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Sap flow for beech(Fagus sylvatica L.)in a natural and a managed forest—effect of spatial heterogeneity

Journal of Plant Ecology 2011年第1期4卷 23-35页

作者： Lise Dalsgaard Teis nørgaard Mikkelsen Annemarie Bastrup-Birk Forest and Landscape Faculty of Life SciencesUniversity of CopenhagenRolighedsvej 231958 Frederiksberg CDenmark Risønational Laboratory for Sustainable Energy Technical University of DenmarkFrederiksborgvej 399P.O.Box 494000 RoskildeDenmark

Aims Beech(Fagus sylvatica L.)is an important species in natural and managed forests in *** drought-sensitive species dominates even-aged stands as well more natural stands composed of a mixture of tree species,age and size *** study evaluates the extent that heterogeneity in spacing and tree diameter affect the seasonal availability and use of *** Two stands were evaluated:(i)a heterogeneous forest remnant(nAT)with trees up to;300 years old,a mean top height of 28.4 m and a total of 733 stems ha1with stem diameters averaging 18 cm and(ii)an even-aged 80-year old stand(MAn),with a height of 25 m,and a total of 283 stems ha1 with diameters averaging 38 *** sap flow,Js(g m2 s1),was continuously measured in 12(MAn)and 13(nAT)trees using 20-mm long heat dissipation *** tree measures of sap flow were correlated using non-linear statistical methods with air vapour pressure deficit(D,hPa)and global radiation(Rg,J m2 day1),along with constraints imposed by reductions in soil water content(SWC).SWC was measured as volumetric%using time domain *** Findings The daily integrated Js(Js-sum)for trees growing in the evenly spaced MAn stand and trees in canopy and closed forest positions in nAT stand decreased as the availability of soil moisture was *** the heterogeneous nAT stand,SWC in a recently formed canopy gap remained high throughout the vegetation *** on regression models,the predicted relative decrease in Js-sum for dry relative to moist soil water conditions in the closed forest(at mean daily D=10 hPa)was 7–11%for trees near the gap and 39–42%for trees in the closed *** MAn,the reduction in Js-sum was 29%in dry relative to moist ***-sum in the outer 20 mm of the xylem in nAT was lower than that in MAn and the rate of decline in Js with xylem depth was less in nAT than in *** MAn,Js-sum in deep and outer xylem was negatively affected at low soil moisture availability

关键词： canopy gap canopy structure tree size tree water use

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Laser-induced oxidation assisted micro milling of high aspect ratio microgroove on WC-Co cemented carbide

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Chinese Journal of Aeronautics 2021年第4期34卷 465-475页

作者： Guolong ZHAO Hongjun XIA Yang ZHAnG Liang LI ning HE Hans nφrgaard HAnSEn national Key Laboratory of Science and Technology on Helicopter Transmission Nanjing University of Aeronautics and AstronauticsNanjing 210016China Department of Mechanical Engineering Technical University of DenmarkKgs.Lyngby 2800Denmark

Severe tool wear and poor surface quality are the main problems during micro machining of cemented *** this work,an innovative hybrid process of laser-induced oxidation assisted micro milling(LOMM)was proposed to solve the problems.A nanosecond laser was utilized to induce oxidation of the WC-20%Co material,producing loose oxide which was easy to *** micro machinability of the material was improved by laser-induced *** oxidation mechanisms of cemented carbide were studied.A microgroove with a depth of 2.5 mm and aspect ratio of 5 was fabricated *** milling force,surface quality and tool wear mechanisms were *** comparison,a microgroove was also fabricated with conventional micro milling(COMM)using identical milling *** revealed that in LOMM the milling force and tool wear rate were extremely low during removing the *** machined surface quality and dimensional accuracy achieved by LOMM were superior to those obtained by *** surface roughness Saof the microgroove bottom reached 88 nm in LOMM,while the cross-sectional geometry of the microgroove was a *** of the microgroove sidewall machined by LOMM was better than that by *** tool wear forms in LOMM were coating spalling and slight tool nose *** with COMM,the tool life in LOMM was prolonged *** indicates that the proposed hybrid process is an effective and efficient way to fabricate high aspect ratio micro-features with high dimensional accuracy.

