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Laser-induced plasma formation in water with up to 400 mj double-pulse LIBS

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Plasma Science and Technology 2024年第1期26卷 93-100页

作者： Marion HENKEL Michelle SIEMENS Ralf METHLING Benjamin EMDE j.rg HERMSDORF Steffen FRANKE Diego GONZALEZ Leibniz Institute for Plasma Science and Technology(INP) Felix-Hausdorff-Straße 2Greifswald 17489Germany Laser Zentrum Hannover e.V.(LZH) Hollerithallee 8Hannover 30419Germany

Double-pulse LIBS is a promising technique for deep-sea *** measurements in shallow water with up to 400 mj each pulse were done to select laser parameters which promote optimized spectral line emission from plasma even at elevated pressures,where line broadening until loss of most of the spectral information can *** emission spectroscopy,using a Czerny-Turner spectrometer,has been applied to investigate the dependence of the emitted radiation on laser parameters and hydrostatic *** has been found,that higher laser pulse energies,especially with short pulse delay as required in high water pressure,can also have an adverse effect on the measured spectrum.

关键词： double-pulse LIBS underwater plasma formation emission spectrosocpy

Graphene-calcium carbonate coating to improve the degradation resistance and mechanical integrity of a biodegradable implant

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journal of Magnesium and Alloys 2024年第1期12卷 394-404页

作者： Lokesh Choudhary Parama Chakraborty Banerjee R.K.Singh Raman Derrek E.Lobo Christopher D.Easton Mainak Majumder Frank Witte j.rg F.Löffler Department of Mechanical and Aerospace Engineering Monash UniversityClayton CampusMelbourneVIC 3800Australia Department of Chemical and Biological Engineering Monash UniversityClayton CampusMelbourneVIC 3800Australia Nanoscale Science and Engineering Laboratory(NSEL) Bldg 37Monash UniversityClayton CampusMelbourneVIC 3800Australia CSIRO Materials Science and Engineering Bayview AvenueClaytonVIC 3168Australia julius Wolff Institute and Berlin Brandenburg Center for Regenerative Therapies Charité–Universitätsmedizin BerlinAugustenburger Platz 113353 BerlinGermany Laboratory of Metal Physics and Technology Department of MaterialsETH Zurich8093 ZurichSwitzerland

Biodegradable implants are critical for regenerative orthopaedic procedures,but they may suffer from too fast corrosion in human-body *** necessitates the synthesis of a suitable coating that may improve the corrosion resistance of these implants without compromising their mechanical *** this study,an AZ91 magnesium alloy,as a representative for a biodegradable Mg implant material,was modified with a thin reduced graphene oxide(rgO)-calcium carbonate(CaCO_(3))composite *** analytical and in-vitro electrochemical characterization reveals that this coating significantly improves the corrosion resistance and mechanical integrity,and thus has the potential to greatly extend the related application field.

关键词： Graphene coating Biodegradable implant Hydroxyapatite Corrosion Magnesium alloy

Acid tolerance of lactate-utilizing bacteria of the order Bacteroidales contributes to prevention of ruminal acidosis in goats adapted to a high-concentrate diet

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Animal Nutrition 2023年第3期14卷 130-140页

作者： Zhongyan Lu Lingmeng Kong Shenhao Ren j.rg raschenbach Hong Shen Key Lab of Animal Physiology and Biochemistry College of Veterinary MedicineNanjing Agricultural UniversityNanjingJiangsuChina College of Life Science Nanjing Agricultural UniversityNanjingJiangsuChina Institute of Veterinary Physiology Freie Universitat BerlinBerlinGermany Bioinformatics Center Academy for Advanced Interdisciplinary StudiesNanjing Agricultural UniversityNanjingJiangsuChina

The rapid accumulation of organic acids,particularly lactate,has been suggested as the main cause of ruminal acidosis(RA)for ruminants fed high-concentrate *** research has shown that a gradual shift from low-to high-concentrate diets within 4 to 5 weeks effectively reduces the risk for ***,the mechanisms remain *** this study,20 goats were randomly allocated into four groups(n=5)and fed with a diet containing a weekly increasing concentrate portion of 20%,40%,60%,and 80%over 28 *** d 7,14,21,and 28,one group(named C20,C40,C60,and C80 according to the last concentrate level that they received)was killed and the ruminal microbiome was *** acidosis was not detected in any of the goats during the ***,ruminal pH dropped sharply from 6.2 to 5.7(Pjor types of sugar transporter for lactate-producing bacteria(LPB)and lactate-utilizing bacteria(LUB),***,more adenosine triphosphate was required for the phosphorylation of sugars to initiate their catabolic pathways in LPB compared to ***,the low dependence of sugar transport systems and

