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Hybrid-Vlasov simulation of soft X-ray emissions at the Earth’s dayside magnetospheric boundaries

Earth and Planetary Physics 2024年第1期8卷 70-88页

作者： M.Grandin H.K.Connor S.Hoilijoki M.Battarbee Y.Pfau-Kempf U.Ganse K.Papadakis M.Palmroth Department of Physics University of HelsinkiHelsinkiFinland NASA Goddard Space Flight Center GreenbeltMD20771USA Space and Earth Observation Centre Finnish Meteorological InstituteHelsinkiFinland

Solar wind charge exchange produces emissions in the soft X-ray energy range which can enable the study of near-Earth space regions such as the magnetopause,the magnetosheath and the polar cusps by remote sensing *** Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)and Lunar Environment heliospheric X-ray Imager(LEXI)missions aim to obtain soft Xray images of near-Earth space thanks to their Soft X-ray Imager(SXI)*** earlier modeling works have already simulated soft X-ray images as might be obtained by SMILE SXI during its mission,the numerical models used so far are all based on the magnetohydrodynamics description of the space *** investigate the possible signatures of ion-kinetic-scale processes in soft Xray images,we use for the first time a global hybrid-Vlasov simulation of the geospace from the Vlasiator *** simulation is driven by fast and tenuous solar wind conditions and purely southward interplanetary magnetic *** first produce global X-ray images of the dayside near-Earth space by placing a virtual imaging satellite at two different locations,providing meridional and equatorial *** then analyze regional features present in the images and show that they correspond to signatures in soft X-ray emissions of mirrormode wave structures in the magnetosheath and flux transfer events(FTEs)at the *** results suggest that,although the time scales associated with the motion of those transient phenomena will likely be significantly smaller than the integration time of the SMILE and LEXI imagers,mirror-mode structures and FTEs can cumulatively produce detectable signatures in the soft X-ray *** instance,a local increase by 30%in the proton density at the dayside magnetopause resulting from the transit of multiple FTEs leads to a 12%enhancement in the line-of-sight-and time-integrated soft X-ray emissivity originating from this ***,a proton density increase by 14%in the magnetosheath

关键词： magnetosphere magnetosheath numerical simulation SMILE LEXI soft X-ray emissions hybrid-Vlasov model polar cusp flux transfer events mirror-mode waves

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Do multiparous women need to work or exercise extra hard to control gestational diabetes?

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Journal of Sport and Health Science 2022年第5期11卷 550-551页

作者： Niina Matikainen Seppo Meri Endocrinology Abdominal CenterHelsinki University Hospital and University of HelsinkiFIN-00029 HUSHelsinkiFinland Department of Bacteriology and Immunology and Translational Immunology Research program University of HelsinkiFIN-00014HelsinkiFinland hus Diagnostic Center HUSLABHelsinki University HospitalFIN-00029 HUSHelsinkiFinland

In the current issue of the Journal of Sport and Health Science,Wang et al.^(1)describe their prospective study,where they analyzed whether or not multiple pregnancies would influence glycemia and the glycemic response to physical exercise in gestational diabetes mellitus(GDM).2 Multiparous women are known to be at a higher risk for GDM than *** carries an increased risk for adverse perinatal outcomes,not only for the mothers but also for the newborn *** to a contemporary environment that is conducive to a sedentary lifestyle and obesity,the incidence of GDM among pregnant women is increasing.

关键词： mother diabetes

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Deformations at Earth’s dayside magnetopause during quasi-radial IMF conditions:Global kinetic simulations and Soft X-ray imaging

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Earth and Planetary Physics 2024年第1期8卷 59-69页

作者： ZhongWei Yang RiKu Jarvinen XiaoCheng Guo TianRan Sun Dimitra Koutroumpa George K.Parks Can Huang BinBin Tang QuanMing Lu Chi Wang State Key Laboratory of Space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190China Finnish Meteorological Institute FI-00101 HelsinkiFinland LATMOS/IPSL CNRSUVSQ UniversitéParis-SaclaySorbonne UniversitéGuyancourt78280France Space Sciences Laboratory University of CaliforniaBerkeleyCalifornia 94720USA CAS Engineering Laboratory for Deep Resources Equipment and Technology Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029 China Deep Space Exploration Laboratory/School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China

The Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)is a joint mission of the European Space Agency(ESA)and the Chinese Academy of Sciences(CAS).Primary goals are investigating the dynamic response of the Earth's magnetosphere to the solar wind(SW)impact via simultaneous in situ magnetosheath plasma and magnetic field measurements,X-Ray images of the magnetosheath and magnetic cusps,and UV images of global auroral *** deformations associated with magnetosheath high speed jets(HSJs)under a quasi-parallel interplanetary magnetic field condition are studied using a threedimensional(3-D)global hybrid *** X-ray intensity calculated based on both physical quantities of solar wind proton and oxygen ions is *** obtain key findings concerning deformations at the magnetopause:(1)Magnetopause deformations are highly coherent with the magnetosheath HSJs generated at the quasi-parallel region of the bow shock,(2)X-ray intensities estimated using solar wind h+and self-consistentO7+ions are consistent with each other,(3)Visual spacecraft are employed to check the discrimination ability for capturing magnetopause deformations on Lunar and polar orbits,*** SMILE spacecraft on the polar orbit could be expected to provide opportunities for capturing the global geometry of the magnetopause in the equatorial plane.A striking point is that SMILE has the potential to capture small-scale magnetopause deformations and magnetosheath transients,such as HSJs,at medium altitudes on its *** results also demonstrate that a lunar based imager(e.g.,Lunar Environment heliospheric X-ray Imager,LEXI)is expected to observe a localized brightening of the magnetosheath during HSJ events in the meridian *** preliminary results might contribute to the pre-studies for the SMILE and LEXI missions by providing qualitative and quantitative soft X-ray estimates of dayside kinetic processes.

关键词： collisionless shock SMILE mission foreshock

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Global research landscape of Peutz-Jeghers syndrome and successful endoscopic management of intestinal intussusception in patients with recurrent laparotomies

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World Journal of Gastrointestinal Surgery 2024年第8期16卷 2702-2718页

作者： Qi Sun Xiao-Ying Wang Guang-Jin Guo Lei Wang Li-Min Meng Yun-Fei Guo Tao Sun Shou-Bin Ning Department of Gastroenterology Air Force Medical CenterBeijing 100142China College of Life Science Northwest UniversityXi'an 710069Shaanxi ProvinceChina Clinical Medical Laboratory Air Force Medical CenterBeijing 100142China Department of Medical imaging Air Force Medical CenterBeijing 100142China Department of Pathology Air Force Medical CenterBeijing 100142China

BACKGROUND Peutz-Jeghers syndrome(PJS)has brought significant physical,psychological and economic burdens on the patients and their families due to its early onset,diagnostic and therapeutic challenges and increased recurrence *** To explore the current research status and emerging hotspots of *** Studies on PJS published during 1994-2023 were gathered based on Web of Science Core ***,a case of PJS-induced intestinal intussusception,successfully treated with endoscopic methods despite three laparotomies,was *** bibliometric and visual analysis were conducted with VOSviewer,R and *** Altogether 1760 studies were identified,indicating a steady increase in the publication *** United States had the highest influence,whereas the university of helsinki emerged as the leading institution,and Aaltonen LA from the university of helsinki was the most prolific *** Research,Oncogene and Endoscopy were the top three journals based on *** burst direction analysis revealed that"cancer risk","management","surveillance"and"familial pancreatic cancer"were the potential hotspots for ***,"early detection","capsule endoscopy","clinical management","double-balloon endoscopy","familial pancreatic cancer"and"molecular genetic basis"were identified as the key clusters of co-cited *** polypectomy remained effective on resolving intestinal intussusception in patients who underwent three previous *** In the last three decades,global publications related to PJS show a steadily increasing trend in *** management is currently a research hotspot.

