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Decreasing nutrient concentrations in soils and trees with increasing elevation across a treelineecotone in Rolwaling Himal, Nepal

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Journal of Mountain Science 2017年第5期14卷 843-858页

作者： Simon DROLLINGER Michael MULLER Timo KOBL niels SCHWAB Jurgen BOHNER Udo SCHICKHOFF Thomas SCHOLTEN Geoecology Department of Geography and Regional Research University of Vienna Vienna Austria Soil Science and Geomorphology Department of Geosciences Uniuersity of Tubingen Tubingen Germany CEN Center for Earth System Research and Sustainability Institute of Geography University of Hamburg Hamburg Germany

At a global scale, tree growth in alpine treeline ecotones is limited by low temperatures. At a local scale, however, tree growth at its upper limit depends on multiple interactions of influencing factors and mechanisms. The aim of our research was to understand local scale effects of soil properties and nutrient cycling on tree growth limitation, and their interactions with other abiotic and biotic factors in a near-natural Himalayan treeline ecotone. Soil samples of different soil horizons, litter, decomposition layers, and foliage samples of standing biomass were collected in four altitudinal zones along three slopes, and were analysed for exchangeable cations and nutrient concentrations, respectively. Additionally, soil and air temperature, soil moisture, precipitation, and tree physiognomy patterns were evaluated. Both soil nutrients and foliar macronutrient concentrations of nitrogen(N), magnesium(Mg), potassium(K), and foliar phosphorus(P) decrease significantly with elevation. Foliar manganese(Mn) concentrations, bycontrast, are extraordinarily high at high elevation sites. Potential constraining factors on tree growth were identified using multivariate statistical approaches. We propose that tree growth, treeline position and vegetation composition are affected by nutrient limitation, which in turn, is governed by low soil temperatures and influenced by soil moisture conditions.

关键词： Foliar nutrients Himalaya Nitrogen Nutrient cycling Podzol Treeline

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A wood-wood joining system suitable for digital fabrication and its application in the design of a“wood-only”spatial modulea

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Frontiers of Architectural Research 2023年第3期12卷 523-540页

作者： Antonio jesús de-los-Aires-Solís Francisco Gonzalez-Quintial Doctoral School.University of the Basque Country UPV/EHULeioa 48940Spain Department of Architecture.University of the Basque Country UPV/EHULeioa 48940Spain

This paper describes a wood-wood spatial joining system adapted to digital fabrication which has been designated the“Spatial Masterkey”.The wood stereotomy of the joints between the different pieces that make up this joining system is inspired by a three-dimensional puzzle called“snowflake”.The production process used in the masterkey system can be carried out using only a 3-axis CNC milling machine—a relatively affordable and easily accessible *** using digital manufacturing for the execution of wood-wood joints,several benefits are obtained including faster machining and greater cutting precision and uniformity in the products *** advantages make this joining system both economically competitive and environmentally ***,the versatility of this joining system means that its configuration can be adapted to a wide range of casuistry of encounters between members,which means that it can be used for a number of spatial *** includes,but is not limited to,the spatial module presented in this document.

关键词： Wood-wood joinery Digital fabrication 3-Axis CNC Spatial module Sustainability Burr puzzle

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Numerical modeling of nutrient transport to assess the agricultural impact on the trophic state of reservoirs

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International Soil and Water Conservation Research 2023年第1期11卷 197-212页

作者： Franklin Torres-Bejarano jesús García-Gallego Javier Salcedo-Salgado Department of Environmental Engineering University of CordobaCarrera 6 No.77-305230002MonteriaColombia Environmental Engineering Program University of CordobaCarrera 6 No.77-305230002MonteriaColombia

A trophic state increase relates to surface water bodies nutrient enrichment,due to the chemical products used such as fertilizers in agriculture and residues from cattle raising *** research consists of nutrient transport numerical modeling to analyze the Betancíreservoir trophic state in Colombia;Water samples were collected to analyze total nitrogen,total phosphorus,ammonia,nitrates,nitrites,phosphates,chlorophyll-a,dissolved oxygen,BOD,COD,suspended solids,and water *** water quality model MOHID Studio was implemented and after its calibration,scenarios of increase and decrease of nutrients and inflows to the reservoir through its main tributaries were simulated to reproduce the agricultural activity changes in the basin and the effects that would have on the reservoir's trophic state dynamics;Therefore,the Carlson Trophic Status Index was calculated for each *** results show that variations in total nitrogen concentration and increased inflows present short-term consequences on the reservoir's trophic *** the incoming total nitrogen con-centrations by 100%causes the reservoir to change from a light eutrophic to a hypereutrophic *** results of this research provide a starting tool to water resources integrated management in reservoirs.

