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ABSTRACTThis paper aims to analyse the static and dynamic characteristics of the sandwich structure consisted of an upper ballastless track structure layer, middle graded crushed stone interlayer, and lower foamed concrete subgrade layer, and clarifies its long-term dynamic stability. A full-scale test model of the sandwich structure being optimized was established, and then the static and dynamic loading tests were carried out. The results show that the use of foamed concrete as the subgrade filler can make the sandwich structure subgrade have better static stress and vibration diffusion effect compared with the traditional ballastless track subgrade. Under the loading conditions of this model test, the sandwich structure does not produce a resonance phenomenon when the loading frequency increases from 1 Hz to 10 Hz. And the sandwich structure has good vibration characteristics and long-term dynamic stability under cyclic loading. All these indicate that the graded crushed stone sandwich structure of the ballastless track foamed concrete subgrade can provide a smooth and long-term stable foundation for the line.

ABSTRACTThe subgrade-frame culvert transition section of a railway has been designed as an inverse trapezoidal shaped and filled with foamed concrete. Monitoring tests have been carried out to explore the performance of this structure, including long-term base settlement and base stress monitoring and dynamic response parameters monitoring. Based on the testing data, the distribution laws of the base stress and base settlement along the longitude direction of the transition section subgrade have been obtained. Distributions of the acceleration, dynamic displacement, and dynamic stress along the subgrade depth and along the longitude direction of the subgrade have been analysed respectively, and the attenuation coefficients of these three kinds of dynamic response parameters have been calculated. Also the relationship between the thickness of the foamed concrete layer and the dynamic response parameters has been explored. These demonstrated that the foamed concrete can improve the dynamic performance of the structure.

Herein, a simple and efficient inorganic particle surface modification strategy was developed to improve the flame retardancy of flammable polyurethane (PU) materials while avoiding the serious degradation of their mechanical properties due to the incorporation of inorganic particles. Novel organic–inorganic hybrid hydroxylation ammonium polyphosphate (OHAPP) was fabricated via an ion-exchange reaction between APP and diethanolamine, and a PU/OHAPP film was prepared by crosslinking OHAPP with reactive PU via in situ polymerization. The curing properties, flame retardancy, and mechanical properties of materials were evaluated. Results showed that the addition of 15 wt% OHAPP in PU increased the tensile strength of the sample by 16% compared to PU alone. The peak heat release rate, total heat released, and total smoke produced from the materials measured via the conical calorimetric method were 337.2 kW/m2, 78.1 MJ/m2, and 8.9 m2, respectively, which were 63.8%, 43.6%, and 15.2% lower than those of PU. Additionally, the flame-retardant mode of action of the PU/OHAPP film was verified. This study is a useful reference for further studies on flame-retardant materials.

To investigate the dynamic characteristics and long-term dynamic stability of the new subgrade structure of medium–low-speed (MLS) maglevs, cyclic vibration tests were performed under natural and rainfall conditions, and the dynamic response of the subgrade structure was monitored. The dynamic response attenuation characteristics along the depth direction of the subgrade were compared, and the distribution characteristics of the dynamic stress on the surface of the subgrade along the longitudinal direction of the line were analyzed. The critical dynamic stress and cumulative deformation were used as indicators to evaluate the long-term dynamic stability of the subgrade. Results show that water has a certain effect on the dynamic characteristics of the subgrade, and the dynamic stress and acceleration increase with the water content. With the dowel steel structure set between the rail-bearing beams, stress concentration at the end of the loaded beam can be prevented, and the diffusion distance of the dynamic stress along the longitudinal direction increases. The dynamic stress measured in the subgrade bed range is less than 1/5 of the critical dynamic stress. The postconstruction settlement of the subgrade after similarity ratio conversion is 3.94 mm and 7.72 mm under natural and rainfall conditions, respectively, and both values are less than the 30 mm limit, indicating that the MLS maglev subgrade structure has good long-term dynamic stability.

Early control of elevated blood pressure is the most promising treatment for acute intracerebral haemorrhage. We aimed to establish whether implementing a goal-directed care bundle incorporating protocols for early intensive blood pressure lowering and management algorithms for hyperglycaemia, pyrexia, and abnormal anticoagulation, implemented in a hospital setting, could improve outcomes for patients with acute spontaneous intracerebral haemorrhage.

