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排序方式: 共有3199条查询结果,搜索用时 218 毫秒
31.
Bernhard Kienesberger Beate Obermüller Georg Singer Barbara Mittl Reingard Grabherr Sigrid Mayrhofer Stefan Heinl Vanessa Stadlbauer Angela Horvath Wolfram Miekisch Patricia Fuchs Ingeborg Klymiuk Holger Till Christoph Castellani 《International journal of molecular sciences》2021,22(12)
We aimed to assess the in vitro antimicrobial activity and the in vivo effect on the murine fecal microbiome and volatile organic compound (VOC) profile of (S)-reutericyclin. The antimicrobial activity of (S)-reutericyclin was tested against Clostridium difficile, Listeria monocytogenes, Escherichia coli, Enterococcus faecium, Staphylococcus aureus, Staphylococcus (S.) epidermidis, Streptococcus agalactiae, Pseudomonas aeruginosa and Propionibacterium acnes. Reutericyclin or water were gavage fed to male BALBc mice for 7 weeks. Thereafter stool samples underwent 16S based microbiome analysis and VOC analysis by gas chromatography mass spectrometry (GC-MS). (S)-reutericyclin inhibited growth of S. epidermidis only. Oral (S)-reutericyclin treatment caused a trend towards reduced alpha diversity. Beta diversity was significantly influenced by reutericyclin. Linear discriminant analysis Effect Size (LEfSe) analysis showed an increase of Streptococcus and Muribaculum as well as a decrease of butyrate producing Ruminoclostridium, Roseburia and Eubacterium in the reutericyclin group. VOC analysis revealed significant increases of pentane and heptane and decreases of 2,3-butanedione and 2-heptanone in reutericyclin animals. The antimicrobial activity of (S)-reutericyclin differs from reports of (R)-reutericyclin with inhibitory effects on a multitude of Gram-positive bacteria reported in the literature. In vivo (S)-reutericyclin treatment led to a microbiome shift towards dysbiosis and distinct alterations of the fecal VOC profile. 相似文献
32.
Dr. Christoph Goebel Prof.?Dr. Hans-Arno Jacobsen Victor del Razo Mag.? Christoph Doblander Dipl.-Ing. Jose Rivera Dipl-Inform.?Wirt Jens Ilg Dr. Christoph Flath Prof.?Dr. Hartmut Schmeck Prof.?Dr. Christof Weinhardt Dipl-Inform. Daniel Pathmaperuma Prof.?Dr. Dr.?h.?c. Hans-Jürgen Appelrath Prof.?Dr. Michael Sonnenschein Prof.?Dr. Sebastian Lehnhoff Prof.?Dr. Oliver Kramer Prof.?Dr. Thorsten Staake Prof.?Dr. Elgar Fleisch Prof.?Dr. Dirk Neumann Prof.?Dr. Jens Strüker Dr. Koray Erek Prof.?Dr. Rüdiger Zarnekow Dr. Holger Ziekow Prof.?Dr. J?rg L?ssig 《WIRTSCHAFTSINFORMATIK》2014,56(1):31-39
Due to the increasing importance of producing and consuming energy more sustainably, Energy Informatics (EI) has evolved into a thriving research area within the CS/IS community. The article attempts to characterize this young and highly dynamic field of research by describing current EI research topics and methods and provides an outlook of how the field might evolve in the future. It is shown that two general research questions have received the most attention so far and are likely to dominate the EI research agenda in the coming years: How to leverage information and communication technology (ICT) to (1) improve energy efficiency, and (2) to integrate decentralized renewable energy sources into the power grid. Selected EI streams are reviewed, highlighting how the respective research questions are broken down into specific research projects and how EI researchers have made contributions based on their individual academic background. 相似文献
33.
