang University-science C(Computers and Electronics) 2010年第6期11卷 407-417页

作者： Gloria BUENO Oscar DéNIZ jesús sALIDO Carmen CARRAsCOsA José M. DELGADO Grupo de Visióny sistemas Inteligentes Universidad de Castilla-La Mancha E.T.S. Ingenieros Industriales Avda. Camilo José Cela 3. 13071 Ciudad Real Spain Hospital General de Ciudad Real Tomelloso s/n. 13005 Ciudad Real Spain Instituto Oncológico (Grupo IMO) Modesto Lafuente 14 28010 Madrid Spain

This paper describes a method based on an energy minimizing deformable model applied to the 3D biomechanical modeling of a set of organs considered as regions of interest (ROI) for radiotherapy. The initial model consists of a quadratic surface that is deformed to the exact contour of the ROI by means of the physical properties of a mass-spring system. The exact contour of each ROI is first obtained using a geodesic active contour model. The ROI is then parameterized by the vibration modes resulting from the deformation process. Once each structure has been defined, the method provides a 3D global model including the whole set of ROIs. This model allows one to describe statistically the most significant variations among its structures. statistical ROI variations among a set of patients or through time can be analyzed. Experimental results are presented using the pelvic zone to simulate anatomical variations among structures and its application in radiotherapy treatment planning.

关键词： 3D biomechanical organ modeling Energy minimizing deformable model Finite element model Geodesic active contour Radiotherapy treatment planning

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somatic second-hit mutations leads to polycystic liver diseases

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World Journal of Gastroenterology 2013年第1期19卷 141-143页

作者： jesús M Banales Patricia Munoz-Garrido Luis Bujanda Division of Hepatology and Gastroenterology Donostia Universitary HospitalBiodonostia Research InstituteE-20014 San SebastiánSpain Department of Liver and Gastrointestinal Diseases National Institute for the Study of Liver and Gastrointestinal Diseases(CIBERehdfunded by the Spanish Carlos III Institute)08036 BarcelonaSpain Ikerbasque Basque Foundation for Science48011 BilbaoSpain spanish Association Against Cancer(AECC) 28040 MadridSpain

Polycystic liver diseases(PCLDs) are a heterogeneous group of genetic disorders characterized by the development of multiple fluid-filled cysts in the liver,which derive from cholangiocytes,the epithelial cells lining the bile *** these cysts grow,symptoms such as abdominal distension,nausea,and abdominal pain may *** may exist isolated(i.e.,autosomal dominant polycystic liver disease,ADPLD) or in combination with renal cystogenesis(i.e.,autosomal dominant polycystic kidney disease and autosomal recessive polycystic liver disease).The exact prevalence of PCLDs is unknown,but is estimated to occur in approximately 1:1000 *** the pathogenesis of each form of PCLD appears to be different,increasing evidences indicate that hepatic cystogenesis is a phenomenon that may involve somatic loss of heterozygosity(LOH) in those pathological conditions inherited in a dominant form.A recent report,using highly sophisticated methodology,demonstrated that ADPLD patients with a germline mutation in the protein kinase C substrate 80K-H(PRKCsH) gene mostly develop hepatic cystogenesis through a second somatic *** hepatocystin,the PRKCsH-encoding protein,was absent in the hepatic cysts with LOH,it was still expressed in the heterozygous *** the other hand,no additional trans-heterozygous mutations on the sEC63 homolog(*** /sEC63) gene(also involved in the development of PCLDs) were *** data indicate that PCLD is recessive at the cellular level,and point out the important role of hepatocystin loss in *** this commentary,we discuss the knowledge regarding the role of somatic second-hit mutations in the development of PCLDs,and the most relevant findings have been highlighted.

关键词： Polycystic liver diseases Cholangiocyte Cystogenesis Loss of heterozygosity Protein kinase C substrate 80K-H sEC63

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Cholangiocyte anion exchange and biliary bicarbonate excretion

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World Journal of Gastroenterology 2006年第22期12卷 3496-3511页

作者： jesús M Banales jesús Prieto Juan F Medina Laboratory of Molecular Genetics Division of Gene Therapy and Hepatology University of Navarra School of MedicineClinica Universitaria and CIMAPamplonaSpain