Carbon neutrality has been proposed as a solution for the current severe energy and climate crisis caused by the overuse of fossil fuels, and machine learning (ML) has exhibited excellent performance in accelerating related research owing to its powerful capacity for big data processing. This review presents a detailed overview of ML accelerated carbon neutrality research with a focus on energy management, screening of novel energy materials, and ML interatomic potentials (MLIPs), with illustrations of two selected MLIP algorithms: moment tensor potential (MTP) and neural equivariant interatomic potential (NequIP). We conclude by outlining the important role of ML in accelerating the achievement of carbon neutrality from global-scale energy management, unprecedented screening of advanced energy materials in massive chemical space, to the revolution of atomic-scale simulations of MLIPs, which has the bright prospect of applications.

Mud pumping in subgrade beds under ballastless tracks will deteriorate the dynamic performance of infrastructure under railway lines, reduce the smoothness of the railway lines, and seriously affect the comfort and safety of the trains. Due to their good mechanical properties, two-component polyurethane materials can be used for grouting to treat the fouling problems caused by ballastless track mud pumping. To develop a polyurethane formula suitable for the treatment of ballastless track mud pumping, we first performed indoor experiments to investigate the mechanical properties and gelation time of polyurethane elastomers synthesized with different raw material composition ratios, to determine an optimal composition ratio of the raw materials. Then, we conducted a dynamic field test to verify the remediation effect of the polyurethane material fabricated according to the design ratio. The results showed that polyurethane grouting material with the selected design ratios improved the contact characteristics between the surface layer of the subgrade bed and the base plate in the area, coordinating the dynamic response between the track structure and the subgrade bed. Thus, the obtained polyurethane grouting material could be used to renovate mud pumping areas of ballastless tracks with a good treatment effect.

Objective We compared outcomes and adverse events of thrombectomy versus medical management in acute ischemic stroke (AIS) patients with baseline large infarct core.Methods We searched Ovid MEDLINE(R) ALL, Cochrane Library Clinical Controlled Trials and EMBASE from inception to January 2021 for studies comparing thrombectomy and medical management alone in AIS patients who had ASPECTS <=7 or ischemic core volume >=50 ml. Imaging modalities to valuate ASPECTS and core volume were without restriction. The functional outcome was measured by mRS (modified Rankin Scale) score 0-2 at 90 days or discharge. The safety end point included the rates of mortality and sICH (symptomatic intracranial hemorrhage) or PH2 (parenchymal hematoma type 2).Results Fourteen studies with a total of 2547 patients (thrombectomy n = [1197]; medical care alone [n = 1350]) fulfilled our criteria. As for patients with low ASPECTS, pooled results indicated a higher odds of good functional outcome (OR = 3.47; 95% CI 1.99 to 6.07; P < 0.0001, I2=66%) and a lower risk of mortality (OR = 0.62; 95% CI 0.46 to 0.83; P = 0.001, I2=32%) in thrombectomy group compared with no thrombectomy group, but the risk of sICH or PH2 did not differ between two groups. As for patients with large core volume, both functional outcome and safety end point between two groups showed no statistically significant difference.Conclusion Thrombectomy remained safe and effective by careful selection in patients with low ASPECTS. More studies were warranted to explore contraindications for mechanical thrombectomy in AIS patients, especially in patients with large core volume.

Ceria (CeO2) on Pt(111) has been widely studied in model catalysis due to the strong interfacial interaction between CeO2and platinum (Pt). Although extensive studies have been conducted on monolayered CeO2islands on the Pt(111) surface, the atomic and electronic structures of the island edge are still elusive. Herein, density functional theory calculations are employed to simulate the CeO2(111) surface, the CeO2monolayer on Pt(111), and their edges. It is found that unlike the outmost O–Ce–O layer of CeO2(111), the CeO2layer on Pt(111) is negatively charged and has non-zero magnetic moments. For the CeO2(111) surface, the stoichiometric-type edge is the most stable, and the atomic orders of two edges from outside in are Os2––Ce4+–Oi2–and Oi2––Ce4+–Os2–. For the CeO2/Pt(111) surface, however, only at high temperature and under ultra-high vacuum conditions, the most stable edge is the same as that of CeO2(111). Otherwise, an oxygen-rich edge will be formed, where the atomic orders of two edges from outside in are Oi2––Os2––Ce4+and Oi2––Ce4+–Os2–. Furthermore, the adsorption energy of the K ion on the Oi2––Os2––Ce4+-type edge is lower than that on the Oi2––Ce4+–Os2–-type edge, indicating a stronger adsorbability of the Oi2––Os2––Ce4+-type edge toward positively-charged ions. The edge structures proposed here and the corresponding electronic properties provide an insight into the interaction between CeO2and the Pt surface, which helps to understand the catalytic mechanism on the CeO2/Pt(111) surface.