关键词： Cemented carbide High aspect ratio Laser-induced oxidation Micro milling Microgroove Tool wear

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Cutting force model and damage formation mechanism in milling of 70wt%Si/Al composite

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Chinese Journal of Aeronautics 2023年第7期36卷 114-128页

作者： Guolong ZHAO Lianjia XIn Liang LI Yang ZHAnG ning HE Hans nørgaard HAnSEn College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China Department of Civil and Mechanical Engineering Technical University of DenmarkKgs.Lyngby 2800Denmark

High-mass fraction silicon aluminium composite(Si/Al composite) has unique properties of high specific strength, low thermal expansion coefficient, excellent wear resistance and weldability. It has attracted many applications in terms of radar communication, aerospace and automobile industry. However, rapid tool wear resulted from high cutting force and hard abrasion, and damaged machined surfaces are the main problem in machining Si/Al composite. This work aims to reveal the mechanisms of milling-induced damages of 70wt% Si/Al composites. A cutting force analytical model considering the characteristics of both the primary silicon particles and the cutting-edge radius was established. Milling experiments were conducted to verify the validity of the model. The results show that the analytical model exhibits a good consistency with the experimental results, and the error is about 10%. The cutting-edge radius has significant effects on the cutting force, surface roughness and damage formation. With the increase in the cutting-edge radius, both the cutting force and the surface roughness decrease firstly and then increase. When the cutting-edge radius is 27 μm, the surface roughness(Sa) reaches the minimum of 2.3 μ***-induced surface damages mainly contain cracks, pits, scratches, matrix coating and *** damage formation is dominated by the failure mode of primary silicon particles, which includes compressive breakage, intragranular fracture, particle pull-out, and interface debonding. In addition, the high ductility of aluminium matrix leads to matrix coating. This work provides guidance for tool selection and damage inhibition in high-efficiency and high-precision machining of high mass fraction Si/Al composites.

关键词： posite Cutting force analytical model Cutting-edge radius Surface quality Damage formation mechanism

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催化剂对炭黑转变为纳米炭微球和碳管的影响(英文)

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新型炭材料 2015年第1期30卷 19-29页

作者： Vijayshankar Asokan Dorte nφrgaard Madsen Pawel Kosinski Velaug Myrseth The University of Bergen Department of Physics and Technology

以二茂铁和二茂镍为催化剂,采用化学气相沉积法在1 000℃下,炭黑(CB)转变为炭纳米微球和碳管。利用XRD,SEM,TEM,HR-TEM和Raman等对样品进行表征。结果表明,二茂铁和二茂镍质量比不同,可得到形貌不同的纳米炭的结构。与单金属催化剂相比... 详细信息

以二茂铁和二茂镍为催化剂,采用化学气相沉积法在1 000℃下,炭黑(CB)转变为炭纳米微球和碳管。利用XRD,SEM,TEM,HR-TEM和Raman等对样品进行表征。结果表明,二茂铁和二茂镍质量比不同,可得到形貌不同的纳米炭的结构。与单金属催化剂相比,采用双金属催化剂合成的纳米炭结构具有高结晶度。催化剂颗粒填充在碳管内部或包裹在碳管外部,主要取决于催化剂与炭黑的质量比。当炭黑∶二茂铁∶二茂镍为1∶2∶2时,得到结晶度高的催化剂包裹多壁纳米炭微球结构。

关键词：炭黑炭微球碳管催化转变气相沉积

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Loss of mismatch repair signaling impairs the WnT–bone morphogenetic protein crosstalk and the colonic homeostasis

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Journal of Molecular Cell Biology 2020年第6期12卷 410-423页

作者： Katrine nørgaard Carolin Müller nadja Christensen María L.Chiloeches Cesilie L.Madsen Sabine S.nielsen Tine E.Thingholm Antoaneta Belcheva Department of Biochemistry and Molecular Biology University of Southern DenmarkCampusvej 555230 Odense MDenmark Department of Molecular Medicine University of Southern DenmarkJ.B.Winsløws Vej 255230 Odense MDenmark

