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Insect cuticle is critical for the environmental adaptability and insecticide resistance of insects. However, there is no clear understanding of the structure and protein components of the cuticle during each developmental stage of holometabolous insects, and knowledge about the protein components within each layer is vague. We conducted serial sectioning, cuticular structure analysis, and transcriptome sequencing of the larval, pupal, and adult cuticles of

An azulene modified iron porphyrin with a narrow bandgap is synthesized. When used as an electrocatalyst for CO2 reduction, it exhibits nearly 100% selectivity for carbon monoxide formation.

Alfvén waves as excited in black hole accretion disks and neutron star magnetospheres are the building blocks of turbulence in relativistic, magnetized plasmas. A large reservoir of magnetic energy is available in these systems, such that the plasma can be heated significantly even in the weak turbulence regime. We perform high-resolution three-dimensional simulations of counter-propagating Alfvén waves, showing that an $E_{B_{\perp }}(k_{\perp }) \propto k_{\perp }^{-2}$ energy spectrum develops as a result of the weak turbulence cascade in relativistic magnetohydrodynamics and its infinitely magnetized (force-free) limit. The plasma turbulence ubiquitously generates current sheets, which act as locations where magnetic energy dissipates. We show that current sheets form as a natural result of nonlinear interactions between counter-propagating Alfvén waves. These current sheets form owing to the compression of elongated eddies, driven by the shear induced by growing higher-order modes, and undergo a thinning process until they break-up into small-scale turbulent structures. We explore the formation of current sheets both in overlapping waves and in localized wave packet collisions. The relativistic interaction of localized Alfvén waves induces both Alfvén waves and fast waves, and efficiently mediates the conversion and dissipation of electromagnetic energy in astrophysical systems. Plasma energization through reconnection in current sheets emerging during the interaction of Alfvén waves can potentially explain X-ray emission in black hole accretion coronae and neutron star magnetospheres.

The silkworm Bombyx mori is a domestic insect for silk production and a lepidopteran model. The currently available genomes limit a full understanding of its genetic and phenotypic diversity. Here we assembled long-read genomes of 545 domestic and wild silkworms and constructed a high-resolution pan-genome dataset. We found that the silkworm population harbors extremely variable genomes containing 7,308 new gene families, 4,260 (22%) core gene families, and 3,432,266 non-redundant SVs. We deciphered a series of causal genes and variants associated with domestication, breeding, and ecological adaptation traits, and experimentally validated two of those genes using CRISPR-Cas9 or RNA interference. This unprecedented large-scale genomic resource allows for high-throughput screening of interesting traits for functional genomic research and breeding improvement of silkworms and may serve as a guideline for traits decoding in other species.

Samarium and neodymium co-doped ceria (Ce0.8Sm0.1Nd0.1O2−δ abbreviated SNDC) and lanthanum silicate (La9.33Si6O26 abbreviated LSO) composite electrolytes with different mixing ratio were prepared at 1500 and 1550 °C. The composite obtained were all with high density, and no chemical reaction between two phases was observed during sintering according to the XRD result. The addition of LSO has a great influence on the suppression of grain growth of SNDC, and brought about the change in conduction behavior of composite. High distortion at hetero interface has been observed by TEM. The composite with 30 wt% LSO exhibits the highest conductivity (0.0036 S/cm at 500 °C) with an improvement of 37% compared with SNDC. The measurement at low oxygen partial pressure demonstrated the high chemical stability of composite electrolyte, making it a promising candidate for intermediate temperature SOFCs or oxygen sensors.

The piggyBac (PB) transposon is the most widely used vector for generating transgenic silkworms. The stability of the PB transposon in the receptor is a serious concern that requires attention because of biosafety concerns. In this study, we found that the transgene silkworm developed loss of reporter gene traits. To further investigate the regularity, we traced the genes and traits of this silkworm. After successful alteration of the silkworm genome with the MASP1 gene (named red-eyed silkworm; RES), silkworm individuals with lost reporter genes were found after long-term transgenerational breeding and were designated as the white-eyed silkworm (WES). PCR amplification indicated that exogenous genes had been lost in the WES. Testing was conducted on the PB transposons, and the left arm (L arm) did not exist; however, the right arm (R arm) was preserved. Amino acid analysis showed that the amino acid content of the WES changed versus the common silkworm and RES. These results indicate that the migration of PB transposons in Bombyx mori does occur and is unpredictable. This is because the silkworm genome contains multiple PB-like sequences that might influence the genetic stability of transgenic lines. When using PB transposons as a transgene vector, it is necessary to fully evaluate and take necessary measures to prevent its re-migration in the recipient organism. Further experiments are needed if we want to clarify the regularity of the retransposition phenomenon and the direct and clear association with similar sequences of transposons.

