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Not all stents are suitable for children. For instance, premounted stents can be used in infants and small children but cannot dilate with age to accommodate adult-sized pulmonary arteries. Conversely, the Pul-Stent adapts to somatic growth. Thus, our hospital implemented the Pul-Stent in pediatric patients with branch pulmonary artery stenosis. This study summarizes our initial experience with Pul-Stents in this patient population, including the efficacy and safety. We implanted 37 Pul-Stents in 35 patients between August 2014 and June 2015. The patients’ mean age and weight at stent implantation were 6.7 ± 3.0 years and 20.9 ± 8.7 kg, respectively. Bench testing revealed that axial shortening of the Pul-Stent was minimal with further dilation, and the radial strength did not change. The stents were successfully deployed in all cases, except two with minor malpositioning. Primarily, 8–12 mm mounting balloons were used for the initial implantation, and a long sheath (8–10 F) was used for delivery. After stent implantation, the minimal lumen diameter in the stenosed segment increased by 50% in 97% (34/35) of patients. Furthermore, the pressure gradient across the stenosed segment decreased by 50% in 77% (23/30) of biventricular patients. One stent fracture and one stent restenosis were noted during the follow-up visits (mean follow-up time: 4.6 ± 1.7 years). Eighteen patients (51%) underwent repeat catheterization; ten had successful redilation. No aneurysms or stent fractures were observed. Our initial results indicate that the Pul-Stent is safe and effective in pediatric patients and can be further dilated over time to accommodate somatic growth. Moreover, the Pul-Stent has good compliance and adequate radial strength to treat pulmonary artery stenosis effectively.

Bisborylalkanes play important roles in organic synthesis as versatile bifunctional reagents. The two boron moieties in these compounds can be selectively converted into other functional groups through cross-coupling, oxidation or radical reactions. Thus, the development of efficient methods for synthesizing bisborylalkanes is highly demanded. Herein we report a new strategy to access bisborylalkanes through the reaction of N-trisylhydrazones with diboronate, in which the bis(boryl) methane is transformed into 1,2-bis(boronates) via formal carbene insertion. Since the N-trisylhydrazones can be readily derived from the corresponding aldehydes, this strategy represents a practical synthesis of 1,2-diboronates with broad substrate scope. Mechanistic studies reveal an unusual neighboring group effect of 1,1-bis(boronates), which accounts for the observed regioselectivity when unsymmetric 1,1-diboronates are applied.

Twin engineering is an efficient strategy to improve the photocatalytic activity of semiconductors (e.g., BiVO4). A systematic study that combines theory and experiments is conducted to reveal the underlying enhanced catalytic mechanism of twin-structured BiVO4. The key characteristic of twinned structures is the partial strain introduced by twin boundaries. Lattice distortion introduced by the twin boundaries leads to charge redistribution and built-in electronic fields between the twin boundaries and the bulk. The generated homojunctions possess a staggered band alignment structure, and their band offsets are increased by the Fermi-level pinning effect. The series of homojunctions in twinned structures is beneficial for facilitating charge separation. Additionally, lattice distortion around twin boundaries leads to the broken geometric symmetry of metal-oxygen polyhedrons in twinned crystals. The adsorption energies of adsorbates decrease significantly, resulting in reduction of the overpotential. The reduced overpotential favors acceleration of the oxygen evolution reaction on twinned structures.

Spiro[azetidine-indolines] are important scaffolds in diverse bioactive compounds. Current efforts to synthesize spiro[azetidine-indolines] are limited to chiral spiro[azetidine-2,3'-indolines]. Asymmetric synthesis of structurally similar chiral spiro[azetidine-3,3'-indolines] remains unexplored. In this work, the first copper(I)-catalyzed asymmetric Kinugasa/aryl C-C coupling cascade reaction is described. This provides a straightforward access to densely functionalized chiral spiro[azetidine-3,3'-indoline]-2,2'-diones in good yields and with high enantioselectivity.

