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Traceable long range scanning tunneling microscopy

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Optoelectronics Letters 2008年第1期4卷 49-50页

作者： A. Weckenmann J. hoffmann Chair Quality Management and Manufacturing Metrology University of Erlangen-Nuremberg

Dimensionally correct and directly traceable measurement is not feasible with conventional scanning tunneling microscopy (STMs) due to severe hysteresis and non-linearity of the commonly applied piezo tube scanners and the very short range. By integrating a custom made probing system based on tunneling current measurement into a commercially available and laser-interferometrically position controlled positioning system, an STM with a principal measuring

关键词：远程扫描隧道显微镜显微镜技术干涉测量激光定位控制

Reduced multibody system transfer matrix method using decoupled hinge equations

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International Journal of Mechanical System Dynamics 2021年第2期1卷 182-193页

作者： Xue Rui dieter Bestle Engineering Mechanics and Vehicle Dynamics Brandenburg University of TechnologyCottbusGermany Institute of Launch Dynamics Nanjing University of Science and TechnologyNanjingChina

In the multibody system transfer matrix method(MSTMM),the transfer matrix of body elements may be directly obtained from kinematic and kinetic ***,regarding the transfer matrices of hinge elements,typically information of their outboard body is involved complicating modeling and even resulting in combinatorial problems *** types of outboard body's output *** problem may be resolved by formulating decoupled hinge equations and introducing the Riccati transformation in the new version of MSTMM called the reduced multibody system transfer matrix method in this *** procedures for chain,tree,closed-loop,and arbitrary general systems are defined,respectively,to generate the overall system equations satisfying the boundary conditions of the system during the entire computational *** a result,accumulation errors are avoided and computational stability is guaranteed even for huge systems with long chains as demonstrated by examples and comparison with commercial software automatic dynamic analysis of the mechanical system.

关键词： general system topology multibody system dynamics reduced transformation transfer matrix method

Bad neighborhoods:apoptotic and necroptotic microenvironments determine liver cancer subtypes

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Hepatobiliary Surgery and Nutrition 2019年第4期8卷 404-406页

作者： dieter Adam Institut fur Immunologie Christian-Albrechts-Universitat zu KielKielGermany

Cancer and cell death are inextricably intertwined. Impaired cell death is a prerequisite for cancer development, and artificial induction of cell death is a key strategy in cancer therapy. At present, clinical approaches to kill tumor cells mostly rely on the induction of apoptosis. For many years, apoptosis has been regarded as the only physiologic form of cell suicide. However, over the last two decades, it has become clear that alternative forms of regulated cell death exist which operate via distinct molecular mechanisms. Therefore, these novel forms of non-apoptotic cell death represent putative therapeutic options to overcome apoptosis resistance of cancer cells, potentially paving the way to more effective tumor therapies (1-3). Representing the currently best studied form of non-apoptotic cell death, necroptosis is elicited by triggers such as death receptors, toll like receptors (TLR) or sensors for intracellular nucleic acids (1,4,5). Their signals converge on the phosphorylation/activation of receptor-interacting serine/threonine protein kinase 3 (RIPK3). Phosphorylation of mixed-lineage kinase domain-like (MLKL) by RIPK3 results in oligomerization and membrane translocation of MLKL and subsequent rupture of the plasma membrane. The release of damage-associated molecular patterns (DAMPs) from the bursting necroptotic cells then promotes inflammation and activation of the innate and adaptive immune response (4-6).

关键词： cancer inflammation neighborhood

Age Structure and Growth of Degraded Populus euphratica Floodplain Forests in North-west China and Perspectives for Their Recovery

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Journal of Integrative Plant Biology 2008年第5期50卷 536-546页

作者： Janneke Westermann Stefan Zerbe dieter Eckstein Technical University of Berlin Institute of EcologyRothenburgstraβe 12D-12165 BerlinGermany University of Greifswald Institute of Botany and Landscape EcologyGrimmer Straβe 88D-17487 GreifswaldGermany University of Hamburg Department of Wood ScienceDivision of Wood BiologyLeuschnerstraβe 91D-21031 HamburgGermany

The Populus euphratica floodplain forests along the lower reaches of the Tarim River in continental-arid Xinjiang （northwest China） have been declining in recent decades as a result of dam constructions and the withdrawal of water from the river. Since 2000, controlled flooding has been carried out to counteract this process of degradation. However, the consequences of a changing water regime for the floodplain ecosystem are not yet sufficiently investigated. In 2004 we sampled a total of 150 P. euphratica trees along two transects at the middle and lower reaches of the Tarim River to compare the age structure and growth of these two tree populations. The anthropogenic drawdown of the groundwater table had no effect on the average growth of the trees at the lower reaches. However, tree growth abruptly increased after controlled flooding, thus showing distinct signs of recovery.

