Subclinical hypothyroidism (SCH) has been shown to be associated with microbiota. However, the association between SCH and oral microbiota has not yet been elucidated. The results of our previous ...clinical studies showed that Prevotella intermedia was abundant in the oral microbiota of SCH patients. This study aimed to investigate the relationship between SCH and oral microbiota, verify the pathogenicity of P. intermedia in SCH, and preliminarily explore the possible mechanism. The SCH mouse model with oral application of P. intermedia was established, and the variance in the mouse oral microbiota and changes in thyroid function and metabolism were detected in mice. Student’s t test and analysis of variance were used for statistical analysis. Oral application of P. intermedia changed the composition of the oral microbiota of SCH mice, which enhanced the damage to the thyroid and decreased the expression of functional genes of the thyroid. Moreover, P. intermedia decreased oxygen consumption and aggravated glucose and lipid metabolism disorders in SCH mice. Glucose tolerance and insulin tolerance decreased, and the triglyceride content of the liver and inflammatory infiltration in adipose tissue increased in SCH mice after P. intermedia stimulation. Mechanistically, P. intermedia increased the proportion of CD4+ T cells in cervical lymph nodes and thyroids in SCH mice. Th1 cells were suggested to play an important role in the pathogenesis of SCH involving P. intermedia. In conclusion, P. intermedia aggravated SCH manifestations, including thyroid dysfunction and glucose and lipid metabolism disorders, by causing immune imbalance in mice. This study sheds new light on the pathogenesis of SCH from the perspective of oral microbiota.
Dysbiotic oral microbiota has been associated with multiple sclerosis. However, the role and mechanism of oral microbiota in the development of multiple sclerosis are still elusive. Here, we ...demonstrated that ligature-induced periodontitis (LIP) aggravated experimental autoimmune encephalomyelitis (EAE) in mice, and this was likely dependent on the expansion of T helper 17 (Th17) cells. LIP increased the splenic richness of Enterobacter sp., which was able to induce the expansion of splenic Th17 cells and aggravate EAE in mice. LIP also led to enrichment of Erysipelotrichaceae sp. in the gut and increased Th17 cells in the large intestinal lamina propria of EAE mice. Fecal microbiota transplantation from EAE mice with LIP also promoted EAE symptoms. In conclusion, periodontitis exacerbates EAE, likely through ectopic colonization of oral pathobionts and expansion of Th17 cells.
High-energy photons from the Crab Nebula
The Crab Nebula contains a pulsar that excites the surrounding gas to emit high-energy radiation. The combination of the pulsar's youth and nearby location ...makes the nebula the brightest gamma-ray source in the sky. The LHAASO Collaboration report observations of this source at energies of tera– to peta–electron volts, extending the spectrum of this prototypical object. They combine these data with observations at lower energies to model the physics of the emission process. The multiwave-length data can be explained by a combination of synchrotron radiation and inverse Compton scattering.
Science
, abg5137, this issue p.
425
Detection of the Crab Nebula at peta–electron volt energies constrains the gamma-ray emission mechanism.
The Crab Nebula is a bright source of gamma rays powered by the Crab Pulsar’s rotational energy through the formation and termination of a relativistic electron-positron wind. We report the detection of gamma rays from this source with energies from 5 × 10
−4
to 1.1 peta–electron volts with a spectrum showing gradual steepening over three energy decades. The ultrahigh-energy photons imply the presence of a peta–electron volt electron accelerator (a pevatron) in the nebula, with an acceleration rate exceeding 15% of the theoretical limit. We constrain the pevatron’s size between 0.025 and 0.1 parsecs and the magnetic field to ≈110 microgauss. The production rate of peta–electron volt electrons, 2.5 × 10
36
ergs per second, constitutes 0.5% of the pulsar spin-down luminosity, although we cannot exclude a contribution of peta–electron volt protons to the production of the highest-energy gamma rays.
Nuclear receptor corepressor 1 (Ncor1) has been reported to regulate different transcription factors in different biological processes, including metabolism, inflammation, and circadian rhythms. ...However, the role of Ncor1 in periodontitis has not been elucidated. The aims of the present study were to investigate the role of Ncor1 in experimental periodontitis and to explore the underlying mechanisms through an experimental periodontitis model in myeloid cell–specific Ncor1-deficient mice. Myeloid cell–specific Ncor1 knockout (MNKO) mice were generated, and experimental periodontitis induced by ligation using 5-0 silk sutures was established. Ncor1 flox/flox mice were used as littermate controls (LC). Histological staining and micro–computed tomography scanning were used to evaluate osteoclastogenesis and alveolar bone resorption. Flow cytometry was conducted to observe the effect of Ncor1 on myeloid cells. RNA sequencing was used to explore the differentially targeted genes in osteoclastogenesis in the absence of Ncor1. Coimmunoprecipitation (Co-IP), chromatin immunoprecipitation (ChIP) experiments, and dual luciferase assays were performed to explore the relationship between NCoR1 and the targeted gene. Alveolar bone resorption in the MNKO mice was significantly greater than that in the LC mice after periodontitis induction and osteoclastogenesis in vitro. The percentage of CD11b+ cells, particularly CD11b+ Ly6G+ neutrophils, was substantially higher in gingival tissues in the MNKO mice than in the LC mice. Results of RNA sequencing demonstrated that CCAAT enhancer binding protein α (Cebpα) was one of the most differentially expressed genes between the MNKO and LC groups. Mechanistically, Co-IP assays, ChIP experiments, and dual luciferase assays revealed that NCOR1 interacted with peroxisome proliferator-activated receptor gamma (PPARγ) and cooperated with HDAC3 to control the transcription of Cebpα. In conclusion, Ncor1 deficiency promoted osteoclast and neutrophil formation in mice with experimental periodontitis. It regulated the transcription of Cebpα via PPARγ to promote osteoclast differentiation.
