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Patients with inflammatory bowel disease (IBD) are susceptible to Clostridioides difficile infection (CDI), resulting in poor outcomes and recurrence; therefore, the molecular characterization of C. difficile in IBD patients in China needs further investigation.C. difficile strains were isolated and identified from faecal samples of adult and paediatric IBD patients. Toxigenic strains were typed using multilocus sequence typing and whole genomic sequencing (WGS) to construct the phylogenetic tree. Susceptibility to 10 antimicrobials was evaluated using the Etest.Among the 838 IBD patients, 82 toxigenic C. difficile were identified, which comprised 46 from adults and 36 children. A total of 90.2% (74/82) of the isolates were positive for both toxin A and toxin B genes (A+B+), whereas the remaining 9.8% were negative for toxin A gene but positive for toxin B gene (A-B+). These toxigenic strains were susceptible to metronidazole and vancomycin, but highly resistant to clindamycin, erythromycin, and fluoroquinolones. All moxifloxacin-resistant isolates had mutations resulting in an amino acid substitution in gryA (T82I). The dominant types were ST-35 (20.7%), ST-2 (17.1%), ST-54 (13.4%), and ST-3 (13.4%) in all patients.The incidence and molecular epidemiology of C. difficile infection in adult IBD patients resembled CDI in the general inpatient population. A higher antibiotic resistance rate was identified among the C. difficile isolates obtained from paediatric IBD patients than from adult patients, and a few STs accounted for most multidrug-resistant strains. However, the molecular genetic features of the same ST type between these two groups remains highly correlated.

Carbapenemase-producing Enterobacteriaceae (CPE) isolates are recognized as one of the most severe threats to public health. However, the population structure and genetic characteristics of CPE isolates among bloodstream infections (BSIs) are largely unknown. To address this knowledge gap, in this study, we included patients with clinically significant BSIs due to Enterobacterales isolates, recruited from 26 sentinel hospitals in China (2014–2015). CPE isolates were microbiologically and genomically characterized, including their susceptibility profiles, molecular typing, phylogenetic features, and genetic context analysis of carbapenemase-encoding genes. Of the 2569 BSI Enterobacterales isolates enrolled, 42 (1.6%) were carbapenemase-positive. Moreover, among the 2242 investigated isolates, 1111 (49.6%) extended-spectrum β-lactamase (ESBL)-producing isolates were identified in Escherichia (E.) coli, Klebsiella (K.) pneumoniae, Proteus (P.) mirabilis, and K. oxytoca. Whole genome sequencing analysis showed the clonal spread of K. pneumoniae carbapenemase (KPC)-2-producing K. pneumoniae sequence type 11 (ST11) and New Delhi metallo-β-lactamase (NDM)-5-producing E. coli ST167 in our collection. Plasmid analysis revealed that carbapenemase-encoding genes were located on multiple plasmids. A high prevalence of biofilm-encoding type 3 fimbriae clusters and yesiniabactin-associated genes was observed in K. pneumoniae isolates. This work demonstrates the high prevalence of ESBLs and the wide dissemination of CPE among BSI isolates in China, which represent real clinical threats. Moreover, our findings first illustrate a more comprehensive genome scenario of CPE isolates among BSIs. The clonal spread of KPC-2-producing K. pneumoniae ST11 and NDM-5-producing E. coli ST167 needs to be closely monitored.

The wettability of 3 mol% yttria-stabilized zirconia (3YSZ) by molten Cu was noticeably improved by applying a direct current (DC). Furthermore, robust brazing of 3YSZ to a GH3128 superalloy using a Cu filler was achieved within seconds at 1100 °C with the assistance of a DC. When the DC flowed from 3YSZ to GH3128, the shear strength of the joints reached 225 ± 20 MPa at 1 s of energization and increased to 330 ± 30 MPa at 5 s of energization. The formation of Cu51Zr14 at the 3YSZ/Cu interface, the dissolution of Ni into the Cu filler, the dispersive distribution of fine granular (Mo, Cr, W)(Ni, Cu) in the brazing seam and the relief of residual stress by ductile (Cu, Ni) solid solution were crucial for achieving the high-strength joints. This work provides a novel and economical method for ultrafast brazing of zirconia to metals.

