1,568 research outputs found
Interaction effects of pseudospin-based magnetic monopoles and kinks in a doped dipolar superlattice gas
Magnetic monopoles and kinks are topological excitations extensively
investigated in quantum spin systems, but usually they are studied in different
setups. We explore the conditions for the coexistence and the interaction
effects of these quasiparticles in the pseudospin chain of the atomic dipolar
superlattice gas. In this chain, the magnetic kink is the intrinsic
quasiparticle, and the particle/hole defect takes over the role of the
north/south magnetic monopole, exerting monopolar magnetic fields to
neighboring spins. A confinement effect between the monopole and kink is
revealed, which renormalizes the dispersion of the kink. The corresponding
dynamical deconfinement process is observed and arises due to the kink-antikink
annihilation. The rich interaction effects of the two quasiparticles could
stimulate corresponding investigations in bulk spin systems
Magnetic monopole induced polarons in atomic superlattices
Magnetic monopoles have been realized as emergent quasiparticles in both
condensed matter and ultracold atomic platforms, with growing interests in the
coupling effects between the monopole and different magnetic quasiparticles. In
this work, interaction effects between monopoles and magnons are investigated
for an atomic pseudospin chain. We reveal that the monopole can excite a
virtual magnon cloud in the paramagnetic chain, thereby giving rise to a new
type of polaron, the monopole-cored polaron (McP). The McP is composed of the
monopole as the impurity core and the virtual magnon excitation as the dressing
cloud. The magnon dressing facilitates the Dirac string excitation and impacts
the monopole hopping. This induces an anti-trapping effect of the McP, which
refers to the fact that the dressing enhances the mobility of the McP, in
contrast to the self-trapping of the common polarons. Moreover, heterogeneous
bipolarons are shown to exist under the simultaneous doping of a north and a
south monopole. The heterogeneous bipolaron possesses an inner degree of
freedom composed of two identical impurities. Our investigation sheds light on
the understanding of how the coupling between the impurity core and the
dressing cloud can engineer the property of the polaro
Manifold formation and crossings of ultracold lattice spinor atoms in the intermediate interaction regime
Ultracold spinor atoms in the weak and strong interaction regime have
received extensive investigations, while the behavior in the intermediate
regime is less understood. We numerically investigate ultracold spinor atomic
ensembles of finite size in the intermediate interaction regime, and reveal the
evolution of the eigenstates from the strong to the intermediate regime. In the
strong interaction regime, it has been well known that the low-lying
eigenenergy spectrum presents the well-gaped multi-manifold structure, and the
energy gaps protect the categorization of the eigenstates. In the intermediate
interaction regime, it is found that the categorization of the eigenstates is
preserved, and the eigenenergy spectrum become quasi-continuum, with different
manifolds becoming overlapped. The overlapping induces both direct and avoided
crossings between close-lying manifolds, which is determined by the combined
symmetries of the eigenstates involved in the crossing. A modified t-J model is
derived to describe the low-lying eigenstates in the intermediate regime, which
can capture the formation and crossings of the manifolds. State preparation
through the avoided crossings is also investigated.Comment: 8 pages,6 figure
Prediction on the relative permittivity of energy storage composite dielectrics using convolutional neural networks: A fast and accurate alternative to finite-element method
The relative permittivity is one of the essential parameters determines the physical polarization behaviors of the nanocomposite dielectrics in many applications, particularly for capacitive energy storage. Predicting the relative permittivity of particle/polymer nanocomposites from the microstructure is of great significance. However, the classical effective medium theory and physics-based numerical calculation represented by finite element method are time-consuming and cumbersome for complex structures and nonlinear problem. The work explores a novel architecture combining the convolutional neural network (ConvNet) and finite element method (FEM) to predict the relative permittivity of nanocomposite dielectrics with incorporated barium titanite (BT) particles in polyvinylidene fluoride (PVDF) matrix. The ConvNet was trained and evaluated on big datasets with 14266 training data and 3514 testing data generated form a programmatic algorithm. Through numerical experiments, we demonstrate that the trained network can efficiently provide an accurate agreement between the ConvNet model and FEM by virtue of the significant evaluation metrics R2, which reaches as high as 0.9783 and 0.9375 on training and testing data, respectively. The strong universality of the presented method allows for an extension to fast and accurately predict other properties of the nanocomposite dielectrics
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Molecular identification of Trichinella spiralis nudix hydrolase and its induced protective immunity against trichinellosis in BALB/c mice
