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Hybridizing collective spin excitations and a cavity with high cooperativity provides a new research subject in the field of cavity quantum electrodynamics and can also have potential applications to quantum information. Here we report an experimental study of cavity quantum electrodynamics with ferromagnetic magnons in a small yttrium-iron-garnet (YIG) sphere at both cryogenic and room temperatures. We observe for the first time a strong coupling of the same cavity mode to both a ferromagnetic-resonance (FMR) mode and a magnetostatic (MS) mode near FMR in the quantum limit. This is achieved at a temperature ~22 mK, where the average microwave photon number in the cavity is less than one. At room temperature, we also observe strong coupling of the cavity mode to the FMR mode in the same YIG sphere and find a slight increase of the damping rate of the FMR mode. These observations reveal the extraordinary robustness of the FMR mode against temperature. However, the MS mode becomes unobservable at room temperature in the measured transmission spectrum of the microwave cavity containing the YIG sphere. Our numerical simulations show that this is due to a drastic increase of the damping rate of the MS mode. Quantum electrodynamics: Physics with a crystal ball New research unveils quantum-coherence properties of ferromagnetic magnons in a magnetic sphere at both cryogenic and room temperatures. Tie-Fu Li and J. Q. You from the Beijing Computational Science Research Center, along with collaborators in China, Japan and the USA, placed a submillimeter yttrium-iron-garnet (YIG) sphere within a three-dimensional microwave cavity. They observed a strong interaction between the ferromagnetic resonances of the small magnetic sphere and photons in the surrounding cavity, and confirmed that single photons in the cavity showed strong and robust coupling with the collective spin excitations of magnetic YIG. The coupling extended from cryogenic temperatures up to room temperature, emphasizing the considerable practical potential of this system. These findings remind us that the interaction of different quantum systems can lead to properties unknown to classical systems, revealing potential practical applications.

A relative complete set of He I 10830 Aa profiles and their coincident slit-jaw H alpha images of the large limb flare (2N/X20) of 16 August 1989 were observed by the solar spectrograph at Purple Mountain Observatory. In addition to the unusually broadened spectral profiles observed in the impulsive phase, more than half of the observed He I 10830 Aa profiles are characterized by central reversals, which were detected not only in the impulsive phase but also in the late decaying phase. The central-reversed profiles may exist at different heights, ranging from the solar limb to (3-4) x 10 super(4) km above. The absorption varies with time and position, with a typical lifetime and size of several minutes and 5-6 arc sec, respectively. Depths of the absorption profiles also change clearly. The absorptions are usually deeper at the loop footpoint near the solar limb and shallower at loop-top. However, the most unusual feature is that all the line-center wavelengths of them show no shift relative to that of the quiet chromosphere near the limb, implying the apparent velocities are zero while the associated emission profiles have different apparent velocities. Theoretical simulations demonstrate that the Doppler widths of the absorptions are in the range of (0.35-0.5)Aa and increase with height, and the source functions are (0.11-0.3) times the disk center intensity. However, the absorptions have a relative large range of optical thickness (0.1-1.3) in the I sub(3) component of the He I 10830 Aa triplet. We have not observed such absorption in other limb flares, including the SB/X2.9 flare of 17 August 1989 that occurred in the same active region as the studied one (NOAA 5629). Our studies show that the absorption could not result from he scattering by the telluric atmosphere or from normal chromospheric absorption. This unique phenomenon may be related to extra intense X-ray flux and caused by diffuse and non uniform materials dissociated from the flare instead of self-absorption of the flare.