The wettability of 3 mol% Y2O3-stabilized ZrO2 (3YSZ) by molten Cu can be greatly improved by applying pulsed currents at 1373 K. The improvement was closely related to current polarity and influenced by duty cycle and frequency. When the Cu/3YSZ interface was under cathodic condition, the wettability was mainly improved by the formation of substoichiometric ZrO2-δ and metallic Zr at the interface. Increasing duty cycle caused the interface to change from forming protrusions to creating depression. Decreasing frequency further deepened the depression. In the opposite polarity, the adsorption and enrichment of oxygen reduced the solid-liquid and liquid-vacuum interfacial energies, thus improving the wettability. Only bubbles formed at the interface. The larger the duty cycle, the more rapidly bubbles formed and escaped. The effect of frequency at this polarity was weak. Overall, this work provides a novel and effective strategy for tailoring the wettability and interfacial chemistry between zirconia and metals.

Conventional reactive air brazing (RAB) of stainless steel (SS) to ceramic components usually encounters Cr oxidation and joint embrittlement problems due to high temperature and long dwelling time. Herein, 3 mol% yttria-stabilized zirconia (3YSZ) and 430 SS were joined using an Ag–CuO filler in seconds at relatively low temperatures (875 °C–1050 °C) with the assistance of a direct current passing through the seam. The applied current promoted the melting of the filler and rapid filling of the gap due to Joule heating effect. Also, it facilitated atomic/ionic transport and interfacial reaction. Key joining parameters including current density, joining time and furnace temperature were investigated, and a maximum joint strength of 158 ± 9 MPa was achieved at a current density of 4 A/cm2 for 30 s at 950 °C, which is approximately 50% higher than that of the RAB joints. The formation of AgCu4Zr and Zr-rich intermetallic phases at the 3YSZ/Ag and Ag/430 SS interfaces, respectively, together with the suppression of the growth of Cr-containing oxide, was responsible for the robust joining.

Two previously undescribed 3(4), 8(9), 9(10)-trisecocycloartane triterpene dilactones with a featured eleven-membered ring, pseudoladilactones A and B (1-2), together with three known ones (4-5), were isolated from the 80 % ethanol extract of the cones of Pseudolarix amabilis. The structures of compounds 1 and 2 were determined on the basis of analysis of 1D- and 2D-NMR spectroscopic data. The absolute configuration of pseudoladilactones A (1) was elucidated by single crystal X-ray diffraction (CuKα). All isolates were tested for cytototoxicity against four human tumor cell lines A549, HCT116, SK-BR-3, and HepG2.

Rare-earth zirconate ceramics are conventionally sintered at high temperatures for long durations to achieve a full density. Herein, we synthesized and densified five lanthanide-group rare-earth zirconates (Ln2Zr2O7, Ln = La, Nd, Sm, Eu, Gd) containing different numbers of Ln cations in a high-throughput mode using a novel ultrafast high-temperature sintering technique within a cycle of 5 min, and investigated the effects of components on the structure and properties of the resultant ceramics. Under the high-throughput mode, the same sintering conditions make the analysis and comparison of the results more reasonable. The average grain size decreased while hardness and Young’s modulus increased with an increase in the number of the Ln components in the zirconate ceramics. The mechanisms were ascribed to the sluggish diffusion and lattice distortion effect caused by the increase in entropy.

We investigated the wetting of a high-entropy rare-earth oxide, (La0.2Nd0.2Sm0.2Eu0.2Gd0.2)2Zr2O7, by a molten 71Ag–27Cu–2Ti (in wt%) alloy using a modified sessile drop method at 1073–1273 K. The wettability shows a first increase and then decrease with increasing temperature, depending on the competition among the adsorption and diffusion of active Ti atoms towards triple line, the consumption of Ti due to interfacial reaction and the migration of oxygen from the substrate bulk to the interface. In addition, the La cations in the high-entropy substrate exhibited noticeable outward diffusion while the other rare-earth cations remained stable due to their different bonding strengths in the lattice. Despite the occurrence of interfacial reaction and selective diffusion, the substrate maintained the high-entropy structure after the reactive wetting.