Primary canalicular bile undergoes a process of fluidization and alkalinization along the biliary tract that is influenced by several factors including hormones, innervation/neuropeptides, and biliary constituents. The excretion of bicarbonate at both the canaliculi and the bile ducts is an important contributor to the generation of the so-called bile-salt independent flow. Bicarbonate is secreted from hepatocytes and cholangiocytes through parallel mechanisms which involve chloride efflux through activation of Cl- channels, and further bicarbonate secretion via AE2/sLC4A2-mediated Cl-/HCO3- exchange. Glucagon and secretin are two relevant hormones which seem to act very similarly in their target cells （hepatocytes for the former and cholangiocytes for the latter）. These hormones interact with their specific G protein-coupled receptors, causing increases in intracellular levels of cAMP and activation of cAMP-dependent Cl- and HCO3- secretory mechanisms. Both hepatocytes and cholangiocytes appear to have cAMP-responsive intracellular vesicles in which AE2/sLC4A2 colocalizes with cell specific Cl- channels （CFTR in cholangiocytes and not yet determined in hepatocytes） and aquaporins （AQP8 in hepatocytes and AQP1 in cholangiocytes）, cAMP-induced coordinated trafficking of these vesicles to either canalicular or cholangiocyte lumenal membranes and further exocytosis results in increased osmotic forces and passive movement of water with net bicarbonate-rich hydrocholeresis.

关键词： AE2 anion exchanger Bile salt-independent flow Biliary bicarbonate excretion Regulation of intracellular pH Hydroionic fluxes in cholangiocytes

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A comprehensive investigation on nonlinear vibration and bending characteristics of bio-inspired helicoidal laminated composite structures

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 81-100页

作者： s.sAURABH R.KIRAN D.sINGH R.VAIsH V.s.CHAUHAN school of Mechanical and Materials Engineering Indian Institute of Technology Mandi

Bio-inspired helicoidal composite laminates, inspired by the intricate helical structures found in nature, present a promising frontier for enhancing the mechanical properties of structural designs. Hence, this study provides a comprehensive investigation into the nonlinear free vibration and nonlinear bending behavior of bio-inspired composite plates. The inverse hyperbolic shear deformation theory(IHsDT) of plates is employed to characterize the displacement field, with the incorporation of Green-Lagrange nonlinearity. The problem is modeled using the C0finite element method(FEM), and an in-house code is developed in the MATLAB environment to solve it numerically. Various helicoidal layup configurations including helicoidal recursive(HR), helicoidal exponential(HE), helicoidal semi-circular(Hs), linear helicoidal(LH), and Fibonacci helicoidal(FH)with different layup sequences and quasi-isotropic configurations are studied. The model is validated, and parametric studies are conducted. These studies investigate the effects of layup configurations, side-to-thickness ratio, modulus ratios, boundary conditions, and loading conditions at different load amplitudes on the nonlinear vibration and nonlinear bending behaviors of bio-inspired composite plates. The results show that the laminate sequence exerts a substantial impact on both nonlinear natural frequencies and nonlinear bending behaviors. Moreover, this influence varies across different side-to-thickness ratios and boundary conditions of the bio-inspired composite plate.

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semantic segmentation of Lumbar Vertebrae Using Meijering U-Net(MU-Net)on spine Magnetic Resonance Images

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Computer Modeling in Engineering & sciences 2025年第1期142卷 733-757页

作者： Lakshmi s V V shiloah Elizabeth Darmanayagam sunil Retmin Raj Cyril Department of Computer science and Engineering College of Engineering GuindyAnna UniversityChennai600025India Department of Information Technology Madras Institute of TechnologyAnna UniversityChrompetChennai600044India

Lower back pain is one of the most common medical problems in the world and it is experienced by a huge percentage of people *** to its ability to produce a detailed view of the soft tissues,including the spinal cord,nerves,intervertebral discs,and vertebrae,Magnetic Resonance Imaging is thought to be the most effective method for imaging the *** semantic segmentation of vertebrae plays a major role in the diagnostic process of lumbar *** is difficult to semantically partition the vertebrae in Magnetic Resonance Images from the surrounding variety of tissues,including muscles,ligaments,and intervertebral discs.U-Net is a powerful deep-learning architecture to handle the challenges of medical image analysis tasks and achieves high segmentation *** work proposes a modified U-Net architecture namely MU-Net,consisting of the Meijering convolutional layer that incorporates the Meijering filter to perform the semantic segmentation of lumbar vertebrae L1 to L5 and sacral vertebra ***-colour mask images were generated and used as ground truth for training the *** work has been carried out on 1312 images expanded from T1-weighted mid-sagittal MRI images of 515 patients in the Lumbar spine MRI Dataset publicly available from Mendeley *** proposed MU-Net model for the semantic segmentation of the lumbar vertebrae gives better performance with 98.79%of pixel accuracy(PA),98.66%of dice similarity coefficient(DsC),97.36%of Jaccard coefficient,and 92.55%mean Intersection over Union(mean IoU)metrics using the mentioned dataset.