关键词： Peutz-Jeghers syndrome Endoscopy Management Cancer Microbiota Bibliometric

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Manipulation of space charge in silicon by intentional thermal donor activation

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中国有色金属学会会刊：英文版 2006年第A02期16卷 236-239页

作者： E. TUOVINEN J. HARKONEN P. LUUKKA E. TUOMINEN helsinki Institute of Physics University of Helsinki Finland 00014

A quantitative study about the thermal activation of thermal donors (TD) in high resistivity magnetic Czochralski (MCz) silicon was carried out. The samples are p+/p/n+ diodes (active area 0.25 cm2, thickness 300 μm) made of MCz p-type Si wafers with the resistivity of about 2 kΩ·cm. The concentration of interstitial oxygen (Oi) in this material was measured by the Fourier transformation infrared (FTIR) spectroscopy method and it is 4.9 × 1017 cm-3. The TD activation was performed through an isochronal thermal treatment at 430°C up to a total time of 120 min. The space charge density after each annealing step was extracted from capacitance-voltage (CV) measurements. The TD generation can be utilized in processing of silicon detectors (pixel, strip and drift detectors) that are used e.g. in space applications, high-energy physics experiments, and several visual imaging applications. If the starting material is boron-doped p-type high-resistivity Cz-Si, the TD generation process can be utilized in order to produce p+/n-/n+ detectors. The last thermal process step, i.e. the sintering of aluminum, is intentionally carried out at the temperature where TD's are created. Due to the generated donors, the p-type bulk will eventually be compensated to n-type bulk. Moreover, the full depletion voltage of detectors (Vfd) could be tailored between a wide range from 30 V up to almost 1000 V by changing heat treatment duration at 400-450°C from 20 to 120 min.

关键词：热供体硅半导体粒子探测器电子活性缺陷空间电荷

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Low trypsinogen-1 expression in pediatric ulcerative colitis patients who undergo surgery

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World Journal of Gastroenterology 2013年第21期19卷 3272-3280页

作者： Maija Piekkala Jaana Hagstrm Maarit Tanskanen Risto Rintala Caj Haglund Kaija-Leena Kolho Children's Hospital University of HelsinkiFIN-00029 HUSHelsinkiFinland Department of Pathology Haartman InstituteUniversity of HelsinkiFIN-00029 HUS HelsinkiFinland Department of Surgery Helsinki University Central HospitalFIN-00029 HUS HelsinkiFinland

AIM: To investigate whether matrix metalloproteinases-9 (MMP-9) or trypsinogens could serve as histological markers for an aggressive disease course in pediatric ulcerative colitis (UC). METHODS: We identified 24 patients with pediatric onset (≤ 16 years) UC who had undergone surgery during childhood/adolescence a median of 2.1 years (range 0.1-7.4 years) after the diagnosis (between 1990 and 2008) in Children's Hospital, helsinki, Finland. We also identified 27 conservatively treated UC patients and matched them based on their age at the time of diagnosis and follow-up at a median of 6 years (range 3-11 years) to serve as disease controls. Twenty children for whom inflammatory bowel disease (IBD) had been excluded as a result of endoscopy served as non-IBD controls. Colon biopsies taken by diagnostic endoscopy before the onset of therapy were stained using immunohistochemistry to study the expression of MMP-9, trypsinogen-1 (Tryp-1), Tryp-2, and a trypsin inhibitor (TATI). The profiles of these proteases and inhibitor at diagnosis were compared between the surgery group, the conservatively treated UC patients and the non-IBD controls. RESULTS: The proportions of Tryp-1 and Tryp-2 positive samples in the colon epithelium and in the inflammatory cells of the colon stroma were comparable between the studied groups at diagnosis. Interestingly, the immunopositivity of Tryp-1 (median 1; range 0-3) was significantly lower in the epithelium of the colon in the pediatric UC patients undergoing surgery when compared to that of the conservatively treated UC patients (median 2; range 0-3; P = 0.03) and non-IBD controls (median 2; range 0-3; P = 0.04). For Tryp-2, there was no such difference. In the inflammatory cells of the colon stroma, the immunopositivities of Tryp-1 and Tryp-2 were comparable between the studied groups at diagnosis. Also, the proportion of samples positive for TATI, as well as the immunopositivity, was comparable between the studied groups in the colon ep

关键词： Children Ulcerative colitis Inflammatory bowel disease Matrix metalloproteinase-9 resection Trypsin inhibitor

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Inhibition and enhancement of neural regeneration by chondroitin sulfate proteoglycans

