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The Reality of Baryonic Acoustic Oscillations

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journal of Modern Physics 2024年第3期15卷 377-402页

作者： j. c. Botke Ronin Institute Montclair New Jersey USA

The initial idea for baryonic acoustic oscillations (BAO) came about during early efforts to understand the origin of galaxies by studying perturbed versions of the Friedmann-Robertson-Walker (FRW) model. In more recent times, the emphasis has shifted to the idea that 2-point galaxy correlations embedded in the distribution of matter by the BAO could be used as a standard ruler to fix the parameters of cosmological models. In this paper, we first consider the actual business of extracting the correlation length from large data sets of measured galaxy locations. To facilitate this process, we introduce a much-improved method for extracting the correlation peak from the data set. Fundamental to this process in any model is the use of a fiducial cosmological model to transition from redshift space to comoving coordinate space where the correlations actually exist. The belief is that the correlation length so determined can then be reverted to redshift space to fix the parameters of cosmological models. We show, however, that this process is circular and hence of no value whatsoever for fixing model parameters. All one obtains are the parameters of the model used to transition to comoving space in the first place. Finally, we present simple arguments that show that the idea of BAO being responsible for the structure of the universe, i.e. the cosmic web, is unworkable.

关键词： Baryonic Acoustic Oscillations Two-Point correlations cMB Anisotropy Early Universe Time-Varying curvature

The Origin of cosmic Structures Part 6: cMB Anisotropy

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journal of High Energy Physics, Gravitation and cosmology 2024年第1期10卷 257-276页

作者： j. c. Botke Ronin Institute Montclair New Jersey USA

In a recent series of papers, we introduced a new model of nucleosynthesis in which the matter content of the universe came into existence at a time of about 4 × 10-5 s. At that time, a small percentage of the vacuum energy was converted into neutron/antineutron pairs with a very small excess of neutrons. This process was regulated by an imprint that was established in the vacuum during an initial Plank-era inflation. Immediately after their inception, annihilation and charge exchange reactions proceeded at a very high rate and ran to completion after an interval of about 10-11 s. By then, all the antibaryons had disappeared thereby establishing the matter/antimatter asymmetry of the universe. What remained were very high densities of mesons and leptons, somewhat lower densities of protons and neutrons, and finally, the very high density of photons that eventually became the cMB. The density of matter so created varied from one location to another in such a manner as to account for all cosmic structures and because the energy density of the photons varied in proportion to that of the matter, the cMB-to-be came into existence with an anisotropic spectrum already in place. For structures, the size of galaxy clusters, the initial anisotropy magnitudes were on the order of 25%. In this paper, we will follow the subsequent evolution of the photons and show that this model predicts with accuracy the temperature of the warmest anisotropies in the observed cMB spectrum. .

关键词： cMB Anisotropy Dispersion Nucleosynthesis Early Universe Time-Varying curvature

cD4^(+)T cells produce IFN-I to license cDc1s for induction of cytotoxic T-cell activity in human tumors

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cellular & Molecular Immunology 2024年第4期21卷 374-392页

作者： Xin Lei Daniël c.de Groot Marij j.P.Welters Tom de Wit Ellen Schrama Hans van Eenennaam Saskia j.Santegoets Timo Oosenbrug Annemarthe van der Veen joris L.Vos charlotte L.Zuur Noel F.c.c.de Miranda Heinz jacobs Sjoerd H.van der Burg jannie Borst Yanling Xiao Department of Immunology Leiden University Medical CenterLeidenThe Netherlands Oncode Institute Leiden University Medical CenterLeidenThe Netherlands Department of Tumor Biology and Immunology The Netherlands Cancer InstituteAmsterdamThe Netherlands Department of Medical Oncology Oncode InstituteLeiden University Medical CenterLeidenThe Netherlands IMMIOS B.V. OssThe Netherlands Division of Medical Oncology The Netherlands Cancer InstituteAmsterdamThe Netherlands Department of Otorhinolaryngology Leiden University Medical center LeidenThe Netherlands Department of Pathology Leiden University Medical CenterLeidenThe Netherlands

