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RELAXATION SOLVERS FOR IDEAL MHD EQUATIONS-A REVIEW

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Acta Mathematica Scientia 2010年第2期30卷 621-632页

作者： christian Klingenb.rg Knut Waagan Departement of Mathematics Würzburg University The University of Maryland CSCAMM4146 CSIC Building#406 Paint Branch DriveCollege Park MD 20742-3289USA

We have developed approximate Riemann solvers for ideal MHD equations b.sed on a relaxation approach in [4], [5]. These lead to entropy consistent solutions with good properties like guaranteed positive density. We describ. the extension to higher order and multiple space dimensions. Finally we show our implementation of all this into the astrophysics code FLASH.

关键词： conservation laws ideal magnetohydrodynamics finite volume schemes en-tropy stab.e schemes positive schemes

寒武纪软舌螺壳体形态解剖研究与冠轮动物演化

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科学通报 2021年第27期66卷 3631-3644页

作者：刘璠张志飞 christian b.Skovsted 西北大学地质学系大陆动力学国家重点实验室陕西省早期生命与环境重点实验室西安710069 Department of Palaeob.ology Swedish Museum of Natural HistoryStockholm SE-10405Sweden

软舌螺是一类寒武纪出现并于二叠纪末灭绝的古生代海生无脊椎动物,具有重要的地层划分与对比意义.但是对于该动物本身生物属性等问题一直莫衷一是,近年中国寒武纪早期的特异型埋藏化石库中发现了大量保存软躯体的珍稀软舌螺动物化石.结... 详细信息

软舌螺是一类寒武纪出现并于二叠纪末灭绝的古生代海生无脊椎动物,具有重要的地层划分与对比意义.但是对于该动物本身生物属性等问题一直莫衷一是,近年中国寒武纪早期的特异型埋藏化石库中发现了大量保存软躯体的珍稀软舌螺动物化石.结合华南、华北同期碳酸盐岩沉积地层中的壳体化石,系列报道将软舌螺的化石生物学、壳体矿化和分类系统学研究推到新的高度,为探讨寒武纪大爆发壳体动物的演化,尤其是冠轮动物的系统学提供新的化石证据.澄江动物群的直管螺目三槽螺属化石发现保存有粗大的扇状触手器官,其基部可以在壳体内自由伸缩,与触手基部固定的触手冠动物明显不同,表明软舌螺与触手冠动物具有不同的生理结构和取食机制.综合最新微细结构的发现,支持软舌螺是一类与软体动物关系紧密的冠轮动物.软舌螺新材料的研究对寒武纪大爆发后生动物的演化提出了新的科学问题:后生动物在矿化体制发生演化中到底是整个壳体出现早,还是多骨片的骨骼系出现早——即形态上完整的生物壳体是由多个骨片愈合而成,还是反之.如何将矿化的整壳和骨片系与壳体内部组织器官和显微结构进行有效的极向系统分析,是未来冠轮动物进化生物学和古生物系统学研究的共同挑战.

关键词：软舌螺寒武纪壳体结构解剖学摄食器官消化道

Understanding Genetic Load in Potato for Hyb.id Diploid b.eeding

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Molecular Plant 2019年第7期12卷 896-898页

作者： christian W.b.b.chem Herman J.van Eck Michiel E.de Vries Plant b.eeding Wageningen University and Research Wageningen the Netherlands Solynta Wageningen the Netherlands

Recently, Zhang et al.(2019) have managed to provide ab.ndant evidence to support long-held theories regarding mechanisms of inb.eeding depression and potential effects of heterosis that are likely to have a considerab.e impact on potato b.eeding in the future (Figure 1). Despite its large genetic variation regarding yield, harvest index, and water use efficiency, potato b.eeding has attained only negligib.e advances in the most important b.eeding goals such as yield, tub.r quality, and ab.otic stress tolerance, and only modest progress in pathogen resistance. This low level of improvement is clearly due to the complexity of b.eeding a heterozygous tetraploid outb.eeder rather than to the lack of genetic potential availab.e in wild and cultivated material. In contrast, b.eeding at the diploid level, in particular in comb.nation with self-compatib.lity, will allow the fixation of b.neficial alleles to homozygosity.

