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Factors influencing the spinal motoneurons in development

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Neural Regeneration Research 2015年第11期10卷 1773-1776页

作者： stefan Wiese Faculty for Biology and Biotechnology Group for Molecular Cell Biology Universitaetsstr.150 Ruhr University Bochum

The development of the spinal cord needs a concerted interaction of transcription factors activating diverse genes and signals from outside acting on the specification of the different cells. Signals have to act on the segments of the embryo as well as on the cranial-caudal axis and the dorso-ventral axis. Additionally the axons of the motoneurons have to cross the central nervous system barrier to connect to the periphery. Intensive anatomical studies have been followed by molecular characterization of the different subsets of transcription factors that are expressed by cells of the developing spinal cord. Here, intensive studies for the most important appearing cells, the motoneurons, have resulted in a good knowledge on the expression patterns of these proteins. Nonetheless motoneurons are by far not the only important cells and the concert activity of all cells besides them is necessary for the correct function and integrity of motoneurons within the spinal cord. This article will briefly summarize the different aspects on spinal cord development and focuses on the differentiation as well as the functionalization of motoneurons.

关键词： axon neurite synapse muscle extracellular matrix transcription factors

Nanocrystalline rare earth fluorides doped with Pr^(3+) ions

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Journal of Rare Earths 2016年第8期34卷 802-807页

作者： Marcin Runowski stefan Lis department of Rare Earths Faculty of Chemistry Adam Mickiewicz University

Praseodymium（III） doped CeF3, CeF3：Gd, LaF3, GdF3 and YF3 inorganic fluorides were precipitated in an aqueous, sur- factant-free solution, using NH4F as a source of fluoride ions. The as-prepared products were subjected to a hydrothermal treatment, which led to the formation of crystalline nanoluminophores, composed of spherical （30 nm） and elongated （40-200 nm） nanos- tructures. due to the presence of Pr3＋ ions, the synthesized nanomaterials showed yellow luminescence under a blue light irradiation. The nanoluminophore based on the YF3 host revealed the most promising spectroscopic properties, i.e., bright and intensive emission, hence it was investigated in detail. The photophysical properties of the nanomaterials obtained were studied by powder X-ray diffrac- tion （XRd）, transmission electron microscopy （TEM） and spectrofluorometry, i.e., measurements of excitation/emission spectra and luminescence decay curves.

关键词： yellow luminescence lanthanide fluorides Pr3+ doping nanocrystals hydrothermal post-treatment Ce3+ quenching rare earths

Flexible Furnace Concepts for Vacuum Heat Treatment Combined with High-pressure Gas Quenching

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材料热处理学报 2004年第5期25卷 607-611页

作者： Karl killer stefan Wiebach ALd Vacuum Technologies AG Hanau - GermanyALD Vacuum Technologies AG Hanau - Germany

IN the past five years the process combination of vacuum hardening, respectively vacuum carburizing with high-pressure gas quenching was successfully introduced to the market, especially in the manufacture of gears. In the meantime furnace concepts for various applications are available to the industry. In the following report three plant varieties are introduced, which differ in process flexibility and throughput. This report also explains criteria for the selection of a furnace in view of the existing application requirements. Besides this a short introduction is given into the vacuum carburizing process and the high-pressure gas quenching technology.

关键词：真空热处理真空渗碳高压气体流淬火炉子

Photovoltaic yield prediction using an irradiance forecast model based on multiple neural networks

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Journal of Modern Power Systems and Clean Energy 2018年第2期6卷 255-267页

作者： Saad Parvaiz dURRANI stefan BALLUFF Lukas WURZER stefan KRAUTER Paderborn University Bosch Thermotechnik GmbH

In order to develop predictive control algorithms for efficient energy management and monitoring for residential grid connected photovoltaic systems, accurate and reliable photovoltaic(PV) power forecasts are required.A PV yield prediction system is presented based on an irradiance forecast model and a PV model. The PV power forecast is obtained from the irradiance forecast using the PV model. The proposed irradiance forecast model is based on multiple feed-forward neural networks. The global horizontal irradiance forecast has a mean absolute percentage error of 3.4% on a sunny day and 23% on a cloudy day for Stuttgart. PV power forecasts based on the neural network irradiance forecast have performed much better than the PV power persistence forecast model.

关键词： Grid connected photovoltaic(GCPV) Photovoltaic(PV) PV power prediction Irradiance forecast Neural network(NN)

Neutron diffraction studies on ‘‘simple'' iron oxides under pressure: Fe_3O_4, a-Fe_2O_3, and FeO

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Chinese Science Bulletin 2014年第36期59卷 5241-5250页

作者： stefan Klotz IMPMC CNRS UMR 7590 Universite' Pierre & Marie Curie75252 Paris France

Fe3O4(magnetite), a-Fe2O3(hematite), and Fe O(wu¨ stite) are the three major iron oxides and some of the most fundamental solids in nature. Interest in these systems is due to their abundance as minerals in the Earth and other telluric planets as well as their interesting electronic and magnetic properties which have been studied for decades. In this article, we review high-pressure studies on these three systems using neutron powder diffraction in the0–14 GPa range with a particular focus on the behavior of magnetism under pressure. Unpublished data on the pressure dependence of the Ne′el temperature in Fe O are presented. This review will give at the same time an introduction into technical aspects and illustrate the potential of high-pressure neutron scattering in the future.

