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Purpose This study aimed to investigate the comparison and relationship between serum heat shock protein 72 (sHSP72) and intestinal permeability in patients with cerebral infarction (CI) and healthy individuals to elucidate the link to gut microbiota alterations and clinical severity of CI. Methods Stool samples of 50 CI patients and 46 healthy volunteers were applied to characterize intestinal flora profile through 16S rRNA gene sequencing. Composition difference and taxon evaluation were observed. sHSP72 and zonulin were assayed using enzyme-linked immunoassay (ELISA). Medical comorbidities and dietary habits were acquired using questionnaires and partial biochemical index were recorded. The obtained data were then subjected to comparative and correlative analysis. Results We found that the levels of zonulin and sHSP72 were significantly higher in CI group compared to the healthy group. Strikingly, sHSP72 and zonulin levels were positively correlated in CI group. After adjustment for age, gender, medical comorbidities and biochemical index, sHSP72 and zonulin levels correlated positively with clinical severity of CI. In the CI patient group, the abundance of bacteria Eubacterium_fissicatena_group, Eubacterium_eligens_group and Romboutsia manifested remarkably positive correlation with sHSP72. The abundance of bacteria Eubacterium_fissicatena_group and Acetivibrio were significantly positive correlation with zonulin levels. The CI group had a decreased abundance of Eubacterium_fissicatena_group, Eubacterium_eligens_group and Romboutsia, and an increased abundance of Acetivibrio. Conclusion Our findings represented that an increase in sHSP72 and zonulin levels were manifested in patients with CI and related to specific gut microbiota alterations and the clinical severity of CI.

BackgroundInfants with Alagille syndrome (ALGS) need to be promptly differentiated from biliary atresia (BA) at an early stage. ALGS is an autosomal, dominant, multisystem disorder with variable phenotypic penetrance caused by heterozygous mutations in JAG1 or NOTCH2, which encode the Notch signaling pathway.Case presentationWe report two cases, both with cholestatic jaundice as the main manifestation, in which BA was excluded and finally diagnosed as ALGS based on characteristic facial features, serological tests, imaging, laparoscopic cholangiography, pathology and genetic findings. Both cases are novel mutant genes on chromosome 20 that have not been reported in the literature. The mutation in patient 1 was a novel heterozygous nonsense mutation (NM_000214 exon20, c.2419G > T, p.E807Ter), which was a spontaneous mutation. Followed up to 1 year and 6 months, the symptoms resolved with ursodeoxycholic acid and cholestyramine, and the jaundice has now subsided. Patient 2 was a novel heterozygous frameshift mutation (NM_000214 exon19, c.2367–2368dupTC, p.P790Lfs*31), which was inherited from his mother. This patient was followed up to 9 months and is currently awaiting liver transplantation.ConclusionBoth cholestatic infants reported combined to exclude BA, avoid Kasai portoenterostomy (KPE), and definitively diagnose ALGS. Broadening the spectrum of JAG1 gene mutations.

The relationship between gut microbiota and brain function has been studied intensively in recent years, and gut microbiota has been linked to a couple of neurological disorders including stroke. There are multiple studies linking gut microbiota to stroke in the “microbiota-gut-brain” axis. The aryl hydrocarbon receptor (AHR) is an important mediator of acute ischemic damage and can result in subsequent neuroinflammation. AHR can affect these responses by sensing microbiota metabolites especially tryptophan metabolites and is engaged in the regulation of acute ischemic brain injury and chronic neuroinflammation after stroke. As an important regulator in the “microbiota-gut-brain” axis, AHR has the potential to be used as a new therapeutic target for ischemic stroke treatment. In this review, we discuss the research progress on AHR regarding its role in ischemic stroke and prospects to be used as a therapeutic target for ischemic stroke treatment, aiming to provide a potential direction for the development of new treatments for ischemic stroke.

Design and synthesis of platinum catalysts within atomic level are of great significance for the practical application of fuel cells. We found that the ultrathin Co(OH)2 nanoparticles can be converted into Co3O4–Co core-shell nanostructures through a thermal annealing process in reducing atmosphere, which are uniformly distributed on the surface of 3D graphene (3DG). The Co3O4–Co core-shell nanoparticles have been successfully transformed into Co3O4–Pt core-shell nanoparticles via a controlled replacement reaction. The Co3O4–Pt @3DG contains only a few atomic layers of Pt shell, and presents a high Pt utilization nanostructure. Besides, the 3D graphene serves as a catalysts carrier with open structure, and offers a three-dimensional molecular accessibility and conducive to mass transfer. Significantly, the optimized mass activity and specific activity of 1.018 A/mgPt and 2.17 mA/cm2 have been achieved on Co3O4–Pt @3DG at 0.9 V vs RHE, which are 7.6- and 8.1- times higher than those of Pt/C (0.134 A/mgPt and 0.266 mA/cm2), respectively. The high activity is mainly attributed to the ultrathin core-shell structure with an ultrahigh Pt utilization, and the interaction between the near-surface Co3O4 and the surface Pt shell with a tensile strain to surface Pt shell, and the electrons transfer from Co to Pt.

