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High Power Laser Science and Engineering 2024年第1期12卷 60-73页

作者： Shikha Bhadoria Mattias Marklund Christoph H.Keitel max-planck-institut für Kernphysik HeidelbergGermany Department of Physics University of GothenburgGöteborgSweden

The impact of radiation reaction and Breit±Wheeler pair production on the acceleration of fully ionized carbon ions driven by an intense linearly polarized laser pulse has been investigated in the ultra-relativistic transparency *** initial expectations, the radiation reaction and pair production at ultra-high laser intensities are found to enhance the energy gained by the ions. The electrons lose most of their transverse momentum, and the additionally produced pair plasma of Breit±Wheeler electrons and positrons co-streams in the forward direction as opposed to the existing electrons streaming at an angle above zero degree. We discuss how these observations could be explained by the changes in the phase velocity of the Buneman instability, which is known to aid ion acceleration in the breakout afterburner regime, by tapping the free energy in the relative electron and ion streams. We present evidence that these non-classical effects can further improve the highest carbon ion energies in this transparency regime.

关键词： ion acceleration quantum electrodynamic effects

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Discovery potential of the Glashow resonance in an air shower neutrino telescope

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Chinese Physics C 2024年第8期48卷 266-275页

作者： Guo-Yuan Huang School of Mathematics and Physics China University of GeosciencesWuhan 430074China max-planck-institut für Kernphysik Saupfercheckweg 169117 HeidelbergGermany

The in-ice or in-water Cherenkov neutrino telescope,such as IceCube,has already proved its power in measuring the Glashow resonance by searching for the bump around E_(ν)=6.3PeV arising from the W-boson *** are many proposals for the next few decades for observations of cosmic tau neutrinos with extensive air showers,also known as tau neutrino *** air shower telescope is,in principle,sensitive to the Glashow resonance via the channel W→τν_(τ)followed by the tau decay in the air(e.g.,TAMBO,which has a geometric area of approximately 500km^(2)).Using a thorough numerical analysis,we find that the discovery significance can be up to 90%with a TAMBO-like setup if PeV neutrinos primarily originate from neutron decays,considering the flux parameters measured by IceCube as the *** presence of new physics affecting the neutrino flavor composition can also increase the ***,if ultrahigh-energy neutrinos are dominantly produced from meson decays,it will be statistically difficult for an advanced proposal such as TAMBO to discriminate the Glashow resonance induced byν¯e from the intrinsicντ/ν¯_(τ)*** have identified several limitations for such advanced telescopes,in comparison with the in-ice or in-water telescope,when measuring resonances:(i)a suppressed branching ratio of 11%for the decay W→τν_(τ);(ii)the smearing effect and reduced acceptance because the daughter neutrino takes away(y)∼75%of the energy from the W decay;and(iii)a large attenuation effect for Earth-skimming neutrinos with the resonance.

关键词： Ultrahigh-energy neutrinos Neutrino telescopes Glashow resonance

Influence of symmetric and asymmetric rolling on texture evolution of work-hardened AA 5xxx aluminium alloy

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Transactions of Nonferrous Metals Society of China 2024年

作者： Matja? Godec Stefan Zaefferer Jakob Kraner ?rtomir Donik Irena Paulin institute of Metals and Technology max-planck-institut für Eisenforschung， max-planck-Strasse 1 Impol 2000 d.d.， Partizanska cesta 38

The textures and microstructures of hot- and cold-rolled sheets of an AA 5454 aluminium alloy were studied， with special attention paid to comparing the texture development for the symmetric and asymmetric cold rolling. Scanning electron microscopy with electron-backscatter diffraction was used to monitor the development of the microstructure in the differently deformed and additionally annealed samples. Details of the formations and transformations of individual texture components occurring during the rolling processes were observed and discussed. The average grain sizes， textures and mechanical properties were correlated and explained for the symmetric and asymmetric cold-rolled samples. The asymmetric rolling is beneficial in terms of deep drawability because it reduces the planar anisotropy of the annealed material due to the decrease of the Cube， Goss， rotated Cube and η- fibre texture components and the same time strengthens X1- and X2-fibre texture components which are shear texture components and improve deep drawability. During the asymmetric cold rolling， the temperature increases due to friction， triggering recrystallisation processes and leading to larger grains. It was also confirmed that asymmetric cold rolling uses less rolling force and consequently less energy to produce a final material with better formability， particularly earing.

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Snapshot imaging of ultrashort electron bunches

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Light(Science & Applications) 2024年第7期13卷 1226-1228页

作者： Andreas Döpp Ludwig-maximilian-Universität München Am Coulombwall 185748GarchingGermany max planck institut für Quantenoptik Hans-Kopfermann-Strasse 1Garching85748Germany

New measurements combine spatial and temporal information from optical transition radiation to estimate the three-dimensional structure of electron bunches from a laser wakefield accelerator.