关键词： Computer aided diagnosis(CAD) magnetic resonance imaging(MRI) semantic segmentation lumbar vertebrae deep learning U-Net model

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Engineering the smart Factory

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Chinese Journal of Mechanical Engineering 2016年第6期29卷 1046-1051页

作者： HARRIsON Robert vera Daniel AHMAD Bilal Warwick Manufacturing Group University of Warwick

The fourth industrial revolution promises to create what has been called the smart factory. The vision is that within such modular structured smart factories, cyber-physical systems monitor physical processes, create a virtual copy of the physical world and make decentralised decisions. This paper provides a view of this initiative from an automation systems perspective. In this context it considers how future automation systems might be effectively configured and supported through their lifecycles and how integration, application modelling, visualisation and reuse of such systems might be best achieved. The paper briefly describes limitations in current engineering methods, and new emerging approaches including the cyber physical systems （CPs） engineering tools being developed by the automation systems group （AsG） at Warwick Manufacturing Group, University of Warwick, UK.

关键词： index terms--smart factory Industry 4.0 automation systems cyber-physical systems engineering lifecycle

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Khettaras in the Taflalet oasis(Morocco):contribution to the promotion of tourism and sustainable development

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Built Heritage 2022年第4期6卷 35-50页

作者： Mohamed Beraaouz Mohamed Abioui Mohammed Hssaisoune jesús Martínez‑Frías Laboratory of Applied Geology and Geo‑Environment Department of Erath SciencesFaculty of SciencesIbn Zohr UniversityAgadirMorocco. Monachus Group of scientifc Research and Ecological Education ConstantaRomania. Faculty of Applied sciences Ibn Zohr UniversityAit MelloulMorocco. Insti‑tuto de Geociencias CSIC-Universidad Complutense de MadridMadridSpain.

The khettaras constitute a hydraulic system for mobilising water by gravity from the water table to the surface to irrigate felds in *** system,which has been fairly widespread in North Africa,in particular in Algeria(foggara)and Morocco(khettaras),was introduced several centuries ago in the oases of southeastern Morocco and has contin‑ued to operate despite various natural and anthropic *** on these ingenious and millennial hydraulic systems,successive civilisations living in these environments have been able to establish laws and regulations for the management and mobilisation of natural resources,especially ***,to get the most out of these systems,users have had to abide by rules(Al Orf/Azref)designed to protect,promote,and care for the systems to enhance their *** hydraulic systems have declined in recent years,notably due to extensive groundwater pumping,climate variability(severe droughts),and the local population’s disinterest for this type of ***,we have unfortunately witnessed the loss of a thousand-year-old local ancestral know-how that had been developed by diferent succeeding civilisations in the *** initiatives(2008–2011)have been undertaken by the Moroccan government for the restoration and development of some abandoned khettaras in the Taflalet Oasis so that they could be utilised in the development of an oasis-based cultural tourism and integrated in a tourist circuit known as *** initiative,still in its infancy,has constituted an alternative and a fairly encouraging development for this national and world heritage.

关键词： Taflalet oasis Interactions society-environment Integrated water management Water civilisation

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Predicting Maximum Lifespan Limits at Mean Menopausal Age

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Journal of Mathematical Research with Applications 2025年第1期 133-142页

作者： M.sUMATHI s.ANTONY CARLA Department of Mathematics N.M.S.S.Vellaichamy Nadar College Research scholar (Part-time) Madurai Kamaraj University

The age at which a woman enters natural menopause has also been associated to death from any cause. Menopause is a natural component of aging that happens between the ages of 45 and 55, with the average menopausal age being 51. Previous research has revealed the age at which women reach menopause, but there is no evidence to support the link between menopause and longevity. We made a study in assessing the limits of maximum lifespan at menopausal age in our previous article. In this paper, we aim to predict the maximum lifespan of women at mean menopausal age.

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software Vulnerabilities Overview:A Descriptive study

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Tsinghua science and Technology 2020年第2期25卷 270-280页

作者： Mario Calín sánchez Juan Manuel Carrillo de Gea José Luis Fernández-Alemán jesús Garcerán Ambrosio Toval the Department of Informatics and systems Faculty of Computer ScienceUniversity of Murcia

Computer security is a matter of great *** the last decade there have been numerous cases of cybercrime based on the exploitation of software *** fact has generated a great social concern and a greater importance of computer security as a *** this work,the most important vulnerabilities of recent years are identified,classified,and categorized individually.A measure of the impact of each vulnerability is used to carry out this classification,considering the number of products affected by each vulnerability,as well as its *** addition,the categories of vulnerabilities that have the greatest presence are *** on the results obtained in this study,we can understand the consequences of the most common vulnerabilities,which software products are affected,how to counteract these vulnerabilities,and what their current trend is.

关键词： descriptive study software security software vulnerabilities vulnerability databases

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