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An oxidative cascade iodocyclization of 1,7- or 1,8-dienes has been realized under mild conditions. By employing I2as an iodine source, this protocol provides a concise and efficient approach to a great deal of biologically significant iodinated benzo[b]azepine and benzo[b]azocine derivatives in moderate to good yields. The gram-scale synthesis and further transformation of products render the approach practical and attractive. Radical trapping and deuterium-labeling experiments help to understand the mechanism.

AbstractObjectivesThe purpose of this study was to measure and examine the levels of IgG, IgM, and Spike antibody induced by inactivated vaccines, including CoronaVac and BBIBP-CorV.MethodsTwo groups of healthy adults over 18 years old (50 participants per group), who had previously received 1 dose of either BBIBP-CorV or CoronaVac and receiving either a homologous booster of BBIBP-CorV or a heterologous booster of CoronaVac. Serum IgG, IgM, and Spike antibody levels against SARS-COV-2 were measured using magnetic particle chemiluminescence immunoassay and the ELISA method.ResultsThe results showed that both spike antibody and IgG/IgM antibodies elicited by a CoronaVac booster following 1 dose of BBIBP-CorV were significantly higher than those elicited by either a homologous BBIBP-CorV booster or a heterologous BBIBP-CorV booster. The Spike antibody against SARS-COV-2 induced by the heterologous CoronaVac booster reached 200.3, which is substantially greater than that induced by the homologous BBIBP-CorV booster (127.5 pg/mL). Conversely, the Spike antibody against SARS-COV-2 induced by the heterologous BBIBP-CorV booster reached 53.93 pg/mL, which is substantially greater than that induced by the homologous CoronaVac booster (9.60 pg/mL).ConclusionsIn summary, CoronaVac is immunogenic as a booster dose following 1 dose of BBIBP-CorV and is immunogenically superior to both the homologous booster and the heterologous BBIBP-CorV booster.

The shortage of skin for grafting continues to be a major problem in the treatment of serious skin injuries. 3D bioprinting provides a new way to solve this problem. However, current 3D printed skin is less effective in treatment of large wounds because of severe shrinkage and scarring. In this study, bionically designed bilayer skin was fabricated using an extrusion-based bioprinter and a gelatin/sodium alginate/gelatin methacrylate hydrogel with excellent physical and biological properties. Full-thickness skin wounds were created in the back of nude mice and treated with bioprinted skin or hydrogel. Bioprinted skin accelerated wound healing, reduced wound contraction and scarring, and facilitated wound skin epithelialization compared with the bioprinted hydrogel or untreated wound. The skin from the wound was collected 28 days after grafting for histology and immunofluorescence analysis. The thickness of the dermis and epidermis of the bioprinted skin was similar to that of nude mice. Microvascular formation in the dermis and dense keratinocytes in the epidermis of the bioprinted skin were observed. This study provides a potential treatment strategy for reducing skin contraction and scar in large skin wounds.

3D printing has made remarkable progress in soft tissue reconstruction enabling the custom design of complex material implants with patient specific geometry. The aim of this study was to inkjet print mechanically reinforced biocompatible hydrogels. Here, we developed a double crosslinked ink by optimizing the rheological properties of solutions of sodium alginate (NaAlg), NaAlg/transglutaminase (TG), CaCl2and gelatin/CaCl2. The results showed that a two-component ink system comprising NaAlg (4% w/v)/TG (0.8% w/v) and gelatin (4% w/v)/CaCl2(3% w/v) gave optimum printability. The mechanical and biological properties of printed alginate/gelatin hydrogels prepared from inks with different gelatin contents, and incorporated fibroblasts, were characterized by Scanning Electron Microscope (SEM), mechanical testing and laser confocal microscopy. The compressive moduli of alginate/gelatin hydrogels could be adjusted from 19.2 kPa ± 1.2 kPa to 65.9 kPa ± 3.3 kPa by increasing the content of gelatin. After incubation for 7 d, fibroblasts had permeated all printed hydrogels and the rate of proliferation increased with increasing gelatin content. The highest cell proliferation rate (497%) was obtained in a hydrogel containing 4.5% (w/v) gelatin. This study offers a new strategy for the fabrication of 3D structures used to mimic the function of native tissues.