In this study, a technique that allows electron backscatter diffraction (EBSD) observation in the same point of interest under uniaxial tensile testing, i.e., a quasi in situ EBSD analysis technique, ...was developed and performed to investigate the interaction between slip and {101¯2} tensile twinning in a Zr alloy. Both the slip-independent and slip-assisted {101¯2} twins were investigated. The former twin is formed when the global stress surpassed the required critical stress, and the latter one is formed due to the local stress concentration near the grain boundary accumulated in the soft-oriented adjacent grain, although the global stress remains insufficient to activate the twinning. The formation of a slip-independent or slip-assisted {101¯2} twin seems to be closely linked to the crystal orientation relative to the loading direction. It is due to the bimodal basal texture exhibited in the present alloy that the slip-assisted twins can be observed. Furthermore, compared to slip-independent twins, the slip-assisted twinning is more likely to form at a higher strain, because substantial strain accumulation is essential to trigger its activation.
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•The interaction between slip and {10–12} twinning in a Zr alloy was investigated.•Both the slip-independent and slip-assisted {10–12} twins were investigated.•Slip-assisted twin formed due to the local stress concentration in adjacent grain.•Bimodal basal texture accounts as the reason of the slip-assisted twin formation.•A higher strain is required for slip-assisted twin relative to slip-independent one.
•LSP can greatly delay crack formation.•The micro-crack growing processes and its fracture are showed clearly.•Surface topographies and crack initiation locations are displayed.
A series of ...contrasting experiments were carried out to examine the effects of laser shock processing (LSP) on fatigue properties of slot in 7075-T6 aluminum alloy plate. Both side surfaces of slot were subjected to LSP. The surface topographies were observed and the residual stresses were tested. The treated and the un-treated specimens were pulled by the fatigue cyclic loading respectively. The fatigue crack propagating processes were recorded, and the fatigue fracture microscopic morphologies were analyzed by scanning electron microscope (SEM). Experimental results and analyses show that LSP induces micro-dent on surface and squeezes the compressive residual stresses into surface layer of specimen. It can remarkably delay the micro-crack formation, and transfer the location of fatigue crack initiation from top surface to sub-surface. The spacing of fatigue striations on the treated specimen fatigue fracture obviously decreases. Therefore, the fatigue life of specimen after LSP treatment significantly increases.
Although Rhodiola sacra aqueous extract (RSAE) has been used in many studies as an antioxidant, its effects on semen characteristics and its antioxidant properties during cryopreservation of boar ...sperm have never been evaluated. Semen was collected from five Duroc boars (2–4-year-old) twice weekly and frozen–thawed in extender with RSEA. Motion characteristics were assessed with a computer-aided semen analysis (CASA) system, whereas other sperm quality end points were assessed by routine methods. The effective concentration of RSEA in extender ranged from 4 to 8mg/L and the effect of RSEA on sperm quality was better in glycerol-free extender than extender containing glycerol (P<0.05). In frozen–thawed boar semen, there was a direct correlation (P<0.05) between RSEA concentration and glutathione (GSH) concentrations, mitochondrial activity, and hypoosmotic swelling test (HOST), and an inverse correlation (r=−0.982, P<0.05) between RSEA concentration and malondialdehyde (all end points were significantly higher at 6mg/L than in the control group). In summary: (i) the effective concentration of RSEA in extender ranged from 4 to 8mg/L; (ii) the effect of RSEA on sperm quality was better in extender without glycerol; and (iii) there was a significant correlation between RSEA concentrations and concentrations of GSH and MAD in frozen–thawed boar semen (antioxidant effects of RSEA were concentration-dependent). Further studies are needed to define the active ingredient in RSEA that protects boar sperm against ROS.
A non-linear unknown input observer (UIO) is designed for systems with non-linearities having lower bonds on their slopes. The observer is constructed such that the non-linearity in the observer ...error system satisfies a sector property. Based on this property rather than the Lipschitz property, an algorithm not limited by Lipschitz constant is proposed. Further, all the parameters in the proposed non-linear UIO can be calculated by solving a linear matrix inequality. The UIO is also extended to an adaptive one for a class of uncertain non-linear systems in which the arguments of non-linear terms are perturbed by unknown parameters. Finally, simulations of electric driving system are used to illustrate the effectiveness of the UIOs. PUBLICATION ABSTRACT
Abstract
We report the discovery of an ultrahigh-energy (UHE) gamma-ray source, LHAASO J2108+5157, by analyzing the LHAASO-KM2A data of 308.33 live days. A significant excess of gamma ray–induced ...showers is observed in both energy bands of 25−100 and >100 TeV with 9.5
σ
and 8.5
σ
, respectively. This source is not significantly favored as an extended source with an angular extension smaller than the point-spread function of KM2A. The measured energy spectrum from 20 to 200 TeV can be approximately described by a power-law function with an index of −2.83 ± 0.18
stat
. A harder spectrum is demanded at lower energies considering the flux upper limit set by Fermi-LAT observations. The position of the gamma-ray emission is correlated with a giant molecular cloud, which favors a hadronic origin. No obvious counterparts have been found, and deeper multiwavelength observations will help to cast new light on this intriguing UHE source.