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Assessing vegetation community distribution characteristics and succession stages in mountainous areas hosting coming Winter Olympics Games

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Journal of Mountain science 2021年第11期18卷 2870-2887页

作者： ZHANG Heng-shuo ZHA Tong-gang YU Yang JI Xiao-dong jesÚs Rodrigo-Comino school of soil and Water Conservation Beijing Forestry UniversityQinghua East Road 35Beijing 100083China Jixian National Forest Ecosystem Research Network station CNERNBeijing Forestry UniversityBeijing 100083China Departamento de Análisis Geográfico Regional y Geografía Física Facultad de Filosofía y LetrasCampus Universitario de CartujaUniversity of Granada18071 GranadaSpain

Alpine mountain ecosystem shows strong interactions between abiotic and biotic *** also receive high attention from human activities(natural tourism,trekking,skiing,etc.).However,as the potential disturbance risk areas in alpine mountains are increasing,it is necessary to understand the relationship between environmental factors and plant *** is also the key consideration for the coming international events such as the Winter Olympic Games,which could generate uncontrolled ecosystem issues not previously *** Yin Mountains in Chongli district,Zhangjiakou City,Hebei Province,China will be the core area of the 2022 Winter Olympic *** hypothesize that disturbances will be caused,therefore,the previous relationships between the habitat factors and plant community and the main environmental limiting factors before hosting them must be assessed to design future restoration ***,we used the two-way indicator species analysis(TWINsPAN)and market basket analysis(MBA)for vegetation classification in 91 sampling *** community and relationships among environmental variables(altitude,slope position,aspect,direction,inclination,soil porosity,soil bulk density,organic matter content and soil pH)were investigated through the trend correspondence(DCA)and canonical correspondence analyses(CCA).Also,the TWINsPAN was used to classify the vegetation into 6 different *** analysis showed that i)the spatial variation of soil moisture and the content of soil organic matter are the main factors limiting the development of shrub and herb communities;ii)the distribution of different forest communities was mainly affected by terrain factors(altitude,aspect and slope position);iii)the dynamic changes of vegetation communities in different altitudes were affected by the fluctuation of environmental factors and human disturbance,and the shrubs and herbaceous plants in mid-to-high altitude areas(above 1400 m)generally show the process o

关键词： Vegetation classification Topographic factors Community distribution Winter Olympic Games

Diagnostic laparoscopy and laparoscopic ultrasonography withlocal anesthesia in hepatocellular carcinoma

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World Journal of Gastroenterology 2005年第26期11卷 4120-4123页

作者： mariano Gómez-Rubio Mercedes Moya-Valdés jesús García Department of Digestive Diseases Getafe University Hospital Getafe MadridSpain

Diagnosis of hepatocellular carcinoma (HCC), a common digestive malignancy, remains a challenge. The aim of this study was to evaluate the feasibility of performing laparoscopy and laparoscopic ultrasound with local anesthesia as a diagnostic procedure in HCC. Laparoscopy and laparoscopic ultrasound with local anesthesia was performed in the gastrointestinal endoscopy unit in three patients diagnosed of HCC. Endoscopy staged diffuse liver disease. Laparoscopic ultrasonography identified all liver tumors not visible during endoscopy and guided needle biopsy in one case. No complications happened. In conclusion, laparoscopy and laparoscopic ultrasound,performed as a minimally invasive diagnostic procedure can be a safe and very promising tool in planning therapy of HCC.

关键词： Laparoscopy Laparoscopic ultrasonography Hepatocellular carcinoma

Novel genetic markers in inflammatory bowel disease

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World Journal of Gastroenterology 2007年第42期13卷 5560-5570页

作者： Lorena Rodríguez-Bores Gabriela C Fonseca marco A Villeda jesús K Yamamoto-Furusho IBD Clinic Department of Gastroenterology Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán Vasco de Quiroga 15 colonia Sección XVI Tlalpan CP 14000 México

Genetic factors play a significant role in determining inflammatory bowel disease(IBD)*** data support genetic contribution to the pathogenesis of IBD,which include familial aggregation,twin studies,racial and ethnic differences in disease *** studies have identified several susceptibility genes contained in different genomic regions named IBD1 to *** oligomerization domain(NOD2)and human leukocyte antigen(HLA)genes are the most extensively studied genetic regions(IBD1 and IBD3 respectively)in *** of the NOD2 gene are associated with Crohn's disease(CD)and several HLA genes are associated with ulcerative colitis(UC)and *** like receptors(TLRs)have an important role in the innate immune response against infections by mediating recognition of pathogen-associated microbial *** single-nucleotide polymorphisms(sNPs)in molecules involved in bacterial recognition seems to be essential to define genetic backgrounds at risk of ***,numerous new genes have been identified to be involved in the genetic susceptibility to IBD:NOD1/Caspase-activation recruitment domains 4(CARD4),Chemokine ligand 20(CCL20),IL-11,and IL-18 among *** characterization of these novel genes potentially will lead to the identification of therapeutic agents and clinical assessment of phenotype and prognosis in patients with IBD.