We obtained a complete set of Hα, Ca Π 8542 and He I 10830 spectra and slit-jaw Hα images of the C5.6 limb flare of 1 August 2003 using the Multi-channel Infrared Solar Spectrograph (MISS) at Purple Mountain Observatory. This flare was also observed by the Reuven Ramaty High-Energy Solar Spectroscopic Imager (RHESSI) and partially by the Extreme-ultraviolet Imaging Telescope (EIT) on SOHO. This flare underwent a rapid rising and expanding episode in the impulsive phase. All the Hα, Ca Π 8542 and He I 10830 profiles of the flare are rather wide and the widest profiles were observed in the middle bright part of the flare instead of at the flare loop top near the flare maximum. The flare manifested obvious rotation in the flare loop and the decrease of the rotation angular speed with time at the loop-top may imply a de-twisting process of the magnetic field. The significant increases of the Doppler widths of these lines in the impulsive phase reflect quick heating of the chromosphere, and rapid rising and expanding of the flare loop. The RHESSI observations give a thermal energy spectrum for this flare, and two thermal sources and no non-thermal source are found in the reconstructed RHESSI images. This presumably indicates that the energy transfer in this flare is mainly by heat conduction. The stronger thermal source is located near the solar limb with its position unchanged in the flare process and spatially coincident with the intense EUV and Hα emissions. The weaker one moved during the flare process and is located in the Hα dark cavities. This flare may support the theory of the magnetic reconnections in the lower solar atmosphere.[PUBLICATION ABSTRACT]

After carefully comparing the white-light (5600±00 Å) and the slit-jaw Hα images (0.5 Å passband) of the 2N/X20 white-light flare of 16 August 1989, we found that the Hα counterpart identification of the bright kernels in continuum by Hiei, Nakagomi, and Takuma (1992) was incorrect. Now we come to the conclusion that none of the two white-light kernels has a corresponding bright Hα area. Moreover, the loop shapes in white-light are also different from those in Hα. Hα loops rose more rapidly than white-light loops. However, their height-time variations on the whole are similar. This indicates that the continuum and chromospheric emissions of the flare presumably come from different plasmas, but may be modulated by some mutual factors, such as large-scale magnetic fields. Analysis of the Hei 10830 Å spectra taken simultaneously with the slit-jaw Hα images shows that the line-center intensity of Hei 10830 Å doesn't have a good correlation with the intensity of nearby continuum, which supports the above conclusions. In addition, the electron density at the white-light loop top estimated from the continuum around 5600 Å and 10830 Å is as high as 10^sup 12^-10^sup 13^ cm^sup -3^.[PUBLICATION ABSTRACT]

Since 1986, we have made some improvements to the multichannel solar spectrograph at Purple Mountain Observatory (PMO) step by step, and now we have developed and added to it a multichannel infrared imaging solar spectrograph. The original spectrograph can be used to observe simultaneously solar activity at 9 wave bands including Caii H and K line, Mgi b line, Hei D3 line and Ha through H!. The newly developed infrared imaging spectrograph can work in three wavelengths, i.e., Hei 10830 Aa, Caii 8542 Aa, and Ha. We replaced plates in the original system with CCDs and placed an image reducer before each CCD in order to match the CCD pixel size. The dispersions for Hei 10830 Aa, Caii 8542 Aa, and Ha of the new imaging solar spectrograph are 0.0693 Aa, 0.0767 Aa, and 0.0754 Aa per CCD pixel respectively, and each vertical CCD pixel represents 0.34 arc sec of solar disk. We can obtain the line-center and off-band intensities of the three lines and the intensities of continua adjacent to these lines through the new instrument. We can also acquire velocity maps and line profiles. Therefore, it is specially suitable for two-dimensional (2D) spectroscopic observations of solar flares and active regions. We carry out scanning observation by rotating the second mirror of the coelostat system. In this paper, we introduce the improvements we made and the new imaging solar spectrograph. Some observation results are also presented in this article.

