Mukai’s program in [16] seeks to recover a K3 surface X from any curve C on it by exhibiting it as a Fourier–Mukai partner to a Brill–Noether locus of vector bundles on the curve. In the case X has Picard number one and the curve $C\in |H|$ is primitive, this was confirmed by Feyzbakhsh in [11, 13] for $g\geq 11$ and $g\neq 12$. More recently, Feyzbakhsh has shown in [12] that certain moduli spaces of stable bundles on X are isomorphic to the Brill–Noether locus of curves in $|H|$ if g is sufficiently large. In this paper, we work with irreducible curves in a nonprimitive ample linear system $|mH|$ and prove that Mukai’s program is valid for any irreducible curve when $g\neq 2$, $mg\geq 11$ and $mg\neq 12$. Furthermore, we introduce the destabilising regions to improve Feyzbakhsh’s analysis in [12]. We show that there are hyper-Kähler varieties as Brill–Noether loci of curves in every dimension.

In this paper, we study the rapid transition in Richtmyer–Meshkov instability (RMI) with reshock through three-dimensional double-layer swirling vortex rings. The rapid transition in RMI with reshock has an essential influence on the evolution of supernovas and the ignition of inertial confinement fusion, which has been confirmed in numerical simulations and experiments in shock-tube and high-energy-density facilities over the past few years. Vortex evolution has been confirmed to dominate the late-time nonlinear development of the perturbed interface. However, few studies have investigated the three-dimensional characteristics and nonlinear interactions among vortex structures during the transition to turbulent flows. The coexistence of co-rotating and counter-rotating vortices is hypothesized to induce successive large-scale strain fields, which are the main driving sources for rapid development. The three-dimensional effect is reflected in the presence of local swirling motion in the azimuthal direction, and it decreases the translation velocity of a vortex ring. Large-, middle- and small-scale strain fields are employed to describe the development process of RMI with reshock, e.g. vorticity deposited by the reshock, formation of the coexistence of the co-rotating and counter-rotating vortices, iterative cascade under the amplification of the strain fields and viscous dissipation to internal energy. This provides theoretical suggestions for designing practical applications, such as the estimation of the hydrodynamic instability and mixing during the late-time acceleration phase of the inertial confinement fusion.

We propose a 2.1 μm high-energy dissipative soliton resonant (DSR) fiber laser system based on a mode-locked seed laser and dual-stage amplifiers. In the seed laser, the nonlinear amplifying loop mirror technique is employed to realize mode-locking. The utilization of an in-band pump scheme and long gain fiber enables effectively exciting 2.1 μm pulses. A section of ultra-high numerical aperture fiber (UHNAF) with normal dispersion and high nonlinearity and an output coupler with a large coupling ratio are used to achieve a high-energy DSR system. By optimizing the UHNAF length to 55 m, a 2103.7 nm, 88.1 nJ DSR laser with a 3-dB spectral bandwidth of 0.48 nm and a pulse width of 17.1 ns is obtained under a proper intracavity polarization state and pump power. The output power and conversion efficiency are 0.233 W and 4.57%, respectively, both an order of magnitude higher than those of previously reported holmium-doped DSR seed lasers. Thanks to the high output power and nanosecond pulse width of the seed laser, the average power of the DSR laser is linearly scaled up to 50.4 W via a dual-stage master oscillator power amplifier system. The 3-dB spectral bandwidth broadens slightly to 0.52 nm, and no distortion occurs in the amplified pulse waveform. The corresponding pulse energy reaches 19.1 μJ, which is the highest pulse energy in a holmium-doped mode-locked fiber laser system to the best of our knowledge. Such a 2.1 μm, high-energy DSR laser with relatively wide pulse width has prospective applications in mid-infrared nonlinear frequency conversion.

O’Grady’s generalised Franchetta conjecture (GFC) is concerned with codimension 2 algebraic cycles on universal polarised K3 surfaces. In [4], this conjecture has been studied in the Betti cohomology groups. Following a suggestion of Voisin, we investigate this problem in the Deligne-Beilinson (DB) cohomology groups. In this paper, we develop the theory of Deligne-Beilinson cohomology groups on (smooth) Deligne-Mumford stacks. Using the automorphic cohomology group and Noether-Lefschetz theory, we compute the 4th DB-cohomology group of universal oriented polarised K3 surfaces with at worst an $A_1$ -singularity and show that GFC for such family holds in DB-cohomology. In particular, this confirms O’Grady’s original conjecture in DB cohomology.

We identify the perverse filtration of a Lagrangian fibration with the monodromy weight filtration of a maximally unipotent degeneration of compact hyper-Kähler manifolds.