关键词： Genetic Inflammatory bowel disease Human leukocyte antigen Nucleotide oligomerizationdomain Toll like receptors susceptibility

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

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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

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

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

Renal function and choroidal thickness using swept-source optical coherence tomography in diabetic patients

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International Journal of Ophthalmology(English edition) 2019年第6期12卷 985-989页

作者： Antonio Manuel Garrido-Hermosilla mariola Méndez-Muros Estanislao Gutiérrez-sánchez Cristóbal Morales-Portillo maría jesús Díaz-GrANDa Eduardo Esteban-González Isabel Relimpio-López maría Asunción martínez-Brocca Enrique Rodríguez-de-la-Rúa-Franch Department of Ophthalmology Virgen Macarena University HospitalSeville 41009Spain OftaRed Institute of Health Carlos IIIMadridSpain Department of Endocrinology and Nutrition Virgen Macarena University HospitalSeville 41009Spain

AIM: To assess the relationship between choroidal thickness and renal function in diabetic patients. METHODs: Cross-sectional retrospective clinical study of 42 eyes of 21 ocular treatment-na?ve diabetic patients. Demographic data included: age, sex, type and course of diabetes. Ocular data included: severity of diabetic retinopathy;retinal thickness at the central macular region, as well as choroidal thickness at the central and paracentral quadrants, using automatically generated maps by swept-source optical coherence tomography;presence of cystic macular edema;and ocular axial length(AXL). Lab-test parameters included: glycated hemoglobin(HbA1c), albuminuria, albumin/creatinine ratio in urine, and glomerular filtration rate. REsULTs: A significant negative correlation was mainly observed between several choroidal thicknesses, age(Psignificant positive correlation was found between all choroidal thicknesses, HbA1 c(PsION: Choroidal thickness can represent an additional tool to help clinicians predicting the renal status in ocular treatment-na?ve diabetic patients.

关键词： choroidal thickness renal function swept-source optical coherence tomography spectral-domain optical coherence tomography diabetes mellitus

Flow-Injection Flame Atomic Absorption Determination of Hexavalent Chromium with On-Line Preconcentration on an Anion Imprinted Polymer

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American Journal of Analytical Chemistry 2012年第11期3卷 755-760页

作者： maría Carmen Yebra-Biurrun jesús Manuel Castro-Romero Nieves Carro-marino Department of Analytical Chemistry Nutrition and BromatologyFaculty of ChemistryUniversity of Santiago de CompostelaSantiago de CompostelaSpain Department of Analytical Chemistry Escuela Universitaria PolitécnicaUniversity of A CorunaA CorunaSpain Technological Institute for the Monitoring of the maritime Environment of Galicia(INTECmar) Vilagarcía de ArousaSpain

A flow injection preconcentration system for the flame atomic absorption spectrometric determination of hexavalent chromium has been developed. The method employs on-line preconcentration of Cr(VI) on a minicolumn packed with Cr(VI)-imprinted poly(4-vinyl pyridineco-2-hydroxyethyl methacrylate) placed into a flow injection system. Hexava-lent chromium was eluted with a small volume of diluted hydrochloric acid into the nebulizer-burner system of a flame atomic absorption spectrometer. An enrichment factor of 550 and a 3σ detection limit of 0.04 μg·L-1 along a sampling frequency of 4 h-1 at a sample flow rate of 3.5 mL·min-1. The relative standard deviation is 2.9% for 1 μg·L-1 Cr(VI) (n = 11). The flow injection system proposed has the advantage of being simpler because the use of expensive and sophisticated instruments is avoided. Ease of use, continuous process and selectivity make this method suitable for Cr(VI) determination in different environmental samples such as sea and river waters, soils and sediments.

关键词： Hexavalent Chromium Flame Atomic Absorption spectrometry Preconcentration Flow Injection Environmental samples

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