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Specific changes in the expression of imprinted genes in prostate cancer--implications for cancer progression and epigenetic regulation

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Asian Journal of Andrology 2012年第3期14卷 436-450,I0007页

作者： Teodora Ribarska Klaus-Marius Bastian Annemarie Koch wolfgang A Schulz Department of Urology Heinrich Heine University 40225 Duesseldorf Germany 1

Epigenetic dysregulation comprising DNA hypermethylation and hypomethylation, enhancer of zeste homologue 2 （EZH2） overexpression and altered patterns of histone modifications is associated with the progression of prostate cancer. DNA methylation, EZH2 and histone modifications also ensure the parental-specific monoallelic expression of at least 62 imprinted genes. Although it is therefore tempting to speculate that epigenetic dysregulation may extend to imprinted genes, expression changes in cancerous prostates are only well documented for insulin-like growth factor 2 （IGF2）. A literature and database survey on imprinted genes in prostate cancer suggests that the expression of most imprinted genes remains unchanged despite global disturbances in epigenetic mechanisms. Instead, selective genetic and epigenetic changes appear to lead to the inactivation of a sub-network of imprinted genes, which might function in the prostate to limit cell growth induced via the PI3K/Akt pathway, modulate androgen responses and regulate differentiation. Whereas dysregulation of IGF2 may constitute an early change in prostate carcinogenesis, inactivation of this imprinted gene network is rather associated with cancer progression.

关键词： androgen signalling imprinted genes loss of imprinting PI3K signalling prostate cancer

Mechanically induced phase transformation of zinc sulfide

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Particuology 2015年第1期13卷 1-10页

作者： Cornelia Damm Patrick Armstrong Christian Roβkopf Stefan Romeis wolfgang Peukert University Erlangen-Nuremberg Institute of Particle Technology

Molecular dynamics （MD） simulations of the consecutive compression-decompression cycles ot hexagonal zinc sulfide （wurtzite） nanoparticles predict an irreversible phase transformation to the cubic *** phase transformation commences at the contact area between the particle and the inden- ter and proceeds with the number of compression cycles. Dislocations are visible for a particle size above 5nm. Results from wet grinding and dry powder compression experiments on a commercial wurtzite pigment agree qualitatively with MD simulation predictions. X-ray diffraction patterns reveal that the amount of cubic polymorph in the compressed samples increases with pressure applied to the powder. In comparison with powder compression, wet milling leads to a more pronounced phase transformation. This occurs because the particles are exposed to a large number of stress events by collision with the grinding media, which leads to the formation of defects and new surface crystallites by particle fracture. According to the MD simulations, phase transformation is expected to occur preferentially in surface crystallites because they experience the highest mechanical load. Because of the phase transformation, the wet ground and compressed samples exhibit a lower photo- luminescence intensity than the feed material. In comparison with powder compression, milling reduces the photoluminescence intensity more substantially. This occurs because a higher defect concentration is formed. The defects contribute to the phase transformation and photoluminescence quenching.

关键词： Polymorph transformationZinc sulfide Molecular dynamics simulation Wet milling Powder compression

55 Years of Holographic Non-Destructive Testing and Experimental Stress Analysis:Is there still Progress to be expected?

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Light(Advanced Manufacturing) 2022年第1期3卷 98-113页

作者： wolfgang Osten Giancarlo Pedrini Institute for Applied Optics ITO University Stuttgart Pfaffenwaldring 9 70569 StuttgartGermany

Holographic methods for non-destructive testing,shape measurement,and experimental stress analysis have shown to be versatile tools for the solution of many inspection *** main advantages are the non-contact nature,the non-destructive and areal working principle,the fast response,high sensitivity,resolution and *** contrast to conventional optical techniques such as classical interferometry,the holographic principle of wavefront storage and reconstruction makes it possible to investigate objects with rough ***,the response of various classes of products on operational or artificial load can be examined very *** paper looks back to the history of holographic metrology,honors the inventors of the main principles,discusses criteria for the selection of a proper inspection method,and shows exemplary ***,the main focus is on modern developments that are inspired by the rapid technological process in sensing technology and digitization,on current applications and future challenges.