关键词： Ruminal microbiome Ruminal acidosis Acid tolerance Lactate metabolism

High-dimensional neural network potentials for magnetic systems using spin-dependent atom-centered symmetry functions

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npj Computational Materials 2021年第1期7卷 1541-1551页

作者： Marco Eckhoff j.rg Behler Universität Göttingen Institut für Physikalische ChemieTheoretische ChemieTammannstrasse 637077 GöttingenGermany Universität Göttingen International Center for Advanced Studies of Energy Conversion(ICASEC)Tammannstrasse 637077 GöttingenGermany

Machine learning potentials have emerged as a powerful tool to extend the time and length scales of first-principles quality ***,most machine learning potentials cannot distinguish different electronic spin arrangements and thus are not applicable to materials in different magnetic *** we propose spin-dependent atom-centered symmetry functions as a type of descriptor taking the atomic spin degrees of freedom into *** used as an input for a high-dimensional neural network potential(HDNNP),accurate potential energy surfaces of multicomponent systems can be constructed,describing multiple collinear magnetic *** demonstrate the performance of these magnetic HDNNPs for the case of manganese oxide,*** method predicts the magnetically distorted rhombohedral structure in excellent agreement with density functional theory and *** efficiency allows to determine the Néel temperature considering structural fluctuations,entropic effects,and *** method is general and is expected to be useful also for other types of systems such as oligonuclear transition metal complexes.

关键词： magnetic symmetry neural

Development of ^(18)F-labeled radiotracers for neuroreceptor imaging with positron emission tomography

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Neuroscience Bulletin 2014年第5期30卷 777-811页

作者： Peter Brust j.rg van den Hoff j.rg Steinbach Helmholtz-Zentrum Dresden-Rossendorf Institute of Radiopharmaceutical Cancer ResearchPermoserstrasse 15Leipzig04318Germany

Positron emission tomography （PET） is an in vivo molecular imaging tool which is widely used in nuclear medicine for early diagnosis and treatment follow-up of many brain diseases. PET uses biomolecules as probes which are labeled with radionuclides of short half-lives, synthesized prior to the imaging studies. These probes are called radiotracers. Fluorine-18 is a radionuclide routinely used in the radiolabeling of neuroreceptor ligands for PET because of its favorable half-life of 109.8 min. The delivery of such radiotracers into the brain provides images of transport, metabolic, and neurotransmission processes on the molecular level. After a short introduction into the principles of PET, this review mainly focuses on the strategy of radiotracer development bridging from basic science to biomedical application. Successful radiotracer design as described here provides molecular probes which not only are useful for imaging of human brain diseases, but also allow molecular neuroreceptor imaging studies in various small-animal models of disease, including genetically- engineered animals. Furthermore, they provide a powerful tool for in vivo pharmacology during the process of pre-clinical drug development to identify new drug targets, to investigate pathophysiology, to discover potential drug candidates, and to evaluate the pharmacokinetics and pharmacodynamics of drugs in vivo.

关键词： Alzheimer's disease autoradiography blood-brain barrier brain tumor cholinergic system kinetic modeling metabolism molecular imaging neurodegeneration positron emission tomography precursor psychiatric disorder radiotracer sigma receptor

Tracking moving magnetic features in the photosphere

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Science China(Physics,Mechanics & Astronomy) 2009年第11期52卷 1737-1748页