关键词： arid land controlled flooding Euphrates poplar human impact Populus euphratica tree rings.

Epigenetic Repression of Male Gametophyte- Specific Genes in the Arabidopsis Sporophyte

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Molecular Plant 2013年第4期6卷 1176-1186页

作者： Robert D. hoffmann Michael G. Palmgren Centre for Membrane Pumps in Cells and Disease--PUMPKIN Danish National Research Foundation Department of Plant and Environmental SciencesUniversity of Copenhagen Thorvaldsensvej 40 DK-1871 Frederiksberg Denmark

Tissue formation, the identity of cells, and the functions they fulfill, are results of gene regulation. The male gametophyte of plants, pollen, is outstanding in this respect as several hundred genes expressed in pollen are not expressed in the sporophyte. How pollen-specific genes are down-regulated in the sporophyte has yet to be established. In this study, we have performed a bioinformatics analysis of publicly available genome-wide epigenetics data of sev- eral sporophytic tissues. By combining this analysis with DNase ! footprinting data, we assessed means by which the repression of pollen-specific genes in the Arabidopsis sporophyte is conferred. Our findings show that, in seedlings, the majority of pollen-specific genes are associated with histone-3 marked by mono- or trimethylation of Lys-27 （H3K27me1/ H3K27me3）, both of which are repressive markers for gene expression in the sporophyte. Analysis of DNase footprint profiles of pollen-specific genes in the sporophyte displayed closed chromatin proximal to the start codon. We describe a model of two-staged gene regulation in which a lack of nucleosome-free regions in promoters and histone modifications in open reading frames repress pollen-specific genes in the sporophyte.

关键词： male gametophyte epigenetics gene repression DNase I footprinting transcription factors bioinformatics.

Gas exchange of Populus euphratica leaves in a riparian zone

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Journal of Arid Land 2013年第4期5卷 531-541页

作者： dieter OVERDIECK Daniel ZICHE RuiDe YU Institute of Ecology/Ecology of Woody Plants TU-BerlinD-14195 BerlinGermany von Thuenen-Institut Institute of Forest Ecology and Forest InventoryD-16225 EberswaldeGermany Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences

Riparian vegetation belts in arid regions of Central Asia are endangered to lose their ecosystem services due to intensified land *** the development of sustained land use,management knowledge of plant performance in relation to resource supply is *** estimated productivity related functional traits at the edges of the habitat of Populus euphratica *** leaf area （SLA） and carbon/nitrogen （C/N） ratio of *** leaves growing near a former river bank and close to moving sand dunes in the Ebinur Lake National Nature Reserve in Xinjiang,Northwest China （near Kazakhstan） were determined and daily courses of CO2 net assimilation （PN）,transpiration （E）,and stomatal conductance （gs） of two consecutive seasons were measured during July-August 2007 and June-July *** level was high （1.5-2.5 m below ground） throughout the years and no flooding occurred at the two tree *** was slightly lower near the desert than at the former river bank and leaves contained less N in relation to *** E and gs of *** were reached in the morning before noon on both stands and a second low maximum occurred in the afternoon despite of the unchanged high levels of air to leaf water vapor pressure deficit （ALVPD）.Decline of gs in *** was followed by decrease of *** use efficiency （WUE） of leaves near the desert were higher in the morning and the evening,in contrast to leaves from the former river bank that maintained an almost stable level throughout the *** light compensation points and high light saturation levels of PN indicated the characteristics of leaves well-adapted to intensive irradiation at both *** general,leaves of *** decreased their gs beyond 20 Pa/kPa ALVPD in order to limit water *** of E did not occur in both stands until 40 Pa/kPa ALVPD was *** stomatal closure of *** was achieved at 60 Pa/kPa ALVPD in both stands.E through the leaf surface amounted up to 30％ of