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Neural Regeneration Research 2017年第5期12卷 687-691页

作者： Heikki Rauvala Mikhail Paveliev Juha Kuja-Panula Natalia Kulesskaya Neuroscience Center University of Helsinki Helsinki Finland Department of Biological and Environmental Sciences University of Helsinki Helsinki Finland

The current dogma in neural regeneration research implies that chondroitin sulfate proteoglycans（CSPGs） inhibit plasticity and regeneration in the adult central nervous system（CNS）. We argue that the role of the CSPGs can be reversed from inhibition to activation by developmentally expressed CSPG-binding factors. Heparin-binding growth-associated molecule（HB-GAM; also designated as pleiotrophin） has been studied as a candidate molecule that might modulate the role of CSPG matrices in plasticity and regeneration. Studies in vitro show that in the presence of soluble HB-GAM chondroitin sulfate（CS） chains of CSPGs display an enhancing effect on neurite outgrowth. Based on the in vitro studies, we suggest a model according to which the HB-GAM/CS complex binds to the neuron surface receptor glypican-2, which induces neurite growth. Furthermore, HB-GAM masks the CS binding sites of the neurite outgrowth inhibiting receptor protein tyrosine phosphatase sigma（PTPσ）, which may contribute to the HB-GAM-induced regenerative effect. In vivo studies using two-photon imaging after local HB-GAM injection into prick-injury of the cerebral cortex reveal regeneration of dendrites that has not been previously demonstrated after injuries of the mammalian nervous system. In the spinal cord, two-photon imaging displays HB-GAM-induced axonal regeneration. Studies on the HB-GAM/CS mechanism in vitro and in vivo are expected to pave the way for drug development for injuries of brain and spinal cord.

关键词： CNS injury axon regeneration dendrite regeneration proteoglycans aggrecan glypican HB-GAM pleiotrophin PTEN

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Poor Reproducibility in the Evaluation of Paranasal Sinus X-Rays in Chronic Rhinosinusitis

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Open Journal of Radiology 2017年第1期7卷 23-34页

作者： A. Luukkainen E. Terna J. Numminen A. Markkola P. Dastidar J. Jarnstedt H. Huhtala M. Karjalainen K. Blomgren P. Kauppi M. Rautiainen S. Toppila-Salmi Transplantation Laboratory Haartman Institute University of Helsinki Helsinki Finland Department of Otolaryngology Yong Loo Lin School of Medicine National University of Singapore Singapore Department of Ear and Oral Diseases Tampere University Hospital Tampere Finland university of helsinki and hus imaging Helsinki Finland Medical imaging Centre Department of Radiology Tampere University Hospital Tampere Finland School of Health Sciences University of Tampere Tampere Finland Department of Otorhinolaryngology University of Helsinki and Helsinki University Hospital Helsinki Finland Department of Allergy University of Helsinki and Helsinki University Hospital Helsinki Finland Department of Otorhinolaryngology University of Tampere Tampere Finland

Objective: The aim of this study was to evaluate intra- and inter-observer reproducibility of sinus x-rays in comparison to sinus computed tomography (CT) in chronic rhinosinusitis (CRS) patients. Methods: This was a prospective controlled study for which 14 adult CRS patients were recruited. Patients underwent a sinus multi-detector CT scan as well as additional sinus x-rays at the same time. Symptom interview and skin prick tests were performed. Lund-Mackay (LM) scores and 43 other findings in paranasal sinuses were analyzed by three blinded observers from CT-scans and x-rays. We compared agreement between sinus CT and x-rays (intra-observer reproducibility) and between three observers (inter-observer reproducibility) by Cohen’s kappa. Results: In at least 90% of the cases, the status of 47/49 structures was detectable in CT scans, whereas the status of only 8/49 structures was detectable in x-rays. The majority of the 25 visualized structures had poor intra-observer and inter-observer reproducibility. Conclusion: Only a few structures can be visualized in paranasal sinus x-rays and compared to paranasal sinus CT-scans, their reproducibility is poor. Our results strongly support the current consensus of radiation dose reduction by limiting the number of x-rays.