关键词：四氧化三铁 α-氧化铁中子衍射 α-Fe2O3 磁压力 FeO 中子散射磁铁矿

Surgical management of peritonitis secondary to acute superior mesenteric artery occlusion

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World Journal of Gastroenterology 2014年第29期20卷 9936-9941页

作者： stefan Acosta Vascular Centre Malm?Sk?ne University Hospital

diagnosis of acute arterial mesenteric ischemia in the early stages is now possible using modern computed tomography with intravenous contrast enhancement and imaging in the arterial and/or portal *** patients have acute superior mesenteric artery(SMA)occlusion,and a large proportion of these patients will develop peritonitis prior to mesenteric revascularization,and explorative laparotomy will therefore be necessary to evaluate the extent and severity of intestinal ischemia,and to perform bowel *** establishment of a hybrid operating room in vascular units in hospitals is most important to be able to perform successful intestinal *** review outlines current frontline surgical strategies to improve survival and minimize bowel morbidity in patients with peritonitis secondary to acute SMA *** laparotomy needs to be performed *** treatment is based upon intestinal revascularization followed by bowel *** no vascular imaging has been carried out,SMA angiography is *** case of embolic occlusion of the SMA,open embolectomy is performed followed by *** case of thrombotic occlusion,the occlusive lesion can be recanalized retrograde from an exposed SMA,the guidewire snared from either the femoral or brachial artery,and stented with standard devices from these access *** resections and sometimes gall bladder removal due to transmural infarctions are performed at initial laparotomy,leaving definitive bowel reconstructions to a planned second look laparotomy,according to the principles of damage control *** with peritonitis secondary to acute SMA occlusion should be managed by both the general and vascular surgeon,and a hybrid revascularization approach is of utmost importance to improve outcomes.

关键词： Acute mesenteric ischemia Peritonitis Explorative laparotomy Endovascular treatment Hybrid revascularization Superior mesenteric artery occlusion

Galerkin Spectral Method Applied to the Chemical Master Equation

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Communications in Computational Physics 2009年第5期5卷 871-896页

作者： stefan Engblom department of Information Technology Uppsala UniversityP.O.Box 337SE-75105 UppsalaSweden

Stochastic well-stirred chemically reacting systems can be accurately modeled by a continuous-time *** corresponding master equation evolves the system’s probability density function in time but can only rarely be explicitly *** investigate a numerical solution strategy in the form of a spectral method with an inherent natural adaptivity and a very favorable choice of basis *** results related to convergence have been developed previously and are briefly summarized while implementation issues,including how to adapt the basis functions to follow the solution they represent,are covered in more detail *** method is first applied to a model problem where the convergence can easily be *** we take on two more realistic systems from molecular biology where stochastic descriptions are often necessary to explain experimental *** conclusion is that,for sufficient accuracy demands and not too high dimensionality,the method indeed provides an alternative to other methods.

关键词： Master equation spectral-Galerkin method high dimensional problem moving basis chemical reactions

Role of Omicron variant of SARS-CoV-2 in children in Germany

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World Journal of Pediatrics 2022年第4期18卷 283-284页

作者： stefan Bittmann department of Pediatrics Medical and Finance Center EpePed Mind Institute(PMI)Hindenburgring 448599 GronauGermany

A new variant of SARS-CoV-2,B.1.1.529 was first reported by the South African department of Health on Nov 24,*** new variant was named as B.1.1.529 Omicron and was classified as a variant of concern(VOC)by the World Health Organization(WHO)on Nov 26,2021[1-13],Phylogenetic studies showed that Omicron arose independently of the currently dominant delta *** has an unusually high number of approximately 30 changes of amino acids in the spike protein compared with the original SARS-CoV-2,including those with known phenotypic impact(increase in transmission,immune evasion,and transmissibility),but significances of many mutations are still unclear[4-7].

关键词： Omi Phylogenetic children

Current treatment options and response rates in children with chronic hepatitis C

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World Journal of Gastroenterology 2012年第2期18卷 99-104页

作者： stefan Wirth Helios Medical Centre Wuppertal Department of PediatricsWitten-Herdecke UniversityD-42283 WuppertalGermany

Vertical transmission has become the most common mode of transmission of hepatitis C virus (HCV) in *** rate of perinatal transmission from an HCVinfected mother to her child ranges from 2% to 5% and the prevalence of HCV in children in developed countries ranges between 0.1% and 0.4%.Spontaneous viral clearance seems to be dependent on the genotype and has been reported between 2.4%-25%.For chronically infected patients,treatment with recombinant polyethylene glycol (PEG)-interferon α-2b and daily ribavirin has now been approved as standard treatment for children 2-17 years of *** five large prospective studies,a total of 318 children and adolescents aged 3-17 years were treated either with subcutaneous PEG-interferon α-2b at a dose of 1-1.5 μg/kg or 60 μg/m2 once a week in combination with oral ribavirin (15 mg/kg per day) or PEG-interferon α-2a with *** with genotype 1 and 4 received the medication for 48 wk and individuals with genotype 2 and 3 mainly for 24 *** sustained viral response (SVR) was achieved in 193/318 (60.7%) of treated *** for genotype;120/234 (51%) with genotype 1,68/73 (93%) with genotype 2/3,and 6/11 (55%) with genotype 4 showed *** rate was between 7.7% and 17%.Overall,treatment was well tolerated;how-ever,notable side effects were present in approximately 20%.According to recent experiences in the treatment of chronic hepatitis C in children and adolescents,a combination of PEG-interferon α with ribavirin has been found to be well tolerated and highly efficacious,particularly in individuals with genotype 2/***,this treatment can be recommended as standard of care until more effective treatment options will become available for genotype 1 patients.

关键词： Chronic hepatitis C Treatment Children Polyethylene glycol-interferon and ribavirin Responserate