The radio emission anomaly coincident with the 2016 glitch of the Vela pulsar may be caused by a star quake that launches Alfv\'{e}n waves into the magnetosphere, disturbing the original radio emitting region. To quantify the lifetime of the Alfv\'{e}n waves, we investigate a possible energy loss mechanism, the conversion of Alfv\'{e}nwaves into fast magnetosonic waves. Using axisymmetric force-free simulations, we follow the propagation of Alfv\'{e}n waves launched from the stellar surface with small amplitude into the closed zone of a force-free dipolar pulsar magnetosphere. We observe mode conversion happening in the ideal force-free regime. The conversion efficiency during the first passage of the Alfv\'{e}n wave through the equator can be large, for waves that reach large amplitudes as they travel away from the star, or propagate on the field lines passing close to the Y-point. However, the conversion efficiency is reduced due to dephasing on subsequent passages and considerable Alfv\'{e}n power on the closed field lines remains. Thus while some leakage into the fast mode happens, we need detailed understanding of the original quenching in order to say whether mode conversion alone can lead to reactivation of the pulsar on a short timescale., Comment: 14 pages, 14 figures, accepted for publication in ApJ

Using numerical simulations we show that low-amplitude Alfv\'en waves from a magnetar quake propagate to the outer magnetosphere and convert to "plasmoids" (closed magnetic loops) which accelerate from the star, driving blast waves into the magnetar wind. Quickly after its formation, the plasmoid becomes a thin relativistic pancake. It pushes out the magnetospheric field lines, and they gradually reconnect behind the pancake, generating a variable wind far stronger than the normal spindown wind of the magnetar. Repeating ejections drive blast waves in the amplified wind. We suggest that these ejections generate the simultaneous X-ray and radio bursts detected from SGR 1935+2154. A modest energy budget of the magnetospheric perturbation $\sim 10^{40}$ erg is sufficient to produce the observed bursts. Our simulation predicts a narrow (a few ms) X-ray spike from the magnetosphere, arriving almost simultaneously with the radio burst emitted far outside the magnetosphere. This timing is caused by the extreme relativistic motion of the ejecta., Comment: 8 pages, 5 figures, ApJL in press

The interfacial diffusion of yttrium stabilized zirconia (YSZ)‑samarium, neodymium co-doped ceria (SNDC) bilayer electrolyte has been systematically investigated by laser confocal micro Raman spectrometer. The bilayer structured electrolyte prepared using conventional sintering (CS) and spark plasma sintering (SPS) are well densified according to SEM measurement. Raman mapping clearly displayed the diffusion boundary of two layers by using the intensity of peak at 465 cm−1. We probed the concentration change of CeO2 across the interfacial region and figured out the diffusion thickness of specimens, based on the change of Raman spectroscopy at different positions. This result agrees quite well with the one obtained through EDS. The reliability of diffusion thickness on the sintering temperature and holding time was discussed according to Fick's law.

In some Seyfert Galaxies, the hard X-rays that produce fluorescent emission lines are thought to be generated in a hot corona that is compact and located at only a few gravitational radii above the supermassive black hole. We consider the possibility that this X-ray source may be powered by small scale magnetic flux tubes attached to the accretion disk near the black hole. We use three dimensional, time dependent force-free simulations in a simplified setting to study the dynamics of such flux tubes as they get continuously twisted by the central compact star/black hole. We find that, the dynamical evolution of the flux tubes connecting the central compact object and the accretion disk is strongly influenced by the confinement of the surrounding field. Although differential rotation between the central object and the disk tends to inflate the flux tubes, strong confinement from surrounding field quenches the formation of a jet-like outflow, as the inflated flux tube becomes kink unstable and dissipates most of the extracted rotational energy relatively close to the central object. Such a process may be able to heat up the plasma and produce strong X-ray emission. We estimate the energy dissipation rate and discuss its astrophysical implications., Comment: 16 pages, 17 figures. Accepted for publication in MNRAS

