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The Galactic halo magnetic field revisited

Research in Astronomy and Astrophysics 2010年第12期10卷 1287-1297页

作者： wolfgang reich Max-Planck-Institut für Radioastronomie Auf dem Hügel 69 53121 Bonn Germany

Recently, Sun et al. published new Galactic 3D-models of magnetic fields in the disk and halo of the Milky Way and the distribution of cosmic-ray electron density by taking into account the thermal electron density model NE2001 by Cordes ＆ Lazio. The models successfully reproduce observed continuum and polarization all-sky maps and the distribution of rotation measures of extragalactic sources across the sky. However, the model parameters obtained for the Galactic halo, although reproducing the observations, seem physically unreasonable： the magnetic field needs to be significantly stronger in the Galactic halo than in the plane and the cosmic-ray distribution must be truncated at about 1 kpc to avoid excessive synchrotron emission from the halo. The reason for these unrealistic parameters was the low scale-height of the warm thermal gas of about 1 kpc adopted in the NE2001 model. However, this scale- height seemed reasonable and was well studied by numerous investigations. Recently, the scale-height of the warm gas in the Galaxy was revised by Gaensler et al. to about 1.8 kpc, by showing that the 1 kpc scale-height results from a systematic bias in the analysis of pulsar data. This implies a higher thermal electron density in the Galactic halo, which in turn reduces the halo magnetic field strength to account for the observed rotation measures of extragalactic sources. We slightly modified the NE2001 model according to the new scale-height and revised the Sun et al. model parameters accordingly： the strength of the regular halo magnetic field is now 2 μG or lower, and the physically unrealistic cutoff in z for the cosmic-ray electron density is removed. The simulations based on the revised 3D-models reproduce all-sky observations as before.

关键词： ISM: magnetic fields -- ISM: structure -- radio continuum: ISM

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Peering into the Milky Way by FAST:Ⅳ.Identification of two new Galactic supernova remnants G203.1+6.6and G206.7+5.9

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Science China(Physics,Mechanics & Astronomy) 2022年第12期65卷 55-67页

作者： XuYang Gao wolfgang reich XiaoHui Sun He Zhao Tao Hong ZhongSheng Yuan Patricia reich JinLin Han National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China Max-Planck-Institut fur Radioastronomie Bonn 53121Germany School of Physics and Astronomy Yunnan UniversityKunming 650500China Purple Mountain Observatory Chinese Academy of SciencesNanjing 210023China School of Astronomy University of Chinese Academy of SciencesBeijing 100049China

A 5°×7°sky area containing two large radio structures of G203.1+6.6 and G206.7+5.9 with a size of about 2.°5 and 3.°5 respectively is scanned by using the L-band 19-beam receiver of the Five-hundred-meter Aperture Spherical radio Telescope(FAST).The FAST L-band receiver covers a frequency range of 1.0-1.5 *** of the receiving system,including the measurements of the half-power beam width,gain,and main-beam efficiency is made by observing the *** multi-channel spectroscopy backend mounted to the receiver allows an in-band spectral-index *** brightness-temperature spectral indices of both objects are measured to beβ~-2.6 *** emission is detected from the archival Effelsbergλ11 cm data for all the shell structures of G203.1+6.6 and G206.7+*** results clearly indicate a non-thermal synchrotron emitting nature,confirming that G203.1+6.6 and G206.7+5.9 are large shell-type supernova remnants(SNRs).Based on morphological correlation between the radio continuum emission of G206.7+5.9 and the H i structures,the kinematic distance to this new SNR is estimated to be about 440 pc,placing it in the Local Arm.

