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Probing turbulence in galaxies with fast radio burst scintillation

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Science China(Physics,mechanics & Astronomy) 2024年第1期67卷 177-178页

作者： James m.cordes Department of Astronomy the Cornell Center for Astrophysics and Planetary ScienceCornell UniversityIthaca NY 14853USA

Interstellar scintillation(ISS)is a well-known phenomenon observed from pulsars in the milky *** comprises intensity variations *** and frequency caused by constructive and destructive interference from multipath propagation,which is due to diffraction from fluctuations in electron density in the interstellar medium(ISm)on scales as small as~100 *** density fluctuations appear to be part of a turbulence process combined with discrete structures in electron density from other astrophysical processes;together these fluctuations extend to scales of pc or larger.

关键词： scales galaxies turbulence

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Assessment of stricturing Crohn's disease:Current clinicalpractice and future avenues

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World Journal of Gastroenterology 2016年第3期22卷 1008-1016页

作者： Dominik Bettenworth Tobias m Nowacki Friederike cordes Boris Buerke Frank Lenze Department of medicine B University Hospital of Muenster48149 MuensterGermany Department of Clinical Radiology University Hospital of Muenster48149 MuensterGermany

Crohn's disease(CD) is a chronic remittent idiopathic disease. Although the early phase of the disease is commonly characterized by inflammation-driven symptoms, such as diarrhea, the frequency of fibrostenotic complications in patients with CD increases over the long-term course of the disease. This review presents the current diagnostic options for assessing CD-associated strictures. In addition to the endoscopic evaluation of CD strictures, this review summarizes the currently available imaging modalities, including ultrasound and cross-sectional imaging techniques. In addition to stricture detection, differentiating between the primarily inflammatory strictures and the predominantly fibrotic ones is essential for selecting the appropriate treatment strategy(anti-inflammatory medical treatment vs endoscopical or surgical approaches). Therefore, recent imaging advances, such as contrast-enhanced ultrasound and ultrasound elastography, contribute to the development of noninvasive non-radiating imaging of CD-associated strictures. Finally, novel magnetic resonance imaging techniques, such as diffusion-weighted, motility and magnetization transfer imaging, as well as 18F-FDG PET/CT, molecular imaging approaches and biomarkers, are critically reviewed with regard to their potential role in assessing stricturing CD.

关键词： Crohn's disease Inflammatory bowel disease Intestinal stricture Endoscopy magnetic resonanceimaging Ultrasound Computed tomography 18F-FDGPET/CT CEUS Elastography

Rational molecular design of efficient yellow-red dendrimer TADF for solution-processed OLEDs: a combined effect of substitution position and strength of the donors

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Science China Chemistry 2024年第5期67卷 1613-1623页

作者： Changfeng Si Dianming Sun Tomas matulaitis David B.cordes Alexandra m.Z.Slawin Eli Zysman-Colman Organic Semiconductor Centre EaStCHEM School of ChemistryUniversity of St AndrewsSt AndrewsKY169STUK

The development of high-performance solution-processed red organic light-emitting diodes(OLEDs) remains a challenge,particularly in terms of maintaining efficiency at high luminance. Here, we designed and synthesized four novel orange-red thermally activated delayed fluorescence(TADF) dendrimers that are solution-processable: 2GCz BP, 2DPACz BP, 2FBP2GCz and 2FBP2DPACz. We systematically investigated the effect of substitution position and strength of donors on the optoelectronic properties. The reverse intersystem crossing rate constant(kRISC) of the emitters having donors substituted at positions 11and 12 of the dibenzo[a,c]phenazine(BP) is more than 10-times faster than that of compounds substituted having donors substituted at positions 3 and 6. Compound 2DPACz BP, containing stronger donors than 2GCz BP, exhibits a red-shifted emission and smaller singlet-triplet energy splitting, ΔE_(ST), of 0.01 e V. The solution-processed OLED with 10 wt% 2DPACz BP doped in m CP emitted at 640 nm and showed a maximum external quantum efficiency(EQE_(max)) of 7.8%, which was effectively maintained out to a luminance of 1,000 cd m-2. Such a device's performance at relevant display luminance is among the highest for solution-processed red TADF OLEDs. The efficiency of the devices was improved significantly by using 4Cz IPN as an assistant dopant in a hyperfluorescence(HF) configuration, where the 2DPACz BP HF device shows an EQEmaxof 20.0% at λEL of 605 nm and remains high at 11.8% at a luminance of 1,000 cd m-2, which makes this device one of the highest efficiency orange-to-red HF SP-OLEDs to date.

关键词： thermally activated delayed fluorescence solution-processing red OLEDs dibenzo[a,c]phenazine dendrimers

Scintillation optics of pulsar binaries and microstructure in the local ionized interstellar medium

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Science China(Physics,mechanics & Astronomy) 2023年第11期66卷 238-238页

作者： James m.cordes Department of Astronomy and the Cornell Center for Astrophysics and Planetary Science Cornell UniversityIthacaNY14853USA

Interstellar scintillation(ISS)caused by scattering from electron density microstructure(?1 AU)provides unequaled spatial resolving power for a number of applications in *** include studies of the interstellar medium on scales as small as 100 km and constraints on emission structure in the magnetospheres of compact objects on similar scales.