Gonococcal meningitis is an exceedingly rare infectious disease, and if not diagnosed and treated in time, it can be severe. We present a case of gonococcal meningitis occurring in a 31-year old healthy woman. She was admitted with fever and persistent headache without urogenital symptoms. Blood cultures were positive and identified as N.gonorrhoeae, but CSF and cervical secretions cultures were both negative. Further testing confirmed the presence of N.gonorrhoeae by 16S ribosomal gene amplification and sequencing in all samples. These results suggest that the case may be a disseminated infection caused by untreated gonorrhea. Our case also shows that nucleic acid detection plays an important role in the rapid and precise diagnosis of gonococcal meningitis and in finding the origin of the pathogen.

In this article, we investigate the dependence of nuclear temperature on emitting source neutron-proton ( ) asymmetry with light charged particles (LCPs) and intermediate mass fragments (IMFs) generated from intermediate-velocity sources in thirteen reaction systems with different asymmetries, on , and , on , , , and at 40 MeV/nucleon. The apparent temperature values of LCPs and IMFs from different systems are deduced from the measured yields using two helium-related and eight carbon-related double isotope ratio thermometers, respectively. Then, the sequential decay effect on the experimental apparent temperature deduction with the double isotope ratio thermometers is quantitatively corrected explicitly with the aid of the quantum statistical model. The present treatment is an improvement compared to our previous studies in which an indirect method was adopted to qualitatively consider the sequential decay effect. A negligible asymmetry dependence of the real temperature after the correction is quantitatively addressed in heavy-ion reactions at the present intermediate energy, where a change of 0.1 units in source asymmetry corresponds to an absolute change in temperature of an order of 0.03 to 0.29 MeV on average for LCPs and IMFs. This conclusion is in close agreement with that inferred qualitatively via the indirect method in our previous studies.

Background We aimed to assess the efficacy of different initial intravenous immunoglobulin (IVIG) regimens in Kawasaki disease (KD) patients to find more cost‐effective therapy options. Methods A multicenter, open‐label, blind‐endpoint randomized controlled trial was conducted from January 2014 to December 2015. Patients with KD, within 10 days of illness, were randomly assigned to receive different IVIG regimens (Group A, 2 g/kg once; Group B, 1 g/kg for 2 consecutive days; Group C, 1 g/kg once) and aspirin 30mg/kg/d. Primary outcomes included hours to defervescence and development of coronary artery lesions during the study period. Major secondary outcomes included total fever days, total dose of IVIG, changes of laboratory data, length of stay, and hospitalization expenses. (ClinicalTrials.gov: NCT02439996). Results A total of 404 patients underwent randomization. No difference was found in the outcomes of defervescence among three groups at 6, 12, 24, and 36 hours after completion of initial IVIG infusion. There were no differences in the incidence of coronary artery lesions during the study period (at week 2, month 1, month 3, and month 6 of illness), changes of laboratory data, total fever days, and length of stay. Group C patients had the lowest total dose of IVIG (mean: 1.2 vs 2.2 vs 2.1 g/kg; P < 0.001) and hospitalization expenses (mean: 8443.8 vs 10798.4 vs 11011.4 Chinese Yuan; P < 0.001) than other two groups. Conclusions A single dose of 1g/kg IVIG is a low‐cost treatment with the same efficacy as 2 g/kg IVIG and can be an option for the initial therapy of KD patients.

