Topology Reconfiguration of Anion-Pillared Metal-Organic Framework from Flexibility to Rigidity for Enhanced Acetylene Separation.

Flexible metal-organic framework (MOF) adsorbents commonly encounter limitations in removing trace impurities below gate-opening threshold pressures. Topology reconfiguration can fundamentally eliminate intrinsic structural flexibility, yet remains a formidable challenge and is rarely achieved in practical applications. Herein, a solvent-mediated approach is presented to regulate the flexible CuSnF6-dpds-sql (dpds = 4,4''-dipyridyldisulfide) with sql topology into rigid CuSnF6-dpds-cds with cds topology. Notably, the cds topology is unprecedented and first obtained in anion-pillared MOF materials. As a result, rigid CuSnF6-dpds-cds exhibits enhanced C2H2 adsorption capacity of 48.61 cm3 g-1 at 0.01 bar compared to flexible CuSnF6-dpds-sql (21.06 cm3 g-1). The topology transformation also facilitates the adsorption kinetics for C2H2, exhibiting a 6.5-fold enhanced diffusion time constant (D/r2) of 1.71 × 10-3 s-1 on CuSnF6-dpds-cds than that of CuSnF6-dpds-sql (2.64 × 10-4 s-1). Multiple computational simulations reveal the structural transformations and guest-host interactions in both adsorbents. Furthermore, dynamic breakthrough experiments demonstrate that high-purity C2H4 (>99.996%) effluent with a productivity of 93.9 mmol g-1 can be directly collected from C2H2/C2H4 (1/99, v/v) gas-mixture in a single CuSnF6-dpds-cds column.

Brachytherapy in craniopharyngiomas: a systematic review and meta-analysis of long-term follow-up.

OBJECTIVE: Brachytherapy has been indicated as an alternative option for treating cystic craniopharyngiomas (CPs). The potential benefits of brachytherapy for CPs have not yet been clarified. The purpose of this work was to conduct a meta-analysis to analyze the long-term efficacy and adverse reactions profile of brachytherapy for CPs. MATERIALS AND METHODS: The relevant databases were searched to collect the clinical trials on brachytherapy in patients with CPs. Included studies were limited to publications in full manuscript form with at least 5-year median follow-up, and adequate reporting of treatment outcomes and adverse reactions data. Stata 12.0 was used for data analysis. RESULTS: According to the inclusion and exclusion criteria, a total of 6 clinical trials involving 266 patients with CPs were included in this meta-analysis. The minimum average follow-up was 5 years. The results of the meta-analysis showed that 1-year, 2-3 years and 5 years progression free survival rates (PFS) are 75% (95%CI: 66-84%), 62% (95%CI: 52-72%) and 57% (95%CI: 22-92%), respectively. At the last follow-up, less than 16% of patients with visual outcomes worser than baseline in all included studies. While, for endocrine outcomes, less than 32% of patients worser than baseline level. CONCLUSION: In general, based on the above results, brachytherapy should be considered as a good choice for the treatment of CP.

Restoring colistin sensitivity in colistin-resistant Salmonella and Escherichia coli: combinatorial use of berberine and EDTA with colistin.