Dexmedetomidine sedation has been associated with favourable outcomes after surgery. We aimed to assess whether perioperative dexmedetomidine use is associated with improved survival after cardiac surgery.This retrospective cohort study included 2068 patients undergoing on-pump coronary artery bypass grafting and/or valve surgery. Among them, 1029 patients received dexmedetomidine, and 1039 patients did not. Intravenous dexmedetomidine infusion of 0.007 μg kgThe median age was 63 yr old and the male to female ratio was 71:29 in both groups. Baseline covariates were balanced between groups after adjustment using PSM, IPTW, or overlap weighting. Patients receiving dexmedetomidine in cardiac surgical procedures had higher survival during postoperative 5 yr in unadjusted analysis (hazard ratio [HR]=0.63; 95% confidence interval [CI], 0.51-0.78; P0.001), and after adjustment with PSM (HR=0.63; 95% CI, 0.45-0.89; P=0.009), IPTW (HR=0.70; 95% CI, 0.51-0.95; P=0.023), or overlap weighting (HR=0.67; 95% CI, 0.51-0.89; P=0.006). The 5-yr mortality rate after cardiac surgery was 13% and 20% in the dexmedetomidine and non-dexmedetomidine groups, respectively (PSM adjusted odds ratio=0.61; 95% CI, 0.42-0.89; P=0.010).Perioperative dexmedetomidine infusion was associated with improved 5-yr survival in patients undergoing cardiac surgery.

We achieved the densification of hydroxyapatite (HA) via cold sintering using CaHPO4·2H2O as an additive at temperatures lower than 200 °C and investigated the influences of CaHPO4·2H2O content and temperature on the relative density of cold-sintered HA and its composites. The elastic modulus, compressive strength and flexural strength of the cold-sintered specimens were comparable yet slightly inferior to the level of the dense HA prepared by conventional sintering at temperatures higher than 1000 °C. A possible densification mechanism was proposed for the formation of hydrogen bonds between the CaHPO4 fragments generated by the thermal decomposition of CaHPO4·2H2O and the phosphate groups in HA by water molecules, thus linking the HA particles together. This strategy of achieving dense target product from its hydrated precursors provides an important avenue for the development of cold sintering process.

Objective To assess the therapeutic effect of platelet-rich plasma (PRP) for moderate-to-severe carpal tunnel syndrome (CTS). Design A prospective, randomized, double-blinded, controlled trial (1-year follow-up). Setting Outpatient of local medical center settings. Participants Patients (N=26) who were diagnosed with bilateral moderate-to-severe CTS (total 52 wrists) were included. For each patient, one wrist was randomized into either the PRP or control group and the contralateral wrist of the same patient was allocated to another group. Twenty-four patients were included in the final data analysis. Interventions The wrists in the PRP group received a single ultrasound-guided dose of PRP injection (3.5mL), and the control group received a single ultrasound-guided injection with normal saline (3.5mL). Main Outcome Measures The Boston Carpal Tunnel Syndrome Questionnaire (BCTQ) scores were used as the primary outcome. Secondary outcomes encompassed the cross-sectional area of the median nerve and electrophysiological study. Assessments were conducted prior to injection and 1, 3, 6, and 12 months postinjection. Results Compared to the control group, the PRP group exhibited significant improvements in BCTQ severity scores at all time points, BCTQ functional scores at the sixth month, and cross-sectional area at the 12th month postinjection (P Conclusions A single dose of ultrasound-guided perineural PRP injection can provide therapeutic effect for 1 year postinjection.

