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Abstract Objective To analyze the characteristics of “severe” dynamic sagittal imbalance (DSI) in patients with adult spinal deformity (ASD) and establish criteria for them. Methods We retrospectively analyzed 102 patients with ASD presenting four cardinal signs of lumbar degenerative kyphosis. All patients underwent deformity corrective surgery and were divided into three groups according to the diagnostic criteria based on the Oswestry disability index and dynamic features (△Timewalk: time until C7 sagittal vertical axis [C7SVA] reaches ≥ 20 cm after the start of walking) of sagittal imbalance. The paravertebral back muscles were analyzed and compared using T2-weighted axial imaging. We performed a statistically time-dependent spinopelvic sagittal parameter analysis of full standing lateral lumbar radiographs. Lumbar flexibility was analyzed using dynamic lateral lumbar radiography. Results The patients were classified into the mild (△Timewalk ≥ 180 s, 35 patients), moderate (180 s > △Timewalk ≥ 30 s, 38 patients), and severe (△Timewalk 20 cm within 30 s of walking or standing, a rigid lumbar curve 75.3°. Level of evidence 3.

Highlights Critical issues including mechanical stability, water and oxygen resistance, transparent electrodes for flexible perovskite solar cells are discussed. Roll-to-Roll technology presents a promising avenue for fabrication of flexible perovskite solar cells fabricated for large-scale commercial application. Balancing the transmittance and conductivity of transparent electrodes has become a significant issue in developing efficient flexible perovskite solar cells.

Perovskite photovoltaic has been attracting intense attention as an emerging technology due to its figure of merits including high power conversion efficiency, low-cost fabrication, and others. A successful commercialization of this type of technology has been significantly retarded by issues of elemental toxicity and device stability which are related to the key component of lead (Pb) in most efficient halide perovskites. Here, we first elucidated the origin of the superior optoelectronic properties of lead halide perovskites and their impact on photovoltaic device performance. We then discussed the promising approaches to solve the toxicity issue of lead hybrid perovskites. We further outlooked the effective solutions for lead hybrid perovskites for solar cell application. This review may provide a guidance for researchers interested in facilitating perovskite solar cells from exploitation to application.

Photodetector is an essential component in many optoelectronic devices nowadays that converts the incoming optical signal into an electrical signal. The need for multi-spectral photoelectric detection in the same scene promotes the application of wide spectrum detection. Halide hybrid perovskites can be excellent candidates for wide-spectrum photodetectors which cover a spectral range of UV–visible–infrared. However, the intrinsic defects of perovskite material and the defects among various functional layers might increase the dark current and seriously reduce the photodetector device optoelectronic performance. Therefore, reducing the dark current and improving the spectra-detection performance of ultra-wideband radiation perovskite photodetectors are the main targets for investigation of high-efficient perovskite photodetectors. In this mini-review, the parameters that determine the dark current of perovskite photodetectors and their effects on the device performance are discussed for the first time. Then this work evaluated the promising approaches to solve the defect-dependent recombination in perovskite photodetectors. We further outlooked the effective approaches for perovskite photodetectors for wide-spectrum application.

Abstract Background We hypothesized that posterior osteotomy prior to ACR (Anterior column realignment) through P-A-P surgical sequence would permit a greater correction for deformity corrective surgery than the traditional A-P sequence without posterior osteotomy. This study aimed to determine the impact of the P-A-P sequence on the restoration of lumbar lordosis (LL) compared to the A-P sequence in deformity corrective surgery for adult spinal deformity (ASD) patients and to identify the characteristics of patients who require this sequence. Methods Between 2017 and 2019, 260 ASD patients who had undergone combined corrective surgery were reviewed retrospectively. This study included 178 patients who underwent posterior osteotomy before the ACR (P-A group) and 82 patients who underwent the A-P sequence (A-P group). Sagittal spinopelvic parameters were determined from pre- and postoperative whole-spine radiographs and compared between the groups. To find better indications for the P-A-P sequence, we conducted additional analysis on postoperative outcomes of patients in the A-P group. Results The P-A group showed a significantly higher change in LL (53.7° vs. 44.3°, p

The development of environmentally friendly ceramics for electrostatic energy storage has drawn growing interest due to the wide application in high power and/or pulsed power electronic systems. However, it is difficult to simultaneously achieve ultrahigh recoverable energy storage density (Wrec > 8 J/cm3) and high efficiency (η > 80 %), which restricts their application in the miniaturized, light weight and easy integrated electronic devices. Herein, the novel NaNbO3-(Bi0.8Sr0.2)(Fe0.9Nb0.1)O3 relaxor antiferroelectric ceramics, which integrates the merits of antiferroelectrics and relaxors, are demonstrated to exhibit stabilized antiferroelectric phase and enhanced dielectric relaxor behavior. Of particular importance is that the 0.88NN-0.12BSFN ceramic achieves giant electric breakdown strength Eb = 98.3 kV/mm, ultrahigh Wrec = 16.5 J/cm3 and high η = 83.3 %, as well as excellent frequency, cycling and thermal reliability simultaneously. The comprehensive energy storage performance of NN-BSFN not only outperforms state-of-the-art dielectric ceramics by comparison, but also displays outstanding potential for next-generation energy storage capacitors.