The appearance and prevalence of multidrug-resistance (MDR) Gram-negative bacteria (GNB) have limited our antibiotic capacity to control bacterial infections. The clinical efficacy of colistin (COL), considered as the "last resort" for treating GNB infections, has been severely hindered by its increased use as well as the emergence and prevalence of mobile colistin resistance (MCR)-mediated acquired drug resistance. Identifying promising compounds to restore antibiotic activity is becoming an effective strategy to alleviate the crisis of increasing MDR. We first demonstrated that the combination of berberine (BBR) and EDTA substantially restored COL sensitivity against COL-resistant Salmonella and Escherichia coli. Molecular docking indicated that BBR can interact with MCR-1 and the efflux pump system AcrAB-TolC, and BBR combined with EDTA downregulated the expression level of mcr-1 and tolC. Mechanically, BBR combined with EDTA could increase bacterial membrane damage, inhibit the function of multidrug efflux pump, and promote oxidative damage, thereby boosting the action of COL. In addition, transcriptome analysis found that the combination of BBR and EDTA can accelerate the tricarboxylic acid cycle, inhibit cationic antimicrobial peptide (CAMP) resistance, and attenuate Salmonella virulence. Notably, the combination of BBR and EDTA with COL significantly reduced the bacterial load in the liver and spleen of a mice model infected with Salmonella. Our findings revealed that BBR and EDTA can be used as adjuvants collectively with COL to synergistically reverse the COL resistance of bacteria. IMPORTANCE: Colistin is last-resort antibiotic used to treat serious clinical infections caused by MDR bacterial pathogens. The recent emergence of transferable plasmid-mediated COL resistance gene mcr-1 has raised the specter of a rapid worldwide spread of COL resistance. Coupled with the fact of barren antibiotic development pipeline nowadays, a critical approach is to revitalize existing antibiotics using antibiotic adjuvants. Our research showed that berberine combined with EDTA effectively reversed COL resistance both in vivo and in vitro through multiple modes of action. The discovery of berberine in combination with EDTA as a new and safe COL adjuvant provides a therapeutic regimen for combating Gram-negative bacteria infections. Our findings provide a potential therapeutic option using existing antibiotics in combination with antibiotic adjuvants and address the prevalent infections caused by MDR Gram-negative pathogens worldwide.

Molecular sieving of iso-butene from C4 olefins with simultaneous high 1,3-butadiene and n-butene uptakes.

Iso-butene (iso-C4H8) is an important raw material in chemical industry, whereas its efficient separation remains challenging due to similar molecular properties of C4 olefins. The ideal adsorbent should possess simultaneous high uptakes for 1,3-butadiene (C4H6) and n-butene (n-C4H8) counterparts, endowing high efficiency for iso-C4H8 separation in adsorption columns. Herein, a sulfate-pillared adsorbent, SOFOUR-DPDS-Ni (DPDS = 4,4'-dipyridyldisulfide), is reported for the efficient iso-C4H8 separation from binary and ternary C4 olefin mixtures. The rigidity in pore sizes and shapes of SOFOUR-DPDS-Ni exerts the molecular sieving of iso-C4H8, while exhibiting high C4H6 and n-C4H8 uptakes. The benchmark Henry's selectivity for C4H6/iso-C4H8 (2321.8) and n-C4H8/iso-C4H8 (233.5) outperforms most reported adsorbents. Computational simulations reveal the strong interactions for C4H6 and n-C4H8. Furthermore, dynamic breakthrough experiments demonstrate the direct production of high-purity iso-C4H8 (>99.9%) from C4H6/iso-C4H8 (50/50, v/v), n-C4H8/iso-C4H8 (50/50, v/v), and C4H6/n-C4H8/iso-C4H8 (50/15/35, v/v/v) gas-mixtures.

1D Pb halide perovskite-like materials for high performance X-ray detection.

The strategy of bandgap regulation is important for X-ray detection, but has not been reported for 1D Pb halide perovskite materials. In this work, three such materials, 1, 2 and 3, with a tunable bandgap, were fabricated for application in X-ray detection. 3 shows high sensitivity, far superior to commercial X-ray detectors.

Selective Control of Phases and Electronic Structures of Monolayer TaTe2.