The development of efficient and stable electrocatalysts with earth-abundant elements for both oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) in the same electrolyte is incontrovertibly vital in water electrolysis. However, their large-scale fabrication remains a great challenge. Here, we report a self-supported electrocatalyst in the form of Fe-doped Ni3S2 nanoparticles in-situ grown on three-dimensional (3D) conductive Fe−Ni alloy foam (Fe−Ni3S2/AF) by surface-assisted chemical vapor transport (SACVT) method. Homogeneous growth environment and scalability of SACVT method allow Fe−Ni3S2 nanoparticles uniformly growing on AF in large-scale. Fe−Ni3S2/AF exhibits high activity and durability when act as HER catalyst and OER precatalyst in alkaline media. The HER and OER overpotential at 10 mA/cm2 is considerably small, only 75 and 267 mV, respectively. Moreover, the electrolyzer assembled by Fe−Ni3S2/AF for overall water splitting exhibits a low cell voltage and high durability in long-term test. Based on experiments and theoretical calculation, the significantly enhanced activity could be originated from the incorporation of Fe, which contributed to increase the electrochemical active surface area, enhance electrical conductivity, optimize the hydrogen and H2O adsorption energy of Ni3S2 (101) surface in HER, and form active bimetallic Ni−Fe(oxy)hydroxide in OER. The excellent durability of self-supported Fe−Ni3S2/AF could be benefited from the in-situ growth of Fe−Ni3S2 nanoparticles on 3D AF, which could ensure closely mechanical adhesion between active materials and substrate, promote charge transport and increase surface area. This work provides a facile method for large-scale synthesis of electrocatalysts with high activity and long-term durability for efficient water electrolysis in alkaline media.

Increasing evidence has highlighted the endogenous production of formaldehyde (FA) in a variety of fundamental biological processes and its involvement in many disease conditions ranging from cancer to neurodegeneration. To examine the physiological and pathological relevance and functions of FA, fluorescent probes for FA imaging in live biological samples are of great significance. Herein we report a systematic investigation of 2-aza-Cope reactions between homoallylamines and FA for identification of a highly efficient 2-aza-Cope reaction moiety and development of fluorescent probes for imaging FA in living systems. By screening a set of N-substituted homoallylamines and comparing them to previously reported homoallylamine structures for reaction with FA, we found that N-p-methoxybenzyl homoallylamine exhibited an optimal 2-aza-Cope reactivity to FA. Theoretical calculations were then performed to demonstrate that the N-substituent on homoallylamine greatly affects the condensation with FA, which is more likely the rate-determining step. Moreover, the newly identified optimal N-p-methoxybenzyl homoallylamine moiety with a self-immolative β-elimination linker was generally utilized to construct a series of fluorescent probes with varying excitation/emission wavelengths for sensitive and selective detection of FA in aqueous solutions and live cells. Among these probes, the near-infrared probe FFP706 has been well demonstrated to enable direct fluorescence visualization of steady-state endogenous FA in live mouse brain tissues and elevated FA levels in a mouse model of breast cancer. This study provides the optimal aza-Cope reaction moiety for FA probe development and new chemical tools for fluorescence imaging and biological investigation of FA in living systems.

Traditional ionic liquids are sensitive to humidity but with long response time and nonlinear response. Pure liquid-state ionic liquids are usually hard for dehydration which have ultralong response time for humidity sensing. The immobilization of ionic liquids provide a possible way for high performance humidity sensing. Hydrophobic materials and structures also promised faster response in humidity sensing, because of easier desorption of water. In this work, we prepared flexible humidity sensitive composites based on hydrophobic ionic liquid and polymer. The combination of hydrophobic ionic liquid with hydrophobic polymer realized linear response, high sensitivity with low hysteresis to humidity. By adjusting the ratio of ionic liquid, not only the impedance but also the hydrophobicity of composite could be modulated, which had a significant influence on the humidity sensing performance. The morphology and microstructure of the material also affected its interaction with water molecules. Due to the diverse processing methods of polymer, highly transparent film fabricated by spinning-coating and nanofibrous membrane fabricated by electrospinning could be prepared and exhibited different response time, which could be used for different application scenarios. Especially, the fibrous membrane made with electrospinning method showed an ultrafast response and could distinguish up to 120 Hz humidity change, due to its fibrous structure with high specific surface area. The humidity sensors with ultrafast, linear response and high sensitivity showed potential applications in human respiratory monitoring and flexible non-contact switch. To better show the multifunction of ionic liquid-polymer composite, as a proof of concept, we fabricated an integrated humidity sensitive color change device by utilizing lower ionic liquid content composite for sensing in the humidity sensing module and higher ionic liquid content composite as the electrolyte in the electrochromic module.