The fine balance between proliferation,differentiation,and apoptosis in the colonic epithelium is tightly controlled by the interplay between WnT,notch,and bone morphogenetic protein(BMP)*** these complex networks coordinate the colonic homeostasis,especially if cancer predisposing mutations such as mutations in the DnA mismatch repair(MMR)are present,is *** of the MMR system has long been linked to colorectal cancer;however,little is known about its role in the regulation of the colonic *** has been shown that loss of MMR promotes the proliferation of colon epithelial cells that renders them highly susceptible to *** mechanism through which MMR mediates this effect,yet,remains to be *** an MMR-deficient mouse model,we show that increased methylation of Dickkopf1 impacts its expression,and consequently,the ability to negatively regulate WnT *** a result,excessive levels of activeβ-catenin promote strong crypt progenitor-like phenotype and abnormal *** these settings,the development and function of the goblet cells are ***-deficient mice have fewer goblet cells with enlarged mucin-loaded *** further show that MMR inactivation impacts the WnT–BMP signaling crosstalk.

关键词： MMR colonic epithelium WnT BMP crypt homeostasis

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Diamine anchored molecular j unctions of oligo(phenylene ethynylene) cruciform

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Chinese Chemical Letters 2018年第2期29卷 271-275页

作者： Yuqing Liua Marco Santella Zhiqiang Fan Xintai Wang Xiangwei Jiang Mogens Brondsted nielsen Kasper nФrgaard3 Bo W. Laursen Jingbo Li Zhongming Wei State Key Laboratory of Superlattices and Microstructures Institute of Semiconductors Chinese Academy of Sciences Belting 100083 China Sino-Danish College University of Chinese Academy of Science Beijing 100049 China nano-Science Center and Department of Chemistry University of Copenhagen Copenhagen DK-2100 Denmark Sino-Danish Center for Education and Research Beijing 100049 China

Using diamine as anchoring group, the self-assembled monolayers（SAMs） based on oligo（phenyleneethynylene）s（OPEs） and cruciform OPEs with an extended tetrathiafulvalene（TTF）（OPE3 and OPE3-TTF）were successfully formed on the Au substrate. The Uniformity and stability of SAMs were confirmed through cyclic voltammetry（CV） and electrochemical reductive desorption. The investigation of transport properties of SAMs was achieved by conducting-probe atomic force microscopy（CP-AFM） with both Au and Pt tips. The results indicated that the conductance of OPE3-TTF was 17 and 46 times that of OPE3 for Au and Pt tips, respectively. Theoretical calculations are qualitatively consistent with the experimental results, suggesting that the diamine as anchoring group has a great potential in molecular electronics.

关键词： Oligo(phenylene-ethynylene) Tetrathiafulvalene Diamine Molecular electronics Cruciform

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阿梅格尔巴克/哥本山

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城市环境设计 2019年第2期 172-183页

作者： nanna Gyldholm M?ller Alberto Cumerlato Aleksander Wadas Alexander Codda Alexander Ejsing Alexandra Gustafsson Alina Tamosiunaite Armor Gutierrez Anders Hjortn?s Andreas Klok Pedersen Annette Jensen Ariel Wallner Ask Andersen Balaj IIulian Blake Smith Borko nikolic Brygida Zawadzka Buster Christensen Chris Falla Chris Zhongtian Yuan Daniel Selensky Dennis Rasmussen Espen Vik Finn n?rkj?r Franck Fdida Gonzalo Castro Gül Ertekin George Abraham Helen Chen Henrick Poulsen Henrik R?mer Kania Horia Spirescu Jakob Ohm Laursen Jelena Vucic Jeppe Ecklon Ji-young Yoon Jing Xu Joanna Jakubowska Johanna nenander Kamilla Heskje Katarzyna Siedlecka Krzysztof Marciszewski Laura W?tte Liang Wang Lise Jessen Long Zuo Maciej Zawadzki Mads Enggaard Stidsen Marcelina Kolasinska Marcos Bano Maren Allen Mathias Bank matti n?rgaard Michael Andersen narisara Ladawal Schr?der niklas A. Rasch nynne Madsen ?ssur nols? Pero Vukovic Richard Howis Ryohei Koike Se Hyeon Kim Simon Masson Sunming Lee Toni Mateu Xing Xiong Zoltan David Kalaszi Rasmus Hjortshoj 陈子钰