关键词： Environmental modeling Trophic state index Nutrient transport Eutrophication Water pollution

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Rheumatic manifestations of inflammatory bowel disease

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World Journal of Gastroenterology 2009年第44期15卷 5517-5524页

作者： Tatiana Sofía Rodríguez-Reyna Cynthia Martínez-Reyes jesús Kazúo Yamamoto-Furusho Department of Immunology and Rheumatology National Institute of Medical Sciences and Nutrition Salvador ZubiránVasco de Quiroga 15Col Sección XVI. DelTlalpanMexico City 14000Mexico Department of Gastro-enterology National Institute of Medical Sciences and Nutrition Salvador ZubiránVasco de Quiroga 15Col Sección XVI. DelTlalpanMexico City 14000Mexico

This article reviews the literature concerning rheu-matic manifestations of inflammatory bowel disease (IBD),including common immune-mediated pathways,frequency,clinical course and therapy. Musculoskel-etal complications are frequent and well-recognized manifestations in IBD,and affect up to 33% of pa-tients with IBD. The strong link between the bowel and the osteo-articular system is suggested by many clinical and experimental observations,notably in HLA-B27 transgenic rats. The autoimmune pathogenic mechanisms shared by IBD and spondyloarthropathies include genetic susceptibility to abnormal antigen pre-sentation,aberrant recognition of self,the presence of autoantibodies against specific antigens shared by the colon and other extra-colonic tissues,and increased intestinal permeability. The response against microor-ganisms may have an important role through molecular mimicry and other mechanisms. Rheumatic mani-festations of IBD have been divided into peripheral arthritis,and axial involvement,including sacroiliitis,with or without spondylitis,similar to idiopathic anky-losing spondylitis. Other periarticular features can oc-cur,including enthesopathy,tendonitis,clubbing,peri-ostitis,and granulomatous lesions of joints and *** and osteomalacia secondary to IBD and iatrogenic complications can also occur. The manage-ment of the rheumatic manifestations of IBD consists of physical therapy in combination with local injection of corticosteroids and nonsteroidal anti-inflammatory drugs; caution is in order however,because of their possible harmful effects on intestinal integrity,perme-ability,and even on gut inflammation. Sulfasalazine,methotrexate,azathioprine,cyclosporine and lefluno-mide should be used for selected indications. In some cases,tumor necrosis factor-α blocking agents should be considered as first-line therapy.

关键词： Inflammatory bowel disease Spondylitis Rheumatic diseases

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Spatial distribution of morphometric parameters of glacial cirques in the Central Pyrenees(Aran and Boí valleys)

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Journal of Mountain Science 2018年第10期15卷 2103-2119页

作者： Luis LOPES Marc OLIVA Marcelo FERNANDES Paulo PEREIRA Pedro PALMA jesús RUIZ-FERNáNDEZ Centre for Geographical Studies – IGOT Universidade de Lisboa Department of Geography University of Barcelona Environmental Management Center Mykolas Romeris University Department of Geography University of Oviedo

Glacial cirques are typical landscape features of mid-latitude mountain environments like the Central Pyrenees. Their morphology as well as their spatial distribution provides insights about past glaciers and climates. In this study, we examine the distribution, morphometrical and topographical characteristics of glacial cirques in two U-shaped glacial valleys located in the Central Pyrenees – the Aran and the Boí valleys. They are located in different aspects of this mountain range(north vs south) under different climatic influences that promoted distinct glaciation patterns during the late Pleistocene. The spatial mapping of these landforms was carried out using high-resolution imagery and field observations. We analysed the data of the morphometrical and topographical variables of the glacial cirques by using different statistical and geospatial methods in order tounveil the factors controlling their formation and development. A total of 186 glacial cirques were mapped in the study area, including 119 in the Aran and 67 in the Boí valleys. The local topography and microclimate conditions lead to substantial differences in both areas in terms of the morphology and dimensions of the cirques. Glacial cirques in Boí are distributed at slightly higher elevations than in Aran and they are also larger, though their dimensions decrease with elevation in both valleys. Aran cirques are mostly oriented NE, while Boí landforms do not show any prevailing aspect. Even though lithology does not control the distribution of the glacial cirques, some specific lithological settings may favour the development of larger cirques. In general, glacial cirques in the Aran and the Boí valleys show morphometrical properties similar to those reported in other mid-latitude mountain ranges.

关键词： Central Pyrenees Aran and Boi valleys glacial cirques topography morphometry.