关键词： Genetic Load Potato Hyb.id Diploid b.eeding

Cystine oligomers successfully attached to peptide cysteine- rich fib.ils

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Frontiers of Chemical Science and Engineering 2016年第1期10卷 99-102页

作者： christian b.rtolini Mingdong Dong Interdisciplinary Nanoscience Center (iNANO) Aarhus University Aarhus C 8000 Denmark

Amyloid peptides are renowned to b. related to neurodegenerative diseases, however, a fruitful avenue is to employ them as high-performance nanomaterials. These materials b.nefit from the intrinsic outstanding mechanical rob.stness of the amyloid b.ckb.ne made of r-strands. In this work, we exploited amyloid-like fib.ils as functional material to attach pristine L-cysteine aggregates （cystine oligomers） and gold nanoparticles, without the need of templating compounds. This work will open new avenues on functional materials design and their realisation.

关键词： cysteine peptide fib.ils gold nanoparticles amyloids oligomers nanomaterials

The Influence of Tropical Cyclones to the Plant Productivity Indices along the Coast of Tanzania

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Atmospheric and Climate Sciences 2021年第3期11卷 589-613页

作者： Komb. Hamad Kai Yohanna Wilson Shaghude Agnes Lawrence Kijazi christian b. Uiso Tanzania Meteorological Authority (TMA) Zanzibar Tanzania Institute of Marine Sciences (IMS) of University of Dar es Salam (UDSM) Mizingani Road Zanzibar Tanzania TMA Ubungo Plaza Dar es Salaam Tanzania Department of Physics University of Dar es Salaam (UDSM) Tanzania

The study investigated the influence of Tropical cyclone (TCs) to the plant productivity indices along the coast of Tanzania using b.th field ob.ervations and change detection methods. These indices are normally designed to maximize the sensitivity of the vegetation characteristics and are very crucial in monitoring droughts intensity, yield and b.omass amongst others. The study used three types of satellite imageries including the 16 days Moderate Resolution Imaging Spectroradiometer (MODIS) of 250 × 250 m resolution;8 days Landsat 7 enhanced thematic mapper (ETM) with resolution of 30 × 30 m composites, and 5 Landsat 8 (LC8) images, to determine the patterns and the variability of the Normalized Difference Vegetation Index (NDVI) and Enhanced Vegetation Index (EVI) and TCs impacts on vegetation. Moreover, we used Tropical Rainfall Measuring Mission (TRMM) data and the daily to monthly rainfall data from Tanzanian Meteorological Authority (TMA). The change detection b.tween the pre and post storm (TCs) conditions was used to analyse inter annual variab.lity of EVI over Chwaka, Rufiji and Pugu— Kazimzumb.i. The changes in NDVI and EVI and monthly rainfall at the coastal stations were calculated, plotted and analyzed. The results revealed that, highest EVI values over coastal Tanzania were ob.erved during March and April, and minimum (low) values in November. The results for EVI changes b.sed on pre and post storm conditions revealed that most ob.erved stations and most TCs led to significant EVI changes which ranged from -0.05 to 0.19, and -0.3 to 0.22, for MODIS and L7 ETM data, respectively. As for the spatial changes in NDVI results revealed that, TCs (Besija and Fobane) were associated with positive NDVI changes i.e. (enhancement) of >0.51 and >0.31, and NDVI reduction (i.e. negative

关键词： Tropical Cyclones (TCs) Impacts Normalized Vegetation Index (NDVI) Enhanced Vegetation Index (EVI) Rainfall MODIS) Tanzania

3-D Characterization of CdSe Nanoparticles Attached to Carb.n Nanotub.s

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Nano Research 2008年第1期1卷 89-97页

作者： Ana b.Hungría b.atriz H.Juárez christian Klinke Horst Weller Paul A.Midgley Department of Materials Science and Metallurgy University of CambridgePembroke StreetCambridgeCB23QZUK 2 Institute of Physical ChemistryUniversity of Hamburg20146 HamburgGermany

The crystallographic structure of CdSe nanoparticles attached to carb.n nanotub.s has b.en elucidated b. means of high resolution transmission electron microscopy and high angle annular dark field scanning transmission electron microscopy *** rod-like nanoparticles,grown in solution together with carb.n nanotub.s,undergo a morphological transformation and b.come attached to the carb.n *** tomography reveals that the nanoparticles are hexagonal-b.sed with the(001)planes epitaxially matched to the outer graphene layer.

关键词： Electron tomography CdSe nanoparticles STEM HRTEM carb.n nanotub.s

Can mouse models mimic sporadic Alzheimer’s disease?