Recent modeling of Neutron Star Interior Composition Explorer(NICER) observations of the millisecond pulsar PSR J0030+0451 suggests that the magnetic field of the pulsar is non-dipolar. We construct a magnetic field configuration where foot points of the open field lines closely resemble the hotspot configuration from NICER observations. Using this magnetic field as input, we perform force-free simulations of the magnetosphere of PSR J0030+0451, showing the three-dimensional structure of its plasma-filled magnetosphere. Making simple and physically motivated assumptions about the emitting regions, we are able to construct the multi-wavelength lightcurves that qualitatively agree with the corresponding observations. The agreement suggests that multipole magnetic structures are the key to modeling this type of pulsars, and can be used to constrain the magnetic inclination angle and the location of radio emission., Comment: 9 pages, 5 figures, submitted to ApJL. Comments welcome!

There is observational evidence that the X-ray continuum source that creates the broad fluorescent emission lines in some Seyfert Galaxies may be compact and located at a few gravitational radii above the black hole. We consider the possibility that this compact source may be powered by small scale flux tubes near the black hole that are attached to the orbiting accretion disk. As a first step, this paper investigates the salient features of black hole magnetospheres that contain small scale, disk-hole linking "closed" flux tubes, using the force-free approximation in an axisymmetric setting. We find that the extent of the closed zone is a result of the balance between the black hole spin induced twist in the closed zone and the confinement pressure of the external (open) field of the disk. The maximal extent of the closed zone, for a typical external confinement, is usually a few gravitational radii. The pressure competition between the closed zone and the external confinement could in principle lead to interesting dynamics and dissipation relevant for the compact X-ray corona., 14 pages, 18 figures. Accepted for publication in MNRAS

In some low-luminosity accreting supermassive black hole systems, the supply of plasma in the funnel region can be a problem. It is believed that a local region with unscreened electric field can exist in the black hole magnetosphere, accelerating particles and producing high energy gamma-rays that can create $e^{\pm}$ pairs. We carry out time-dependent self-consistent 1D PIC simulations of this process, including inverse Compton scattering and photon tracking. We find a highly time-dependent solution where a macroscopic gap opens quasi-periodically to create $e^{\pm}$ pairs and high energy radiation. If this gap is operating at the base of the jet in M87, we expect an intermittency on the order of a few $r_g/c$, which coincides with the time scale of the observed TeV flares from the same object. For Sagittarius A* the gap electric field can potentially grow to change the global magnetospheric structure, which may explain the lack of a radio jet at the center of our galaxy., 3 figures, submitted to ApJL

First results are presented from kinetic numerical simulations of relativistic collisionless magnetic reconnection in pair plasma that include radiation reaction from both synchrotron and inverse Compton (IC) processes, motivated by non-thermal high-energy astrophysical sources, including in particular blazars. These simulations are initiated from a configuration known as 'ABC fields' that evolves due to coalescence instability and generates thin current layers in its linear phase. Global radiative efficiencies, instability growth rates, time-dependent radiation spectra, lightcurves, variability statistics and the structure of current layers are investigated for a broad range of initial parameters. We find that the IC radiative signatures are generally similar to the synchrotron signatures. The luminosity ratio of IC to synchrotron spectral components, the Compton dominance, can be modified by more than one order of magnitude with respect to its nominal value. For very short cooling lengths, we find evidence for modification of the temperature profile across the current layers, no systematic compression of plasma density, and very consistent profiles of E.B. We decompose the profiles of E.B with the use of the Vlasov momentum equation, demonstrating a contribution from radiation reaction at the thickness scale consistent with the temperature profile., Comment: 18 pages, 6 figures, accepted for publication in the Journal of Plasma Physics, special collection "Plasma physics under extreme conditions: from high-energy-density experiments to astrophysics", Eds. F. Fiuza, R. D. Blandford & S. Glenzer