An enantioselective insertion of a carbene into the Csp

Bilayer graphene (BLG) shows great application prospect and potential in next-generation electronics because of its unique electrical and mechanical properties. However, the scalable synthesis of large-area high-quality BLG films is still a great challenge, despite the maturity of chemical vapor deposition (CVD) technique. In this study, we report a robust method to grow BLGs on flat, softened Cu foils by atmospheric pressure CVD. A moderate amount of residual oxygen accelerates the growth of BLG domains while suppressing the formation of multilayers. Raising the nucleation density at low hydrogen pressure efficiently increases the film continuity. Based on the optimized CVD process, the growth of graphene films on 4×4 cm2 Cu foils with an average BLG coverage of 76% is achieved. The morphology and structure characterizations demonstrate a high quality of the BLG. Dual gate field-effect transistors are investigated based on AB-stacked BLG, with a tunable bandgap and high carrier mobility of up to 6790 cm2 V−1 s−1 at room temperature.

Silver (Ag)-based materials have shown great application potential in the oxygen reduction reaction (ORR) and hydrogen peroxide (H2O2) detection. The porous structures of Ag have attracted a lot of research interest due to their large specific surface area and high electrochemical activity. In this work, nanoporous Ag structures composed of nano-sized particles were prepared by a one-step pulsed laser deposition (PLD) under controlled background gas pressure. The porous PLD-Ag showed a high ORR performance (Eonset: 1.007 V vs. RHE, E1/2: 0.863 V vs. RHE), high sensitivity (613.1 μA cm-2 mM-1 at -0.2 V vs. SCE) and selectivity for H2O2 detection. The PLD technique provided a new, yet universal approach to producing high-performance, metal-based electrochemical electrodes.

Commercial-scale photoelectrochemical (PEC) water splitting devices have been proved to be cost-competitive with fossil-based fuels. Nevertheless, large-scale PEC water splitting cells with high performance have not yet been demonstrated, and controllably scaling up high-performance photoelectrodes still remains challenging. Typically, bismuth vanadate (BiVO4) has been regarded as one of the most efficient photoanodes for use in PEC water splitting because of its well-suited band structure. However, state-of-the-art PEC performances achieved with BiVO4 photoanodes to date have generally been tested on small scales (

The straightforward strategy of building a chiral C-O bond directly on a general carbon radical center is challenging and stereocontrol of the reactions of open-chain hydrocarbon radicals remains a largely unsolved problem. Advance in this elementary step will spur the development of asymmetric radical C-O bond construction. Herein, we report a copper-catalyzed regioselective and enantioselective carboesterification of substituted dienes using alkyl diacyl peroxides as the source of both the carbon and oxygen substituents. The participation of external acids in this reaction substantially extends its applicability and leads to structurally diverse allylic ester products. This work represents the advance in the key elementary reaction of intermolecular enantioselective construction of C-O bond on open-chain hydrocarbon radicals and may lead to the discovery of other asymmetric radical reactions., Stereocontrol of C–O bond formation from a carbon-based radical is very difficult due to the rapid inversion of the carbon radical. Here the authors present a method to form chiral esters from conjugated dienes with copper and chiral PyBox ligands, likely proceeding via an allylic radical.

Twin engineering is an efficient strategy to improve the photocatalytic activity of semiconductors (e.g., BiVO

Cardiovascular disease is a leading cause of death and disability worldwide. Although genetically modified mouse models offer great potential for robust research in vivo, in vitro studies using isolated cardiomyocytes also provide an important approach for investigating the mechanisms underlying cardiovascular disease pathogenesis and drug actions. Currently, isolation of mouse adult cardiomyocytes often relies on aortic retrograde intubation under a stereoscopic microscope, which poses considerable technical barriers and requires extensive training. Although a simplified, Langendorff‐free method has been used to isolate viable cardiomyocytes from the adult mouse heart, the system requires enzymatic digestions and continuous manual technical operation. This study established an optimized approach that allows isolation of adult mouse cardiomyocytes and epicardial activation mapping of mouse hearts using a Langendorff device. We used retrograde puncture through the abdominal aorta in vivo and enzymatic digestion on the Langendorff perfusion device to isolate adult mouse cardiomyocytes without using a microscope. The yields of isolated cardiomyocytes were amenable to patch clamp techniques. Furthermore, this approach allowed epicardial activation mapping. We used a novel, simplified method to isolate viable cardiomyocytes from adult mouse hearts and to map epicardial activation. This novel approach could be beneficial in more extensive research in the cardiac field.