关键词： Populus euphratica water vapor pressure deficit transpiration stomatal conductance water use efficiency leaf functional traits

Rapid Identification of Rice Samples Using an Electronic Nose

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Journal of Bionic Engineering 2009年第3期6卷 290-297页

作者： John Westbrook W.C.hoffmann R.E.Lacey USDA-ARS College Station Department of Biological and Agricultural Engineering Texas A&M UniversityCollege Station

Four rice samples of long grain type were tested using an electronic nose (Cyranose-320).Samples of 5 g of each variety of rice were placed individually in vials and were analyzed with the electronic nose unit consisting of 32 polymer *** Cyranose-320 was able to differentiate between varieties of *** chemical composition of the rice odors for differentiating rice samples needs to be *** optimum parameter settings should be considered during the Cyranose-320 training process especially for multiple samples,which are helpful for obtaining an accurate training model to improve identification ***,it is necessary to investigate the E-nose sensor selection for obtaining better classification accuracy.A re- duced number of sensors could potentially shorten the data processing time,and could be used to establish an application pro- cedure and reduce the cost for a specific electronic *** research is needed for developing analytical procedures that adapt the Cyranose-320 as a tool for testing rice quality.

关键词： rice grain identification electronic nose data analysis pattern recognition

Kinetics of microwave-enhanced oxidation of phenol by hydrogen peroxide

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Frontiers of Environmental Science & Engineering 2011年第1期5卷 57-64页

作者： Deming ZHAO Jie CHENG Michael R.hoffmann College of Chemical Engineering and Materials Science Zhejiang University of TechnologyHangzhou 310032China W.M.Keck Laboratories California Institute of TechnologyPasadenaCA 91125USA

Aqueous solutions of phenol were oxidized by hydrogen peroxide assisted by microwave(MW)irradiation.A simple kinetic model for the overall degradation of phenol in the presence of excess H_(2)O_(2) is proposed in which the degradation rate of phenol is expressed as a linear function of the concentrations of phenol and H_(2)O_(2).A detailed parametric study showed that the degradation rate of phenol increased with increasing[H_(2)O_(2)]until saturation was *** degradation followed apparent zero-order kinetics under MW radiation or H_(2)O_(2) ***,after 90 min of irradiation,the observed kinetics shifted to pseudo first *** overall reaction rates were significantly enhanced in the combined MW/H_(2)O_(2) system,mainly because microwave could accelerate H_(2)O_(2) to generate hydroxyl radical(·OH)and other reactive oxygen *** observed synergetic effects of the MW/H_(2)O_(2) process resulted in an increased in the net reaction rate by a factor of *** hydrogen peroxide is present in a large stoichiometric excess,the time required to achieve complete mineralization is reduced significantly.

关键词： microwave(MW)irradiation hydrogen peroxide phenol synergetic effects kinetic model

Taxonomic confusion of two tramp ant species： Iridomyrmex anceps and Ochetellus glaber are really species complexes

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Current Zoology 2011年第5期57卷 662-667页

作者： Benjamin D. hoffmann Alan N. ANDERSEN Xiang ZHANG CSIRO Ecosystem Sciences Tropical Ecosystems Research Centre PMB 44 Winnellie NT 0822 Australia College of Plant Protection Fujian Agriculture and Forestry University Fuzhou Fujian 350002 China

Many invasive invertebrates belong to unresolved species complexes, and have a history of misidentification and in-appropriate management. Here we detail confusion surrounding the taxonomy and identification of two dolichoderine ant species, Iridomyrmex anceps Roger and OcheteUus glaber Mayr, which are commonly cited in the literature as having been spread widely by human commerce. We provide morphometric data and images strongly suggesting that these two ＂species＂ are instead com- plexes of species that are likely native to many regions where they are purportedly introduced. We take particular interest in the status of species referred to as L anceps and O. glaber in China, as this is the most northerly distribution of both genera. We con-clude by suggesting that many identifications of both species are likely to be unreliable, and we recommend against any manage- ment action aimed at controlling these species under the assumption that they are exotic [Current Zoology 57 （5）： 662-667, 2011].

关键词： Ant Exotic Invasive Invertebrate Management Tramp ant