Recent observations of the Crab Nebula (Rudy et al 2015) have maintained its reputation for high energy astrophysical enlightenment and its use as a testbed for theories of the behaviour of magnetized, relativistic plasma. In particular, new observations of the inner knot located 0.65" SE from the pulsar confirm that it is compact, elongated transversely to the symmetry axis and curved concave towards the pulsar. 60 percent polarization has been measured along the symmetry axis (Moran et al 2013). The knot does not appear to be involved in the gamma ray flares. The new observations both reinforce the interpretation of the knot as dissipation of the pulsar wind at a strong shock and challenge the details of existing models of this process. In particular, it is argued that the compactness, high polarization and curvature are difficult to reconcile with simple relativistic shock models. Alternative possibilities include deflection of the outflow ahead of the shock and spatial variation in which the knot is interpreted as a caustic. Some future observations are proposed and new theoretical investigations are suggested., 17 pages, 13 figures. Published in MNRAS

In this contribution we review the recent progress in the modeling of Pulsar Wind Nebulae (PWN). We start with a brief overview of the relevant physical processes in the magnetosphere, the wind-zone and the inflated nebula bubble. Radiative signatures and particle transport processes obtained from 3D simulations of PWN are discussed in the context of optical and X-ray observations. We then proceed to consider particle acceleration in PWN and elaborate on what can be learned about the particle acceleration from the dynamical structures called "wisps" observed in the Crab nebula. We also discuss recent observational and theoretical results of gamma-ray flares and the inner knot of the Crab nebula, which had been proposed as the emission site of the flares. We extend the discussion to GeV flares from binary systems in which the pulsar wind interacts with the stellar wind from a companion star. The chapter concludes with a discussion of solved and unsolved problems posed by PWN., To appear in "Jets and Winds in Pulsar Wind Nebulae, Gamma-ray Bursts and Blazars: Physics of Extreme Energy Release" of the Space Science Reviews series. The final publication is available at Springer via http://dx.doi.org/10.1007/s11214-017-0344-x

Inverse Compton-pair cascades are initiated when gamma-rays are absorbed on an ambient soft photon field to produce relativistic pairs, which in turn up-scatter the same soft photons to produce more gamma-rays. If the Compton scatterings take place in the deep Klein-Nishina regime, then triplet pair production ($e\gamma_b \rightarrow ee^{+}e^{-}$) becomes relevant and may even regulate the development of the cascade. We investigate the properties of pair-Compton cascades with triplet pair production in accelerating gaps, i.e., regions with an unscreened electric field. Using the method of transport equations for the particle evolution, we compute the growth rate of the pair cascade as a function of the accelerating electric field in the presence of black-body and power-law ambient photon fields. Informed by the numerical results, we derive simple analytical expressions for the peak growth rate and the corresponding electric field. We show that for certain parameters, which can be realized in the vicinity of accreting supermassive black holes at the centers of active galactic nuclei, the pair cascade may well be regulated by inverse Compton scattering in the deep Klein-Nishina regime and triplet pair production. We present indicative examples of the escaping gamma-ray radiation from the gap, and discuss our results in application to the TeV observations of radio galaxy M87., Comment: 12 pages, 6 figures, accepted for publication in ApJ

The source of metasilicate in mineral water of Jingyu County. located in Changbai Mountains of northeastern China, was analysed through two groups of water-rock interaction experiments. One is a hydrolysis immersion experiment using basalt and the other is an immersion experiment utilizing a mixture of soil, scoria, and clastic basalt under the same conditions. Results indicate that the metasilicate in mineral water is mainly derived from the hydrolysis of silicates and silica in the basalt, scoria, and soil. In the first immersion experiment, the release of metasilicate is linear, with dissolved metasilicate increasing continuously through time at a stable release rate of about 0.01 mg/(kg·day). The second experiment indicates that the contribution of soil and scoria to metasilicate in mineral water is higher than that of clastic basalt under the same conditions.