关键词： supernova remnants interstellar medium magnetic fields polarization

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Towards engineering a portable platform for laparoscopic pre-training in virtual reality with haptic feedback

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虚拟现实与智能硬件（中英文） 2024年第2期6卷 83-99页

作者： Hans-Georg ENKLER wolfgang KUNERT Stefan PFEFFER Kai-Jonas BOCK Steffen AXT Jonas JOHANNINK Christoph reich Furtwangen University 78120 FurtwangenGermany University Hospital and Faculty of Medicine Tuebingen 72076 TuebingenGermany

Background Laparoscopic surgery is a surgical technique in which special instruments are inserted through small incision holes inside the *** some time,efforts have been made to improve surgical pre training through practical exercises on abstracted and reduced *** The authors strive for a portable,easy to use and cost-effective Virtual Reality-based(VR)laparoscopic pre-training platform and therefore address the question of how such a system has to be designed to achieve the quality of today's gold standard using real tissue *** VR controllers are limited regarding haptic *** haptic feedback is necessary or at least beneficial for laparoscopic surgery training,the platform to be developed consists of a newly designed prototype laparoscopic VR controller with haptic feedback,a commercially available head-mounted display,a VR environment for simulating a laparoscopic surgery,and a training *** To take full advantage of benefits such as repeatability and cost-effectiveness of VR-based training,the system shall not require a tissue sample for haptic *** is currently calculated and visually displayed to the user in the VR *** the prototype controller,a first axis was provided with perceptible feedback for test *** of the prototype VR controllers can be combined to simulate a typical both-handed use case,e.g.,laparoscopic suturing.A Unity based VR prototype allows the execution of simple standard *** The first prototype enables full operation of a virtual laparoscopic instrument in *** addition,the simulation can compute simple interaction *** challenges lie in a realistic real-time tissue simulation and calculation of forces for the haptic *** weaknesses were identified in the first hardware prototype,which will be improved in subsequent *** degrees of freedom of the controller are to be provided with haptic *** make forces t

关键词： Laparoscopic surgery Training Virtual reality Controller Haptic feedback Kinesthetic skills

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A polarization study of the supernova remnant CTB 80

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Research in Astronomy and Astrophysics 2020年第11期20卷 312-320页

作者：李向华孙晓辉 wolfgang reich 高旭阳 Department of Astronomy Yunnan Universityand Key Laboratory of Astroparticle Physics of Yunnan ProvinceKunming 650091China Max-Planck-Institut fur Radioastronomie Auf dem Hugel 6953121 BonnGermany National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China CAS Key Laboratory of FAST National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China

We present a radio polarization study of the supernova remnant CTB 80 based on images at1420 MHz from the Canadian Galactic Plane Survey,at 2695 MHz from the Effelsberg survey of the Galactic plane and at 4800 MHz from the Sino-Germanλ6 cm polarization survey of the Galactic *** obtained a rotation measure(RM)map using polarization angles at 2695 MHz and 4800 MHz as the polarization percentages are similar at these two *** exhibits a transition from positive values to negative values along one of the shells hosting the pulsar PSR B1951+32 and its pulsar wind *** reason for the change in sign remains *** identified a partial shell structure,which is bright in polarized intensity but weak in total *** structure could be part of CTB 80 or part of a new supernova remnant unrelated to CTB 80.

关键词： ISM supernova remnants ISM magnetic fields polarization techniques polarimetric

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New continuum and polarization observations of the Cygnus Loop with FAST *** processing and verification

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Research in Astronomy and Astrophysics 2021年第11期21卷 105-118页

作者：孙晓辉蒙美娘高旭阳 wolfgang reich 姜鹏李菂闫慧荣李向华 Department of Astronomy Yunnan UniversityKunming 650500China National Astronomical Observatories Chinese Academy of Sciences20A Datun RoadChaoyang DistrictBeijing 100101China CAS Key Laboratory of FAST National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China Max-Planck-Institut fur Radioastronomie Auf dem Hugel 6953121 BonnGermany Deutsches Elektronen-Synchrotron DESY Platanenallee 6D-15738 ZeuthenGermany Institut fur Physik und Astronomie Universitat PotsdamHaus 28Karl-Liebknecht-Str.24/25D-14476 PotsdamGermany

We report on the continuum and polarization observations of the Cygnus Loop supernova remnant(SNR)conducted by the Five-hundred-meter Aperture Spherical radio Telescope(FAST).FAST observations provide high angular resolution and high sensitivity images of the SNR,which will help to disentangle its *** obtained Stokes I,Q and U maps over the frequency range of 1.03-1.46 GHz split into channels of 7.63 *** original angular resolution is in the range of~3’-~3.’8,and we combined all the data at a common resolution of 4’.The temperature scale of the total intensity and the spectral index from the in-band temperature-temperature plot are consistent with previous observations,which validates the data calibration and map-making *** rms sensitivity for the band-averaged total-intensity map is about 20 mK in brightness temperature,which is at the level of confusion *** the first time,we apply rotation measure(RM)synthesis to the Cygnus Loop to obtain the polarization intensity and RM *** rms sensitivity for polarization is about 5 mK,far below the total-intensity confusion *** also obtained RMs of eight extragalactic sources,and demonstrate that the wide-band frequency coverage helps to overcome the ambiguity of RM determinations.