关键词： Non-Destructive Testing Holography Stress Analysis Digital Holography Speckle Interferometry

Invasion of Prosopis juliflora and its effects on soil physicochemical properties in Afar region,Northeast Ethiopia

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International Soil and Water Conservation Research 2021年第4期9卷 631-638页

作者： Wakshum Shiferaw Sebsebe Demissew Tamrat Bekele Ermias Aynekulu wolfgang Pitroff Arba Minch University College of Agricultural SciencesNatural Resources ManagementP.O.Box 21Arba MinchEthiopia Addis Ababa University College of Natural SciencesPlant Biology and Biodiversity ManagementP.O.Box 3434Addis AbabaEthiopia The World Agroforestry Centre(ICRAF) UN AvenueP.O.Box 30677NairobiKenya College of Agriculture Food and Natural ResourcesUniversity of MissouriColumbiaUSA

Woody species within pastures and savannas are often associated with‘resource islands’characterized by higher fertility under canopies *** aims of this study were to evaluate(1)the effects of Prosopis juliflora on some soil physicochemical properties and(2)the impacts of Prosopis invasion on soil *** soil physicochemical analysis,a total of 104 soil samples from Teru and Yalo Districts were *** soil samples were collected from soil depths of 0-15 cm and 15-30 cm in Prosopis invaded and non-invaded open grazing *** of Prosopis had significantly affected soil pH,exchangeable Na^(+),water soluble Ca^(2+)+Mg^(2+),water soluble Na^(+),and exchangeable sodium percentage in Teru and Yalo Districts(p<0.05).The invasion of Prosopis significantly increased soil pH(1.5%),but decreased exchangeable Na^(+)(24.2%),exchangeable sodium percentage(21.6%),and water soluble Ca^(2+)+Mg^(2+)(39.9%)than non-invaded *** content of Prosopis invaded lands was higher by 19%than non-invaded ***,sand content of soil was higher under non-invaded lands by 5.6%than Prosopis invaded *** results indicated that invasion of Prosopis had positive effects on physicochemical properties and thus conducive for cereal crops and forages.

关键词： Phrase(s):invasion Open grazing lands Prosopis Rangelands reclamation Soil properties

Regional features of topographic relief over the Loess Plateau,China:evidence from ensemble empirical mode decomposition

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Frontiers of Earth Science 2020年第4期14卷 695-710页

作者： Yongjuan Liu Jianjun Cao Liping Wang Xuan Fang wolfgang Wagner School of Environment Science and Spatial Informatics China University of Mining and TechnologyXuzhou221116China School of Geography Science/Key Laboratory of Virtual Geographic Environment of Ministry of Education Nanjing Normal UniversityNanjing210023China School of Environmental Science Nanjing Xiaozhuang UniversityNanjing211171China Department of Geodesy and Geoinformation Vienna University of TechnologyVienna1040Austria

Landforms with similar surface matter compositions,endogenic and exogenic forces,and development histories tend to exhibit significant degrees of self-similarity in morphology and spatial *** loess hill-gully areas,ridges and hills have similar topographic relief characteristics and present nearly periodic variations of similar repeating structures at certain spatial scales,which is termed the topographic relief period(TRP).This is a relatively new concept,which is different from the degree of relief,and describes the fluctuations of the terrain from both horizontal and vertical(cross-section)perspectives,which can be used for in-depth analysis of 2-D topographic relief *** technique provides a new perspective for understanding the macro characteristics and differentiation patterns of loess *** investigate TRP variation features of different landforms on the Loess Plateau,China,by extracting catchment boundary profiles(CBPs)from 5 m resolution digital elevation model(DEM)*** profiles were subjected to temporal-frequency analysis using the ensemble empirical mode decomposition(EEMD)*** results showed that loess landforms are characterized by significant regional topographic relief;the CBP of 14 sample areas exhibited an overall pattern of decreasing TRPs and increasing topographic relief spatial frequencies from south to *** to the TRPs and topographic relief characteristics,the topographic relief of the Loess Plateau was divided into four types that have obvious regional *** findings of this study enrich the theories and methods for digital terrain data analysis of the Loess *** study should undertake a more in-depth investigation regarding the complexity of the region and to address the limitations of the EEMD method.