Increasing evidence has highlighted the endogenous production of formaldehyde (FA) in a variety of fundamental biological processes and its involvement in many disease conditions ranging from cancer to neurodegeneration. To examine the physiological and pathological relevance and functions of FA, fluorescent probes for FA imaging in live biological samples are of great significance. Herein we report a systematic investigation of 2-aza-Cope reactions between homoallylamines and FA for identification of a highly efficient 2-aza-Cope reaction moiety and development of fluorescent probes for imaging FA in living systems. By screening a set of N-substituted homoallylamines and comparing them to previously reported homoallylamine structures for reaction with FA, we found that N-p-methoxybenzyl homoallylamine exhibited an optimal 2-aza-Cope reactivity to FA. Theoretical calculations were then performed to demonstrate that the N-substituent on homoallylamine greatly affects the condensation with FA, which is more likely the rate-determining step. Moreover, the newly identified optimal N-p-methoxybenzyl homoallylamine moiety with a self-immolative β-elimination linker was generally utilized to construct a series of fluorescent probes with varying excitation/emission wavelengths for sensitive and selective detection of FA in aqueous solutions and live cells. Among these probes, the near-infrared probe FFP706 has been well demonstrated to enable direct fluorescence visualization of steady-state endogenous FA in live mouse brain tissues and elevated FA levels in a mouse model of breast cancer. This study provides the optimal aza-Cope reaction moiety for FA probe development and new chemical tools for fluorescence imaging and biological investigation of FA in living systems., Systematic investigation of various homoallylamines reveals N-p-methoxybenzyl homoallylamine as the optimal 2-aza-Cope reaction moiety for development of highly efficient formaldehyde fluorescent probes for in vitro and in vivo imaging.

Summary Polarity-reversal catalysts enable otherwise sluggish or completely ineffective reactions which are characterized by unfavorable polar effects between radicals and substrates. We herein disclose that when irradiated by visible light, bromine can behave as a polarity-reversal catalyst. Hydroacylation of vinyl arenes, a three-component cascade transformation and deuteration of aldehydes were each achieved in a metal-free manner without initiators by using inexpensive N-bromosuccinimide as the precatalyst. Light is essential to generate and maintain the active bromine radical during the reaction process. Another key to success is that HBr can behave as an effective hydrogen donor to turn over the catalytic cycles., Graphical abstract, Highlights • Using bromine as a polarity-reversal catalyst to generate acyl radicals • Additive- and metal-free, atom- and step-economic, and operationally simple process • Using constant light-irradiation to induce and maintain bromine radicals • Access carbonyl compounds and deuterated aldehydes with wide substrate scope, Chemistry; Organic chemistry; Green chemistry

Narrowing the bandgap of lead-free double-perovskite Cs2AgBiBr6 is required for using this material in future photovoltaics. Herein, we demonstrate a bandgap engineering of Cs2AgBiBr6 by introducing Sb to substitute up to 75% of Bi via a versatile solution-processed method in dimethyl sulfoxide at 180 °C. The resultant Cs2AgSbxBi1−xBr6 (x = 0, 0.25, 0.50, 0.75) thin films possess high crystallinity and good thermostability. Moreover, the Sb substitution enables an obvious bandgap reduction of 0.25 eV. The fabricated solar cell using the Cs2AgSbxBi1−xBr6 (x = 0.25) thin film obtained an increased performance than the reference Cs2AgBiBr6. The effective bandgap narrowing via a facile solution method might accelerate the development of Cs2AgBiBr6-based materials for photovoltaic applications.