The 3N/X3.3 flare of 28 November 1998 was observed in multiple wavelength simultaneously. The available data include Hα images, spectra in Hei 1083 nm and Caii 854.2 nm from Purple Mountain Observatory (PMO), soft X-ray (SXR) and hard X-ray (HXR) images and flux from Yohkoh. Morphological relationship investigation and spectral analysis of these data show: (1) The sudden brightening at loop top above the active region and the steep increase of SXR flux before flare onset suggest that the corona there had already been heated to some extent in the preflare phase. (2) The scales of the Caii 854.2 nm emission areas are very similar to those of the Hα line, but the emission profiles look like those of the Caii K line. Most of the Hei 1083 nm emissions exist in the bright Hα kernels and can last to the decay phase. (3) Flare spectra show that line shift and asymmetry are very common in this flare not only in the impulsive phase but also in the decay phase. The difference in the line shifts or asymmetry between Caii 854.2 nm and Hei 1083 nm, as well as the difference between the line center and wings of Caii 854.2 nm imply the existence of a velocity gradient in the line-of-sight direction. (4) Post-flare loops with very deep absorption ([asymptotically =]70%) and very-high-velocity red shifts (30-90 km s^sup -1^) were observed in Hei 1083 nm during the decay phase. However, only a slight dip can be found in the Caii 854.2 nm profile.[PUBLICATION ABSTRACT]

We obtained simultaneously He i 10830 Å spectra, Hα filtergrams and microwave data of a large limb flare (2N/X20) in 1989. In this paper we characterize He i 10830 spectra in relation to the impulsive phase. All the He i 10830 spectra, except those of the surge, show blue shift or blue asymmetry. The velocities inferred from the spectra range from a few to 160 km s-1, implying that the horizontal motion is very likely present in the structure of this flare at different heights. The He i 10830 profiles of a flare are relatively broad and cannot be simulated by the Doppler broadening mechanism with a uniform flare model atmosphere. It is most likely that these characteristics are related to rapid and localized heating in the low and middle chromosphere. Comparing the SXR and microwave data with the optical data leads to the following scenario: the corona was already heated to some extent before the flare onset, and in the first 2 minutes of the impulsive phase, heat conduction was the main source or, at least, a competitive source, for chromospheric heating. However, the impulsive event, associated with the unusually broadened He i 10830 line (Δλf>20 Å) and temporally correlated with a microwave burst, is probably caused by electron-beam heating.[PUBLICATION ABSTRACT]

After exposure to praziquantel in vitro at a concentration of 1 µg/ml for 0.5-2 hr, amounts of praziquantel in Schistosoma japonicum varied from 2.1 ± 1.2 to 3.7 ± 1.6 ng/male worm and 1.3 ± 1.2 to 2.2 ± 1.5 ng/female worm during the time studied. At 30 µ/ml, praziquantel amounts were 11-33-fold higher. However, within 2 hr after removal from a medium containing 30 µg/ml praziquantel, 95% of the drug was released from the parasites. When S. japonicum worm pairs were incubated in vitro with 1, 10, and 30 µg/ml of 4-hydroxypraziquantel, the major human oxidative metabolite of praziquantel, 0.2 ± 0.2, 3.8 ± 1.3, and 7.4 ± 1.3 ng/worm pair, respectively, were found after a 2-hr incubation, 15-30-fold lower than corresponding worm pair amounts of praziquantel. In vivo, when 4- or 5-wk S. japonicum-infected mice were treated orally with praziquantel (300 mg/kg), peak concentrations of praziquantel in plasma determined by high pressure liquid chromatography were 14.7 ± 1.5 µ/ml (4-wk infection) and 16.7 ± 2.8 µg/ml (5-wk infection) 15 min after treatment. Corresponding in vivo worm praziquantel amounts were 1.8 ± 0.4 ng/male worm and 2.4 ± 1.1 ng/female worm, respectively, in the 4-wk infection and 4.6 ± 1.6 ng/male worm and 5.6 ± 1.2 ng/female worm in the 5 -wk infection. Peak plasma concentrations of 4-hydroxypraziquantel were similar but corresponding in vivo worm amounts were 1-20-fold lower, depending on the time after drug administration. In S. japonicum, 4-hydroxypraziquantel was not formed from praziquantel in vitro, but the metabolite had similar pharmacologic effects on S. japonicum worms, e.g., contraction, and tegumental vesiculation, but at a 30-fold higher concentration of drug. Thus, it is unlikely that adequate plasma levels of metabolite are attained after appropriate doses of praziquantel to have a significant antischistosomal effect in S. japonicum-infected mice.