Ceria supported on platinum substrate is one of the most extensively studied inverse model catalysts. Unraveling the atomic structure of the ceria film is of great importance in helping understand the performance of ceria-involving heterogeneous catalysis. In this study, scanning tunneling microscopy (STM), apparent local work function (LWF) measurement, and density functional theory (DFT) calculations are employed to explore the atomic structures of the ceria islands and their electronic interaction with the Pt(111) substrate. High-resolution STM images and DFT calculations have unraveled the atomic structures of the prepared 3:4 coincidence cells and the island step edges on Pt(111). In specific, the structural difference between the two triangular half units is unprecedentedly achieved on the atomic level. The charge transfer between the ceria island and Pt(111) dependent on the interfacial structure has also been uncovered by apparent LWF measurements.

Among the multitudinous methodologies to steer on-surface reactions, less attention has been paid to the effect of externally introduced halogen atoms. Herein, highly selective trans-dehydrogenation coupling at the specific meta-C–H site of two poly(p-phenylene) molecules, p-quaterphenyl (Ph4) and p-quinquephenyl (Ph5), is achieved on Cu(111) by externally introduced bromine atoms. Scanning tunneling microscopy/spectroscopy experiments reveal that the formed molecular assembly structure at a stoichiometric ratio of 4:1 for Br to Ph4or 5:1 for Br to Ph5can efficiently promote the reactive collision probability to trigger the trans-coupling reaction at the meta-C–H site between two neighboring Ph4or Ph5molecules, leading to an increase in the coupling selectivity. Such Br atoms can also affect the electronic structure and adsorption stability of the reacting molecules. It is conceptually demonstrated that externally introduced halogen atoms, which can provide an adjustable halogen-to-precursor stoichiometry, can be employed to efficiently steer on-surface reactions.

Transparent conductive films (TCFs) are highly desirable for making full use of solar energy. However, the production and application of TCFs are seriously restricted by two obvious weaknesses: complex processes and poor properties. In this research, simple and direct approaches including condensation reflux and hot-pressing are selected to gain a cheap TCF with good properties. The polyvinyl butyral enhanced by 6 spray layers of Ag nanowires (AgNWs/PVB) TCF is found to achieve an optical transmittance of 80.1% and a sheet resistance of 86.4 Ω/sq, and meanwhile, withstand bending cycles over 150 and an extensile rate of 15%. Additionally, the AgNWs/PVB TCF has a deep potential to be further improved by hot-pressing treatment and its sheet resistance can be reduced to 19.7 Ω/sq. Our findings may show a facile way to produce low-cost and high-performance TCFs.

Ceramic dielectrics are reported with superior energy storage performance for applications, such as power electronics in electrical vehicles. A recoverable energy density (Wrec) of ∼4.55 J cm–3with η ∼ 90% is achieved in lead-free relaxor BaTiO3-0.06Bi2/3(Mg1/3Nb2/3)O3ceramics at ∼520 kV cm–1. These ceramics may be co-fired with Ag/Pd, which constitutes a major step forward toward their potential use in the fabrication of commercial multilayer ceramic capacitors. Compared to stoichiometric Bi(Mg2/3Nb1/3)O3-doped BaTiO3(BT), A-site deficient Bi2/3(Mg1/3Nb2/3)O3reduces the electrical heterogeneity of BT. Bulk conductivity differs from the grain boundary only by 1 order of magnitude which, coupled with a smaller volume fraction of conducting cores due to enhanced diffusion of the dopant via A-site vacancies in the A-site sublattice, results in higher breakdown strength under an electric field. This strategy can be employed to develop new dielectrics with improved energy storage performance.