关键词： ultrashort Snapshot electron

Peripheral immune cell-derived matrix metalloprotease 8(MMP8):brain trafficking promotes depression-like behavior

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Signal Transduction and Targeted Therapy 2024年第6期9卷 2357-2358页

作者： Dietmar Spengler Theo rein max planck institute of Psychiatry Epigenomics of Early-Life Stress80804 MunichGermany max planck institute of Psychiatry Molecular Pathways of Depression80804 MunichGermany

In a study recently published in Nature,Cathomas et al.1 report that social stress in mice increases the levels of matrix metalloprotease(MMP)8 in circulating immune cells,thereby altering extracellular space(ECS)and neuronal activity,and ultimately social behavior in susceptible *** deficits resembled those from major depressive disorder(MDD)raising the prospect of MMP8 as a new druggable target in tailored treatments.

关键词： MMP8 al. behavior

Data-driven Simulations of Magnetic field Evolution in Active region 11429:Magneto-frictional Method Using PENCIL CODE

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research in Astronomy and Astrophysics 2024年第2期24卷 74-82页

作者： P.Vemareddy Jorn Warnecke Ph.A.Bourdin Indian institute of Astrophysics Sarjapur roadII BlockKoramangalaBengaluru-560034India max-planck-institut für sonnensystemforschung Justus-von-Liebig-Weg 3D-37077 GöttingenGermany institute of Physics University of GrazUniversitätsplatz 5A-8010 GrazAustria

Coronal magnetic fields evolve quasi-statically over long timescales and dynamically over short *** of now there exist no regular measurements of coronal magnetic fields,and therefore generating the coronal magnetic field evolution using observations of the magnetic field at the photosphere is a fundamental requirement to understanding the origin of transient phenomena from solar active regions(Ars).Using the magneto-friction(Mf)approach,we aim to simulate the coronal field evolution in the solar Ar *** Mf method is implemented in the open source PENCIL CODE along with a driver module to drive the initial field with different boundary conditions prescribed from observed vector magnetic fields at the *** order to work with vector potential and the observations,we prescribe three types of bottom boundary drivers with varying free-magnetic *** Mf simulation reproduces the magnetic structure,which better matches the sigmoidal morphology exhibited by Atmospheric Imaging Assembly(AIA)images at the pre-eruptive *** found that the already sheared field further driven by the sheared magnetic field will maintain and further build the highly sheared coronal magnetic configuration,as seen in Ar ***-driven Mf simulation is a viable tool to generate the coronal magnetic field evolution,capturing the formation of the twisted flux rope and its eruption.

关键词： Sun corona-Sun evolution-Sun magnetic fields-Sun photosphere

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Peri-implant gas accumulation in response to magnesium-based musculoskeletal biomaterials:reframing current evidence for preclinical research and clinical evaluation

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Journal of Magnesium and Alloys 2024年第1期12卷 59-71页

作者： Yu Sun Heike Helmholz regine Willumeit-römer institute of Metallic Biomaterials Helmholtz-Zentrum HereonMax-Planck-Str.1Geesthacht 21502Germany

Historically,the rapid degradation and massive gas release from magnesium(Mg)implants resulted in severe emphysema and mechanical *** the advent of new alloys and surface treatment methods,optimized Mg implants have re-entered clinics since last decade with reliable ***,the optimization aims at slowing down the degradation process,rather than exemption of the gas *** study involved a systematic evaluation of current preclinical and clinical evidence,regarding the physical signs,symptoms,radiological features,pathological findings and complications potentially associated with peri±implant gas accumulation(PIGA)after musculoskeletal Mg *** literature search identified 196 potentially relevant publications,and 51 papers were enrolled for further analysis,including 22 preclinical tests and 29 clinical studies published from 2005 to *** Mg-based materials have been evaluated in animal research,and the application of pure Mg and Mg alloys have been reported in clinical follow-ups involving multiple anatomical sites and musculoskeletal *** tissue and intraosseous PIGA are common in both animal tests and clinical follow-ups,and potentially associated with certain adverse *** examinations especially micro-CT and clinical CT scans provide valuable information for quantitative and longitudinal *** according to simulation tests involving Mg implantation and chemical processing,tissue fixation could lead to an increase in the volume of gas cavity,thus the results obtained from ex vivo imaging or histopathological evaluations should be interpreted with *** still lacks standardized procedures or consensus for both preclinical and clinical evaluation of ***,by providing focused insights into the topic,this evidence-based study will facilitate future animal tests and clinical evaluations,and support developing biocompatible Mg implants for the treatment of musculoskeletal

关键词： Magnesium implant Degradation Hydrogen Gas release Postoperative follow-up

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from the unknown to spotlight:newly identified hormone adjusts hepatic cholesterol synthesis to dietary uptake

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Signal Transduction and Targeted Therapy 2024年第7期9卷 2845-2847页

作者： Yakum Bertrand Nkeh resul Gökberk Elgin Gesine Saher Project Group Biology of Lipids Department of NeurogeneticsMax Planck Institute for Multidisciplinary SciencesGöttingenGermany

In a study published in Cell,Hu and colleagues discovered that the signaling activity of the intestinal hormone Cholesin leads to the attenuation of hepatic cholesterol synthesis in response to intestinal absorption thereby maintaining homeostatic levels of circulating cholesterol.1 These findings have major translational implications as they provide a potential new target for the management of hypercholesterolemia and associated disorders.