Pyrochlore-type high-entropy oxides (HEOs) are usually sintered at high temperatures for a long time to achieve full density. Herein, we synthesized pyrochlore-structured (La0.2Nd0.2Sm0.2Eu0.2Gd0.2)2Zr2O7 HEOs with densities up to 99 % at a furnace temperature of 1200 °C in seconds via reactive flash sintering (RFS). The resultant HEOs achieved compositional uniformity at the atomic level and exhibited superior modulus, hardness and fracture toughness compared to the counterparts prepared by conventional solid-state sintering (at 1600 °C for 6 h). The underlying mechanisms for the ultrafast densification of the RFSed-HEOs were addressed in view of the roles of electric field, rapid heating, external pressure and internal reactions.

Hydroxyapatite (HA)/magnesium (Mg) composites are a promising alternative material for bone repair in load-bearing sites. However, the poor wettability between Mg and HA as well as the extreme sensitivity of Mg to oxidation and high vapor pressure at elevated temperatures makes the preparation of HA/Mg composites rather difficult. Herein, a facile strategy for improving the wettability of HA by Mg was proposed to enable the successful preparation of bio-inspired HA/Mg composites via directional freezing and pressureless infiltration. SiO2 nanoparticles were introduced into the freeze-cast HA scaffold by doping or soaking to promote the spontaneous infiltration of the Mg melt. The resulting HA/Mg composites displayed a delicate biomimetic lamellar structure with alternating ceramic/metal arrangements and demonstrated higher compressive strength (increased by 140%) and wear resistance (increased by 1200%) than porcine bones. In addition, the composites exhibited progressive degradation and surface apatite mineralization in a simulated body fluid environment, making them potentially promising for biomedical applications. This study provides a facile and tailorable method for the design and preparation of novel Mg-matrix composites with bio-inspired structures and biomedical functions.

Conventional ceramic sintering often requires high temperatures and hours of duration to achieve near full density. Herein, we adopted an innovative ultrafast high-temperature sintering (UHS) technique to densify several representative bulk oxides within an isothermal duration of 30 s and a total sintering period of several minutes, and revealed the relationship between ceramic structures and processing parameters. These achievements demonstrate the great potential of the UHS technique in the rapid densification of ceramics. Moreover, this flexible technique is expected to accelerate the material screening rate and facilitate the development of novel materials.

Plumbago auriculata Lam., a typical distylous plant, undergoes heteromorphic self-incompatibility (HetSI). The use of in vitro flowering allows the early identification of a plant's style morphology, and this process can be used to increase the efficiency of the breeding process and expedite research on the flowering mechanisms of P. auriculata. Here, we used seeds of P. auriculata as explants; obtained plantlets; and assessed the effects of temperature, thermoperiod, photoperiod, and light intensity on the in vitro flowering of the plants. The optimum temperature treatment was a diurnal alternation of 35 °C for 12 h and 25 °C for 12 h. Under these conditions, flower bud formation occurred within approximately 33 d, and the flowering percentage was as high as 91%. A photoperiod of 16 h and a light intensity of 200 µmol m−2 s−1 also promoted in vitro flowering. Under these conditions, flower buds formed within approximately 33 d, and the flowering percentage was approximately 90%. However, relatively long photoperiods and high light intensity suppressed flower bud development, reduced flowering, and shortened flower lifespan. The in vitro flowers had a lighter colour and smaller petals than did the in vivo flowers, although their floral structures (including their reproductive structures) were intact. This work demonstrates a stable system for the induction of in vitro flowering in P. auriculata and describes suitable temperature (35 °C/25 °C) and light (16 h photoperiod and 200 µmol m−2 s−1) conditions for rapid in vitro flowering. This system allows the efficient identification of long and short P. auriculata morphs and allows the formulation of a reasonable cultivation plan. The methods described here provide technical support for the development, utilization, and rapid propagation of excellent new P. auriculata varieties.