垃圾焚烧发电厂阿梅格尔巴克/哥本山位于工业区,多年来,该工业区已成为冒险者们的极限运动目的地。原始的工业设施为各种极限运动活动提供了场所,如缆绳滑水、卡丁车和攀岩等。阿梅格尔巴克/哥本山是该地区最重要的地标,其建筑亟须更新... 详细信息

垃圾焚烧发电厂阿梅格尔巴克/哥本山位于工业区,多年来,该工业区已成为冒险者们的极限运动目的地。原始的工业设施为各种极限运动活动提供了场所,如缆绳滑水、卡丁车和攀岩等。阿梅格尔巴克/哥本山是该地区最重要的地标,其建筑亟须更新。我们提出了一种新型的垃圾焚烧发电厂,这种工厂能产生经济、环保和社会效益。我们不将阿梅格尔巴克/哥本山视为一个孤立的对象,而是调动起建筑的

关键词：巴克本山

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Continuous cardiac output measured with a Swan-Ganz catheter reacts too slowly in animal experiments with sudden circulatory failure

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Animal Models and Experimental Medicine 2022年第3期5卷 258-265页

作者： Sigríður Olga Magnúsdóttir Carsten Simonsen Bodil Steen Rasmussen Peter Enemark Lund Benedict Kjærgaard Biomedical Research Laboratory Aalborg University HospitalAalborgDenmark Department of Clinical Medicine Aalborg UniversityAalborgDenmark Department of Cardiothoracic Surgery Aalborg University HospitalAalborgDenmark Department of Anesthesia and Intensive Care Aalborg University HospitalAalborgDenmark Unit of Clinical Biostatistics Aalborg University HospitalAalborgDenmark

Background : In many animal experiments, it is vital to detect sudden changes in cardiac output(CO). This porcine study compared CO that was measured with a SwanGanz pulmonary catheter with the gold standard(which was a transit-time flow probe around the pulmonary artery) during interventions that caused hemodynamic *** : In one series, 7 pigs were exposed to sudden changes in CO. In another series, 9 pigs experienced more prolonged changes in CO. All the pigs had a Swan-Ganz catheter placed into the pulmonary artery and a flow probe around the pulmonary artery. Adrenaline infusion and controlled hemorrhage were used to increase and decrease CO, respectively. The measurements of CO before and after each intervention were compared for correlation, agreement, and the time delay that it took each method to detect at least a 30% change in CO. A Bland– Altman test was used to identify correlations and agreements between the *** : In the first series, there was a delay of 5– 7 min for the Swan Ganz catheter to register a 30% change in cardiac output, compared with the flow probe. However,during prolonged changes in CO in the second series, there was a good correlation between the 2 methods. Mixed venous oxygen saturation reacted faster to changes than did CO;both were measured via the Swan-Ganz *** : In many animal studies, the use of Swan-Ganz catheters is suitable;however, in experiments with sudden hemodynamic instability, the flow probe is the most advantageous method for measuring CO.

关键词： cardiac output flow probe hemodynamics pigs Swan-Ganz catheter

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How should liver hypertrophy be stimulated?A comparison of upfront associating liver partition and portal vein ligation for staged hepatectomy(ALPPS)and portal vein embolization(PVE)with rescue possibility

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Hepatobiliary Surgery and nutrition 2021年第1期10卷 1-8页

作者： Ernesto Sparrelid Kristina Hasselgren Bård Ingvald Røsok Peter nørgaard Larsen nicolai Aagaard Schultz Ulrik Carling Eva Fallentin Stefan Gilg Per Sandström Gert Lindell Bergthor Björnsson Department of Clinical Science Intervention and TechnologyDivision of SurgeryKarolinska InstituteKarolinska University HospitalStockholmSweden Department of Surgery and Clinical and Experimental Medicine Linköping UniversityLinköpingSweden Department of Hepato-Pancreato-Biliary Surgery Oslo University HospitalOsloNorway Department of Surgical Gastroenterology and Transplantation RigshospitaletUniversity of CopenhagenDenmark Department of Radiology and nuclear Medicin RikshospitaletOslo University HospitalOsloNorway Department of Radiology RigshospitaletUniversity of CopenhagenCopenhagenDenmark Department of Surgery Skane University HospitalLundSweden