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Impairment of pre-mRNA splicing in liver disease: Mechanisms and consequences

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World Journal of Gastroenterology 2010年第25期16卷 3091-3102页

作者： Carmen Berasain Saioa Gońi Josefa Castillo Maria Ujue Latasa jesús Prieto Matias A Avila Division of Hepatologyand Gene Therapy CIMA University of Navarra Pamplona31008 Spain

Pre-mRNA splicing is an essential step in the process of gene expression in eukaryotes and consists of the removal ofintrons and the linking of exons to generate mature mRNAs. This is a highly regulated mechanism that allows the alternative usage of exons, the retention ofintronic sequences and the generation of exonic sequences of variable length. Most human genes undergo splicing events, and disruptions of this process have been associated with a variety of diseases, including cancer. Hepatocellular carcinoma (HCC) is a molecularly heterogeneous type of tumor that usually develops in a cirrhotic liver. Alterations in pre-mRNA splicing of some genes have been observed in liver cancer, and although still scarce, the available data suggest that splicing defects may have a role in hepatocarcinogenesis. Here we briefly review the general mechanisms that regulatepre-mRNA splicing, and discuss some examples that illustrate how this process is impaired in liver tumorigenesis, and may contribute to HCC development. We believe that a more thorough examination of pre-mRNA splicing is still needed to accurately draw the molecular portrait of liver cancer. This will surely contribute to a better understanding of the disease and to the development of new effective therapies.

关键词： Cell signalling Hepatocarcinogenesis PremRNA splicing Splicing factors Targeted anticancer therapy

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QoS in FANET Business and Swarm Data

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Computers, Materials & Continua 2022年第7期72卷 1877-1899页

作者： jesús Hamilton Ortiz Carlos Andrés Tavera Romero Bazil Taha Ahmed Osamah Ibrahim Khalaf Close Mobile R&D Telecommunications LS MadridEspaña COMBA I+D Research Group of Universidad Santiago de Cali CaliColombia Autonomous of Madrid University MadridEspaña Al-Nahrain Nanorenewable Energy Research Center in Al-Nahrain University BagdadIraq

This article shows the quality of services in a wireless swarm of drones that form an ad hoc network between them Fly Ad Hoc Networks(FANET).Each drone has the ability to send and receive information(like a router);and can behave as a hierarchical node whit the intregration of three protocols:Multiprotocol Label Switch(MPLS),Fast Hierarchical AD Hoc Mobile(FHAM)and Internet Protocol version 6(IPv6),in conclusion MPLS+FHAM+*** metrics analyzed in the FANET are:delay,jitter,throughput,lost and sent packets/*** process was carried out with swarms composed of 10,20,30 and 40 units;In this work,the stage with 40 droneswas analyzed showing registration processes,and sentmessages sequences between different drones that were part of the same swarm.A special analysis about the traffic between drones(end-to-end)was carried out,as well as the possible security flaws in each drone and the current status and future trends in real *** future trends,in a real environment,we took as a starting point,metrics results obtained in the simulation(positive according to the obtained results).These results gave us a clear vision of how the network will behave in a real environment with the aim to carry out the experiment on a physical level in the near *** work also shows the experience quality from the service quality metrics obtained through a mathematical *** quality of experience model will allow us to use it objectively in the agricultural sector,which is a great interest area and is where we are working with *** in this article we show our advances for a business model applied to the aforementioned agricultural sector,as well as the data analysis and services available to the end *** services available to the end customer have been classified into a basic,medium,advanced and plus level.

关键词： Ad hoc home agent(AHA) ad hoc mobile node(AMN) ad hoc correspondent node(ACN) ad hoc mobile anchor point(AMAP) fast hierarchical AD hoc mobile IPv6(FHAMIPv6) label switching router(LSR)label edge router(LER) mobile ad hoc networks(MANET)fly ad hoc network(FANET) quality of services(QoS) quality of experience(QoE)

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Predictors of functional benefit of hepatitis C therapy in a‘real-life’cohort

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World Journal of Gastroenterology 2018年第7期24卷 852-861页

作者： niels Steinebrunner Kerstin Stein Catharina Sandig Thomas Bruckner Wolfgang Stremmel Anita Pathil Department of Internal Medicine IV University Hospital HeidelbergHeidelberg 69120Germany Department of Gastroenterology Hepatology and Infectious DiseasesUniversity Hospital of MagdeburgMagdeburg 39120Germany Department of Medical Biometry Institute of Medical Biometry and Informatics(IMBI)Heidelberg 69120Germany