Transition metal dichalcogenide (TMDC) films exhibit rich phases and superstructures, which can be controlled by the growth conditions as well as post-growth annealing treatment. Here, the selective growth of monolayer TaTe2 films with different phases as well as superstructures using molecular beam epitaxy (MBE) is reported. Monolayer 1H-TaTe2 and 1T-TaTe2 films can be selectively controlled by varying the growth temperature, and their different electronic structures are revealed through the combination of angle-resolved photoemission spectroscopy measurements (ARPES) and first-principles calculations. Moreover, post-growth annealing of the 1H-TaTe2 film further leads to a transition from a 19 × 19 $\sqrt {19}{\times }\sqrt {19}$ superstructure to a new 2 × 2 superstructure, where two gaps are observed in the electronic structure and persist up to room temperature. First-principles calculations reveal the role of the phonon instability in the formation of superstructures and the effect of local atomic distortions on the modified electronic structures. This work demonstrates the manipulation of the rich phases and superstructures of monolayer TaTe2 films by controlling the growth kinetics and post-growth annealing.

Thermally Activated Delayed Fluorescence (TADF)-active Coinage-metal Sulfide Clusters for High-resolution X-ray Imaging.

The study of facile-synthesis and low-cost X-ray scintillators with high light yield, low detection limit and high X-ray imaging resolution plays a vital role in medical and industrial imaging fields. However, the optimal balance between X-ray absorption, decay lifetime and excitonic utilization efficiency of scintillators to achieve high-resolution imaging is extremely difficult due to the inherent contradiction. Here two thermally activated delayed fluorescence (TADF)-actived coinage-metal clusters M6 S6 L6 (M=Ag or Cu) were synthesized by simple solvothermal reaction, where the cooperation of heavy atom-rich character and TADF mechanism supports strong X-ray absorption and rapid luminescent collection of excitons. Excitingly, Ag6 S6 L6 (SC-Ag) displays a high photoluminescence quantum yield of 91.6 % and scintillating light yield of 17420 photons MeV-1 , as well as a low detection limit of 208.65 nGy s-1 that is 26 times lower than the medical standard (5.5 µGy s-1 ). More importantly, a high X-ray imaging resolution of 16 lp/mm based on SC-Ag screen is demonstrated. Besides, rigid core skeleton reinforced by metallophilicity endows clusters M6 S6 L6 strong resistance to humidity and radiation. This work provides a new view for the design of efficient scintillators and opens the research door for silver clusters in scintillation application.

Polyarylisocyanides Derived from an Alkyne-Pd(II) Catalyst as Robust Alignment Media with Excellent Enantiodiscimination.

The development of chiral alignment media for measuring anisotropic NMR parameters provides an opportunity to determine the absolute configuration of chiral molecules without the need for derivatization. However, chiral alignment media with a high and robust enantiodiscriminating property for a wide range of chiral molecules are still scarce. In this study, we synthesized cholesterol-end-functionalized helical polyisocyanides from a chiral monomer using a cholesterol-based alkyne-Pd(II) initiator. These stereoregular polyisocyanides form stable and weak anisotropic lyotropic liquid crystals (LLCs) in dichloromethane systems, exhibiting highly optical activities in both single left- and right-handed helices. The preparation process of the media was straightforward, and the aligning property of the LLCs could be controlled by adjusting the concentration and temperature. Using the chiral polyisocyanides, we extracted the residual dipolar coupling for an enantiomeric pair of isopinocampheol (IPC), as well as a number of pharmaceutical molecules, demonstrating excellent enantiodiscriminating properties for a broad range of chiral compounds.

Two Noncentrosymmetric Bismuth Phosphates: Rational Design Synthesis and Optical Properties.

Developing strategies to rational design noncentrosymmetric structure still attract much interest for their applications in nonlinear optical and piezoelectric materials. Two noncentrosymmetric (NCS) alkaline earth metal bismuth phosphates have been successfully achieved via partial replacement of Bi3+ with Ca2+ or Sr2+ ions. BiCa(H0.5PO4)2 (designated as CaBiPO) and BiSr(H0.5PO4)2 (designated as SrBiPO), together with their solid solution Bi(Sr1-xCax)(H0.5PO4)2 (0 < x ≤ 0.5), crystallize in the NCS space group C2. Both CaBiPO and SrBiPO exhibit ultraviolet nonlinear optical (NLO) properties, and their second-harmonic generation effects belong to type-II phase matching. Meanwhile, they could also act as photoluminescence hosts in which the Eu3+-doping samples SrBiPO:xEu3+ (x = 0.02-0.2) emit orange light. The effect of different radius ions on the derivative structures and the structure-NLO property relationship has also been discussed in detail.