On 2015 June 16, Fermi-LAT observed a giant outburst from the flat spectrum radio quasar 3C 279 with a peak $>100$ MeV flux of $\sim3.6\times10^{-5}\;{\rm photons}\;{\rm cm}^{-2}\;{\rm s}^{-1}$ averaged over orbital period intervals. It is the historically highest $\gamma$-ray flux observed from the source including past EGRET observations, with the $\gamma$-ray isotropic luminosity reaching $\sim10^{49}\;{\rm erg}\;{\rm s}^{-1}$. During the outburst, the Fermi spacecraft, which has an orbital period of 95.4 min, was operated in a special pointing mode to optimize the exposure for 3C 279. For the first time, significant flux variability at sub-orbital timescales was found in blazar observations by Fermi-LAT. The source flux variability was resolved down to 2-min binned timescales, with flux doubling times less than 5 min. The observed minute-scale variability suggests a very compact emission region at hundreds of Schwarzschild radii from the central engine in conical jet models. A minimum bulk jet Lorentz factor ($\Gamma$) of 35 is necessary to avoid both internal $\gamma$-ray absorption and super-Eddington jet power. In the standard external-radiation-Comptonization scenario, $\Gamma$ should be at least 50 to avoid overproducing the synchrotron-self-Compton component. However, this predicts extremely low magnetization ($\sim5\times10^{-4}$). Equipartition requires $\Gamma$ as high as 120, unless the emitting region is a small fraction of the dissipation region. Alternatively, we consider $\gamma$ rays originating as synchrotron radiation of $\gamma_{\rm e}\sim1.6\times10^6$ electrons, in magnetic field $B\sim1.3$ kG, accelerated by strong electric fields $E\sim B$ in the process of magnetoluminescence. At such short distance scales, one cannot immediately exclude production of $\gamma$ rays in hadronic processes., Comment: 8 pages, 4 figures. Accepted for publication in ApJ Letter. --Corresponding authors: Masaaki Hayashida (mahaya_at_icrr.u-tokyo.ac.jp), Greg Madejski (madejski_at_slac.stanford.edu), and Krzysztof Nalewajko (knalew_at_camk.edu.pl)

In order to understand the conditions which lead a highly magnetized, relativistic plasma to become unstable, and in such cases how the plasma evolves, we study a prototypical class of magnetostatic equilibria where the magnetic field satisfies $\nabla \times\mathbf B = \alpha \mathbf B$, where $\alpha$ is spatially uniform, on a periodic domain. Using numerical solutions we show that generic examples of such equilibria are unstable to ideal modes (including incompressible ones) which are marked by exponential growth in the linear phase. We characterize the unstable mode, showing how it can be understood in terms of merging magnetic and current structures, and explicitly demonstrate its instability using the energy principle. Following the nonlinear evolution of these solutions, we find that they rapidly develop regions with relativistic velocities and electric fields of comparable magnitude to the magnetic field, liberating magnetic energy on dynamical timescales and eventually settling into a configuration with the largest allowable wavelength. These properties make such solutions a promising setting for exploring the mechanisms behind extreme cosmic sources of gamma rays., Comment: 5 pages, 4 figures + 6 pages supplemental material; revised to match version accepted by PRL; for associated movies see http://youtu.be/EPY_yx7H3_Q and http://youtu.be/Umww9oh08C8

Monthly notices of the Royal Astronomical Society 446(1), 205 - 216 (2015). doi:10.1093/mnras/stu2025, We present new Jansky Very Large Array (VLA) radio images of the Crab nebula at 5.5 GHz, taken at two epochs separated by 6 d about 2 months after a gamma-ray flare in 2012 July. We find no significant change in the Crab's radio emission localized to a region of, Published by Oxford Univ. Press, Oxford

Physicists have pondered the origin of cosmic rays for over a hundred years. However the last few years have seen an upsurge in the observation, progress in the theory and a genuine increase in the importance attached to the topic due to its intimate connection to the indirect detection of evidence for dark matter. The intent of this talk is to set the stage for the meeting by reviewing some of the basic features of the entire cosmic ray spectrum from GeV to ZeV energy and some of the models that have been developed. The connection will also be made to recent developments in understanding general astrophysical particle acceleration in pulsar wind nebulae, relativistic jets and gamma ray bursts. The prospects for future discoveries, which may elucidate the origin of cosmic rays, are bright., Comment: 14 pages, 10 figures, to appear in Proceedings of the "Cosmic Ray Origin - Beyond the Standard Models" International Conference, Nuclear Physics B Proceedings Supplement. Eds. O. Tibolla, L. Drury, M. Persic, S. Kaufmann, H. V\"olk, K. Mannheim and A. de Angelis