Ceria films grown on noble metal substrates have been widely studied as inverse model catalysts due to their high performance in various catalytic processes. Here, the oxygen vacancies formed in monolayered ceria islands on Pt(111) are explored by scanning tunneling microscopy and low-energy electron diffraction. The grown ceria forms (2 × 2) and (5 × 5) supercells to release the lattice strain due to their imperfect 3:4 lattice match with the underlying Pt(111) substrate lattice. The oxygen vacancies initially develop at the specific sites in the mismatched domains and subsequently grow into regular (3 × 3) supercells to link the mismatched domains.

Peripheral nerve injury is a common serious disease, and the electrical conductivity of nerve scaffolds is of special significance for nerve regeneration. Here, a highly conductive silk knitted composite scaffold was prepared by utilizing hydrogen bonding and electrostatic adsorption between silk amino, graphene (RGO), and polyaniline (PANI). Compared to traditional in situ polymerization of aniline (ANI), the surface of the RGO/PANI/silk conductive knitted scaffold prepared by two-step electrostatic self-assembly had more uniform PANI particles and lower resistance; when GO was 1 g/L and ANI was 0.4, 0.6, or 0.8 mol/L, the RGO/PANI/silk scaffold had better electrical properties when the conductivity was between 0.62 × 10–3and 1.72 × 10–3S/cm. The scaffolds had good conductive stability under different physical stresses and good mechanical properties, wherein ultimately the strength, elongation at break, and Young’s modulus ranges were 28.07–34.97 MPa, 105.91–109.85%, and 10.2–12.48 MPa, respectively, and so they provided good support. Conductive scaffolds had ordered loops, fiber structure, and large pore sizes between 40 and 70 μm. In summary, RGO/PANI/silk scaffold with good conductivity, pore size distribution, mechanical properties, thermal properties had potential applications in the field of peripheral nerve regeneration.

The vibration and noise generated by the boneless wiper-windshield system during its actual operation bother the occupants. Exploring the dynamic characteristics of the boneless wiper-windshield system is a prerequisite for understanding vibration and noise. In this paper, the dynamic characteristics of the boneless wiper-windshield system are investigated, and a rigid-flexible coupled multi-body dynamic model matching the real boneless wiper-windshield system is constructed. The friction characteristic of the dynamic model is studied through the wiper test bench experiment. The nonlinear dynamic response of the dynamic model is calculated with the Adams and results of the frictional vibration are well reproduced in real motions. The parallel analysis of the simulation calculation results and the real vehicle test results confirms the validity of the model. The results show that the vibration generation mechanism at the moments before and after the reversal can be explained by the instability of the wiper blades due to the negative friction characteristic. There are differences in the magnitude of the reversal impact force and the moment of reversal at each position of the wiper blade. The effect of the speed-gears on the system vibration is analyzed through the simulation results. The analysis method and simulation results in this article can provide reference for the research on vibration and noise control of boneless wiper systems.

Electrons not only serve as a “reactant” in redox reactions but also play a role in “catalyzing” some chemical processes. Despite the significance and ubiquitousness of electron-induced chemistry, many related scientific issues still await further exploration, among which is the impact of molecular assembly. In this work, microscopic insights into the vital role of molecular assembly in tweaking the electron-induced surface chemistry are unfolded by combined scanning tunneling microscopy and density functional theory studies. It is shown that the selective dissociation of a C–Cl bond in 4,4″-dichloro-1,1′:3′,1′′-terphenyl (DCTP) on Cu(111) can be efficiently triggered by an electron injection via the STM tip into the unoccupied molecular orbital. The DCTP molecules are embedded in different assembly structures, including its self-assembly and coassemblies with Br adatoms. The energy threshold for the C–Cl bond cleavage increases as more Br adatoms stay close to the molecule, indicative of the sensitive response of the electron-induced surface reactivity of the C–Cl bond to the subtle change in the molecular assembly. Such a phenomenon is rationalized by the energy shift of the involved unoccupied molecular orbital of DCTP that is embedded in different assemblies. These findings shed new light on the tuning effect of molecular assembly on electron-induced reactions and introduce an efficient approach to precisely steer surface chemistry.