Bottom-Up Photosynthesis of an Air-Stable Radical Semiconductor Showing Photoconductivity to Full Solar Spectrum and X-Ray.

Single-component semiconductors with photoresponse to full solar spectrum are highly desirable to simplify the device structure of commercial photodetectors and to improve solar conversion or photocatalytic efficiency but remain scarce. This work reports bottom-up photosynthesis of an air-stable radical semiconductor using BiI3 and a photochromism-active benzidine derivative as a photosensitive functional motif. This semiconductor shows photoconductivity to full solar spectrum contributed by radical and non-radical forms of the benzidine derivative. It has also the potential to detect X-rays because of strong X-ray absorption coefficient. This finding opens up a new synthetic method for radical semiconductors and may find applications on extending photoresponsive ranges of perovskites, transition metal sulfides, and other materials.

Oscillation of Electronic-Band-Gap Size Induced by Crystalline Symmetry Change in Ultrathin PbTe Films.

For the semiconductors of atomic length scales, even one atom layer difference could modify crystal symmetry and lead to a significant change in electronic structure, which is essential for modern electronics. However, the experimental exploration of such effect has not been achieved due to challenges in sample fabrication and characterization with atomic-scale precision. Here, we report the discovery of crystal symmetry alternation induced band-gap oscillation in atomically thin PbTe films by scanning tunneling microscopy. As the thickness of PbTe films is reduced from an 18- to 2-atomic layer, the band-gap size not only expands from 0.19 eV to 1.06 eV by 5.6 fold, but also exhibits an even-odd-layer oscillation, which is attributed to the alternating crystal symmetries between P4/mmm and P4/nmm. Our work sheds new light on electronic structure engineering of semiconductors at atomic scale for next-generation nanoelectronics.

Nanoscale multistate resistive switching in WO3 through scanning probe induced proton evolution.

Multistate resistive switching device emerges as a promising electronic unit for energy-efficient neuromorphic computing. Electric-field induced topotactic phase transition with ionic evolution represents an important pathway for this purpose, which, however, faces significant challenges in device scaling. This work demonstrates a convenient scanning-probe-induced proton evolution within WO3, driving a reversible insulator-to-metal transition (IMT) at nanoscale. Specifically, the Pt-coated scanning probe serves as an efficient hydrogen catalysis probe, leading to a hydrogen spillover across the nano junction between the probe and sample surface. A positively biased voltage drives protons into the sample, while a negative voltage extracts protons out, giving rise to a reversible manipulation on hydrogenation-induced electron doping, accompanied by a dramatic resistive switching. The precise control of the scanning probe offers the opportunity to manipulate the local conductivity at nanoscale, which is further visualized through a printed portrait encoded by local conductivity. Notably, multistate resistive switching is successfully demonstrated via successive set and reset processes. Our work highlights the probe-induced hydrogen evolution as a new direction to engineer memristor at nanoscale.

Highly Sensitive Direct X-Ray Detector Based on Copper(II) Coordination Polymer Single Crystal with Anisotropic Charge Transport.