cD4^(+)T cells can"help"or"license" conventional type 1 dendritic cells(cDc1s)to induce cD8^(+)cytotoxic T lymphocyte(cTL)anticancer responses,as proven in mouse *** recently identified cDc1s with a transcriptomic imprint of cD4^(+)T-cell help,specifically in T-cell-infiltrated human cancers,and these cells were associated with a good prognosis and response to PD-1-targeting ***,we delineate the mechanism of cDc1 licensing by cD4^(+)T cells in *** cD4^(+)T cells produce IFNβvia the STING pathway,which promotes MHc-I antigen(cross-)presentation by cDc1s and thereby improves their ability to induce cTL anticancer *** cooperation with cD40 ligand(L),IFNβalso optimizes the costimulatory and other functions of cDc1s required for cTL response ***-I-producing cD4^(+)T cells are present in diverse T-cell-infiltrated cancers and likely deliver“help”signals to cTLs locally,according to their transcriptomic profile and colocalization with“helped/licensed”cDcs and tumor-reactive cD8^(+)T *** agreement with this scenario,the presence of IFN-I-producing cD4^(+)T cells in the TME is associated with overall survival and the response to PD-1 checkpoint blockade in cancer patients.

关键词： cD4^(+)T-cell help cDc1 licensing IFN-I signaling cD40 costimulation (cross-)presentation cTL priming Tumor control

Photoionisation detection of a single Er3+ ion with sub-100-ns time resolution

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National Science Review 2024年第4期11卷 38-45页

作者： Yangbo Zhang Wenda Fan jiliang Yang Hao Guan Qi Zhang Xi Qin changkui Duan Gabriele G.de Boo Brett c.johnson jeffrey c.Mc callum Matthew j.Sellars Sven Rogge chunming Yin jiangfeng Du cAS Key Laboratory of Microscale Magnetic Resonance and School of Physical Sciences University of Science and Technology of China cAS center for Excellence in Quantum Information and Quantum Physics University of Science and Technology of China Hefei National Laboratory University of Science and Technology of China centre of Excellence for Quantum computation and communication Technology School of Physics University of New South Wales centre of Excellence for Quantum computation and communication Technology School of Engineering RMIT University centre of Excellence for Quantum computation and communication Technology School of Physics University of Melbourne centre of Excellence for Quantum computation and communication Technology Research School of Physics and Engineering Australian National University

Efficient detection of single optical centres in solids is essential for quantum information processing, sensing and single-photon generation *** this work,we use radio-frequency（RF） reflectometry to electrically detect the photoionisation induced by a single Er3+ion in *** high bandwidth and sensitivity of the RF reflectometry provide sub-100-ns time resolution for the photoionisation *** this technique,the optically excited state lifetime of a single Er3+ion in a Si nano-transistor is measured for the first time to be 0.49±0.04μ*** results demonstrate an efficient approach for detecting a charge state change induced by Er excitation and *** approach could be used for fast readout of other single optical centres in solids and is attractive for large-scale integrated optical quantum systems thanks to the multi-channel RF reflectometry demonstrated with frequency multiplexing techniques.

关键词： single optical centres erbium ions RF reflectometry photoionisation detection

Music alters heart rate and psychological responses but not muscle activation during light-intensity isometric exercise

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Sports Medicine and Health Science 2024年第4期6卷 394-401页

作者： Andrew R.Moore jasmin c.Hutchinson christa Winter Paul c.Dalton Lori A.Bolgla Vincent j.Paolone Department of Kinesiology Augusta University112015th St.AugustaGA30912USA Department of Exercise Science&Athletic Training Springfield College263 Alden St.SpringfieldMA01109USA Department of Psychology Springfield College263 Alden St.SpringfieldMA01109USA Heart&Vascular Institute Penn State College of MedicinePenn State University500 HMC Crescent RoadNorth Lobby HersheyPA17033USA Department of Physical Therapy Augusta University112015th St.AugustaGA30912USA