The design of sulfur hosts with polar, sulfurphilic, and conductive network is critical to lithium-sulfur (Li-S) batteries whose potential applications are greatly limited by the lithium polysulfide shuttle effect. Mxenes, possessing layered-stacked structures and high electrical conductivities, have a great potential in sulfur hosts. Herein, sulfur nanoparticles uniformly decorated on titanium carbide Mxene (S@Ti3C2TxMxene) are synthesized via a hydrothermal method and then utilized as a cathode for lithium-sulfur batteries. This unique architecture could accommodate sulfur nanoparticles expansion during cycling, suppress the shuttling of lithium polysulfide, and enhance electronical conductivity. Consequently, the S@Mxene with a high areal sulfur loading (∼4.0 mg cm−2) exhibits a high capacity (1477.2 mAh g−1) and a low capacity loss per cycle of 0.18% after 100 cycles at 0.2 C. This work may shed lights on the development of high performance sulfur-based cathode materials for Li-S batteries.

The adsorption, assembly, and growth mechanism of the optoelectronic titanyl phthalocyanine (TiOPc) molecules on Au(111) were carefully investigated by low-temperature and high-resolution scanning tunneling microscopy (STM). Three domains, i.e., Y, I, and II, were formed on Au(111) with its coverage increased up to six monolayers (MLs), as structurally scrutinized at the submolecular level. The TiOPc molecules were adsorbed with their Pc planes parallel to the substrate surface in domains Y and I, while the Pc planes tilted against the surface with two lobes pointed toward the vacuum in domain II. A growth mode transition from layer-by-layer to bilayer-by-bilayer was experimentally observed in domains Y and I when the TiOPc coverage exceeded 2 ML, while domain II remained unchanged. The stable double-layer island growth, i.e., O-up and O-down in odd- and even-numbered layers, respectively, was maintained as the coverage increased in domains Y and I. Detailed structural analyses based on the submolecular resolution STM imaging indicated that domains Y, I, and II corresponded to polymorphic crystal phases Y-TiOPc, I-TiOPc, and deformed II-TiOPc grown on Au(111), which were frequently missed in previous studies due to the lack of subtle structural details by high-resolution images. Such a structural clarification of the grown TiOPc films should help in the understanding of the relationship between their optoelectronic device performance and polymorphism of the polycrystalline TiOPc thin films.

The electronic properties of thin oxide films supported on metal substrates have been the fundamental issues for supported model catalysts. Scanning tunneling microscopy (STM) can be employed to acquire the local information with measured tunneling current versus tip-sample distance (I–z) curves. In addition to the dipole moments of the thin film, charge transfer between the oxide film and metal substrate can also be determined. Here, the local work functions of the CeO2/Pt(111) and Cu2O/Cu(111) model systems are measured using the I–zspectroscopic mapping. The experimental results show that, unlike those for metal substrates, the work function measurements of the supported thin oxide layers via this methodology are strongly dependent on the applied bias voltages. However, only at low biases can highly reliable work functions be acquired. The work function change between one monolayer CeO2and bare Pt(111) substrate is −1.8 eV. Detailed analyses indicate that at higher bias voltages, the local work function measurement is severely perturbed by the electronic band structures of the thin oxide films. With the atomic resolution, local work functions of thin oxide layers supported by bulk metal substrates can be accurately determined by the STM I–zspectra, which is of great importance in explorations of surface electronic properties of thin oxide films.

Chirality transfer from self-assembly of achiral titanyl phthalocyanine (TiOPc) to its top-sitting TiOPc molecule has been successfully achieved. The TiOPc molecules first assemble into a porous network on Au(111) that contains periodic chiral voids, each being fenced by four axially rotating TiOPc molecules in upward adsorption geometry where their ending O atoms exclusively point away from the substrate. The additional top-sitting TiOPc molecule turns out to be chiral upon adsorption on a chiral void with its ending O atom toward the substrate. The chirality of the top-sitting TiOPc is associated with a charge transfer between its indole rings and the ending O atoms of the underlying TiOPc molecules that form the chiral void, resulting in asymmetric electronic density of the indole rings in the top-sitting molecule and accordingly the chirality of the molecular orbitals. Such a scenario also validates other planar achiral metallophthalocyanines such as copper phthalocyanine that become chiral upon adsorption on the chiral voids in the underlying TiOPc assembly, indicating that the chirality transfer mechanism from assembly to the top-sitting molecule is not uncommon.