In nature, many different factors cause plants to present variegated leaves. The purpose of this study was to reveal the changes in the green and albino leaves of Hydrangea macrophylla 'Maculata'. It was found that in the albino zone, the leaves became thinner, the chloroplast structure disappeared, and a large number of leucoplasts replaced chloroplasts. In addition, the albino zone of the leaves contained almost no chlorophyll and showed no function related to transforming and utilizing light energy, and more intense oxidative stress was observed in the albino zone of the leaves than in the green zone. RNA-seq analysis showed that the chlorophyll synthesis pathway of the albino zone of leaves was blocked. Upregulated expression of the hydrangea ringspot virus (HdRSV) coat protein (CP) gene was detected in albino tissue by RT-qPCR. Finally, combined UPLC-MS/MS and RNA-seq analyses revealed metabolic changes involving multiple pathways in albino leaf tissue, centered on the TCA cycle. We hypothesize that HdRSV may alter energy metabolism in the albino zone of leaves, including increased lipid metabolism, reduced sugar metabolism, and increased synthesis of amino acids and the viral capsid protein from ribosomes.

Medium- and high-temperature phase change materials are important in the field of heat storage. They usually consist of inorganic salt/ceramic mixtures and require high temperatures for sintering. In this work, cold sintering was applied to fabricate heat storage composites using NaNO3/MgO as a model system. NaNO3 was successfully encapsulated in a MgO skeleton, which maintained stable after 500 melting−freezing cycles. The composites exhibited excellent chemical compatibility and good thermal stability. Moreover, the resultant composites achieved a compressive strength of higher than 100 MPa with relative density over 98% under 75 MPa at low temperatures (≤180 °C) in the presence of 6 wt% water. Compared with the conventional preparation processes that are implemented at high temperatures, this method is very simple, economical and environmentally friendly, and can be applied to the synthesis of other inorganic salt/ceramic phase change materials.

We designed a soft Cu-based brazing filler (60Cu–40Ag in wt.%) and investigated its wettability and brazeability with 3 mol% yttria-stabilized zirconia (3YSZ) under direct current (DC) application. Increasing the current intensity dramatically accelerated the spreading rate and decreased the final contact angle. When the DC reached 60 mA, the contact angle decreased from 140° to 50° within 50 s and finally stabilized at 26° in approximately 300 s. The change in the stoichiometry of the 3YSZ substrate and the adsorption of Zr at the triple line were presumably responsible for the electrochemically induced wetting improvement. Furthermore, robust joining of 3YSZ to 304 stainless steel (304 SS) with a shear strength of 215 ± 9 MPa was achieved in only 300 s by applying a DC of 30 mA using this 60Cu–40Ag filler. The AgCu4Zr formed at the 60Cu–40Ag/3YSZ interface was critical for the robust joining. This work provides a novel route for obtaining robust zirconia–metal joints.

We constructed a nacre-inspired laminate-reticular hierarchical architecture in Cu/(TiC−Cr3C2) composites by tuning the wettability between loose freeze-cast ceramic lamellae and Cu melt. This unique architecture takes full advantage of superb intrinsic strength of the ceramic particles and toughness of the metal, stimulating multiple extrinsic toughening mechanisms such as synergistic deformation of the metal and ceramic layers, ductile-ligament bridging and multi-cracking mode. As a consequence, the resultant composites containing ~30 vol% ceramics exhibited exceptional damage-tolerant properties with a fracture toughness of 62.6 ± 1.0 MPa⋅m1/2 and a bending strength of 639 ± 27 MPa.

A nacre-like magnesium matrix composite with high carbon nanotube (CNT) contents (up to 4.40 wt%) was successfully prepared under the combined effects of bidirectional freeze casting, pressureless infiltration, and hot pressing. The bidirectional freeze casting was carried out to fabricate large-scale parallelly layered CNT scaffolds. The spontaneous infiltration of an AZ91 magnesium alloy was achieved using nano-silica as the wetting promoter, and MgO and Mg2Si (reaction products) provided the strength of the as-synthesized composites. Furthermore, the hot pressing increased the average thickness ratio of reinforcing phase/alloy layers in the AZ91/CNT composites from 0.89 (before hot pressing) to 1.46 (after hot pressing) and also significantly improved the specific strength from 142.3 MPa/(g⋅cm−3) to 158.7 MPa/(g⋅cm−3) without sacrificing the specific toughness ((17–18) MPa⋅m1/2/(g⋅cm−3)). The resultant composites were mainly strengthened by CNTs, reaction products, and the strong interfacial bonding between CNTs and the Mg matrix. The key toughening mechanisms for the as-prepared composites were crack deflection, branching, and CNT pull-out. This study provides a new idea for the economical and efficient preparation of lightweight and damage-tolerant composites with high CNT contents.