关键词： Sinusitis Paranasal Sinus Computed Tomography Magnetic Resonance imaging X-Ray

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Reproducibility of 3 mm-Slice-Thick Reconstruction of Paranasal Sinus Computed Tomography Scans

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Open Journal of Radiology 2016年第1期6卷 39-48页

作者： Matti Karjalainen Anna Julkunen Antti Markkola Prasun Dastidar Heini Huhtala Mikko Suvinen Anna-Maija Kuukka Markus Rautiainen Jura Numminen Sanna Toppila-Salmi Department of Otorhinolaryngology University of Tampere Tampere Finland Transplantation Laboratory Haartman Institute University of Helsinki Helsinki Finland Department of Oral and Maxillofacial Diseases University of Helsinki and Helsinki University Hospital Helsinki Finland university of helsinki and hus imaging Helsinki Finland Medical imaging Centre Department of Radiology Tampere University Hospital Finland School of Public Health University of Tampere Tampere Finland Department of Otorhinolaryngology Tampere City Hospital Tampere Finland Department of Ear and Oral diseases Tampere University Hospital Tampere Finland Department of Allergy University of Helsinki and Helsinki University Hospital Helsinki Finland

Background: After the failure of medical treatment, the surgery of chronic rhinosinusitis (CRS) is planned according to endoscopic and paranasal sinus computed tomography (CT) findings. Objective: The aim of this prospective study was to evaluate whether this study method might be eligible in studies aiming at radiation dose reduction. Sinus CT scans were chosen as a model because of the high variation of the radiological anatomy of surgically important sinonasal structures. We hypothesized that 3 mm-slice-thick reconstruction CT had poor reproducibility. Methods: 59 CRS patients underwent routine multi-detector sinus CT (CTMD). CT3mm was reconstructed from CTMD data-sets. Lund-Mackay (LM) scores and 43 other structural parameters were analyzed blinded. Agreement was studied between CTMD and CT3mm (intra-observer reproducibility), and between three observers (inter-observer reproducibility) by using Cohen’s kappa. Results: The inter-observer agreement was moderate (kappa 0.4 - 0.6, p 3mm scans. The intra-observer reproducibility of CT3mm scans was very good in most structures, however, it was poor in important structures such as frontal and spheno-ethmoid recess, lamina papyracae, and location of optic nerve or anterior ethmoidal artery. The grade of surgeon’s confidence of CT3mm in comparison to CTMD was lower (kappa 0.2 - 0.4, P < 0.05). Conclusion: This methodology might have some use in studies aiming at radiation dose reduction. As was expected, 3 mm-slice-thick reconstruction CT had poor reproducibility and surgeon’s confidence. More recent methods such as cone beam computed tomography scans have nowadays more relevant dose reduction potential.

关键词： Chronic Rhinosinusitis Computed Tomography Image Reconstruction Inter-Observer Agreement Intra-Observer Agreement Kappa Radiation-Dose Reduction Reproducibility Paranasal Sinus Sinus imaging

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患急性乳突炎和偶发性乳突T2WI高信号的儿童与成人病例的MRI的特征比较

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国际医学放射学杂志 2016年第5期 593-594页

作者： R.Saat G.Mahmood A.Laulajainen-Hongisto L.Lempinen A.A.Aarnisalo J.Jero 高国栋 Department of Radiology HUS Medical Imaging CentreHelsinki University Hospital and University of Helsinki

摘要目的本研究通过比较偶发性乳突T2WI高信号病人与临床确诊为急性乳突炎病人的MR影像表现,明确两者间特征性差异。方法对35例临床确诊急性乳突炎的成年及儿童病人,以及34例连续、偶然发现乳突50%以上T2高信号匹配的对照组病例,回顾性... 详细信息

摘要目的本研究通过比较偶发性乳突T2WI高信号病人与临床确诊为急性乳突炎病人的MR影像表现,明确两者间特征性差异。方法对35例临床确诊急性乳突炎的成年及儿童病人,以及34例连续、偶然发现乳突50%以上T2高信号匹配的对照组病例,回顾性分析两者乳突的信号,扩散及强

关键词：乳突病人乳头突颞骨急性乳突炎 T2WI 儿童偶发性病例 MRI

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