关键词： ISM:supernova remnants ISM:magnetic fields polarization techniques:polarimetric

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Polarised radio emission associated with HESS J1912+101

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Research in Astronomy and Astrophysics 2019年第3期19卷 123-130页

作者： wolfgang reich Xiao-Hui Sun Max-Planck-Institut für Radioastronomie Department of Astronomy Yunnan Universityand Key Laboratory of Astroparticle Physics of Yunnan Province

The shell-type TeV source HESS J1912+101 was tentatively identified as an old supernova remnant, but is missing counterparts at radio and other frequencies. We analysed the Sino-German Urumqiλ6 cm survey and the Effelsberg λ11 cm and λ21 cm surveys to identify radio emission from HESS J1912+101 to clarify the question of a supernova origin. We find a partial shell of excessive polarisation at λ6 cm at the periphery of HESS J1912+101. At λ11 cm, its polarised emission is faint and suffers from depolarisation, while at λ21 cm, no related polarisation is seen. We could not separate the shell's total intensity signal from the confusing intense diffuse emission from the inner Galactic plane. However, a high percentage of polarisation in the shell's synchrotron emission is indicated. Our results support earlier suggestions that HESS J1912+101 is an old supernova remnant. The synchrotron emission is highly polarised,which is typical for evolved supernova remnants with low surface brightness.

关键词： radio continuum ISM-ISM individual objects HESS J1912+101-ISM magnetic fields

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Non-linear dynamic state-space network modeling for decoding neurodegeneration

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Neural Regeneration Research 2024年第9期19卷 1879-1880页

作者： Venkata C.Chirumamilla Chi Wang Ip Martin reich Robert Peach Jens Volkmann Bahman Nasseroleslami Muthuraman Muthuraman Prenatal Pediatrics Institute Children’s National HospitalWashingtonDCUSA Neural Engineering with Signal Analytics and Artificial Intelligence Department of NeurologyUniversity of WürzburgWürzburgGermany Academic Unit of Neurology Trinity Biomedical Sciences InstituteTrinity College DublinUniversity of DublinDublinIreland

Neurodegenerative disorders represent a pervasive global health challenge,yet therapeutic options remain conspicuously *** disorders are inherently dynamic processes within the central nervous system,unfolding across distinct sub-stages:initial structural neuronal alterations(sub-stage 1),functional impairment(sub-stage 2),and culminating in neuronal death(sub-stage 3).

关键词： alterations impairment dynamic

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EVA NEXUS-Phaco performance study

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International Journal of Ophthalmology(English edition) 2024年第8期17卷 1447-1452页

作者： Lukas Feldhaus Andreas Ohlmann Stefan Kassumeh Siegfried Priglinger wolfgang Mayer Department of Ophthalmology University HospitalLudwig-Maximilians-University MunichMunich 80336Germany