关键词： catchment boundary profile topographic relief period ensemble empirical mode decomposition Loess Plateau

Strain-modulated ultrafast magneto-optic dynamics of graphene nanoflakes decorated with transition-metal atoms

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Chinese Physics B 2021年第9期30卷 520-527页

作者： Yiming Zhang Jing Liu Chun Li Wei Jin Georgios Lefkidis wolfgang Hubner School of Mechanics Civil Engineering and ArchitectureNorthwestern Polytechnical UniversityXi'an 710072China Department of Physics and Research Center OPTIMAS Technische Universität KaiserslauternP.O.Box 304967653 KaiserslauternGermany Department of Mechanical Engineering University of ManitobaWinnipeg MB R3T 5V6Canada School of Physics and Information Technology Shaanxi Normal UniversityXi'an 710119China

We perform first-principles calculations and coherent laser-matter interaction analyses to investigate the laser-induced ultrafast spin flip on graphene nanoflakes(GNFs)with transition metal elements attached on the boundary[TM&GNFs(TM=Fe,Co,Ni)].It is shown that the spin-flip process on TM&GNFs is highly influenced by the involved element species and the position attached to the ***,taking Ni&GNF as an example,the first-principles tensile test predicts that the variation of the C-Ni bond length plays an important role in the spin density distribution,especially for the low-lying magnetic states,and can therefore dominate the spin-flip *** fastest spin-flip scenario is achieved within 80 fs in a Ni&GNF structure under 10%tensile strain along the C-Ni *** local deformation modulation of spin flip provides the precursory guidance for further study of ultrafast magnetization control in GNFs,which could lead to potential applications in future integrated straintronic devices.

关键词： graphene nanoflakes straintronics spin dynamics strain effect first principles

Michelangelo Wave Packets and Interference Forces

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量子光学学报 2006年第B8期12卷 57-58页

作者： wolfgang P. Schleich Abteilung fur Quantenphysik Universitaet Ulm D89069 Ulm Germany

Lensless light-field imaging through diffuser encoding

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Light(Science & Applications) 2020年第1期9卷 637-645页

作者： Zewei Cai Jiawei Chen Giancarlo Pedrini wolfgang Osten Xiaoli Liu Xiang Peng Institut fur Technische Optik Universitat StuttgartPfaffenwaldring 970569 StuttgartGermany College of Physics and Optoelectronic Engineering Shenzhen University518060 GuangdongShenzhenChina

Microlens array-based light-field imaging has been one of the most commonly used and effective technologies to record high-dimensional optical signals for developing various potential high-performance applications in many ***,the use of a microlens array generally suffers from an intrinsic trade-off between the spatial and angular *** this paper,we concentrate on exploiting a diffuser to explore a novel modality for light-field *** demonstrate that the diffuser can efficiently angularly couple incident light rays into a detected image without needing any *** characterize and analyse this phenomenon,we establish a diffuser-encoding light-field transmission model,in which four-dimensional light fields are mapped into two-dimensional images via a transmission matrix describing the light propagation through the ***,a calibration strategy is designed to flexibly determine the transmission matrix,so that light rays can be computationally decoupled from a detected image with adjustable spatio-angular resolutions,which are unshackled from the resolution limitation of the *** proof-of-concept approach indicates the possibility of using scattering media for lensless four-dimensional light-field recording and processing,not just for two-or three-dimensional imaging.

关键词： scattering light field

Simulation Modeling in Plant Breeding: Principles and Applications

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Agricultural Sciences in China 2007年第8期6卷 908-921页

作者： WANG Jian-kang wolfgang H Pfeiffer Institute of Crop Sciences/National Key Facility for Crop Gene Resources and Genetic lmprovement/CIMMYT China Office Chinese Academy of Agricultural Sciences Beijing 100081 P.R.China 2 HarvestPlus clo the International Center for Tropical Agriculture （CIAT） A. A. 6713 Cali Colombia

Conventional plant breeding largely depends on phenotypic selection and breeder＇s experience, therefore the breeding efficiency is low and the predictions are inaccurate. Along with the fast development in molecular biology and biotechnology, a large amount of biological data is available for genetic studies of important breeding traits in plants, which in turn allows the conduction of genotypic selection in the breeding process. However, gene information has not been effectively used in crop improvement because of the lack of appropriate tools. The simulation approach can utilize the vast and diverse genetic information, predict the cross performance, and compare different selection methods. Thus, the best performing crosses and effective breeding strategies can be identified. QuLine is a computer tool capable of defining a range, from simple to complex genetic models, and simulating breeding processes for developing final advanced lines. On the basis of the results from simulation experiments, breeders can optimize their breeding methodology and greatly improve the breeding efficiency. In this article, the underlying principles of simulation modeling in crop enhancement is initially introduced, following which several applications of QuLine are summarized, by comparing the different selection strategies, the precision parental selection, using known gene information, and the design approach in breeding. Breeding simulation allows the definition of complicated genetic models consisting of multiple alleles, pleiotropy, epistasis, and genes, by environment interaction, and provides a useful tool for breeders, to efficiently use the wide spectrum of genetic data and information available.

关键词： breeding simulation genetic model breeding strategy design breeding