Listening to music manipulates attention to be more externally focused,which has the potential to improve muscular *** study aimed to determine the effect of listening to music on muscle activation during an isometric exercise task,and compare this effect to those of other attentional focus *** healthy subjects(n=35;16 men/19 women)completed an isometric elbow flexion task for 1 min in three randomized and counterbalanced conditions:internal focus(INT),external focus with a simple distraction task(EXT),or listening to music(MUS).Muscle activation of the biceps and triceps brachii and heart rate(HR)were recorded throughout the exercise *** of perceived exertion(RPE),affective valence,and motivation were measured at the end of each *** was no difference in muscle activation measures among the three *** during MUS was lower than EXT at 15 s([89.4±11.8]beats/min vs.[93.1±12.9]beats/min;p=0.018)and 30 s([90.6±12.4]beats/min vs.[94.2±12.5]beats/min;p=0.026),and lower than INT at 60 s([93.3±13.3]beats/min vs.[96.7±12.0]beats/min;p=0.016).Overall RPE was higher for INT(13.4±2.2)than for MUS([12.6±2.0];p=0.020)and EXT([11.94±2.22];pctive valence was higher for MUS than for INT([2.7±1.4]vs.[2.1±1.5];p=0.011).Manipulating attentional focus did not alter muscle activation for a light-intensity isometric muscular endurance task,though MUS was reported as more positive and requiring less exertion to complete than *** music can therefore be recommended during light-intensity isometric exercise based on the psychological benefits observed.

关键词： Electromyography Attentional focus Rating of perceived exertion Elbow flexion

Multinuclear MR and MRI study of lithium-ion cells using a variable field magnet and a fixed frequency RF probe

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Magnetic Resonance Letters 2024年第1期4卷 10-20页

作者： Andrés Ramírez Aguilera Florin Marica Kevin j.Sanders Md Al Raihan c.Adam Dyker Gillian R.Goward Bruce *** UNB MRI centre Department of PhysicsUniversity of New BrunswickFrederictonNew BrunswickE3B 5A3Canada Department of chemistry McMaster UniversityHamiltonOntarioL8S 4L8Canada Department of chemistry University of New BrunswickFrederictonNew BrunswickE3B 5A3Canada

An exploratory multinuclear magnetic resonance(MR)and magnetic resonance imaging(MRI)study was performed on lithium-ion battery cells with ^(7)Li,^(19)F,and ^(1)H measurements.A variable field superconducting magnet with a fixed frequency parallel-plate radiofrequency(RF)probe was employed in the *** magnetic field was changed to set the resonance frequency of each nucleus to the fixed RF probe frequency of 33.7 *** cartridge-like lithium-ion cells,with graphite anodes and LiNi_(0.5)Mn_(0.3)co_(0.2)O_(2)(NMc)cathodes,were *** cell was pristine,and one was charged to a cell voltage of 4.2 *** results presented demonstrate the great potential of the variable field magnet approach in multinuclear measurement of lithium-ion *** methods open the door for developing faster and simpler methods for detecting,quantifying,and interpreting MR and MRI data from lithium-ion and other batteries.

关键词： Multinuclear MR/MRI Variable field magnet Lithium-ion battery Parallel-plate rf probe

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Enhancing 3D Reconstruction Accuracy of FIB Tomography Data Using Multi‑voltage Images and Multimodal Machine Learning

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Nanomanufacturing and Metrology 2024年第1期7卷 48-60页

作者： Trushal Sardhara Alexander Shkurmanov Yong Li Lukas Riedel Shan Shi christian j.cyron Roland c.Aydin Martin Ritter Institute for continuum and Material Mechanics Hamburg University of TechnologyHamburgGermany Electron Microscopy Unit Hamburg University of TechnologyHamburgGermany Institute of Materials Physics and Technology Hamburg University of TechnologyHamburgGermany Institute of Materials Mechanics Helmholtz-Zentrum HereonGeesthachtGermany Research Group of Integrated Metallic Nanomaterials Systems Hamburg University of TechnologyHamburgGermany Institute of Material Systems Modeling Helmholtz-Zentrum HereonGeesthachtGermany

FIB-SEM tomography is a powerful technique that integrates a focused ion beam(FIB)and a scanning electron microscope(SEM)to capture high-resolution imaging data of *** approach involves collecting in-plane SEM imagesand using FIB to remove material layers for imaging subsequent planes,thereby producing image ***,theseimage stacks in FIB-SEM tomography are subject to the shine-through effect,which makes structures visible from theposterior regions of the current *** artifact introduces an ambiguity between image intensity and structures in thecurrent plane,making conventional segmentation methods such as thresholding or the k-means algorithm *** study,we propose a multimodal machine learning approach that combines intensity information obtained at differentelectron beam accelerating voltages to improve the three-dimensional(3D)reconstruction of *** treatingthe increased shine-through effect at higher accelerating voltages as a form of additional information,the proposed methodsignificantly improves segmentation accuracy and leads to more precise 3D reconstructions for real FIB tomography data.