Anisotropic charge transport plays a pivotal role in clarifying the conductivity mechanism in direct X-ray detection to improve the detection sensitivity. However, the anisotropic photoelectric effect of semiconductive single crystal responsive to X-ray is still lacking of theoretical and experimental proof. The semiconductive coordination polymers (CPs) with designable structures, adjustable functions, and high crystallinity provide a suitable platform for exploring the anisotropic conductive mechanism. Here,the study first reveals a 1D conductive transmission path for direct X-ray detection from the perspective of structural chemistry. The semiconductive copper(II)-based CP 1 single crystal detector exhibits unique anisotropic X-ray detection performance. Along the 1D π-π stacking direction, the single crystal device (1-SC-a) shows a superior sensitivity of 2697.15 µCGyair -1  cm-2 and a low detection limit of 1.02 µGyair  s-1 among CPs-based X-ray detectors. This study provides beneficial guidance and deep insight for designing high-performance CP-based X-ray detectors.

[Application and Prospect of Nanopore Sequencing Technology in Etiological Diagnosis of Blood Stream Infection].

Blood stream infection (BSI),a blood-borne disease caused by microorganisms such as bacteria,fungi,and viruses,can lead to bacteremia,sepsis,and infectious shock,posing a serious threat to human life and health.Identifying the pathogen is central to the precise treatment of BSI.Traditional blood culture is the gold standard for pathogen identification,while it has limitations in clinical practice due to the long time consumption,production of false negative results,etc.Nanopore sequencing,as a new generation of sequencing technology,can rapidly detect pathogens,drug resistance genes,and virulence genes for the optimization of clinical treatment.This paper reviews the current status of nanopore sequencing technology in the diagnosis of BSI.

A Clinical Study of Platelet-Rich Fibrin Combined With Autologous High-Density Fat Transplantation in Augmentation Rhinoplasty.

OBJECTIVE: This study was designed to analyze the clinical effect of autologous fat-granule transplantation in augmentation rhinoplasty and explore methods to improve the fat retention rate. METHODS: A total of 70 enrolled patients were randomly divided into 2 groups: the platelet-rich fibrin (PRF) combined with high-density fat transplantation group (combined group) and the conventional fat-granule transplantation group (control group; n = 35 in each group). In the combined group, an appropriate amount of autologous fat was extracted and centrifuged, and the lower layer of high-density fat was taken and mixed with PRF isolated from whole blood for autotransplantation. In the control group, only fat was extracted and centrifuged for transplantation. The patients were followed up with for more than one year to observe the short- and long-term effects, complications, safety, and patient satisfaction. RESULTS: Six months after the operation, the nasal shape was stable, the contour was higher and more stereoscopic than before, the average increase of nasal height was 3.0 mm in the combined group and 2.0 mm in the control group. No complications, such as fat embolism, infection, or necrosis occurred during the 1-year follow-up. The satisfaction rate between the 2 groups has statistical significance (P < .05). CONCLUSION: Overall, PRF combined with autologous high-density fat transplantation is simple to perform, has a significantly increased fat-retention rate than the control group, and has stable long-term effects without obvious adverse reactions. A sufficient amount of fat and PRF transplantation can achieve a good orthopedic effect. Thus, this method can be widely used in clinical augmentation rhinoplasty.

Application and Prospect of Nanopore Sequencing Technology in Etiological Diagnosis of Blood Stream Infection / 中国医学科学院学报

Blood stream infection (BSI),a blood-borne disease caused by microorganisms such as bacteria,fungi,and viruses,can lead to bacteremia,sepsis,and infectious shock,posing a serious threat to human life and health.Identifying the pathogen is central to the precise treatment of BSI.Traditional blood culture is the gold standard for pathogen identification,while it has limitations in clinical practice due to the long time consumption,production of false negative results,etc.Nanopore sequencing,as a new generation of sequencing technology,can rapidly detect pathogens,drug resistance genes,and virulence genes for the optimization of clinical treatment.This paper reviews the current status of nanopore sequencing technology in the diagnosis of BSI.

Clinical Application of a Bird-Beak-Type Z-Shaped Asymmetrical Flap in the Reconstruction of the Inner Canthus.