关键词： scales interstellar microstructure

Differential regulation of JAK/STAT-signaling in patients with ulcerative colitis and Crohn’s disease

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World Journal of Gastroenterology 2020年第28期26卷 4055-4075页

作者： Friederike cordes Dirk Foell John Nik Ding Georg Varga Dominik Bettenworth Department of medicine B Gastroenterology and HepatologyUniversity Hospital MünsterMünster D-48149Germany Department of Pediatric Rheumatology and Immunology University Children’s Hospital MünsterMünster D-48149Germany Department of Gastroenterology St.Vincent’s HospitalMelbourne 3002Australia Department of medicine University of MelbourneEast Melbourne 3002Australia

In 2018,the pan-Janus kinase(JAK)inhibitor tofacitinib was launched for the treatment of ulcerative colitis(UC).Although tofacitinib has proven efficacious in patients with active UC,it failed in patients with Crohn’s disease(CD).This finding strongly hints at a different contribution of JAK signaling in both ***,we review the current knowledge on the interplay between the JAK/signal transducer and activator of transcription(STAT)pathway and inflammatory bowel diseases(IBD).In particular,we provide a detailed overview of the differences and similarities of JAK/STAT-signaling in UC and CD,highlight the impact of the JAK/STAT pathway in experimental colitis models and summarize the published evidence on JAK/STAT-signaling in immune cells of IBD as well as the genetic association between the JAK/STAT pathway and ***,we describe novel treatment strategies targeting JAK/STAT inhibition in UC and CD and comment on the limitations and challenges of the new drug class.

关键词： Janus kinase Signal transducer and activator of transcription JAK/STAT pathway Inflammatory bowel disease Ulcerative colitis Crohn’s disease JAK/STAT inhibition Tofacitinib

Detection and characterization of murine colitis and carcinogenesis by molecularly targeted contrast-enhanced ultrasound

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World Journal of Gastroenterology 2017年第16期23卷 2899-2911页

作者： markus Brückner Jan Heidemann Tobias m Nowacki Friederike cordes Jorg Stypmann Philipp Lenz Faekah Gohar Andreas Lügering Dominik Bettenworth Department of medicine B University Hospital of MünsterD-48149 MünsterGermany Department of Gastroenterology Klinikum Bielefeld MitteAcademic Teaching HospitalUniversity of MünsterD-33604 BielefeldGermany Department of Cardiology and Angiology University Hospital of MünsterD-48149 MünsterGermany Department of Palliative Care University Hospital of MünsterD-48149 MünsterGermany Department of Paediatric Rheumatology and Immunology University Hospital of MünsterD-48149 MünsterGermany medical Care Center Portal 10 D-48155 MünsterGermany

AIm To study mucosal addressin cellular adhesion molecule-1(mAd CAm-1) and vascular endothelial growth factor(VEGF)-targeted contrast enhanced ultrasound(CEUS) for the assessment of murine colitis and carcinogenesis. mETHODS C57BL/6 mice were challenged with 3% dextran sodium-sulfate(DSS) for three, six or nine days to study the development of acute colitis. Ultrasound was performed with and without the addition of unspecific contrast agents. mAd CAm-1-targeted contrast agent was used to detect and quantify mAd CAm-1 expression. Inflammatory driven colorectal azoxymethane(AOm)/DSS-induced carcinogenesis was examined on day 42 and 84 using VEGF-targeted contrast agent. Highly specific tissue echogenicity was quantified using specialized software. Sonographic findings were correlated to tissue staining, western blot analysis and immunohistochemistry to quantify the degree of inflammation and stage of carcinogenesis. RESULTS Native ultrasound detected increased general bowel wall thickening that correlated with more progressed and more severe DSS-colitis(healthy mice: 0.3 mm ± 0.03 vs six days DSS: 0.5 mm ± 0.2 vs nine days DSS: 0.6 mm ± 0.2, P moreover, these sonographic findings correlated well with clinical parameters such as weight loss(r2 = 0.74) and histological damage(r2 = 0.86)(P murine colitis, CEUS targeted against mAd CAm-1 detected and differentiated stages of mild, moderate and severe colitis via calculation of mean pixel contrast intensity in decibel(9.6 d B ± 1.6 vs 12.9 d B ± 1.4 vs 18 d B ± 3.33, P mploying the AOm/DSSinduced carcinogenesis model, tumor development was monitored by CEUS targeted against VEGF and detected a significantly increased echogenicity in tumors as compared to adjacent healthy mucosa(healthy mucosa, 1.6 d B ± 1.4 vs 42 d, 18.2 d B ± 3.3 vs 84 d, 18.6 d B ± 4.9, P mmunohistochemistry findings(VEGF-posi

关键词： Colitis Dextran sodium-sulfate AOmDSS Carcinogenesis Ultrasound Contrast-enhanced ultrasound Vascular endothelial growth factor mucosal addressin cellular adhesion molecule-1