β-glucan, the most abundant fungal cell wall polysaccharide, has gained much attention from the scientific community in the last few decades for its fascinating but not yet fully understood immunobiology. Study of this molecule has been motivated by its importance as a pathogen-associated molecular pattern upon fungal infection as well as by its promising clinical utility as biological response modifier for the treatment of cancer and infectious diseases. Its immune effect is attributed to the ability to bind to different receptors expressed on the cell surface of phagocytic and cytotoxic innate immune cells, including monocytes, macrophages, neutrophils, and natural killer cells. The characteristics of the immune responses generated depend on the cell types and receptors involved. Size and biochemical composition of β-glucans isolated from different sources affect their immunomodulatory properties. The variety of studies using crude extracts of fungal cell wall rather than purified β-glucans renders data difficult to interpret. A better understanding of the mechanisms of purified fungal β-glucan recognition, downstream signaling pathways, and subsequent immune regulation activated, is, therefore, essential not only to develop new antifungal therapy but also to evaluate β-glucan as a putative anti-infective and antitumor mediator. Here, we briefly review the complexity of interactions between fungal β-glucans and mononuclear phagocytes during fungal infections. Furthermore, we discuss and present available studies suggesting how different fungal β-glucans exhibit antitumor and antimicrobial activities by modulating the biologic responses of mononuclear phagocytes, which make them potential candidates as therapeutic agents.

Mitochondrial disease associated with the pathogenic m.3243A>G variant is a common, clinically heterogeneous, neurogenetic disorder. Using multiple linear regression and linear mixed modelling, we evaluated which commonly assayed tissue (blood N  = 231, urine N  = 235, skeletal muscle N  = 77) represents the m.3243A>G mutation load and mitochondrial DNA (mtDNA) copy number most strongly associated with disease burden and progression. m.3243A>G levels are correlated in blood, muscle and urine ( R 2  = 0.61–0.73). Blood heteroplasmy declines by ~2.3%/year; we have extended previously published methodology to adjust for age. In urine, males have higher mtDNA copy number and ~20% higher m.3243A>G mutation load; we present formulas to adjust for this. Blood is the most highly correlated mutation measure for disease burden and progression in m.3243A>G‐harbouring individuals; increasing age and heteroplasmy contribute ( R 2  = 0.27, P  < 0.001). In muscle, heteroplasmy, age and mtDNA copy number explain a higher proportion of variability in disease burden ( R 2  = 0.40, P  < 0.001), although activity level and disease severity are likely to affect copy number. Whilst our data indicate that age‐corrected blood m.3243A>G heteroplasmy is the most convenient and reliable measure for routine clinical assessment, additional factors such as mtDNA copy number may also influence disease severity. Synopsis The m.3243A>G pathogenic mtDNA variant is associated with a highly heterogeneous multisystem disorder and varying mutation levels across tissues. In this study, mutation levels were characterised in three commonly sampled tissues ‐ blood, urine, skeletal muscle ‐ and correlated with disease burden. Urine m.3243A>G heteroplasmy levels display more variability than blood levels and must be corrected for a ˜20% lower level in females. Blood m.3243A>G heteroplasmy levels must be corrected for a decline of ˜2.3% per year. Disease burden and progression are more strongly associated with blood m.3243A>G heteroplasmy levels than urine levels. 27% of the variance in disease burden can be attributed to blood m.3243A>G heteroplasmy and age. Age, m.3243A>G heteroplasmy level and mtDNA copy number in skeletal muscle explain 40% of the variance in disease burden. Graphical Abstract The m.3243A>G pathogenic mtDNA variant is associated with a highly heterogeneous multisystem disorder and varying mutation levels across tissues. In this study, mutation levels were characterised in three commonly sampled tissues ‐ blood, urine, skeletal muscle ‐ and correlated with disease burden.