High-density hydroxyapatite (HA) compacts were achieved by cold sintering of co-precipitated powders at temperatures lower than 200 °C without addition of any solvent. Critical factors affecting the densification behavior including the source of powders, the type of solvent, applied pressure, sintering temperature and time were investigated. The presence of lattice water together with ion substitution in the co-precipitated HA powders has a significant effect on the densification. A novel viewpoint that is essentially different from classical dissolution−precipitation mechanism in cold sintering was proposed; i.e., the formation of hydrogen bonds between the HA particles plays a critical role in the densification.

Semitransparent polymer solar cells (ST-PSCs) have attracted worldwide attention owing to unique superiority in multiple utilization of incident light. However, the color of ST-PSCs is relatively uniform after fabrication, cannot be dynamically tuned in terms of application requirement. Herein, we demonstrate a high-efficiency ST-PSCs as a smart window, which can be reversibly switched on and off by a gasochromic tungsten trioxide/platinum (WO3/Pt) back reflector layer. The ST-PSCs can be switchable between colored and bleached states with fast response speed of sub-second during hydrogen exposure. Meanwhile, the color and transparency-switching enable light trapping enhancement in long wavelength range, which can systematically improve power conversion efficiency (PCE). As a result, the ST-PSCs contribute a PCE of 10.2% and 9.1% as well as corresponding average visible transmission (AVT) of 25.4% and 33.8% at colored state and bleached state, respectively, which can meet the visual aesthetics requirement well in building integrated photovoltaics. To the best of our knowledge, this is the first example for ST-PSCs that achieve both color-switching and light trapping. Furthermore, the smart windows facing to automobile sunroof are proposed to prove a practical application towards commercialization. We believe that smart windows with gasochromic functions can promise potential opportunities and directions for the future development of ST-PSCs.

Neuroblastoma (NB) is a sympathetic nervous system tumor and one of the most common pediatric, extra-cranial, solid tumors, especially in early childhood. Its expression is heterogeneous and shows a unique clinical and prognostic feature. Due to its insidious onset, most diagnoses are accompanied by metastasis, making patient prognoses extremely poor. Novel biomarkers are urgently needed for easy diagnosis, metastasis detection, and investigation of potential mechanisms regulating NB tumor progression. Recent research highlights that circulating tumor markers could be used to diagnose and monitor prognosis in various tumors. Among them, exosomal genetic material has attracted much attention because of its tumor-secreted specificity and unique mechanism of action. In this study, we used next-generation sequencing to study PIWI-interacting RNAs (piRNAs) in exosomes derived from NB patient plasma. We found higher human piRNA 1089 (hsa-piR-1089) levels in exosomes from NB patients than from normal controls. Our receiver operating characteristic (ROC) curve analyses showed that hsa-piR-1089 had high diagnostic sensitivity and specificity. We also found that high hsa-piR-1089 expression in NB tumor tissues was associated with a high-risk Children's Oncology Group classification and metastasis. Our in vitro experiments showed that exosomal hsa-piR-1089 promoted NB cell proliferation and migration by inhibiting Kelch-like ECH-associated protein 1 (KEAP1) expression. Moreover, low KEAP1 expression was associated with NB progression in clinical samples. In conclusion, our data indicate that blood-borne exosomal hsa-piR-1089 is a diagnostic marker for NB and assessing metastasis. Our study provides a quick, simple, and noninvasive diagnostic method for NB and contributes to developing new treatment strategies.