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内部生态系统反馈加重了固氮蓝藻细菌藻华并使波罗的海管理复杂化

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AMBIO－人类环境杂志 2007年第2期36卷 178-185页

作者： Emil Vahtera Daniel J.Conley Bo g.gustafsson Harri Kuosa Heikki Pitknen Oleg P.Savchuk Timo Tamminen Markku Viitasalo Maren Voss Norbert Wasmund Fredrik Wulff 陈欣然芬兰海洋研究院隆德大学地圈生物圈中心哥德堡大学地球科学中心芬兰首都赫尔辛基大学Tvrminne动物站芬兰环境研究院瑞典斯德哥尔摩大学系统生态学系芬兰环境研究院(SYKE) FIMR WarnemUünde的波罗的海研究院生物海洋学系 Warnemünde的波罗的海研究院斯德哥尔摩大学系统生态学系

波罗的海的富营养化可能已潜在地增加了蓝藻细菌藻华发生的频率和规模。富营养化导致有机沉积物的增加,底层缺氧状况的加剧以及随后的系统内磷负荷的加重。此外,低氧水体积呈现与无机氮库负相关的关系,提示随低氧程度的增加,总氮的消除... 详细信息

波罗的海的富营养化可能已潜在地增加了蓝藻细菌藻华发生的频率和规模。富营养化导致有机沉积物的增加,底层缺氧状况的加剧以及随后的系统内磷负荷的加重。此外,低氧水体积呈现与无机氮库负相关的关系,提示随低氧程度的增加,总氮的消除也会增加。系统内磷负荷加重和溶解的无机氮消除的增加将导致较低的氮磷比,而低的氮磷比是促进固氮蓝藻细菌藻华发生的主要原因之一。因为波罗的海开阔水域的蓝藻细菌藻华似乎被其内部作用所强有力地调控,因此,外部营养物质消减的影响与尺度相关。在较长的时间尺度上,外部磷负荷的减少可能会降低蓝藻细菌藻华的发生;然而,在较短时间尺度上,内部磷负荷可能会抵消外部磷负荷的降低。这些可诱导内部负荷(增加)、氮清除以及固氮蓝藻细菌占优势的耦合的过程,可被定性地描述为一种具有潜在自驱式的"恶性循环"。为了有效抑制蓝藻细菌藻华以及所有的富营养化征象,削减氮和磷外部负荷似乎是至关重要的。

关键词：蓝藻细菌波罗的海生态系统藻华固氮杂化管理反馈

Multiple Flux Rope Events on Jan.26,2001Observed at High-Latitude Magnetopause:Cluster/RAPID Measurements（Ⅱ）

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Multiple Flux Rope Events on Jan.26,2001Observed at High-Lat...

The Work of David gottlieb:A Success Story

中国地球空间双星探测计划科学研讨会

作者： Z.Y.Pu Z.Q.gang Z.Y.Huang T.Fritz C.J.Xiao S.Y.Fu L.Xie Q.Q.Shi J.B.Cao Z.X.Liu P.Daly A.Balogh K.H.glassmeier H.Reme J.Dandouras g.gustafsson

＜正＞ On January 26,2001ClusterⅡ4 satellites remained nearthe dusk-side high-latiude magnetopause for more than *** position of spacecraft in the gSE coordinatesystem was around x～4RE,y～7RE and z～*** to the recon...

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Communications in Computational Physics 2011年第3期9卷 481-496页

作者： Bertil gustafsson Division of Scientific Computing Uppsala UniversityBox 337SE-75105 UppsalaSweden

This article is a brief survey of David gottlieb’s extraordinary research *** is impossible to give a thorough presentation of all his research and the impact of his work,but we shall describe the main contributions and give examples of the results in some of his *** was for many years the dominating person in the development of spectral methods,and we devote much of the space in this article to this field.

关键词： Work David devote

Form factor measurements with ANDA at FAIR

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Chinese Physics C 2010年第6期34卷 863-868页

作者： E.Tomasi-gustafsson CEA IRFUSPhNSaclay91191 Gif-sur-Yvette CedexFranceand CNRS/IN2P3Institut de Physique NuclaireUMR 860891406 OrsayFrance

The high intensity and high energy antiproton beams which will be produced at FAIR open the possibility to determine time-like electromagnetic form factors in a wide kinematical range, through the annihilation reaction： p ＋ p → e^＋＋ e^-. The status of the proposed experiment as well as the expected results are presented on the basis of realistic simulations. The impact of these measurements on the understanding of the nucleon structure, of the asymptotic properties of form factors and of the reaction mechanism are discussed using model independent statements based on symmetry properties of the strong and electromagnetic interactions in connection with space-like data.