Dielectric capacitors reveal great potential in the application of high power and/or pulsed power electronic devices owing to their ultrafast charge–discharge rate and ultrahigh power density. Among various dielectric capacitors, the environment-friendly lead-free dielectric ceramics have drawn extensive investigations in recent years. Nevertheless, the relatively small recoverable energy storage density (Wrec) is still an obstacle for their application. Herein, the (0.55−x)BiFeO3–0.45SrTiO3–xBaTiO3 ternary ceramics with 0.1 wt% MnO2 were prepared by the solid-state reaction, and achieved enhanced relaxor behavior as well as breakdown strength Eb. As a result, the x = 0.12 ceramic exhibited superior comprehensive energy storage performance of large Eb (50.4 kV/mm), ultrahigh Wrec (7.3 J/cm³), high efficiency η (86.3%), relatively fast charge–discharge speed (t0.9 = 6.1 μs) and outstanding reliability under different frequency, fatigue, and temperature, indicating that the BiFeO3-based relaxor ferroelectric ceramics are prospective alternatives for electrostatic energy storage. [ABSTRACT FROM AUTHOR]

Abstract The balance among different CD4+ T cell subsets is crucial for repairing the injured spinal cord. Dendritic cell (DC)‐derived small extracellular vesicles (DsEVs) effectively activate T‐cell immunity. Altered peptide ligands (APLs), derived from myelin basic protein (MBP), have been shown to affect CD4+ T cell subsets and reduce neuroinflammation levels. However, the application of APLs is challenging because of their poor stability and associated side effects. Herein, it is demonstrate that DsEVs can act as carriers for APL MBP87‐99A91 (A91‐DsEVs) to induce the activation of 2 helper T (Th2) and regulatory T (Treg) cells for spinal cord injury (SCI) in mice. These stimulated CD4+ T cells can efficiently “home” to the lesion area and establish a beneficial microenvironment through inducing the activation of M2 macrophages/microglia, inhibiting the expression of inflammatory cytokines, and increasing the release of neurotrophic factors. The microenvironment mediated by A91‐DsEVs may enhance axon regrowth, protect neurons, and promote remyelination, which may support the recovery of motor function in the SCI model mice. In conclusion, using A91‐DsEVs as a therapeutic vaccine may help induce neuroprotective immunity in the treatment of SCI.

Background and Aim: As a new feed additive, bile acid (BA) can promote the absorption and transport of lipids and fat-soluble vitamins. In recent years, BAs have been widely used in animal feed to promote fat absorption. Therefore, this study aimed to investigate the effect of bile salt supplementation in the diet of yellow-feathered broilers on messenger RNA (mRNA) expression of sterol regulatory element-binding protein 1 (SREBF1), fatty acid synthase (FAS), acetyl-coenzyme A carboxylase (ACC), and fatty acid transport protein 4 (FATP4). Materials and Methods: Four hundred and twenty commercial male chicks were randomly divided into seven groups (with four replicates per group and 15 chickens per replicate). They were fed diets supplemented with bile salts at 0, 1.5, 2.5, 3.5, 4.5, 5.5 mg/kg, and 2 mg/kg tylosin for 30 days. Changes in SREBF1, fatty acid transporter 4, FAS, and acetyl- CoA carboxylase genes in intestinal mucosa and liver of yellow-feathered broilers were determined using a quantitative fluorescence polymerase chain reaction. Results: mRNA expression of SREBF1, FAS, ACC, and FATP4 in the small intestine decreased in chicks fed diets supplemented with 3.5 and 4.5 mg/kg bile salts (p

Supramolecular polymers based on supramolecular coordination complexes (SCCs) have received extensive attention because of their good stimulus responsiveness, processability and other properties. Herein, we report metallacycle-crosslinked supramolecular polymers via amino–yne click reaction, which were employed as well-performing elastomer materials. The supramolecular polymers cross-linked by the metallacycle not only maintained the aggregation induced emission (AIE) properties of the metallacycle, which were used to detect nitroaromatic explosives, but also had enhanced mechanical strength and toughness and exhibited elastomeric properties. This study provides a feasible strategy for the preparation of metallacycle-based supramolecular polymers with better mechanical properties.