关键词： cholesterol hepatic synthesis

Steroidal scaffold decorations in Solanum alkaloid biosynthesis

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Molecular Plant 2024年第8期17卷 1236-1254页

作者： rosalind Lucier Mohamed O.Kamileen Yoko Nakamura Sofia Serediuk ranjit Barbole Jens Wurlitzer Maritta Kunert Sarah Heinicke Sarah E.O'Connor Prashant D.Sonawane Department of Natural Product Biosynthesis Max Planck Institute for Chemical Ecology07745 JenaGermany research Group Biosynthesis and NMr Max Planck Institute for Chemical Ecology07745 JenaGermany Biochemical Sciences Division CSIR-National Chemical LaboratoryPune 411008MaharashtraIndia

Steroidal glycoalkaloids(SGAs)are specialized metabolites produced by hundreds of Solanum species,including important vegetable crops such as tomato,potato,and *** it has been known that SGAs play important roles in defense in plants and“anti-nutritional"effects(e.g.,toxicity and bitterness)to humans,many of these molecules have documented anti-cancer,anti-microbial,antiinflammatory,anti-viral,and anti-pyretic *** these,α-solasonine andα-solamargine isolated from black nightshade(Solanum nigrum)are reported to have potent anti-tumor,anti-proliferative,and anti-inflammatory ***,α-solasonine andα-solamargine,along with the core steroidal aglycone solasodine,are the most widespread SGAs produced among the Solanum ***,it is still unknown how plants synthesize these bioactive steroidal *** comparative metabolomictranscriptome-guided approach,biosynthetic logic,combinatorial expression in Nicotiana benthamiana,and functional recombinant enzyme assays,here we report the discovery of 12 enzymes from *** that converts the starting cholesterol precursorto solasodine aglycone,and the downstreamα-solasonine,α-solamargine,and malonyl-solamargine SGA *** further identified six enzymes from cultivated eggplant that catalyze the production ofα-solasonine,α-solamargine,and malonyl-solamargine SGAs from solasodine aglycone via glycosylation and atypical malonylation *** work provides the gene tool box and platform for engineering the production of high-value,steroidal bioactive molecules inheterologoushosts usingsyntheticbiology.

关键词： steroidal glycoalkaloids Solanum biosynthetic pathway α-solamargine malonyl-solamargine specialized metabolites

On-the-fly precision spectroscopy with a dual-modulated tunable diode laser and Hz-level referencing to a cavity

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Advanced Photonics 2024年第4期6卷 36-44页

作者： Shuangyou Zhang Toby Bi Pascal Del’Haye max planck institute for the Science of Light friedrich-Alexander Universit?t Erlangen-Nürnberg Department of Physics

Advances in laser spectroscopy have enabled many scientific breakthroughs in physics, chemistry,biology, and astronomy. Optical frequency combs pushed measurement limits with ultrahigh-frequency accuracy and fast-measurement speed, while tunable-diode-laser spectroscopy is used in scenarios that require high power and continuous spectral coverage. Despite these advantages of tunable-diode-laser spectroscopy, it is challenging to precisely determine the instantaneous laser frequency because of fluctuations in the scan speed. Here, we demonstrate a simple spectroscopy scheme with a frequencymodulated diode laser that references the laser on-the-fly to a fiber cavity. The fiber cavity's free spectral range is on-the-fly calibrated with sub-10-Hz frequency precision. We achieve a relative precision of the laser frequency of 2 × 10-8for an 11-THz frequency range at a measurement speed of 1 THz∕s. This is an improvement of more than 2 orders of magnitude compared to existing diode-laser-spectroscopy *** scheme provides precise frequency calibration markers, while simultaneously tracking the instantaneous scan speed of the laser. We demonstrate the versatility of our method through various applications, including dispersion measurement of a fiber, ultrahigh-Q microresonators, and spectroscopy of a hydrogen fluoride gas cell. The simplicity, robustness, and low cost of this spectroscopy scheme are valuable for out-of-the-lab applications like lidar and environmental monitoring.

关键词： frequency comb gas spectroscopy integrated photonics radio-frequency modulation tunable laser spectroscopy