关键词： electromagnetic form factors antiprotons nucleon structure QCD

Bottom-up approaches to microLEDs emitting red, green and blue light based on gaN nanowires and relaxed IngaN platelets

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Chinese Physics B 2023年第1期32卷 1-10页

作者：毕朝霞 Anders gustafsson Lars Samuelson Anders gustafsson and Lars Samuelson Division of Solid State Physics and NanoLundLund UniversityBox 118SE-22100 LundSweden

Miniaturization of light-emitting diodes(LEDs) with sizes down to a few micrometers has become a hot topic in both academia and industry due to their attractive applications on self-emissive displays for high-definition televisions,augmented/mixed realities and head-up displays, and also on optogenetics, high-speed light communication, etc. The conventional top-down technology uses dry etching to define the LED size, leading to damage to the LED side *** sizes of microLEDs approach the carrier diffusion length, the damaged side walls play an important role, reducing microLED performance significantly from that of large area LEDs. In this paper, we review our efforts on realization of microLEDs by direct bottom-up growth, based on selective area metal–organic vapor phase epitaxy. The individual LEDs based on either gaN nanowires or IngaN platelets are smaller than 1 μm in our approach. Such nano-LEDs can be used as building blocks in arrays to assemble microLEDs with different sizes, avoiding the side wall damage by dry etching encountered for the top-down approach. The technology of IngaN platelets is especially interesting since IngaN quantum wells emitting red, green and blue light can be grown on such platelets with a low-level of strain by changing the indium content in the IngaN platelets. This technology is therefore very attractive for highly efficient microLEDs of three primary colors for displays.

关键词： microLEDs RgB gaN IngaN

A metamodel for heritage-based urban recovery

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Built Heritage 2023年第2期7卷 26-49页

作者： Christer gustafsson Matthias Ripp Department of Art History Uppsala University(SE)UppsalaSweden. Department of Archives&Preservation of Historical Monuments City of Regensburg(DE) RegensburgGermany.

Purpose:The purpose of this paper is to discuss the potential transfer of a metamodel for heritage-based urban development(HBUD)in a postcrisis urban recovery ***/methodology/approach:After an introduction to the feld of cultural heritage as a resource for urban development,the research question is elaborated,and the current understanding of urban heritage is *** use of the metamodel in a postcrisis urban recovery setting is described as a potential *** proposed metamodel is introduced along with the grounded theory and design research methodology through which it was *** specifc qualities of metamodels and how they can contribute to the proposed use are *** scenario is then developed further,and specifc ways in which the metamodel could contribute are ***,the metamodel is compared to other methods,such as the historic urban landscape(HUL)approach,and the limitations are ***:The metamodel can potentially be used in a postcrisis urban recovery *** metamodel cannot be used directly,owing to the nature of metamodels;however,it can be transferred to a specifc context and help to structure successful heritage-based urban recovery(HBUR)*** limitations/implications:One limitation is that it can be difcult to understand the diferences between models and *** with a comprehensive understanding of the nature of metamodels can this metamodel be applied,for example,to select appropriate models for *** metamodel can help to ensure that all relevant‘elements’are part of the processes designed for HBUR and emphasise the need for thorough planning,or scoping,of such ***/value:Metamodelling has not previously been used for HBUD or HBUR.

关键词： Urban heritage Recovery Resilience Sustainable development Metamodel Conservation

Modeling of shear walls using finite shear connector elements based on continuum plasticity

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Frontiers of Structural and Civil Engineering 2017年第2期11卷 143-157页

作者： Ulf Arne gIRHAMMAR Per Johan gustafsson Bo KALLSNER Division of Wood Science and Engineering Lulea University of Technology Skellefiea 93187 Sweden Division of Structural Mechanics Department of Building Sciences Lund University Lund 22100 Sweden Department of Building Technology Linnceus University Vaxjo 35195 Sweden

Light-frame timber buildings are often stabilized against lateral loads by using diaphragm action of roofs, floors and walls. The mechanical behavior of the sheathing-to-framing joints has a significant impact on the structural performance of shear walls. Most sheathing-to-framing joints show nonlinear load-displacement characteristics with plastic behavior. This paper is focused on the finite element modeling of shear walls. The purpose is to present a new shear connector element based on the theory of continuum plasticity. The incremental load-displacement relationship is derived based on the elastic-plastic stiffness tensor including the elastic stiffness tensor, the plastic modulus, a function representing the yield criterion and a hardening rule, and function representing the plastic potential. The plastic properties are determined from experimental results obtained from testing actual connections. Load-displacement curves for shear walls are calculated using the shear connector model and they are compared with experimental and other computational results. Also, the ultimate horizontal load-carrying capacity is compared to results obtained by an analytical plastic design method. good agreements are found.