Introduction Primary renal lymphoma is a rare malignant lymphoma that is difficult to differentiate from renal cell carcinoma. Positron emission tomography/computed tomography and image-guided percutaneous biopsy are valuable tools for diagnosis.Case report A 64-year-old woman presented with a 2-year history of repeated right waist pain and a 1-month history of nausea, vomiting, and frequent and urgent urination. A computed tomography scan showed a huge mass that was initially considered to be renal cell carcinoma at the upper pole of the right kidney. The mass had invaded the renal pelvis, narrowed the right renal artery, and constricted the inferior vena cava and liver. Postoperative examination of the tumor confirmed lymphoma. We herein present this case and its multidisciplinary team management.Conclusion Multidisciplinary team management is efficient for preoperative assessment and surgery in difficult and high-risk cases. Based on our literature review, we suggest biopsy before chemotherapy whenever possible. Chemotherapy can be implemented after surgery for better survival outcomes.

The self-assembly of 3,10-dibromo-perylo[1,12-b,c,d]thiophene on Ag(111) leads to three types of ordered porous networks: honeycomb PN1, Kagome PN2, and hybrid PN3. Detailed experimental and theoretical analyses confirm the thermal stability order of the three constructed porous networks. High-resolution scanning tunneling microscopy images indicate the importance of two σ-hole interactions of Br···S and Br···Br in steering two-dimensional molecular assembly on metal surfaces.

Background: Experimental animal model studies have shown neuroprotective properties of magnesium. We assessed the relationship between admission magnesium and admission stroke severity and 3-month clinical outcomes in patients with acute intracerebral hemorrhage (ICH). Methods: The present study included 323 patients with acute ICH who were prospectively identified. Demographic characteristics, lifestyle risk factors, National Institute of Health Stroke Scale (NIHSS) score, hematoma volumes, and other clinical features were recorded at baseline for all participants. Patients were divided into three groups based on the admission magnesium levels (T1: <0.84; T2: 0.84-0.91; T3: ≥0.91 mmol/L). Clinical outcomes were death, poor functional outcome (defined by modified rankin ccale [mRS] scores 3-6) at 3 months. Results: After 3-month follow-up, 40 (12.4%) all-cause mortality and 132 (40.9%) poor functional outcome were documented. Median NIHSS scores for each tertile (T1 to T3) were 8.0, 5.5, and 6.0, and median hematoma volumes were 10.0, 8.05, and 12.4 ml, respectively. There was no significant association between baseline NIHSS scores (P=0.176) and hematoma volumes (P=0.442) in T3 and T1 in multivariable linear regression models. Compared with the patients in T1, those in T3 were associated with less frequency of all-cause mortality [adjusted odds ratio (OR), 0.10; 95% confidence interval (CI), 0.02-0.54; P-trend=0.010] but not poor functional outcome (adjusted OR, 1.80; 95%CI, 0.71-4.56; P-trend=0.227) after adjustment for potential confounders. Conclusion: Elevated admission serum magnesium level is associated with lower odds of mortality but not poor functional outcome at 3 months in patients with acute ICH.

Background: The impact of Total Bile Acids (TBA) level on clinical outcomes after acute Intracerebral Hemorrhage (ICH) is still not understood. Objective: We investigated whether admission TBA level is associated with hematoma volume, stroke clinical severity, and 3-month outcomes in acute ICH patients. Methods: A total of 335 ICH patients were prospectively enrolled. Patients were divided into four groups, according to the quartiles of serum TBA level at the time of admission. Three-month outcomes were evaluated by interviews with patients or their family members. Results: The median hematoma volumes for the quartiles of TBA level (Q1 to Q4) were 12.0, 12.3, 10.0, and 6.7 mL (P<0.001) and the median National Institutes of Health Stroke Scale (NIHSS) scores were 8, 8, 6, and 5 (P=0.002), respectively. In the adjusted models, patients in the highest quartile (Q4) had smaller hematoma volumes (P=0.039) and lower NIHSS scores (P=0.037) than patients in Q1. At three months follow-up, there were 136 patients with poor outcomes (defined as having modified Rankin Scale scores≥3) and 46 cases of all-cause deaths. TBA level was not significantly associated with poor outcome nor all-cause death after adjusting for age, sex, hematoma volume, and baseline NIHSS(all P-trend≥0.380). Conclusions: Higher admission TBA was associated with smaller hematoma volume and decreased clinical severity, but not three month outcomes in patients with acute ICH.