Background: Nudix hydrolases (Nd) is a widespread superfamily, which is found in all classes of organism, hydrolyse a wide range of organic pyrophosphates and has a ‘housecleaning’ function. The previous study showed that Trichinella spiralis Nd (TsNd) bound to intestinal epithelial cells (IECs), and the vaccination of mice with T7 phage-displayed TsNd polypeptides produced protective immunity. The aim of this study was to clone, express and identify the full-length TsNd and to investigate its immune protection against T. spiralis infection. Methods: The full-length cDNA sequence of TsNd gene encoding a 46 kDa protein from T. spiralis intestinal infective larvae (IIL) was cloned and identified. The antigenicity of rTsNd was analyzed by Western blot. Transcription and expression of TsNd at T. spiralis different stages were observed by RT-PCR and IFT. The levels of the specific total IgG, IgG1 and IgG2a antibodies to rTsNd were determined by ELISA. The immune protection of rTsNd against T. spiralis infection was investigated. Results: Sequence and phylogenetic analysis revealed that TsNd had a nudix motif located at 226-244aa, which had high homology and the closest evolutionary status with T. pseudospiralis. The rTsNd was obtained after expression and purification. Western blot analysis showed that anti-rTsNd serum recognized the native TsNd protein in crude antigens of muscle larvae (ML), IIL, adult worms (AW) and newborn larvae (NBL), and ES antigens of ML. Transcription and expression of TsNd gene was observed in all developmental stages of T. spiralis (ML, IIL, AW and NBL), with high level expression in IIL. An immunolocalization analysis identified TsNd in the cuticle, stichocytes and reproductive organs of the parasite. Following immunization, anti-rTsNd IgG levels were increased, and the levels of IgG1 were more significantly higher than that of IgG2a. After a challenge infection with T. spiralis, mice immunized with the rTsNd displayed a 57.7% reduction in adult worms and a 56.9% reduction in muscle larval burden. Conclusions: TsNd induced a partial protective immunity in mice and could be considered as a novel candidate vaccine antigen against trichinellosis
Protective immunity against Trichinella spiralis infection induced by TsNd vaccine in mice
BACKGROUND: We have previously reported that Trichinella spiralis Nudix hydrolase (TsNd) bound to intestinal epithelial cells (IECs), and vaccination of mice with recombinant TsNd protein (rTsNd) produced a partial protective immunity. The aim of this study was to investigate the immune protection induced by TsNd DNA vaccine. METHODS: The full-length cDNA sequence of TsNd gene was cloned into pcDNA3.1 and used to immunize BALB/c mice by intramuscular injection. Transcription and expression of TsNd were detected by RT-PCR and IFT. The levels of specific IgA, IgG, IgG1 and IgG2a, and cytokines were assayed by ELISA at weeks 0, 6 and 8 post-immunization. The immune protection of TsNd DNA vaccine against challenge infection was investigated. RESULTS: Immunization of mice with TsNd DNA elicited a systemic Th1/Th2 immune response and a local mucosal IgA response. The in vitro transcription and expression of TsNd gene was observed at all developmental stages of T. spiralis (ML, IIL, AW and NBL). Anti-rTsNd IgG levels were increased after immunization and levels of IgG1 were obviously higher than that of IgG2a. Intestinal specific IgA levels of immunized mice were significantly higher than those of vector and PBS control mice. Cytokine profiling also showed a significant increase in Th1 (IFN-γ, IL-2) and Th2 (IL-4, 10) responses in splenocytes of immunized mice on stimulation with rTsNd. Vaccination of mice with pcDNA3.1-TsNd displayed a 40.44% reduction in adult worms and a 53.9% reduction in larval burden. CONCLUSIONS: TsNd DNA induced a mixed Th1/Th2 immune response and partial protection against T. spiralis infection in mice
AI safety of film capacitors.
With a large number of film capacitors being deployed in critical locations in electrical and electronic systems, artificial intelligence (AI) technology is also expected to address the problems encountered in this process. According to our findings, AI applications can cover the entire lifecycle of film capacitors. However, the AI safety hazards in these applications have not received the attention they deserve. To meet this, the authors argue, with specific examples, risks that flawed, erratic, and unethical AI can introduce in the design, operation, and evaluation of film capacitors. Human-AI common impact and more multi-dimensional evaluation for AI are proposed to better cope with unknown, ambiguity, and known risks brought from AI in film capacitors now and in the future
Autologous Skin Fibroblast-Based PLGA Nanoparticles for Treating Multiorgan Fibrosis
Fibrotic diseases remain a substantial health burden with few therapeutic approaches. A hallmark of fibrosis is the aberrant activation and accumulation of myofibroblasts, which is caused by excessive profibrotic cytokines. Conventional anticytokine therapies fail to undergo clinical trials, as simply blocking a single or several antifibrotic cytokines cannot abrogate the profibrotic microenvironment. Here, biomimetic nanoparticles based on autologous skin fibroblasts are customized as decoys to neutralize multiple fibroblast-targeted cytokines. By fusing the skin fibroblast membrane onto poly(lactic-co-glycolic) acid cores, these nanoparticles, termed fibroblast membrane-camouflaged nanoparticles (FNPs), are shown to effectively scavenge various profibrotic cytokines, including transforming growth factor-beta, interleukin (IL)-11, IL-13, and IL-17, thereby modulating the profibrotic microenvironment. FNPs are sequentially prepared into multiple formulations for different administration routines. As a proof-of-concept, in three independent animal models with various organ fibrosis (lung fibrosis, liver fibrosis, and heart fibrosis), FNPs effectively reduce the accumulation of myofibroblasts, and the formation of fibrotic tissue, concomitantly restoring organ function and indicating that FNPs are a potential broad-spectrum therapy for fibrosis management.Peer reviewe
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