Objective: To introduce a new surgical method for the repair of a large inner canthus combined with tissue loss at the inner canthal angle of the eye by using a bird-beak-type z-shaped asymmetrical flap and to summarize its clinical effect. Method: A total of 56 patients with a large inner canthus were randomly selected, and a bird-beak-type z-shaped asymmetrical flap was used on the nasal side of the lower eyelid to repair and reconstruct the inner canthal folds. The inner canthal point was located according to physiological aesthetics. The short and long arms of the z-shaped asymmetrical flap were separated, replaced, fixed, and shaped to reconstruct the skin folds of the inner canthus and restore its aesthetic morphology. Results: All incisions after surgery achieved primary healing, and all 56 cases were followed up for 6-20 months (average 8.6 months). The caruncula lacrimalis was moderately exposed, the inner canthal angles possessed a natural appearance, and the results of the surgery were satisfactory. Five patients developed scar hyperplasia within one month after surgery, and arnica gel was applied topically for 3-6 months until the scar faded or disappeared, but no obvious scars were seen in the surgical area of the remaining patients. In two patients, the internal canthi were asymmetrical, but this improved after adjustment. Conclusion: Repair of a large inner canthus and tissue loss at the inner canthal angle of the eye using a bird-beak-type z-shaped asymmetrical flap is a simple operation, resulting in minimal trauma. Postoperatively, the inner canthal angle possessed a natural appearance with no obvious scarring.

A photochromic and scintillation Eu-MOF with visual X-ray detection in bright and dark environments.

The detection of X-rays has always been a frontier of scientific research. An Eu-MOF with both X-ray-induced photochromic and scintillation properties has been synthesized through the combination of a photochromism-active viologen ligand and rare earth Eu element with high-efficiency absorption of X-rays. In a bright environment, Eu-MOF exhibits different color changes under high-energy X-rays and low-energy X-rays, which can effectively distinguish X-rays. Eu-MOF can also be used for X-ray detection by scintillation properties in dark environments. This work provides a new perspective on the design of multifunctional materials that can perform simple X-ray detection in different environments.

Determination of fluoroquinolones in chicken muscle by molecularly imprinted graphitic carbon nitride-based solid-phase extraction and ultra-performance liquid chromatography.

A graphitic carbon nitride was synthesised and nalidixic acid (NA) based molecularly imprinted microspheres (MIMs) were polymerised on its surface to create a composite material. After characterisation and evaluation of its absorption ability, the composite was used to prepare a solid-phase extraction (SPE) cartridge for purification of fluoroquinolones in chicken muscle, analysed by ultra-performance liquid chromatography. The cartridge showed high absorption capacities (378-559 µg) and high recoveries (92.1-99.4%) for eight fluoroquinolones, and could be reused at least 20 times. The limits of detection for the 8 drugs were 0.2-0.8 ng g-1, and recoveries from standard fortified blank chicken muscle samples were 71.9-96.8%. This is the first study reporting the use of molecularly imprinted graphitic carbon nitride composite to determine the residue of veterinary drug in foods of animal origin.

Analysis of force and displacement of anchor systems under the non-limit active state.

This paper proposes a concept of soil shear strength exertion around an anchorage section to analyze and calculate the anchor's force and displacement. First, based on the Mohr stress circle, the numerical relationship between the value of the internal friction angle exertion, the value of the cohesion exertion, and the displacement are established under the non-limit active state. According to the interaction mechanism between the anchorage section and the surrounding soil, this paper obtains the corresponding relationship between the value of the soil's shear strength exertion and displacement under the non-limit active state. Then, according to the load transfer principle of the anchorage section, the basic differential equation is established. The differential equation of the relative displacement distribution along the length of the anchorage section under the non-limit active state is further derived. And the calculation and analysis formula of the shear stress and relative displacement in the anchorage section considering the process of the soil shear strength exertion is also obtained. Finally, this paper compares the calculation method with the hyperbolic model calculation method for the same example. The results verify the accuracy of the calculation method.