We present the results of particle-in-cell numerical pair plasma simulations of relativistic 2D magnetostatic equilibria known as the 'ABC' fields. In particular, we focus on the lowest-order unstable configuration consisting of two minima and two maxima of the magnetic vector potential. Breaking of the initial symmetry leads to exponential growth of the electric energy and to the formation of two current layers, which is consistent with the picture of 'X-point collapse' first described by Syrovatskii. Magnetic reconnection within the layers heats a fraction of particles to very high energies. After the saturation of the linear instability, the current layers are disrupted and the system evolves chaotically, diffusing the particle energies in a stochastic second-order Fermi process leading to the formation of power-law energy distributions. The power-law slopes harden with the increasing mean magnetization, but they are significantly softer than those produced in simulations initiated from Harris-type layers. The maximum particle energy is proportional to the mean magnetization, which is attributed partly to the increase of the effective electric field and partly to the increase of the acceleration time scale. We describe in detail the evolving structure of the dynamical current layers, and report on the conservation of magnetic helicity. These results can be applied to highly magnetized astrophysical environments, where ideal plasma instabilities trigger rapid magnetic dissipation with efficient particle acceleration and flares of high-energy radiation., 12 pages, 12 figures, submitted to ApJ

Objective Vitamin A deficiency is associated with an increased incidence of infectious respiratory and alimentary tract diseases in children, and vitamin A supplementation can prevent and assist in treating these diseases. To clarify the mechanisms of these associations, we investigated the effects of vitamin A deficiency on mucosal immunity to intestinal infection in rats. Methods Specific pathogen-free Sprague-Dawley rats received a vitamin A-free diet, with ( n = 20) or without ( n = 20) vitamin A supplementation. Intestinal infection was induced by oral inoculation of salmonella in 10 rats in each group. The rats were killed 3 d after infection was induced, and we measured the number, maturation, and activation of dendritic cells; the expression of Toll-like receptors 2 and 4; mRNA level of myeloid differentiation primary response gene (88) (MyD88, pattern-recognition receptors and their adapter protein); immune cytokine production in the intestinal mucosa; and the amount of secretory immunoglobulin A in the gut. Results In vitamin-A deficient rats, the number of mucosal dendritic cells and the production of IL-12 markedly increased; the mucosal expressions of Toll-like receptor 2 and MyD88 were up-regulated, and secretions of interferon-γ and secretory immunoglobulin A were decreased. Infection aggravated the damage to the intestinal mucosa and lowered immunity in vitamin-A deficient rats. Conclusion Vitamin A deficiency damaged both humoral and cellular immunity in the mucosa. Modulation of dendritic cells is likely an important mechanism through which vitamin A deficiency affects mucosal immune responses against infection.

One of the most intriguing results from the gamma-ray instruments in orbit has been the detection of powerful flares from the Crab Nebula. These flares challenge our understanding of pulsar wind nebulae and models for particle acceleration. We report on the portion of a multiwavelength campaign using Keck, HST, and Chandra concentrating on a small emitting region, the Crab's inner knot, located a fraction of an arcsecond from the pulsar. We find that the knot's radial size, tangential size, peak flux, and the ratio of the flux to that of the pulsar are correlated with the projected distance of the knot from the pulsar. A new approach, using singular value decomposition for analyzing time series of images, was introduced yielding results consistent with the more traditional methods while some uncertainties were substantially reduced. We exploit the characterization of the knot to discuss constraints on standard shock-model parameters that may be inferred from our observations assuming the inner knot lies near to the shocked surface. These include inferences as to wind magnetization, shock shape parameters such as incident angle and poloidal radius of curvature, as well as the IR/optical emitting particle enthalpy fraction. We find that while the standard shock model gives good agreement with observation in many respects, there remain two puzzles: (a) The observed angular size of the knot relative to the pulsar--knot separation is much smaller than expected; (b) The variable, yet high degree of polarization reported is difficult to reconcile with a highly relativistic downstream flow., Comment: 46 pages, 14 figures, submitted to the Astrophysical Journal

We report on observations of the supernova remnant Cassiopeia A in the energy range from 100 MeV to 100 GeV using 44 months of observations from the Large Area Telescope on board the Fermi Gamma-Ray Space Telescope. We perform a detailed spectral analysis of this source and report on a low-energy break in the spectrum at GeV. By comparing the results with models for the gamma-ray emission, we find that hadronic emission is preferred for the GeV energy range.