The development of highly active and stable catalysts is a critical challenge which affects the practical application of the direct methanol fuel cells. Alloying Pt with other metals is an effectiv...

A Au-doped SrTiO3 perovskite oxide catalyst (Sr0.995Au0.005TiO3−δ) has been designed and synthesized based on thermodynamic analysis and density functional theory calculations. During reduction, Au nanoparticles with an average diameter of 2 nm are in situ exsolved and evenly distributed on the surface of a SrTiO3 substrate. The as-prepared catalyst shows a high conversion of 95.0% and a high selectivity of 96.3% towards styrene epoxidation in CH3CN using H2O2 as the oxidant, and the conversion maintained at 78.2% after five cycles. Noteworthily, such performances surpass those of ex situ deposited Au nanoparticles on SrTiO3 with the same loading (88.5% initial conversion and 90.1% initial selectivity; 48.1% conversion after five cycles). The enhancement is attributed to the smaller particle size and stronger particle–substrate interaction, as revealed by XPS and TEM characterization. Mechanistic investigation confirms the strong support effect in the in situ exsolution system, where charge is transferred from SrTiO3 to Au, improving the reactivity and selectivity. The results demonstrate the unique advantages of the in situ exsolution approach, which may further be applied to develop heterogeneous catalysts with stable nanoparticles.

Atomically dispersed Fe–N–C catalysts with additional Fe-containing nanoparticles including metal, carbides or oxides have shown great potentials towards oxygen reduction reaction (ORR) catalysis. However, the formation of these synergistically active nanoparticles and the effect of the porous carbon structures remain unclear. In this work, a novel single-atom-involved electrochemical catalyst, i.e., Fe3O4 nanoparticles encapsulated in atomically dispersed Fe–N–C (Fe3O4@FeNC) was reported. The optimized Fe3O4@FeNC exhibits excellent ORR activity with a half-wave potential of 0.890 V and a Tafel slope of 58.8 mV dec−1, comparable with recently reported ORR catalysts and superior to these of commercial Pt/C. More importantly, the porous architectures not only affect the mass transfer and active sites, but casts huge influence on the nucleation of Fe3O4 nanoparticles, the graphitization degree of the carbon support, the chemical environments of the elements, and the ORR catalytic pathways. Density functional theory calculations show stronger O2 adsorption on Fe–N–C when supported on Fe3O4 moieties, which may increase the reactant concentration for ORR and promote the overall activity. These findings will provide important references for the future understanding and design of single-atom-involved catalysts with enhanced electrochemical properties.

Carbon materials have become a research hotspot in many fields because of their unique properties. In this paper, carbon nanowires (CNWs) were constructed with the finite-difference time-domain (FDTD) technique, and the effects of different structural parameters on the optical absorption properties of CNWS arrays at 350–810 nm were investigated. The results show that different lengths, diameters and spacings of the nanowires lead to different absorption properties of the arrays. In addition to a sharp decrease in the absorption at high incidence or viewing angles, the arrays have strong absorption properties at other angles. However, the array absorption at high incidence or viewing angles can be enhanced to some extent by varying the lengths of the nanowires. The wavelength and polarization direction of the excitation light have little effect on the absorption properties of the arrays. It is very important to determine the corresponding structural parameters of CNWs with the strongest absorption for the fabrication of nanowire arrays and their applications in stealth technologies, nanolight-emitting devices, photoelectric sensors and photovoltaic cells.

