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Compared with antiferroelectric (AFE) orthorhombic R phases, AFE orthorhombic P phases in NaNbO3 (NN) ceramics have been rarely investigated, particularly in the field of energy-storage capacitors. The main bottleneck is closely related to the contradiction between difficultly-achieved stable relaxor AFE P phase and easily induced P-R phase transition during modifying chemical compositions. Herein, we report a novel lead-free AFE ceramic of (1-x)NN-x(Bi0.5K0.5)ZrO3 ((1-x)NN-xBKZ) with a pure AFE P phase structure, which exhibits excellent energy-storage characteristics, such as an ultrahigh recoverable energy density (Wrec) ∼4.4 J/cm3 at x = 0.11, a large powder density PD ∼104 MW/cm3 and a fast discharge rate t0.9 ∼45 ns. The analysis of polarization-field response, Raman spectrum and transmission electron microscopy demonstrates that the giant amplification of Wrec by ≥177% should be mainly ascribed to the simultaneously and effectively enhanced AFE P-phase stability and its relaxor characteristics, resulting in a diffused reversible electric field-induced AFE P-ferroelectric phase transition with concurrently increased driving electric fields. Different from most (1-x)NN-xABO3 systems, it was found that the reduced polarizability of B-site cations dominates the enhanced AFE P-phase stability in (1-x)NN-xBKZ ceramics, but the almost unchanged tolerance factor tends to cause the AFE R phase to be induced at a relatively high x value.

Objective For treatment of infected femoral artery pseudoaneurysms (IFAPs) with the covered stent, debridement technique is important but frequently ignored. Our study aims to review our experience and outcomes of patients undergoing covered stents placement and debridement with vacuum sealing drainage (VSD). Methods This study retrospectively analyzed 41 intravenous drug addicts with IFAP who received covered stent implantation and debridement with VSD from January 2015 to December 2020. The diagnosis was based on the previous history of local injection and the presence of pulsatile mass at the injection site. All cases were confirmed by CT angiography (CTA), ultrasound, or digital subtraction angiography (DSA). Technical success, time of wound care, and clinical outcomes were evaluated. Results Technical success was achieved in all patients. The interval from diagnosis to treatment was 26 ± 11 hours. The time of continuous drainage with VSD was 18.79 ± 6.56 days. 38 patients (92.68%) with fresh granulation tissue were sutured and discharged from the hospital. Stents in 31(91.18%) of 34 cases were patent during follow-ups. Three patients had stent occlusion caused by thrombosis, and two of them were complicated with stent infection. The two infectious stents were removed and the femoral arteries were ligated. One of them received open-surgical reconstruction with the great saphenous because of claudication. Two patients were admitted to the hospital for rebleeding caused by drug abuse relapse. Conclusion Covered stents placement is convenient and rapid to control massive hemorrhage in IFAPs of intravenous drug abuse. Early debridement of infected tissue with continued VSD may shorten the time of wound care and make the incidence of stent infection relatively low. Meanwhile, the patency in a short time follow-up is acceptable. These results indicates that covered stents implantation with VSD may be a safe, effective, and feasible measure for the treatment of IFAPs.

A ternary solid-solution piezoelectric ceramic of rare-earth oxides modified 0.03 Pb(Mn1/3Sb2/3)O3-0.97 Pb(Zr0.505Ti0.495)O3 + x wt.% CuO + y wt.% Bi2O3 (PMS-PZT + x wt.% CuO + y wt. % Bi2O3) (x, y = 0–0.2) was successfully prepared via a transient-liquid-phase sintering. Both Cu2+ and Bi3+ were believed to replace the A-site Pb ions and to evidently induce the lattice shrinkage and the distortion decrease. However, the addition of only a small amount of CuO was found to effectively reduce the sintering temperature, sustain good piezoelectric properties and predominant transgranular fracture modes, but obviously increase the average grain size and high-field dielectric loss. Further experimental results indicate that the grain growth of the ceramics was inhibited effectively and the high-field dielectric loss was reduced through CuO and Bi2O3 co-doping. The 0.05 wt% CuO and 0.15 wt% Bi2O3 co-doped PMS-PZT ceramics sintered at 1050 °C exhibit excellent dielectric and piezoelectric properties of d33 = 410 pC/N, kp = 0.62, Qm = 1478, er = 1550, tan δ = 0.8% (400 V/mm) and Tc = 330 °C. The experimental results can provide a solid fundament for multilayer piezoelectric actuating devices.

Endovascular treatment with percutaneous transluminal angioplasty and stenting has quickly gained popularity for treatment of deep venous obstructive disease. Early thrombosis after stenting in iliofemoral veins is uncommon. The treatment and analysis of the underlying factors leading to the rethrombosis of stents placed in the previous 14 days are reported in this study.Patients diagnosed with early in-stent thrombosis after iliofemoral stenting were reviewed in this retrospective analysis. Patients with acute occlusion were routinely treated by catheter-directed thrombolysis (CDT), and the underlying causes of early occlusion were identified during the procedure. After successful CDT procedures, patients received additional interventions (percutaneous transluminal angioplasty with or without stenting) if indicated.A total of 527 patients underwent stenting in the iliofemoral veins, and 32 patients (20 men [63%]) with acute thrombosis in iliofemoral venous stents placed in the previous 14 days were treated in our center from January 2015 to December 2018. The mean time from the onset of symptoms to the intervention was 6 days. Successful thrombolysis was achieved in 31 of the 32 patients, and additional stents were implanted in 16 patients. Patency was achieved in all cases. The underlying factors of early stent thrombosis were technical failure of the initial procedure, such as suboptimal positioning, failure owing to stent characteristics (stent kinking, compression, and angulation), in-stent residual thrombus, and inadequate anticoagulation. In all cases, recanalization was achieved through successful thrombolysis with or without restenting.Treatment with CDT and stenting of early in-stent thrombosis is effective and feasible. Recanalization of stented segment(s) can be achieved in most cases of recent thrombosis (14 days). Early stent-related occlusion is mainly caused by stent-related problems and technical inadequacies.