结节性和弥漫性甲状腺肿B超和同位素扫描的对比研究

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放射学实践 1991年第2期6卷 53-59页

作者： K.Rosenkranz R.Langer m.cordes 乐桂蓉 Radiologische Klinik und Poliklinik Klinikum Rudolf Virchow Standort Charlottenburg Freie Universitt Berlin 同济医科大学附属同济医院

B超和同位素扫描系甲状腺疾病的辅助诊断方法,根据目前的知识和经验能作出很好的鉴别诊断。

关键词：甲状腺肿超声诊断同位素扫描

Factors Which Influence Intraluminal Temperature during Ho:YAG-Laser Exposure at an In-Vitro URS

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Open Journal of Urology 2015年第4期5卷 34-41页

作者： Jens cordes Felix Nguyen Karl-Dietrich Sievert Clinic of Urology University Medical Center Schleswig-Holstein Campus Lübeck Lübeck Germany

Introduction: The Ho:YAG-Laser is categorized as a potentially dangerous lithotripsy device (DIN: Class 4) for perforation which is mainly caused by the photonic energy the laser emits. Long time complications like ureteral strictures seem to be directed by thermal and mechanical injury. In this study different energy settings a) are being investigated, a DJ (double J stent) is placed beside the laser to simulate a therapy of a forgotten stent with reduction of the lumen b) due to the volume exploitation of the DJ, and direct contact between the laser fiber and the DJ in the ureter c) is simulated during laser exposure. materials and methods: We used the Ho:YAG-laser (Vera PulseTm, Coherent, Santa Clara USA) with a 365 μm diameter laser fiber. The settings of the laser were 0.6 J and 1 J pulse energy with a frequency of 5 Hz. The experimental setup was closely aligned with the clinical situation. The tip of the thermometer was attached inside the catheter through a puncture. The laser fiber was guided by means of a rigid URS video device (11.5 Ch). We had four different settings for a), b) and c) during the measurement: 1) Distance of 0.5 cm between the laser and the thermometer;without irrigation, 2) Distance of 0.5 cm between the laser and the thermometer;with irrigation, 3) Distance of 1 cm between the laser and the thermometer;without irrigation, 4) Distance of 1 cm between the laser and the thermometer;with irrigation. Results: The temperature in an empty ureter rises approximately by 5°C, when the laser energy is increased from 0.6 J to 1 J. When a DJ is inserted in the artificial ureter there is surprisingly almost no difference in the maximum temperature between the lower energy level (0.6 J) and the high energy level (1 J). However the time needed to reach the maximum temperature is noticibly less when using high energy levels. The reduction involume based on the placement of the DJ leads to a higher maximum temperature for the low energy setting. The third

关键词： YAG-Laser URS Laser Fiber DJ Ureteral

Statistical analyses for NANOGrav 5-year timing residuals

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Research in Astronomy and Astrophysics 2017年第2期17卷 63-76页

作者： Yan Wang James m. cordes Fredrick A. Jenet Shami Chatterjee Paul B. Demorest Timothy Dolch Justin A. Ellis michael T. Lam Dustin R. madison maura A. mcLaughlin Delphine Perrodin Joanna Rankin Xavier Siemens michele Vallisneri mOE Key Laboratory of Fundamental Physical Quantities measurements School of Physics Huazhong University of Science and Technology Wuhan 430074 China Center for Advanced Radio Astronomy University of Texas at Brownsville 1 West University Boulevard Brownsville TX 78520 USA Department of Physics and Astronomy University of Texas at Brownsville 1 West University Boulevard Brownsville TX 78520 USA Department of Astronomy Cornell University Ithaca NY 14853 USA National Radio Astronomy Observatory 520 Edgemont Road Charlottesville VA 22903 USA Department of Physics Hillsdale College 33 E. College Street Hillsdale M149242 USA Jet Propulsion Laboratory California Institute of Technology 4800 Oak Grove Drive Pasadena CA 91106 USA Department of Physics West Virginia University EO. Box 6315 Morgantown WV 26505 USA INAF-Osservatorio Astronomico di Cagliari Via della Scienza 5 09047 Selargius (CA) Italy Department of Physics University of Vermont Burlington VT 05405 USA Center for Gravitation Cosmology and Astrophysics Department of Physics University of Wisconsin-Milwaukee P.O. Box 413 Milwaukee WI 53201 USA

In pulsar timing, timing residuals are the differences between the observed times of arrival and predictions from the timing model. A comprehensive timing model will produce featureless resid- uals, which are presumably composed of dominating noise and weak physical effects excluded from the timing model （e.g. gravitational waves）. In order to apply optimal statistical methods for detecting weak gravitational wave signals, we need to know the statistical properties of noise components in the residuals. In this paper we utilize a variety of non-parametric statistical tests to analyze the whiteness and Gaussianity of the North American Nanohertz Observatory for Gravitational Waves （NANOGrav） 5- year timing data, which are obtained from Arecibo Observatory and Green Bank Telescope from 2005 to 2010. We find that most of the data are consistent with white noise; many data deviate from Gaussianity at different levels, nevertheless, removing outliers in some pulsars will mitigate the deviations.

关键词： pulsar timing array general -- statistical tests