In the Galactic center, there are many massive stars blowing strong stellar winds, which will strongly influence the surrounding environment and even the Galactic feedback. The Galactic center is quiescent at present, so the unique continuous energy input source is the massive star, consequently giving rise to many special features, such as the radio bubbles, the X-ray chimneys, the non-thermal filaments and high-metallicity abundance. However, it is difficult to quantify their contributions due to the complex environment in this region, and the past supernovae and Sgr A* activity are also important factors shaping these features. In this work, we discuss some structures possibly related to the stellar winds and perform preliminary simulations to study their evolution. We conclude the stellar winds can obviously influence a large scale ∼ 100 pc, and can possibly influence a larger scale environment indirectly.

Ketosis is a metabolic disease of dairy cows often characterized by high concentrations of ketone bodies and fatty acids, but low milk protein and milk production. The Janus kinase 2 (JAK2)-signal transducer and activator of transcription 5 (STAT5) and the mechanistic target of rapamycin (mTOR) signaling pathways are central for the regulation of milk protein synthesis. The effect of high levels of fatty acids on these pathways and β-casein synthesis are unknown in dairy cows with clinical ketosis. Mammary gland tissue and blood samples were collected from healthy (n = 15) and clinically-ketotic (n = 15) cows. In addition, bovine mammary epithelial cells (BMEC) were treated with fatty acids, methionine (Met) or prolactin (PRL), respectively. In vivo, the serum concentration of fatty acids was greater (P > 0.05) and the percentage of milk protein (P > 0.05) was lower in cows with clinical ketosis. The JAK2-STAT5 and mTOR signaling pathways were inhibited and the abundance of β-casein was lower in mammary tissue of cows with clinical ketosis (P > 0.05). In vitro, high levels of fatty acids inhibited the JAK2-STAT5 and mTOR signaling pathways (P > 0.05) and further decreased the β-casein synthesis (P > 0.05) in BMEC. Methionine or PRL treatment, as positive regulators, activated the JAK2-STAT5 and mTOR signaling pathways to increase the β-casein synthesis. Importantly, the high concentration of fatty acids attenuated the positive effect of Met or PRL on mTOR, JAK2-STAT5 pathways and the abundance of β-casein (P > 0.05). Overall, these data indicate that the high concentrations of fatty acids that reach the mammary cells during clinical ketosis inhibit mTOR and JAK2-STAT5 signaling pathways, and further suppress β-casein synthesis.

As a giant compact filamentary cloud, Orion A has a similar morphology with those more distant filaments in infrared dark clouds as revealed in Herschel surveys. We compared their core mass functions and found a similar power law index of N(>m)∝ m−1.0 for the high-mass end, which may possibly indicates a common case for massive filamentary clouds. We also show that the measured mass function for a certain cloud would largely depend on its distance, thus call for caution in interpreting individual measurements of CMF.

At room temperature (RT), Fe2Mo3O12 is stable in monoclinic structure phase and above 780 K it transforms to an orthorhombic phase. Experiment shows that in the high temperature orthorhombic phase, the material exhibits low or negative thermal expansion property. In the paper, new compounds with the formula Fe2–x(ZrMg)0.5xMo3O12 (x = 0–1.8) are reported. The compounds are designed and synthesized to reduce the phase transition temperature of the Fe2Mo3O12 by substitutional co-incorporation of Zr4+ and Mg2+ in it. It is found that the monoclinic-to-orthorhombic phase transition temperature can be lowered effectively by the co-incorporation. The orthorhombic phase of Fe0.4(ZrMg)0.8Mo3O12 may be obtained at RT and it may keep the orthorhombic structure as low as 103 K. Meanwhile, the co-incorporation of Zr4+ and Mg2+ may tailor the coefficient of thermal expansion (CTE) of the Fe2Mo3O12 and the near-zero CTEs are obtained for the compound around x = 1.7 (Fe0.3(ZrMg)0.85Mo3O12). This work paves the way toward developing low-cost and near-zero thermal expansion materials over wide temperature ranges.

The present study investigated whether a recloning procedure would affect the reproductive performance or the germline transmission capacity of recloned transgenic pigs. This study has also laid the foundation for the development of elite transgenic swine breeds in the future. Recloned transgenic pigs were developed from ear tissue fibroblasts of primary transgenic cloned pigs using a recloning procedure, and their reproductive performance and exogenous gene transmission were analyzed. Two transgenic cell lines with different genetic backgrounds (derived from a female miniature pig and a male Landrace pig) with stable expression of green fluorescent protein (GFP) were established successfully. Furthermore, recloned transgenic embryos were developed to full term successfully. One female Chinese experimental miniature piglet (CEMP) (GFP+) and three male Landrace piglets (GFP+) were delivered naturally. Furthermore, the index values for the reproductive characteristics of the recloned transgenic pigs, such as puberty, gestation period, sperm volume and sperm concentration, were not significantly different from those of conventionally bred pigs. In addition, 53% of the F1 offspring of the recloned transgenic pigs were GFP positive. These results demonstrate that ear tissue fibroblasts from primary transgenic cloned pigs efficiently support the full-term development of recloned transgenic embryos. Furthermore, recloned transgenic pigs maintain normal reproductive performance and stable germline (genetic) transmission capacities.