AIM To define predictors of functional benefit of direct-acting antivirals(DAAs) in patients with chronic hepatitis C virus(HCV) infection and liver *** We analysed a cohort of 199 patients with chronic HCV genotype 1, 2, 3 and 4 infection involving previously treated and untreated patients with compensated(76%) and decompensated(24%) liver cirrhosis at two tertiary centres in Germany. Patients were included withtreatment initiation between February 2014 and August 2016. All patients received a combination regimen of one or more DAAs for either 12 or 24 wk. Predictors of functional benefit were assessed in a univariable as well as multivariable model by binary logistic regression *** Viral clearance was achieved in 88%(175/199) of patients. Sustained virological response(SVR) 12 rates were as follows: among 156 patients with genotype 1 infection the SVR 12 rate was 90%(n = 141); among 7 patients with genotype 2 infection the SVR 12 rate was 57%(n = 4); among 30 patients with genotype 3 infection the SVR 12 rate was 87%(n = 26); and among 6 patients with genotype 4 infection the SVR 12 rate was 67%(n = 4). Follow-up MELD scores were available for 179 patients. A MELD score improvement was observed in 37%(65/179) of patients, no change of MELD score in 41%(74/179) of patients, and an aggravation was observed in 22%(40/179) of patients. We analysed predictors of functional benefit from antiviral therapy in our patients beyond viral eradication. We identified the Child-Pugh score, the MELD score, the number of platelets and the levels of albumin and bilirubin as significant factors for functional *** Our data may contribute to the discussion of potential risks and benefits of antiviral therapy with individual patients infected with HCV and with advanced liver disease.

关键词： functional benefit direct acting antiviral hepatitis C cirrhosis real-life data

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On the Differential Polynomial of a Graph

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Acta Mathematica Sinica,English Series 2019年第3期35卷 338-354页

作者： Ludwin A.BASILIO-HERNáNDEZ Walter CARBALLOSA jesús LEA?OS José M.SIGARRETA Unidad Académica de Matemáticas Universidad Autónoma de Zacatecas Calzada Solidaridad entronque Paseo a la Bufa Department of Mathematics and Statistics Florida International University Department of Mathematics Miami Dade College Facultad de Matemáticas Universidad Autónoma de Guerrero

We introduce the differential polynomial of a graph. The differential polynomial of a graph G of order n is the polynomial B(G; x) :=∑?(G)k=-nB_k(G) x^(n+k), where B_k(G) denotes the number of vertex subsets of G with differential equal to k. We state some properties of B(G;x) and its *** particular, we compute the differential polynomial for complete, empty, path, cycle, wheel and double star graphs. We also establish some relationships between B(G; x) and the differential polynomials of graphs which result by removing, adding, and subdividing an edge from G.

关键词： Graph polynomial differential of a graph

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Influence of oxidation of automatic transmission fluids (ATFs) and sliding distance on friction coefficients of a wet clutch in the running-in stage

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Friction 2021年第2期9卷 401-414页

作者： Leonardo Israel FARFAN-CABRERA Ezequiel Alberto GALLARDO-HERNÁNDEZ Manuel VITE-TORRES jesús Gilberto GODÍNEZ-SALCEDO Tecnologico de Monterrey Escuela de Ingeniería y CienciasAve.Eugenio Garza Sada 2501Monterrey 64849México Instituto Politécnico Nacional SEPI-Escuela Superior de Ingeniería Mecánica y EléctricaUnidad ZacatencoGrupo de TribologíaCol.LindavistaCiudad de México 07738México Instituto Politécnico Nacional ESIQIEIPNCol.LindavistaCiudad de México 07738México

In this paper,the influence of oxidation of automatic transmission fluids(ATFs)and sliding distance on the friction coefficients of a wet clutch in approached running-in conditions was *** ATFs were oxidized by a laboratory process approaching oxidation occurred in actual *** was evaluated by means of increase in carbonyl compounds and depletion of zinc dialkyldithiophosphates(ZDDPs)***,the changes in kinematic viscosity and viscosity index were ***-ondisk tests were conducted to replicate the actual sliding contact in a wet *** pin specimens were cut from friction material composite plates and the disks were actual steel separators both from an automotive wet *** coefficient, μ,was measured at progressive sliding velocity,ν,to obtain μ–νcurves at 26 and 100°*** μ–νtests were consecutively run using the same pair of specimens and *** cumulative sliding distance for each μ–νtest generated surface flattening using the *** friction coefficients of the wet clutch increased due to the ATFs oxidation meanwhile the dm/dv values decreased in most *** suggests that ATF oxidation can enhance torque capacity of the wet clutch,but it could reduce anti-shudder *** sliding distance improved the slopes in the μ–νresults using fresh ATFs meanwhile it generated a slope decrease by using aged ATFs.

关键词： wet clutch friction oil oxidation automatic transmission fluid(ATF)

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