关键词： shear walls wall diaphragms finite element modelling plastic shear connector analytical modelling exoerimental comoarison

High level of deoxycholic acid in human bile does not promote cholesterol gallstone formation

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World Journal of gastroenterology 2003年第7期9卷 1576-1579页

作者： Ulf gustafsson Staffan Sahlin Curt Einarsson Department of Surgery Danderyd HospitalStockholmSweden Division of gastroenterology and Hepatology Department of MedicineHuddinge University HospitalKarolinska InstitutetStockholmSweden

AIM:To study whether patients with excess deoxycholic acid (DCA) differ from those with normal percentage of DCA with respect to biliary lipid composition and cholesterol saturation of gallbladder bile. METHODS:Bile was collected during operation through puncturing into the gallbladder from 122 cholesterol gallstone patients and 46 gallstone-free subjects undergoing *** data,biliary lipids,bile add composition, presence of crystals and nucleation time were analyzed. RESULTS:A subgroup of gallstone patients displayed a higher proportion of DCA in bile than gallstone free subjects. By choosing a cut-off level of the 90th percentile,a group of 13 gallstone patients with high DCA levels (mean 50 percent of total bile acids) and a large group of 109 patients with normal DCA levels (mean 21 percent of total bile acids) were *** mean age of the patients with high DCA levels was higher than that of the group with normal levels (mean age:62 years vs45 years) and so was the mean BMI (28.3 vs.24.7).Plasma levels of cholesterol and triglycerides were slightly higher in the DCA excess groups compared with those in the normal DCA *** was no difference in biliary lipid composition,cholesterol saturation,nucleation time or occurrence of cholesterol crystals in bile between patients with high and normal levels of DCA. CONCLUSION:gallstone patients with excess DCA were of older age and had higher BMI than patients with normal *** two groups of patients did not differ with respect to biliary lipid composition,cholesterol saturation,nucleation time or occurrence of cholesterol *** is concluded that DCA in bile does not seem to contribute to gallstone formation in cholesterol gallstone patients.

关键词： Adolescent Adult Aged Aged, 80 and over Bile Body Mass Index Cholesterol Crystallization Deoxycholic Acid Female gallstones Humans Lipids Male Middle Aged Research Support, Non-U.S. gov't

Update on the management of pancreatic cancer:Surgery is not enough

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World Journal of gastroenterology 2015年第11期21卷 3157-3165页

作者： Daniel Ansari Adam gustafsson Roland Andersson Department of Surgery Clinical Sciences LundLund University and Sk?ne University Hospital

Pancreatic ductal adenocarcinoma(PDAC) represents the fourth cause of death in cancer and has a 5-year survival of < 5%.Only about 15% of the patients present with a resectable PDAC with potential to undergo "curative... 详细信息

Pancreatic ductal adenocarcinoma(PDAC) represents the fourth cause of death in cancer and has a 5-year survival of go "curative" *** surgery,local and systemic recurrence,is though very *** median survival of resected patients with adjuvant chemotherapy after surgery is only 20-23 *** underscores the significant need to improve PDAC management *** survival rate is dependent on new breakthroughs in our understanding of not at least tumor *** aim of this review is to update and comment on recent knowledge concerning PDAC biology and new diagnostics and treatment *** fundamental approach to improve survival rates is by earlier and improved diagnosis of the *** recent years,novel blood-based biomarkers have emerged based on genetic,epigenetic and protein changes in PDAC with very promising *** biomarkers to enter clinical practice they need to have been developed using adequate control groups and provide high sensitivity and specificity and by this identify patients at risk already in a pre-symptomatic *** way to improve outcomes,is by employing neoadjuvant treatments thereby increasing the number of resectable *** systemic treatment regimes like FOLFIRINOX and nab-paclitaxel have demonstrated improvements in prolonging survival in advanced cases,but long-term survival is still *** future improved understanding of PDAC biology will inevitably render new treatment options directed against both the cancer cells and the surrounding microenvironment.

关键词： Pancreatic cancer Diagnosis genetics Epigenetics P