Evaluating the dispersion of SiC nanoparticles is significant for the development of ZrB2–SiC nanocomposite ceramics. This paper reports the 3D distribution characterization of the nanosized SiC additives in ZrB2–SiC ceramics with synchrotron X-ray nanoscale computed tomography (nano-CT) and Morisita indexes. Different from the investigation with electron microscopy, the presented work implements nondestructively 3D visualization and quantitative characterization of the SiC nanoparticles distribution in ZrB2–SiC ceramics. Firstly, a ZrB2–SiC ceramic sample with a size less than 60 μm was prepared. Then, a nano-CT experiment was designed and implemented for this sample at the 4W1A beamline of Beijing Synchrotron Radiation Facility (BSRF). Next, SiC nanoparticles were extracted by applying image segmentation to the generated 3D nano-CT images of this sample and visualized by volume rendering. Finally, Morisita index was extended from 2D to 3D and applied to the corresponding nano-CT images for the quantitative characterization of SiC nanoparticle 3D distribution. The results from the Morisita index are in good agreement with the visual observation. They reveal that SiC agglomerates exist in the ZrB2 matrix and vary over the regions of interest in the investigated sample.

Long-term straw return is an important carbon source for improving soil organic carbon (SOC) stocks in croplands, and straw removal through burning is also a common practice in open fields in South China. However, the specific effects of long-term rice straw management on SOC fractions, the related enzyme activities and their relationships, and whether these effects differ between crop growing seasons remain unknown. Three treatments with equal nitrogen, phosphorus, and potassium nutrient inputs, including straw/ash and chemical nutrients, were established to compare the effects of straw removal (CK), straw return (SR), and straw burned return (SBR). Compared to CK, long-term SR tended to improve the yield of early season rice (P=0.057), and significantly increased total organic carbon (TOC) and microbial biomass carbon (MBC) in double-cropped rice paddies. While SBR had no effect on TOC, it decreased light fraction organic carbon (LFOC) in early rice and easily oxidizable organic carbon (EOC) in late rice, significantly increased dissolved organic carbon (DOC), and significantly decreased soil pH. These results showed that MBC was the most sensitive indicator for assessing changes of SOC in the double-cropped rice system due to long-term straw return. In addition, the different effects on SOC fraction sizes between SR and SBR were attributed to the divergent trends in most of the soil enzyme activities in the early and late rice that mainly altered DOC, while DOC was positively affected by β-xylosidase in both early and late rice. We concluded that straw return was superior to straw burned return for improving SOC fractions, but the negative effects on soil enzyme activities in late rice require further research.

Evidence suggests that the Parkinson’s disease (PD) pathogenesis is strongly associated with bidirectional pathways in the microbiota-gut-brain axis (MGBA), and psychobiotics may inhibit PD progression. We previously reported that the novel psychobiotic strain, Lactobacillus plantarum PS128 (PS128), ameliorated abnormal behaviors and modulated neurotransmissions in dopaminergic pathways in rodent models. Here, we report that orally administering PS128 for 4 weeks significantly alleviated the motor deficits, elevation in corticosterone, nigrostriatal dopaminergic neuronal death, and striatal dopamine reduction in 1-methyl-4-phenyl-1,2,3,6-tetrathydropyridine (MPTP)-induced PD mouse models. PS128 ingestion suppressed glial cell hyperactivation and increased norepinephrine and neurotrophic factors in the striatum of the PD-model mice. PS128 administration also attenuated MPTP-induced oxidative stress and neuroinflammation in the nigrostriatal pathway. Fecal analysis showed that PS128 modulated the gut microbiota. L. plantarum abundance was significantly increased along with methionine biosynthesis-related microbial modules. PS128 also suppressed the increased family Enterobacteriaceae and lipopolysaccharide and peptidoglycan biosynthesis-related microbial modules caused by MPTP. In conclude, PS128 ingestion alleviated MPTP-induced motor deficits and neurotoxicity. PS128 supplementation inhibited neurodegenerative processes in PD-model mice and may help prevent PD.

The multi-phase coexistence is a technologically important concept in high-performance piezoelectric ceramics owing to the ability of achieving extremely increased electromechanical properties. However, in fact it cannot always produce desirable thermal stability of small-field piezoelectric properties relevant to the device application. In this work, a typical lead-free piezoelectric composition of (Na0.52K0.4)(Nb0.84Sb0.08)O3–0.055LiTaO3–0.025BaZrO3 coexisted with rhombohedral (R) and tetragonal (T) phases at room temperature was investigated as a case study by means of ex/in-situ synchrotron x-ray diffraction, Rietveld structure refinement and measurements of temperature-dependent electrical properties. The refined crystal structure proves to be a three-phase coexistence of R, orthorhombic (O) and T at virgin state, and evolves into the R+monoclinic (MC)+T phase coexistence at poled state owing to an electric field induced irreversible O-MC phase transition. Particularly, the field induced MC phase can stably exist and maintain its concentration as long as the annealing temperature is below the Curie temperature. An interesting finding is that the poled sample still retains the polymorphism of phase transition like its virgin state featuring the temperature driven R-O(MC)-T phase transition, leading to seriously degraded piezoelectric coefficients after thermal cycles due to domain de-texturing of not only MC phase, but also R and T phases during repeated phase transition. The present study would benefit to understanding of the nature of polymorphic phase boundary and the structure origin of temperature-dependent piezoelectric properties in R-T coexisted (Na,K)NbO3-based lead-free solid-solution ceramics.