Novel image fusion scheme based on dependency measure for robust multispectral palmprint recognition
Multispectral palmprint is considered as an effective biometric modality to accurately recognize a subject with high confidence. This paper presents a novel multispectral palmprint recognition system consisting of three functional blocks namely: (1) novel technique to extract Region of Interest (ROI) from the hand images acquired using a contact less sensor (2) novel image fusion scheme based on dependency measure (3) new scheme for feature extraction and classification. The proposed ROI extraction scheme is based on locating the valley regions between fingers irrespective of the hand pose. We then propose a novel image fusion scheme that combines information from different spectral bands using a Wavelet transform from various sub-bands. We then perform the statistical dependency analysis between these sub-bands to perform fusion either by selection or by weighted fusion. To effectively process the information from the fused image, we perform feature extraction using Log-Gabor transform whose feature dimension is reduced using Kernel Discriminant Analysis (KDA) before performing the classification by employing a Sparse Representation Classifier (SRC). Extensive experiments are carried out on a CASIA multispectral palmprint database that shows the strong superiority of our proposed fusion scheme when benchmarked with contemporary state-of-the-art image fusion schemes. 相似文献
34.
Martin Atzmueller Martin Becker Mark Kibanov Christoph Scholz Stephan Doerfel Andreas Hotho 《New Review of Hypermedia and Multimedia》2014,20(1):53-77
The combination of ubiquitous and social computing is an emerging research area which integrates different but complementary methods, techniques, and tools. In this paper, we focus on the Ubicon platform, its applications, and a large spectrum of analysis results. Ubicon provides an extensible framework for building and hosting applications targeting both ubiquitous and social environments. We summarize the architecture and exemplify its implementation using four real-world applications built on top of Ubicon. In addition, we discuss several scientific experiments in the context of these applications in order to give a better picture of the potential of the framework, and discuss analysis results using several real-world data sets collected utilizing Ubicon. 相似文献
35.
We present a wearable input system which enables interaction through 3D handwriting recognition. Users can write text in the air as if they were using an imaginary blackboard. The handwriting gestures are captured wirelessly by motion sensors applying accelerometers and gyroscopes which are attached to the back of the hand. We propose a two-stage approach for spotting and recognition of handwriting gestures. The spotting stage uses a support vector machine to identify those data segments which contain handwriting. The recognition stage uses hidden Markov models (HMMs) to generate a text representation from the motion sensor data. Individual characters are modeled by HMMs and concatenated to word models. Our system can continuously recognize arbitrary sentences, based on a freely definable vocabulary. A statistical language model is used to enhance recognition performance and to restrict the search space. We show that continuous gesture recognition with inertial sensors is feasible for gesture vocabularies that are several orders of magnitude larger than traditional vocabularies for known systems. In a first experiment, we evaluate the spotting algorithm on a realistic data set including everyday activities. In a second experiment, we report the results from a nine-user experiment on handwritten sentence recognition. Finally, we evaluate the end-to-end system on a small but realistic data set. 相似文献
36.
Metallo-Supramolecular Polymerization: A Route to Easy-To-Process Organic/Inorganic Hybrid Materials
Mark Burnworth Daniel Knapton Stuart J. Rowan Christoph Weder 《Journal of Inorganic and Organometallic Polymers and Materials》2007,17(1):91-103
The self-assembly polymerization of ditopic macromolecules via metal–ligand binding is a facile route for the preparation
of metallo-supramolecular polymers (MSPs). We herein review our recent work focused on the synthesis and investigation of
metallo-supramolecular polymers based on 2,6-bis(1′-methylbenzimidazolyl)pyridine endcapped poly(p-phenylene ethynylene) and poly(p-xylene) macromonomers. These materials are readily solution-processable and display appreciable mechanical properties as
well as other attractive properties such as specific opto/electrical functions or high thermal stability. Our work illustrates
that metallosupramolecular polymerization offers an attractive approach to assemble high-molecular-weight macromolecules from
well-defined, easy to process precursors. Variation of the ditopic ligands and metal ions allows one to easily tailor the
desired properties.
This paper is dedicated to Professor Ian Manners and his scientific accomplishments. 相似文献
37.