作者： BCHNER j.rg Max-Planck-Institut fr Sonnensystemforschung

This research aims for an objective identification, tracking, and a statistical analysis of the Moving Magnetic Features (MMFs) around sunspots using SOHO/MDI high-resolution magnetograms. To this end, we develop a computerized tracking program and study the motion and magnetism of the outflows of MMFs around 26 sunspots. Our method locates 4-27 MMFs per hour, with higher counts for large sunspots. We differentiate MMFs into type α that have a polarity opposite to the parent sunspots, and type β that share the sunspot's polarity. These sunspots' MMF subsets exhibit a wide range of central tendencies which have distinctive correlations with the sunspots. In general, α-MMFs emerge farther from the sunspot, carry less flux, and move faster than β-MMFs. The typical α/β-MMFs emerge at 2.2 - 8.1/0.1 - 3.2 Mm outside the penumbra limb, with lifetimes of 1.1 - 3.1/1.3 - 2.0 h. They are 1.1 - 6.6/1.4 - 3.6 Mm2 in area and carry 1.4 - 12.5/4.8 - 11.4 ×1018 Mx of flux. They travel a distance of 2.7 - 5.9/2.8 - 3.6 Mm with the speed of 0.5 - 0.9/0.4 - 0.7 km/s. Compared to the α-MMFs produced by large sunspots, those of small spots are smaller. They emerge closer to sunspot, move farther, live longer, and carry less flux. β-MMFs show much less correlation with the sunspots. The flux outflow carried by the MMFs ranges from 0.2 to 8.3 × 1019Mx· h-1 and does not show obvious correlation with the sunspots' evolution. The frequency distributions of the MMFs' distance traveled, area, and flux are exponential. This suggests the existence of numerous small, weak, and short-timescale magnetic objects which might contribute to the sunspot flux outflow.

关键词： sun activity magnetic fields photosphere sunspots moat moving magnetic features

Indoor localization for pedestrians with real-time capability using multi-sensor smartphones

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Geo-Spatial Information Science 2019年第2期22卷 73-88,I0001页

作者： Catia Real Ehrlich j.rg Blankenbach Geodetic Institute and Chair for Computing in Civil Engineering&Geo Information Systems RWTH Aachen UniversityAachenGermany

The localization of persons or objects usually refers to a position determined in a spatial reference ***,this is usually accomplished with Global Navigation Satellite Systems(GNSS).However,the automatic positioning of people in GNSS-free environments,especially inside of buildings(indoors)poses a huge ***,satellite signals are attenuated,shielded or reflected by building components(*** or ceilings).For selected applications,the automatic indoor positioning is possible based on different technologies(***,RFID,or UWB).However,a standard solution is still not *** indoor positioning systems are only suitable for specific applications or are deployed under certain conditions,*** infrastructures or sensor ***,as popular cost-effective multi-sensor systems,is a promising indoor localization platform for the mass-market and is increasingly coming into ***’s devices are equipped with a variety of sensors that can be used for indoor *** this contribution,an approach to smartphone-based pedestrian indoor localization is *** novelty of this approach refers to a holistic,real-time pedestrian localization inside of buildings based on multisensor smartphones and easy-to-install local positioning *** this purpose,the barometric altitude is estimated in order to derive the floor on which the user is *** 2D position is determined subsequently using the principle of pedestrian dead reckoning based on user's movements extracted from the smartphone *** order to minimize the strong error accumulation in the localization caused by various sensor errors,additional information is integrated into the position *** building model is used to identify permissible(***,passageways)and impermissible(***)building areas for the *** technologies contributing to higher precision and robustness are also *** the fusion of diffe

关键词： Indoor positioning MEMS recursive Bayesian estimation particle filter sensor fusion Bluetooth beacons WLAN fingerprinting magnetic anomalies

Switching off DNA repair—how colorectal cancer evades targeted therapies through adaptive mutability

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Signal Transduction and Targeted Therapy 2020年第1期5卷 2343-2344页

作者： j.rg Fahrer Division of Food Chemistry and Toxicology Department of ChemistryTechnical University of Kaiserslautern67663 KaiserslauternGermany

A very recent study by Russo et *** in Science demonstrates that colorectal cancer(CRC)cells adapt to targeted therapies by downregulating DNA repair at the expense of an increased mutation frequency and microsatellite instability(MSI).1 The authors intriguingly showed that CRC cells are capable of activating stress-induced mutagenesis similar to unicellular organisms in a transient and controlled manner,allowing them to survive under targeted therapies(Fig.1).

关键词： targeted colorectal al

Entire curves,integral sets and principal bundles

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Science China Mathematics 2011年第8期54卷 1803-1814页

作者： WINKELMANN j.rg Lehrstuhl Analysis Ⅱ Mathematisches InstitutRuhr-Universitt BochumBochum 44780Germany

We compare the behaviour of entire curves and integral sets,in particular in relation to locally trivial fiber bundles,algebraic groups and finite ramified covers over semi-abelian varieties.

关键词： entire curves integral point sets semi-abelian variety algebraic group