Committed to improving the utilization efficiency of Pt atoms and accurately controlling the morphology and composition of nanocatalysts to boost the Pt-based catalyst performance has become the focus of research. Herein, the PtRhNi truncated triangular nanoflakes (TA-NFs) catalyst with a unique PtRh-rich surface structure was successfully prepared by an effective one-pot synthetic method based on the galvanic replace reaction. The freestanding 2D nanostructure of PtRhNi TA-NFs, intrinsically possessing much high specific surface area and surface atomic, and the PtRh-rich characteristics of the surface is undoubtedly the most feasible model to simultaneously achieve high atom utilization. Benefiting from this novel structure, the as-obtained PtRhNi TA-NFs nanocatalyst exhibits excellent performance for ORR and MOR, delivering a mass activity of 0.92 A mgpt-1 for ORR, which is 2.03, 1.64, and 6.9-fold higher than that of PtRhNi nanoparticls (NPs), PtNi truncated triangle nanoflakes (TA-NFs) and commercial Pt/C, respectively. In addition, after 20 k cycles ADT test, PtRhNi TA-NFs show only 10 mV negative shift of half-wave potential and retain 70% of initial value of mass activity. Furthermore, a mass activity is 1.28 A mgpt−1 is achieved after applying this unique nanocatalyst for MOR, which is 1.28,1.5, and 2.6 times higher than that of PtRhNi NPs, PtNi TA-NFs and Pt/C, respectively. Impressively, the PtRhNi TA-NFs nanocatalyst shows an ultrahigh stability even after 2 k cycles ADT measurement in acid solution, and the mass activity is only drop 2% of initial value. This work provides a new strategy to synthesis high-performance of bifunction Pt-based electrocatalyst for ORR and MOR fuel cells.

Background: The strategies forchildren with initial unilateral inguinal hernia are open or laparoscopic herniorrhaphy. However, the clinical criteria for choosing an optimized treatment remains unclear.In this study, we aim to find a new strategy for optimizing the treatment of unilateral inguinal hernia. Methods: 1843 boys with left-sided inguinal hernia underwent open or laparoscopic herniorrhaphy were enrolled in our study and were divided into two groups: ultrasonography group (UG) and non- ultrasonography group (NUG). Spermatic cord ultrasonography was used for detecting the width of spermatic cord (WSC). Age at initial operation, WSC, operative findings, hospitalization expenses, incidence of metachronous inguinal hernia (MIH), rate of contralateral patent processes vaginalis (CPPV) and complications were recorded and analyzed. Findings: In the open herniorrhaphy group, the incidence of MIH in the WSC < 0 · 35 cm of UG was lower than NUG. The patients with left-sided WSC ≥ 0·55 cm all had been confirmed contralateral inguinal hernia. In the laparoscopic herniorrhaphy group, the rate of CPPV in UG was much higher than NUG. There was no significant difference in total incidence of complications between two groups. Interpretation: Spermatic cord ultrasonography was helpful for choosing the treatment of unilateral inguinal hernia. Following this strategy may reduce the incidence of MIH, increase the rate of CPPV of laparoscopic herniorrhaphy without any increase in complications. Funding: This work was supported by National Natural Science Foundation of China 81901989 and Project funded by China Postdoctoral Science Foundation 2019M652108 and 2018M642463. Declaration of Interests: The authors declare that they have no competing interests. Ethics Approval Statement: This retrospective study was approved by the Institutional Review Board of the Children’s Hospital, Zhejiang University School of Medicine. Patients’ guardian all gave written informed consent.

We investigate the colored noise induced resonance at the 1/3 subharmonic frequency in the overdamped and the underdamped bistable systems by numerical simulations. We find that the resonance at the 1/3 subharmonic frequency may be stronger than the traditional stochastic resonance that occurring at the excitation frequency in some cases. Moreover, we study the effects of the correlation time of the colored noises on the response in detail. If the colored noise is generated by the Ornstein–Uhlenbeck process, there are two major results discovered. Firstly, the critical noise intensity which induces the strongest resonance will increase with the increase of the correlation time. Secondly, when the noise intensity is large enough, the response amplitude at the considered frequency will also increase with the increase of the correlation time. If the colored noise is generated by the power-limited process, the corresponding results are contrary to those in the system under the colored noise excitation that is generated by the Ornstein-Uhlenbeck process. The results in this paper indicate that the type of the colored noise has important effects on the responses of the system.

Perovskite oxides have been intensively studied for electrochemical catalysis, due to their tunable composition, low cost, and strong structure-activity relationship. Here we report a novel and facile strategy to enhance the ORR activity and stability of Ba0.5Sr0.5Co0.8Fe0.2O3-δ (BSCF) perovskite oxide through engineering the surface electronic structure with ionic liquid (IL). BSCF-IL shows a boosted intrinsic activity ∼2.7 times that of BSCF, with a positively shifted half-wave potential by 40 mV and significantly improved stability. The enhancement is attributed to the strong electronic interaction between BSCF and IL, which triggers the surface amorphization and selective elemental preservation, promoting the exposure of active sites. Synchrotron-based X-ray absorption spectroscopy and density functional theory calculations reveal the charge transfer from BSCF to IL and the oxidation of surface Co and Fe, leading to the optimized eg filling, lifted O-2p band center and improved metal 3d-O 2p hybridization, contributing to higher ORR catalysis.