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Neural Regeneration Research 2020年第3期15卷 401-406页

作者： b.ttina M.Foidl christian Humpel Lab.ratory of Psychiatry and Experimental Alzheimer’s Research Medical University of Innsbruck

Alzheimer’s disease(AD)is a progressive neurodegenerative disorder and the most common form of dementia *** age is the main risk factor,>97%of all AD cases are of sporadic origin,potentiated b. various risk factors associated with life style and starting at an age>60 ***b. mutations in the amyloid precursor protein or Presenilins 1 or 2,and symptoms already start at an ageb.en developed and used,with mutations in the APP or presenilin or comb.nations(3×Tg,5×Tg).However,such transgenic mouse models more likely mimic the genetic form of AD and no information can b. given how sporadic forms *** risk genes,such as Apolipoprotein E4 and TREM-2 enhance the risk of sporadic AD,b.t also many risk factors associated with life style(e.g.,diab.tes,hypercholesterolemia,stress)may play a *** this review we discuss the current situation regarding AD mouse models,and the prob.ems to develop a sporadic mouse model of AD.

关键词： Alzheimer’s disease b.ta-amyloid cereb.al amyloid angiopathy cognitive impairment sporadic and genetic mouse models tau vascular risk factors

Clinical and Etiological Characteristics of Hemiplegia at the University Regional Hospital Center Ouahigouya

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World Journal of Neuroscience 2020年第1期10卷 22-28页

作者： Alassane Dravé christian Napon Anselme A. Dab.lgou Salam Ouedraogo Jean b. Kab.ré Department of General Medicine of the Ouahigouya Regional University Hospital Center Ouahigouya Burkina Faso Neurology Department of Yalgado OUEDRAOGO Ouagadougou University Hospital Center Ouagadougou Burkina Faso

Ob.ective: To describ. the clinical and etiological characteristics of hemiplegia in the northern region of b.rkina Faso. Methodology: This was transversal with a descriptive and analytical study of one hundred and ninety-six hemiplegic patients in charge of general medicine at the Ouahigouya Regional University Hospitalfrom Novemb.r 2015 to Novemb.r 2017. Results: The majority of patients had a b.utal hemiplegia predominant on the right. The sample consisted mainly of male patients with a mean age of 58 years. High b.ood pressure was the main factor of vascular risk. The cereb.ovascular accident (58.7%) was the main pathology diagnosed. Most patients received symptomatic management. Physiotherapy was performed in 29.6% of patients. The clinical outcome at discharge was marked b. the persistence of hemiplegia in more than 90.8% of patients. There was an improvement in the average MIF score at the exit. Conclusion: The lack of computed tomography and neuro-resuscitation unit were the main factors limiting the management of hemiplegia in our context.

关键词： Hemiplegia General Medicine Ouahigouya

Heart rate variab.lity and the influence of craniosacral therapy on autonomous nervous system regulation in persons with sub.ective discomforts:a pilot study

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Journal of Integrative Medicine 2014年第3期12卷 156-161页

作者： Wanda Girsb.rger Ulricke b.nziger Gerhard Lingg Harald Lothaller Peter-christian Endler Interuniversity College for Health and Development Castle of Seggau8042 GrazAustria Practice for Craniosacral Therapy Kronenstrasse 488006 ZurichSwitzerland

b.CKGROUND： Sub.ective discomforts in a preclinical range are often due to imb.lanced autonomic nervous system activity, which is a focus of craniosacral therapy. Ob.ECTIVE： The aim of this work was to determine any changes in heart rate variab.lity （HRV） in a study on craniosacral therapy. DESIGN, SETTING, PARTICIPANTS AND INTERVENTIONS： This is a quasi-experimental （controlled） study with cross-over design. In a private practice, measurements were performed on 31 patients with sub.ective discomforts b.fore and after a control and an intervention period. HRV was determined using a device that requires a measuring time of 140 s and electrode contact only with the fingertips. Main PRIMARY OUTCOME MEASURES： HRV change under the influence of a defined onetime intervention （test intervention） with craniosacral therapy versus control （defined rest period）. RESULTS： Standard deviation of all RR-intervals （ms） and total power of RR-interval variab.lity in the frequency range （ms2） were together interpreted as an indicator of test sub.ects＇ autonomic nervous activity and as a measure of their ab.lity to cope with demands on their health. Neither of these parameters increased during the control period （P〉0.05）, whereas during the test intervention period there was an increase in b.th （P〈0.05, P〈0.01）. Nevertheless, interactions b.tween treatment and the increase were statistically not significant （P〉0.05）. No changes were ob.erved in the low frequency/high frequency ratio （sympathetic-vagal b.lance） in the course of the control or the test intervention period （P〉0.05）. CONCLUSION： Craniosacral treatment had a favourab.e effect on autonomic nervous activity. This in itself is an interesting result, b.t further research will b. needed to distinguish specific effects of craniosacral therapy technique from less specific therapist-client interaction effects.

关键词： massage autonomic nervous system electrocardiography adult complementarytherapies pilot projects