Charge states of lanthanide double-decker phthalocyanines complexes significantly influence their geometrical structures and magnetic properties. In this study, the charge states of single DyPc2molecules on an ultrathin CuO film were detected by scanning tunneling microscopy and spectroscopy in magnetic fields. Four types of adsorptions of DyPc2molecules on CuO were experimentally observed. Without applying voltages, two of them were positively charged with the other two at the neutral state. By controlling the sample bias, two types of neutral molecules can be switched to the positively and negatively charged states, respectively. This manipulation was not realized for the DyPc2cations. A way to precisely detect the molecular charge states with and without current is beneficial for the development of molecular electronics.

Background: Previous clinical studies suggest that intravenous thrombolysis (IVT) with recombinant tissue plasminogen activator benefits stroke patients, but the efficacy of IVT in young stroke patients is not well-studied in China. Objective: We compared the safety and efficacy of IVT with recombinant tissue plasminogen activator between Chinese young stroke patients (18-50 years old) and older patients (51-80 years old). Method: We analyzed data from the Soochow Stroke Registry for 373 stroke patients (18-50 years, n=74 vs. 51-80 years, n=299) who received IVT between May 2009 and January 2016. Main outcomes included symptomatic intracerebral hemorrhage (sICH) within 7 days, and mortality and favorable outcome (modified Rankin scale 0-2) at 3 months. Associations between baseline characteristics and outcomes for the two groups were analyzed by logistic regression. Results: Favorable outcome at 3 months was significantly higher in young adults (adjusted odds ratio 2.09; 95% confidence interval 1.09-3.99, p=0.026). The incidence of sICH and mortality was low for young adults compared with older patients, but there were no statistically significant differences between the two groups. Multivariable analysis showed that baseline National Institutes of Health Stroke Score was associated with favorable outcome (p=0.026) in young adults. Conclusion: Our analysis indicated that young stroke patients treated with IVT had a more favorable outcome without an increased risk of sICH and mortality compared with older patients. We conclude that IVT is safe and at least as beneficial for Chinese young adults with acute ischemic stroke compared with older patients.

We propose a novel fifth-generation (5G) rapid prototyping system architecture by combining FPGA-privileged modules from a software defined radio (or FPGA-coprocessor) and high-level programming language for advanced algorithms from multi-core general purpose processors. The proposed system architecture exhibits excellent flexibility and scalability in the development of a 5G prototyping system. As a proof of concept, a multi-user full-dimension multiple-input and multiple-output system is established based on the proposed architecture. Experimental results demonstrate the superiority of the proposed architecture in large-scale antenna and wideband communication systems.

Abstract: There is active gravity flow sedimentation on the lower continental slope of Niger Delta. High-resolution 3-D seismic data enable a detailed study on the gravity flow deposition process and its impact. The lower continental slope of Niger Delta is characterized by a stepped complex topography, which resulted from gravity sliding and spreading during Miocene and Pliocene. Two types of accommodations are identified on the slope: ponded accommodation as isolated sub-basins and healed slope accommodation as connected tortuous corridors, where multi-scale submarine fans and submarine channels developed. Gravity flow deposition process is affected by the characteristics of gravity flows and the receiving basin. At the early stage, gravity flow deposition process was dominated by “fill and spill” pattern in the ponded accommodation, whereas it was confined to the healed slope accommodation during the late stage. On the lower continental slope of Niger Delta, complex slope topography controlled the distribution and evolution of the gravity flow, producing complicated gravity depositional patterns.