An asymmetrical suspension structure, without vertical column support and without supplying the flexibility of spatial arrangement, is more sensitive to ground movement. The structural responses of an asymmetrical suspension structure subjected to Clough–Penzien spectrum excitation were analytically investigated in this study. First, the governing equation was decoupled into an independent state equation in generalized coordinates through the real mode decomposition method and by creatively combining it with finite element methods to acquire modal coefficients. Through the pseudo excitation method (PEM), the frequent domain solution of the dynamic response was acquired, and its power spectrum density function was then quadratically decomposed to obtain its corresponding 0–2-order spectral moments. A practical case study was performed to verify the high accuracy and computational efficiency of the proposed closed-form solution comparative to the traditional PEM. Finally, an extended analysis of the effect of the suspended span and comparisons to a normal framed structure and symmetrical suspension structures were carried out. The analysis results indicate that the larger suspended span could consume more seismic energy and result in smaller horizontal displacement and acceleration. Moreover, the comparison results also point out that the existence of the suspension part showed better seismic energy dissipation capacity compared to the normal framed structure, and two symmetrical suspension parts also performed better than a single asymmetrical part in seismic energy dissipation.

The substrate pH directly affects nutrient availability in the rhizosphere and nutrient uptake by plants. Macronutrients such as nitrogen, potassium, calcium, magnesium, and sulfur are highly available at pH 6.0–6.5, while micronutrients become less available at higher, alkaline pH (pH > 7.0). Recent research has indicated that low pHs can enhance nutrient uptake and improve sweet orange (Citrus sinensis) tree health. We designed a study to understand the influence of a wide range of substrate pH values on plant size and biomass, nutrient availability, leaf gas exchange, and rhizosphere microbiome of grapefruit (Citrus paradisi) affected by Huanglongbing (HLB). Two-year-old “Ray Ruby” grapefruit plants grafted on sour orange (Citrus aurantium) rootstock were cultivated indoors in 10-cm wide × 40-cm tall pots with peat:perlite commercial substrate (80:20 v/v). We tested two disease statuses [HLB-free or healthy (negative, HLB–) and HLB-affected (positive, HLB+)] and six substrate pH values (4, 5, 6, 7, 8, 9) in a 2 × 6 factorial arranged on a complete randomized design with four replications. The canopy volume of HLB+ plants was 20% lower than healthy plants, with pHs 7 and 9 resulting in 44% less canopy volume. The root and shoot ratio of dry weight was 25.8% lower in HLB+ than in healthy plants. Poor root growth and a decrease in fibrous roots were found, especially in pH 5 and 6 treatments in HLB+ plants (p < 0.0001). The disease status and the substrate pHs influenced the leaf nutrient concentration (p < 0.05). High substrate pH affects nutrient availability for root uptake, influencing the nutrient balance throughout the plant system. pH values did not affect plant photosynthesis, indicating that pH does not recover HLB+ plants to the photosynthetic levels of healthy plants—even though high pH positively influenced internal CO2. There were collectively over 200 rhizobacterial identified by the 16S rRNA gene sequencing in individual phylogenetic trees. Most rhizobacteria reads were identified in pH 9. Our results indicated no effect of substrate pHs on the plant disease status induced by enhanced nutrient uptake.

Citrus Huanglongbing (HLB) is a serious disease for the citrus industry. Earlier studies showed that ampicillin (Amp) can reduce titers of the pathogen which causes HLB and the bacteria Candidatus Liberibacter asiaticus (CLas) in HLB-affected citrus. CLas has not yet been cultured, so the mechanisms of Amp against CLas are unclear. Some chemicals were demonstrated to trigger citrus defense systems against CLas. Therefore, we hypothesize that Amp may induce citrus defenses against CLas. Here we applied three nano-formulations of varying droplet sizes to HLB-affected citrus to achieve different accumulated concentrations of Amp (high, medium, low) in the plants. We then used RNA-seq to analyze induction of gene expression of citrus defense systems against CLas in response to different concentrations of Amp. The results indicated that at all accumulated concentrations of Amp can significantly suppress CLas titer and mitigate HLB symptoms. Transcriptomic analyses showed that Amp treatment induced expression of heat shock proteins (Hsps) in HLB-affected citrus, and these Hsps were significantly related to several defense genes encoding R proteins, transcription factors, splicing factors, RNA-binding proteins, RNA-dependent RNA polymerase, Gibberellic acid methyltransferase 2, L-ascorbate peroxidase 2, and ferruginol synthase that confer tolerance to CLas in citrus plants. Taken together, these results suggest that Amp treatment of citrus plants can trigger expression of Hsps and related defense genes to respond to CLas infection. These findings are valuable for developing novel strategies to combat citrus HLB.