Temporal dynamics of social interaction networks as well as the analysis of communities are key aspects to gain a better understanding of the involved processes, important influence factors, their effects, and their structural implications. In this article, we analyze temporal dynamics of contacts and the evolution of communities in networks of face-to-face proximity. As our application context, we consider four scientific coil- ferences. On a structural level, we focus on static and dynamic properties of the contact graphs. Also, we analyze the resulting community structure using state-of-the-art automatic community detection algorithms. Specifically, we analyze tile evolution of contacts and communities over time to consider the stability of the respective conmmnities. Furthermore, we assess different factors which have an influence on the quality of com- munity prediction. Overall, we provide first important insights into the evolution of contacts and communities in face-to-face contact networks. 相似文献
38.
Definition of problem
At least in some cases, testing for aneuploidy as part of preimplantation genetic diagnosis (PGD) can be medically useful for pregnancy care. The current legal situation in Germany seems to not generally exclude PGD to detect a maldistribution of chromosomes in an embryo, but testing would require approval by a PGD ethics committee on a case-by-case basis and a well-reasoned application by the concerned woman. This article examines ethically and legally whether fundamental reasons prevent PGD commissions from admitting requests to perform aneuploidy tests as part of PGD.Arguments
Three constellations – each with differing ethical implications – can be distinguished in which testing for aneuploidy could be considered or could occur: Testing for aneuploidy can (i) be the main reason for in vitro fertilization (IVF), which in itself is not medically indicated; (ii) IVF is done as infertility treatment in which case PGD and aneuploidy testing could be done additionally; or (iii) PGD with IVF is indicated in order to prevent a congenital disease or chromosomal aberration leading to a diagnosis of aneuploidy as an incidental or additional finding. Ethical arguments which could lead to a general rejection of aneuploidy testing are the prevention of discrimination against people with aneuploidy, as well as the protection of embryos. These concerns oppose constellation (i), but do not apply to (ii) and (iii). Yet there are at least three ethical arguments in favour of an admissibility of a request for aneuploidy testing: the “good practice” of IVF, the duty to the emerging child and the parent’s right to have a voice in the discussion.Conclusion
Aneuploidy testing as part of PGD is not ruled out by legal or ethical reasons and should be openly discussed by the relevant German ethics commissions.39.
Christoph Windmeier Felix Flegiel Alexander Döß Ronald Franz Eckhard Schleicher Michael Wiezorek Markus Schubert Uwe Hampel 《化学,工程师,技术》2021,93(7):1119-1125
An optimized equipment design for natural gas processing and liquefaction plants becomes increasingly difficult with changing process conditions: Particularly low values of surface tension create rising challenges on the design of phase separators and column internals. The TERESA test rig at HZDR was designed to allow the investigation of multiphase thermohydraulics and phase separator performance under critical fluid properties in industrial dimensions. A versatile pipe test section is available in DN200 and equipment internals may be tested in a sectional DN300/DN500 test separator. The applied test fluid shows a high vapor-liquid density difference between 1470 and 940 kg m−3, viscosity as low as 0.12 mm2s−1, and surface tension down to 1.3 mN m−1. Volumetric liquid and vapor flow rates may be varied up to 9 and 530 m3h−1 in the test rig, respectively. 相似文献
40.
介绍了一种新型的冷冻海水淡化技术。到2019年末,液化天然气(LNG)生产能力已达4.3亿吨/年。LNG从再气化过程中释放出的巨大冷能量可用于冷冻脱盐过程,以最大限度地降低总能耗。本文采用HYSYS软件设计并仿真了利用LNG冷能的片冰机冷冻海水淡化(FD)过程。采用片冰机上的制冰桶作为海水结晶器,主要是由于其连续制冰和除冰无热源。利用gPROMS软件建立了冻结段的动态模型并进行了仿真。结果表明,用1kg当量液化天然气冷能可获得1.9~2.1kg的冰融水,该混合工艺的制冷剂泵功率能耗为3.725Wh/100kg,可忽略不计。 相似文献