Lithium-sulfur batteries have great potential as the next-generation clean energy storage systems due to their remarkable high-energy density and electrochemical capacity. Additionally, sulfur is used as a cathode material because of its characteristics of a low cost, environmental friendliness, and abundant nature. However, the polysulfide shuttle effect decreases the electrochemical performance of lithium-sulfur batteries. Here, a rational membrane/electrode design has been applied to lithium-sulfur batteries. A three-dimensional hierarchical nanoporous carbon material derived from cationic resins in a cost-effective process was synthesized at a high temperature and utilized as an intermediate layer to improve the rate capability and cycle stability of lithium-sulfur batteries. Furthermore, stereotaxically -constructed multiporous graphene with a high conductivity (1.6 × 103 S m−1), porosity and large specific surface area (824 m2 g−1) has been applied in the cathode to increase the conductivity of sulfur, improve the transport of lithium-ions and increase the contact with the electrolyte. In particular, stereotaxically-constructed multiporous graphene was used as the sulfur carrier (sulfur loading 70 wt %). The electrochemical results revealed an initial discharge capacity of the hierarchical nanoporous carbon material intermediate layer-coated membrane of 1008 mAh g−1 at 0.5C, and the reversible capacity was 532 mAh g−1 at 1C after 300 cycles. Based on the experimental evidence and analyses, we concluded that the enhanced performance is due to the confinement of lithium polysulfides by the micropores and mesoporous structure of the hierarchical porous carbon material and the increased transportation of lithium ions and the improved wettability of membrane by electrolyte.

Controllable synthesis of Pt-based materials at the nanoscale can efficiently tailor their electrocatalytic performance, enabling enhancement in both activity and durability. Herein, we report the synthesis of ultrathin PtCo nanorod assemblies (NRAs) terminated with high index facets through a grain-boundary corrosion approach. Atomic insight reveals that grain boundaries and other defects are formed in PtCo nanowire assemblies (NWAs) during the hydrothermal reaction. With a further increase in reaction time, selective dissolution at these sites generated PtCo NRAs composed of shorter nanorod assemblies with larger surface areas and high index facets termination. The carbon-supported catalyst of PtCo NRAs exhibits high mass activity of 0.914 A/mgPt at 0.9 V vs RHE for ORR, 2.4 times higher than those of the smooth PtCo NWAs (0.377 A/mgPt), 5.7 times higher than those of the commercial Pt/C (0.161 A/mgPt). Most significantly, the PtCo NRAs show high stability with about 25.6% loss of mass activity after 10,000 cycles, while only 22.3% loss of mass activity from 10,000 cycles to 50,000 cycles of accelerated durability test. The high durability is mainly attributed to the jagged surface resulted from the surface reconstruction of PtCo NRAs during the electrochemical process. This self-optimization phenomenon may lead to a new effective long-life electrocatalyst.

Knowledge of the decomposition process of the microstructure during the precipitation reaction is a requisite step in many cases for exploiting their unique properties. While the earlier work demonstrated that the formation of one-dimensional (1D) Guinier–Preston–Bagaryatsky (GPB) zones is critical for the initial- and peak-hardening of the Al-Cu-Mg alloys, the essential questions remain: what are the basic structural features and the precursors of GPB zones, and how do these precursors transform to the GPB zones? Here we employ atomic-resolution scanning transmission electron microscopy (STEM) and first-principles calculations to address these problems. In mostly GPB zones-strengthened alloys, we identify two atomistic building blocks of 1D GPB zones, which merge together maintaining a crystallographic orientation of [014]Al. These two particular structures are formed from initial copper double (Cu2) column-skeleton, associated with charge transfer between adjacent Cu and Mg as well as Cu and Al inside the structural units and at the interface between two building block units. Existence of initial and transitional phases is further suggested by ab initio calculations based on STEM observations and image simulations. These results demonstrate the atomistic mechanisms governing Cu2 columns-guided nucleation, growth, maturation and coarsening of the atomistic building blocks of GPB zones. Keywords: Al alloys, Precipitation, Atomic structure, Phase transformations, Transmission electron microscopy