To investigate the feasibility, efficacy, and safety of endovascular recanalization for symptomatic chronic internal carotid artery occlusions (ICAO). Thirty patients with symptomatic chronic ICAO were treated using the endovascular recanalization method. Proximal balloon protection devices were used to prevent embolic migration by completely blocking the blood flow. The morphology of the internal carotid artery (ICA) at the occluded segment based on catheter angiography was analyzed. Recanalization of symptomatic chronic internal carotid artery occlusion (CICAO) was successful in 20 of the 30 patients (66.7%). The time required for successful revascularization ranged from 120 to 180 min (mean, 150 min). Of the 20 successful patients, 14 were at the cervical ICAs, and six were at the intracranial ICAs. No permanent complications occurred in our study. Ischemic symptoms related to chronic ICAO did not occur during the 18.3 month follow-up period (range, 12–24 months) in the 20 successful patients. Endovascular revascularization can improve hemodynamic compromise. The treated sites of all 20 successfully recanalized patients were patent on computed tomographic angiography or carotid duplex sonography, and no case with >50% restenosis was observed during the follow-up period. Three patients with failed recanalization had a stroke during the follow-up period. Endovascular revascularization of symptomatic CICAO using a proximal balloon protection device is technically feasible in selected patients, and the outcomes are favorable for patients who benefit from revascularization.

Objective Length of hospital stay is a sensitive indicator of short-term prognosis. In this retrospective study, we investigated how pancreas preservation time affects length of hospital stay after pancreas transplantation.Methods Patients receiving pancreas transplantation (1998.7–2018.6) were identified from the Scientific Registry of Transplant Recipients database and grouped according to pancreas preservation time. We analyzed the relationship of pancreas preservation time with graft and patient survival and prolonged length of stay (PLOS; i.e., hospital stay ≥20 days).Results We included 18,099 pancreas transplants in the survival analysis. Pancreas preservation time >20 hours had a significantly higher risk of graft failure than 8 to 12 hours. Pancreas preservation time was not significantly associated with patient survival. We included 17,567 pancreas transplants in the analysis for PLOS. Compared with 8 to 12 hours, pancreas preservation time >12 hours had a significantly higher PLOS risk, which increased with increased pancreas preservation time. In simultaneous pancreas–kidney transplantation, we also found that pancreas preservation time was positively associated with PLOS risk with pancreas preservation time >12 hours.Conclusion Pancreas preservation time is a sensitive predictor of PLOS. Transplant centers should minimize pancreas preservation time to optimize patient outcomes.

The electronic properties of halogens on the surface of metals have attracted substantial attention due to their promotion effects on surface molecular dehydrogenation reactions. Herein, the electronic properties of the submonolayer Br on Cu(111) were studied by combining scanning tunneling microscopy and density functional theory (DFT) calculations. The local work function of Br islands is found to range from 5.1 to 5.8 eV, which is higher than that of the Cu substrate (∼4.3 eV). Intriguingly, the Br atoms at the edge of islands possess a lower work function than the internal atoms, which originates from a larger local dipole induced by the stronger interfacial charge transfer between internal Br atoms and Cu, as supported by the DFT calculations. This phenomenon is in sharp contrast to the common intuition that the edge atoms tend to receive more charges from the substrate due to the contact with more neutral substrate atoms. Such a counterintuitive observation can be attributed to the stabilization of charged internal Br by neighboring atoms. These findings provide a deep insight of the interactions between halogen adsorbates and the metal surface, which leads to a comprehensive understanding of the microscopic mechanism of halogen-promoted reactions.

2.5 mm thick sheets of AA5052 were welded using friction stir welding technology. The effects of welding speed, rotational speed of pin, length of pin, single-side and double-side welding process on the morphology, microstructure and mechanical properties of welded joints were studied and analyzed. The failure mode was studied. The results show that the joints with good mechanical properties and without welding defects can be welded when the rotational speed of pin is 500-1200r/min and the welding speed is 100-480mm/min. The microstructure of weld nugget is mainly composed of a phase solid solution and b phase particles. The process parameters of friction stir welding have great influence on the static strength of welded joints. The static strength increases with the increasing of rotational speed of pin, however decreases with the increasing of welding speed. The peak load of the double-side welding increases by 30% compared with the single-side welding. The length of pin has little effect on the tensile strength. The tensile fracture of the single-side welding is located in the weld nugget zone, whereas the fracture of double-side welding is located in the base material zone.