Background:The role of associating liver partition and portal vein ligation for staged hepatectomy(ALPPS)in comparison to portal vein embolization(PVE)is *** aim of this study was to compare successful resection rates(RR)with upfront ALPPS *** with rescue ALPPS on demand and to compare the hypertrophy of the liver between ALPPS and PVE plus subsequent rescue ***:A retrospective analysis of all patients treated with PVE for colorectal liver metastasis(CRLM)or ALPPS(any diagnosis,rescue ALPPS included)at five Scandinavian university hospitals during the years 2013-2016 was conducted.A Chi-square test and a Mann-Whitney U test were used to assess the difference between the groups.A successful RR was defined as liver resection without a 90-day ***:A total of 189 patients were *** RR was in 84.5%of the patients with ALPPS upfront and in 73.3%of the patients with PVE and rescue ALPPS on demand(P=0.080).The hypertrophy of the future liver remnants(FLRs)with ALPPS upfront was 71%(48-97%)compared to 96%(82-113%)after PVE and rescue ALPPS(P=0.010).Conclusions:Upfront ALPPS offers a somewhat higher successful RR than PVE with rescue ALPPS on *** sequential combination of PVE and ALPPS leads to a higher overall degree of hypertrophy than upfront ALPPS.

关键词： Associating liver partition and portal vein ligation for staged hepatectomy(ALPPS) liver surgery colorectal liver metastases(CRLM) portal vein embolization(PVE)

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Patella Alta and Trochlea Dysplasia Is Associated with Abnormal Type Ⅱ Collagen and Matrix Accumulation in Chondrocytes

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Microscopy Research 2014年第2期2卷 19-29页

作者： Peter Storgaard Skagen Thomas Horn Aubrey Milunsky David Dejour Bente St█rgaard Hanne Aagaard Kruse Tom nicolaisen Department of Sports Traumatology Frederikssund HospitalFrederikssundDenmark Department of Pathology Herlev University HospitalHerlevDenmark Boston University School of Medicine Center for Human GeneticsBostonUSA Department of Orthopaedic&Sportmedicine Surgery Lyon-Ortho-Clinic LyonFrance

The purpose of this study was to perform morphological and molecular analyses of articular cartilage from a 14-year-old boy with unusual cartilage lesions, patella alta and trochlea dysplasia in both knee joints and clinically examine two family members (sister, mother), also affected in their knee joints. Biopsies from the boy’s patella were used for: histological examination, Transmission Electron Microscopy (TEM) and DnA sequencing of the COL2A1 gene including Multiplex Ligation-dependent Probe Amplification (MLPA), for detection of DnA deletions and duplications. Clinical and radiological examination showed patella alta and trochlea dysplasia for the brother (type D), sister (type A) and mother (type A) with Insall-Salvati ratios of 1.50, 1.46 and 1.3. Light Microscopy (LM) of biopsies from the patient showed rhomboid chondrocytes in lacuna with deposition of protein aggregates in the ECM. TEM revealed abnormal type II collagen fibrils in aggregates and chondrocytes with abnormal matrix accumulation in rough Endoplasmic Reticulum (rER). Immunostaining showed that type II collagen was deposited intracellularly and in protein aggregates, together with type I collagen, indicating alterations in chondrocyte function and turnover of these molecules. DnA sequencing of 54 exons including extended DnA analysis with MLPA was non-conclusive. Conclusions: We suggest that patella alta and trochlea dysplasia for this patient is associated with collagen accumulation in chondrocytes, abnormal type II collagen heterofibrils in the ECM, cell death and cartilage with subnormal strength and increased risk of premature patellofemoral arthritis. A family with these disorders suggests that phenotype might be transmitted as an autosomal dominant trait.

关键词： Patella Alta Trochlea Dysplasia Matrix Accumulation Endoplasmic Reticulum Storage Disease(ERSD)

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