关键词： Multimodal machine learning Multi-voltage images FIB-SEM Overdeterministic systems 3D reconstruction FIB tomography

A detailed comparison of the composition of(RE)-Ba-cu-O-Ag bulk superconductors

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Superconductivity 2024年第1期9卷 87-94页

作者： j.V.j.congreve Y.Shi A.R.Dennis H.Druiff N.c.Tutt D.A.cardwell j.H.Durrell Department of Engineering University of CambridgeCambridgeUK

The homogeneity of the microstructure and composition are critical in determining the properties of rare earthbarium‐cuprate,single grain bulk superconductors[(RE)BcO].The magnitude of the trapped magnetic field achieveable in these technologically important materials,in particular,is influenced heavily by the size and distribution of(RE)_(2)BacuO_(x)(RE‐211)flux pinning inclusions in the bulk microstructure,whereas the size and distribution of silver agglomerates present within the bulk superconducting matrix correlate directly with improved mechanical *** careful engineering,these materials have significant potential for application in range of devices related to energy storage,medicine,electro‐magnetic machinery and microelectronic *** of(RE)BcO bulk superconductors typically involves heating a powder compact above its peritectic decomposition temperature followed by slow cooling to facilitate the growth of a single ***(RE)BcO composition has a different peritectic temperature and growth rate,which,therefore,necessitates different requirements in the heating *** fabrication temperature and growth rate,for example,may have an effect on the RE‐211 and silver distribution,which may,in turn,affect the superconducting properties of the resulting single *** this work we compare the distributions of silver and RE‐211 in the single grain microstructures of YBcOAg,GdBcO‐Ag,EuBcO‐Ag and SmBcO‐Ag bulk superconductors using optical microscopy,scanning electron microscopy and energy dispersive X‐ray *** observe that the distributions are very similar along both the a/b‐axis and c‐axis of these *** suggests that factors other than the maximum temperature used to achieve peritectic decomposition and the rate of single grain growth are particularly influential in determining the properties of the as‐processed samples in the top seeded melt growth *** observation demonstrates there is freedom to us

关键词： YBcO‐Ag GdBcO‐Ag SmBcO‐Ag EuBcO‐Ag composition Bulk superconductor

Light sheet microscope scanning of biointegrated microlasers for localized refractive index sensing

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Photonics Research 2024年第8期12卷 1673-1680页

作者： ROSS c.cOWIE MARcEL ScHUBERT SUPA School of Physics and AstronomyUniversity of St AndrewsSt AndrewsUK Humboldt centre for Nano and Biophotonics Department of ChemistryUniversity of CologneCologneGermany

Whispering gallery mode(WGM)microlasers are highly sensitive to localized refractive index changes allowing to link their emission spectrum to various chemical,mechanical,or physical *** recently found applications in biological studies within single cells,in three-dimensional samples such as multicellular spheroids,or in ***,detailed studies of biological samples also need to account for the structural heterogeneity of tissues and live animals,therefore requiring a combination of high-resolution microscopy and laser ***,we design and construct a light sheet fluorescence microscope with a coupled spectrometer for use in microlaser studies for combined high-resolution,high-speed imaging and WGM spectral *** light sheet illumination profile and the decoupled geometry of excitation and emission hereby directly affect the lasing and sensing properties,mainly through geometric constraints and by light coupling *** demonstrate the basic working principle of microlaser spectroscopy under light sheet excitation and measure the absolute refractive index within agarose and in zebrafish tail muscle *** further analyze the light coupling conditions that lead to the occurrence of two separate oscillation *** so-called cross modes can be scanned around the entire microlaser surface,which allows to estimate a surface-averaged refractive index profile of the microlaser environment.

关键词： refractive index excitation

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