AIM:To investigate a novel phacoemulsification system“EVA NEXUS”(D.O.R.C.,Dutch Opthalmic Research Center)in comparison to the existing system“EVA”in clinical *** to compare both phacoemulsification systems in terms of efficiency,safety and postoperative inflammatory ***:In this study standardized cataract surgery was performed on both eyes of the study participant,using the“EVA system”(control group,n=20)on one eye and the“EVA NEXUS system”(intervention group,n=20)on the other *** patients with cataract LOCS Grading 1-3 and no accompanying eye diseases were included in this study.A total of 20 patients were included in this study,with each treatment arm including 20 *** surgery a 0.1 mL aqueous humor sample was collected 1min after phacoemulsification to measure the total prostaglanin E2 concentrations using an enzyme-linked immunosorbent *** endothelial cell count,visual and refractive outcomes,and anterior chamber flare were evaluated preoperatively,and 1d,1wk,and 3mo ***:There were no statistically significant differences between both groups regarding intraoperative safety parameters including effective phacoemulsification time(P=0.904),balanced saline solution flow(P=0.701)and total surgery time(P=0.565).Postoperative prostaglandin E2 levels,anterior chamber flare as well as endothelial cell loss tended to be lower in the NEXUS-Group,however not being statistically significant(P=0.718;0.164;0.486).Both systems provided similar clinical outcomes,regarding best corrected visual acuity and refractive parameters,showing no statistically significant differences between both ***:Both systems show a high level of safety and efficency with similar results in terms of safety parameters including postoperative inflammatory activity and endothelial cell loss as well as visual and refractive *** statistically not significant,the EVA NEXUS system tends to cause less postoperative inflammatio

关键词： cataract surgery phacoemulsification fluidics instrument

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V0644 Ser:An Active Ultrashort Period Contact Binary Star

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Research in Astronomy and Astrophysics 2022年第12期22卷 252-262页

作者： Hu-Shan Xu Li-Ying Zhu Sarotsakulchai Thawicharat Soonthornthum Boonrucksar Yunnan Observatories Chinese Academy of Sciences(CAS)Kunming 650216China University of the Chinese Academy of Sciences Beijing 100049China Key Laboratory of the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650216China National Astronomical Research Institute of Thailand 191 Siriphanich Bldg.Huay Kaew Rd.Chiang Mai 50200Thailand

The photometric solutions of the ultrashort period close binary V0644 Ser based on our new complete BVRI light curves are derived by the Wilson–Devininney *** results show that V0644 Ser is a W-type shallow contact binary,and the third light was found in the R and I *** with the light curves in 2011,the amplitude variation of the secondary maximum can be explained by the temperature change from hot to cold in the local region of the star surface caused by magnetic activity or convective *** with the Gaia parallax,the absolute parameters of this system are obtained:M_(1)=0.29(4)M_(⊙),R_(1)=0.48(3)R_(⊙),R_(2)=0.65(3)R_(⊙),L_(1)=0.11(2)L_(⊙),L_(2)=0.16(2)L_(⊙)=0.16(2)L_(⊙).To study the period variation,we fitted the Super WASP,CSS,ASAS-SN and ZTF survey timing data to obtain light minima times spanning 14 *** O-C analysis,we find that the orbital period of this system has a long-term period decrease and periodic *** long-term period decrease can be explained by the mass transfer from more-massive component to less one and angular momentum loss via magnetic stellar *** the period decrease,this system is evolving from the present shallow contact phase to a relatively deeper stage predicted by the thermal relaxation oscillation *** oscillation can be explained by the light-time effect of the cool third *** third body may play an important role in the early formation and evolution of the binary system by removing angular momentum.

关键词： (stars:)binaries(including multiple):close (stars:)binaries:eclipsing stars:late-type stars:individual(V0644 Ser)

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Going deep:Roots,carbon,and analyzing subsoil carbon dynamics

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Molecular Plant 2024年第1期17卷 1-3页

作者： Ezhilmathi Angela Joseph Fernando Michael Selvaraj Yusaku Uga wolfgang Busch Hunt Bowers Joe Tohme Alliance of Bioversity International and CIAT Km 17 Recta Cali-PalmiraAprtado Aereo 6713Cali 763537Colombia National Institute of Agrobiological Sciences(NIAS) TsukubaIbaraki 305-0856Japan Salk Institute for Biological Studies 10010 N Torrey Pines RoadLa JollaCA 92037USA Earth Optics Suite 840ArlingtonVA 22202USA

Agricultural practices currently contribute to the emission of approximately 10%–12%atmospheric greenhouse gasses,with tillage agriculture accelerating soil disruption and carbon dioxide ***,various options exist,such as converting new lands for agriculture,promoting healthier plant-based diets,adopting advanced management technologies,and minimizing food ***,these measures alone are insufficient to ensure environmental sustainability within planetary boundaries.

关键词： soil measures carbon

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