Strong non-covalent cation-π interactions were discovered about three decades ago. However, the application of such interfacial behavior on carbon nanomaterials has been investigated only in recent years. In particular, with the increasing interests in graphene, efforts have been made to promote the energy generation through macroscopically shifts of the liquid/solid boundary over the carbon surface, yet the effective ways to avoid the physical wearing caused by the macroscopically shifts still lack. In the present work, a high-efficiency humidity driven electric nanogenerator based on the interfacial cation-π interaction was reported. The generator was prepared using the wrinkled graphene with intentionally increased defects and uniformly distributed wrinkles for ultrafast water evaporation, preventing excessive water accumulation and deposition of well-distributed salt crystals. Electricity was generated by manipulating the formation of ionic liquid microdroplets on the graphene surface via water adsorption and desorption of salt crystals as the humidity varied. Our work provided a new strategy for the application of strong cation−π interactions, such as energy generation, gas sensing and biointerface for cell stimulation, with readily achievable stimuli, high stability, comparable efficiency and long lifetime.

Graphene oxide (GO) has shown enormous potential in applications for improving crop yield and soil cultivation quality. However, in heavy metal contaminated soil, the effect of GO on heavy metals and the indirect toxicity of GO to plants remain unclear. In this work, we reveal the GO-promoted cadmium (Cd) uptake by rice in a Cd-contaminated soil system. The oxygen-rich functional groups and the large specific surface area of monolayer GO result in strong Cd(II) adsorption (with a maximum adsorption capacity of 265.8 mg/g), which significantly change the existing forms of Cd(II) in the soil. In particular, GO converts the inorganic-bound form Cd(II) that is not readily absorbed by plants into the exchangeable form that is more available for plant absorption. As a result, Cd(II) content in rice seedlings is increased by 12.5% with the application of GO. Therefore, it can be concluded that GO exhibited indirect toxicity to plants in heavy metal-enriched soil.

Circular RNAs (circRNAs) have been revealed as being abundantly expressed in a variety of tissues and have been found to contribute to the regulation of many autoimmune diseases. Although previous studies demonstrated that the pathogenesis of Hashimoto's thyroiditis (HT) is related with epigenetic dysregulation, the exact mechanism remains unclear. The important role of thyroid-specific circRNAs in HT attracted much attention but without any report revealed their expression profile and function in plasma of HT. In this study, the circRNA expression profile in plasma of HT was explored for the first time by using Arraystar CircRNA Microarray technology. We obtained 22 differentially expressed circRNAs (fold change ≥ 2.0 or ≤ - 2.0, p 0.05) in plasma of HT, including 7 upregulated circRNAs and 15 downregulated circRNAs. By constructing circRNA-miRNA-mRNA competing endogenous RNA (ceRNA) network, we found that upregulated circRNAs may function as ceRNAs and affect the occurrence or development of HT through chemokine signaling pathway (p 0.0001), HIF-1 signaling pathway (p = 0.02), and FoxO signaling pathway (p = 0.04). Notably, hsa_circ_0008193 verified by RT-qPCR were the major upregulation circRNAs involved in the chemokine signaling pathway. These results provide a comprehensive circRNA resource for further in-depth study of the regulatory mechanisms of circRNA in HT and may provide new insight into HT.

Polarity-reversal catalysts enable otherwise sluggish or completely ineffective reactions which are characterized by unfavorable polar effects between radicals and substrates. We herein disclose for the first time that when irradiated by visible light, bromine can behave as a polarity-reversal catalyst. Hydroacylation of vinyl arenes, a three-component cascade transformation and deuteration of aldehydes were each achieved in a metal-free manner without initiators by using N-bromosuccinimide as the precatalyst. Light is essential to generate and maintain the active bromine radical during the reaction process. Another key to success is that HBr can behave as an effective hydrogen-donor to turn over the catalytic cycles.