Foam fractionation is a cost-effective method to separate laccase from its fermentation broth. However, the enzyme readily suffered a substantial activity loss in the separation process. To reduce the activity loss, we firstly analyzed the structure-function relationship of laccase to explain how laccase was denatured in the foam fractionation of laccase from fermentation broth of Trametes hirsuta 18 using cetyltrimethyl ammonium bromide (CTAB) as a collector. The results demonstrate that via electrostatic force, CTAB interacted with laccase molecules to cause their structural unfolding, so CTAB resulted in the denaturation of laccase. Increasing the molar ratio of CTAB vs laccase at the gas-liquid interface over that in the feed solution, foaming enhanced the CTAB-induced denaturation. On this ground, we attempted to use β-cyclodextrin and ultrasound to assist the refolding of laccase denatured jointly by CTAB and foaming in the foamate. Ultrasound effectively assisted the renaturation of denatured laccase after it was separated from CTAB by β-cyclodextrin in 40 min at 20 °C or lower. Furthermore, their renaturation performances highly depended on pH, volumetric airflow rate, CTAB concentration and molar ratio of β-cyclodextrin vs CTAB in the foamate. At pH 6.0, volumetric airflow rate 60 mL/min, CTAB concentration 0.4 g/L and molar ratio of β-cyclodextrin vs CTAB in the foamate of 1.6:1, the enrichment ratio and recovery yield of laccase activity and purification fold of laccase reached 73.4%, 11.9 and 3.5, respectively. They were 230% higher than those without β-cyclodextrin and ultrasound. Therefore, ultrasound and β-cyclodextrin effectively enhanced the CTAB-assisted foam fractionation of laccase from the fermentation broth of T. hirsuta 18. In addition, a SDS-PAGE analysis determined that laccase of 55 kDa in molecular weight was highly enriched by the foam fractionation.

To evaluate the efficacy and safety of transumbilical single-site laparoscopic surgery for congenital duodenal obstruction (CDO) in neonates.A retrospective analysis of clinical data of 15 patients with CDO undergoing transumbilical single-site laparoscopic treatment during November 2017 and January 2018 (single-site group), and 20 patients with CDO undergoing conventional three-hole laparoscopic treatment during August 2017 and October 2017 (three-hole group) was performed. All patients were from the Children's Hospital, Zhejiang University School of Medicine. The operation time, time of initial feeding, time of adequate feeding, length of hospital stay after operation and postoperative complications were compared between two groups.The operations were completed in all patients. No patient converted to laparotomy, and no massive hemorrhage was observed during operation. The operation time of single-site group was (90±10) min for patients with duodenal diamond-shaped anastomosis and (81±15) min for patients with Ladd operation, while those of three-hole group were (85±9) min and (72±11) min, respectively. Postoperative initial feeding time of single-site group was (5.0±1.0) d, and that of the three-hole group was (4.8±0.8) d. The adequate feeding time was (9.0±1.2) d in the single-site group, and (9.3±0.8) d in the three-hole group. The length of hospital stay after operation was (11.2±2.5) d in the single-site group, and (11.5±2.8) d in the three-hole group. There was no significant difference in operation time, postoperative initial feeding time, adequate feeding time and length of hospital stay after operation between two groups (allTransumbilical single-site laparoscopic surgery for CDO in neonates is safe and effective, and the postoperative abdominal scar is more hidden.

The Donggua Mountain strata-bound skarn copper deposit located in the Tongling region of Anhui Province (China) is concealed in Carboniferous bedded skarns. The depth of upper boundary of the ore body is about 800 m from the surface. The primary geochemical characteristics of the mineral deposit were studied based on assay data for 52 composite samples from the surface outcrops and 308 core samples from the drill holes. The results show that the distributional patterns of concentrations of Cu, Ag, Mo, Te, W, Pb, Bi, As, I, U and Sr in the surface are well corresponded with the deep ore body. The formation of the primary geochemical haloes, which joined the ore body to the surface, can be associated with hydrothermal fluid diffusion through fracture (fissures) zone developed in the rocks of the fold axis in the mining area. In the vertical direction, the contents for Cu, Ag and Te have an increasing trend from the surface to the ore body on the whole, while the contents for As and Pb are decreased with depth on the whole. The As/Te ratio keeps a decreasing trend from the surface to the ore body, whereas the Cu/As ratio from the surface to the ore body increases with depth on the whole. These findings may have implications for the detection of similar skarn-type mineral deposits.