Cancer has become a common disease that seriously endangers human health and life. Up to now, the essential treatment method has been drug therapy, and drug delivery plays an important role in cancer therapy. To improve the efficiency of drug therapy, researchers are committed to improving drug delivery methods to enhance drug pharmacokinetics and cancer accumulation. Supramolecular coordination complexes (SCCs) with well-defined shapes and sizes are formed through the coordination between diverse functional organic ligands and metal ions, and they have emerged as potential components in drug delivery and cancer therapy. In particular, micelles or vesicles with the required biocompatibility and stability are synthesized using SCC-containing polymeric systems to develop novel carriers for drug delivery that possess combined properties and extended system tunability. In this study, the research status of SCC-containing polymeric systems as drug carriers and adjuvants for cancer treatment is reviewed, and a special focus is given to their design and preparation.

Citrus huanglongbing (HLB) is a devastating disease for the citrus industry. The previous studies demonstrated that oxytetracycline and penicillin are effective antibiotics against Candidatus Liberibacter asiaticus (CLas). However, since CLas is uncultured, the mechanisms of action of antibiotics against CLas are still unclear. It was recently reported that the endophytic microbial communities are associated with the progression of citrus HLB after oxytetracycline and penicillin treatment. Therefore, we hypothesize that penicillin has greater antibacterial activity against CLas than oxytetracycline, which may be associated with the alteration of the structure and function of endophytic microbial communities in HLB-affected citrus in response to these antibiotics. To test this hypothesis, the microbiome of HLB-affected citrus leaves treated with these two antibiotics was analyzed using a metagenomic method. Our results indicate that the microbial structure and function in HLB-affected citrus were altered by these two antibiotics. The relative abundance of beneficial bacterial species, including Streptomyces avermitilis and Bradyrhizobium, was higher in penicillin-treated plants compared to those treated with oxytetracycline, and the relative abundance of the bacterial species (such as Propionibacterium acnes and Synechocystis sp PCC 6803) associated with CLas survival was lower for penicillin-treated plants compared to oxytetracycline-treated plants. These results indicate that penicillin has greater antibacterial activity against CLas. Based on the metagenomic analysis, this study elucidated the mechanism for the observed increase in antibacterial activity of penicillin against CLas. The data presented here are not only invaluable for developing eco-friendly and effective biocontrol strategies to combat citrus HLB, but also provide a method for revealing mechanism of antimicrobial against uncultured bacteria in host.

神经酸是一种能够疏通、修复受损神经纤维和促进神经细胞再生的单不饱和脂肪酸，可用于预防及治疗脑萎缩、阿尔茨海默病等脑疾病，具有较高的药用价值。旨在为高纯度神经酸产品的生产和发展提供参考，综述了神经酸的功效和来源，详细阐述了植物来源神经酸的分离方法，包括其原理和特点。不同分离方法的耦合可克服单一分离方法的某些缺点，且一定程度上解决对神经酸纯度、产量双重提高的难题，成为重要的研究方向。Nervonic acid is a monounsaturated fatty acid that can unblock and repair damaged nerve fibers and promote nerve cell regeneration, so it can be used to prevent and treat brain diseases such as brain atrophy and Alzheimer′s disease, and has high medicinal value. In order to provide reference for the production and development of high-purity nervonic acid products, the efficacy and sources of nervonic acid were reviewed, and the separation methods of nervonic acid, including their principles and characteristics were described. The coupling of different methods can overcome some disadvantages of single separation method, solve the problem of improving the purity and yield of nervonic acid to a certain extent, which has become an important research direction for the separation of nervonic acid.

Usually, radon detector must be calibrated every year, commonly used solid radon source calibration method and radon chamber calibration method. The former has the problems of radon source device aging, complex operation and radioactive substances vulnerable to transport control. The latter has problems such as calibration time principal and inability to achieve on-site calibration. Based on the above facts, this paper proposes an experimental method for the calibration of radon measuring instrument using uranium waste rock, which is used to realize the field calibration of seismic radon measuring instrument. The results show that the radon concentration control method has high accuracy and stability, and the relative error between the output gas radon concentration and the preset target is 1%. The comparison between the calibration experiment of uranium mine waste rock and the calibration experiment of standard radon chamber shows that the calibration values of the calibration coefficient of the two are in good agreement, the relative error is only 1.14%, and the normalized error En is only 0.135 6, which is within the expected range. It can provide theoretical support for the subsequent development of portable radon detector calibration device.