Berry phase and Berry curvature play a key role in the development of topology in physics and do contribute to the transport properties in solid state systems. In this paper, we report the finding of novel nonzero Hall effect in topological material ZrTe5flakes when the in-plane magnetic field is parallel and perpendicular to the current. Surprisingly, both symmetric and antisymmetric components with respect to magnetic field are detected in the in-plane Hall resistivity. Further theoretical analysis suggests that the magnetotransport properties originate from the anomalous velocity induced by Berry curvature in a tilted Weyl semimetal. Our work not only enriches the Hall family but also provides new insights into the Berry phase effect in topological materials.

Integration of transition metal dichalcogenides (TMDs) on ferromagnetic materials (FM) may yield fascinating physics and promise for electronics and spintronic applications. In this work, high-temperature anomalous Hall effect (AHE) in the TMD ZrTe2thin film using a heterostructure approach by depositing it on a ferrimagnetic insulator YIG (Y3Fe5O12, yttrium iron garnet) is demonstrated. In this heterostructure, significant anomalous Hall effect can be observed at temperatures up to at least 400 K, which is a record high temperature for the observation of AHE in TMDs, and the large RAHEis more than 1 order of magnitude larger than those previously reported values in topological insulators or TMD-based heterostructures. A complicated interface with additional ZrO2and amorphous YIG layers is actually observed between ZrTe2and YIG. The magnetization of interfacial reaction-induced ZrO2and YIG is believed to play a crucial role in the induced high-temperature AHE in the ZrTe2. These results present a promising system for the spintronic device applications, and it may shed light on the designing approach to introduce magnetism to TMDs at room temperature.

ZrTe2is a candidate topological material from the layered two-dimensional transition-metal dichalcogenide family, and thus the material may show exotic electrical transport properties and may be promising for quantum device applications. In this work, we report the successful growth of layered ZrTe2thin film by pulsed-laser deposition and the experimental results of its magnetotransport properties. In the presence of a perpendicular magnetic field, the 60 nm thick ZrTe2film shows a large magnetoresistance of 3000% at 2 K and 9 T. A robust linear magnetoresistance is observed under an in-plane magnetic field, and negative magnetoresistance appears in the film when the magnetic field is parallel to the current direction. Furthermore, the Hall results reveal that the ZrTe2thin film has a high electron mobility of about 1.8 × 104cm2V–1s–1at 2 K. These findings provide insights into further investigations and potential applications of this layered topological material system.

Tumor‐associated macrophages (TAMs) are important immune cells in the tumor microenvironment (TME). The polar plasticity of TAMs makes them important targets for improving the immunosuppressive microenvironment of tumors. The previous study reveals that layered double hydroxides (LDHs) can effectively promote the polarization of TAMs from the anti‐inflammatory M2 type to the pro‐inflammatory M1 type. However, their mechanisms of action remain unexplored. This study reveals that LDHs composed of different cations exhibit distinct abilities to regulate the polarity of TAMs. Compared to Mg–Fe LDH, Mg–Al LDH has a stronger ability to promote the repolarization of TAMs from M2 to M1 and inhibit the formation of myeloid‐derived suppressor cells (MDSCs). In addition, Mg–Al LDH restrains the growth of tumors in vivo and promotes the infiltration of activated immune cells into the TME more effectively. Interestingly, Mg–Al LDH influences the autophagy of TAMs; this negatively correlates with the pro‐inflammatory ability of TAMs. Therefore, LDHs exert their polarization ability by inhibiting the autophagy of TAMs, and this mechanism might be related to the ionic composition of LDHs. This study lays the foundation for optimizing the performance of LDH‐based immune adjuvants, which display excellent application prospects for tumor immunotherapy. Layered double hydroxides (LDHs) can induce the repolarization of tumor‐associated macrophages toward M1‐type to improve the tumor immunosuppressive microenvironment by blocking the occurrence of autophagy, and this blocking effect might be related to the cationic composition of LDHs, in which Al3+plays an important role.

Graphical Abstract: “Electrons pump” effect of CeO2ensures that interface-engineered Ni2P@CeO2hybrid nanoarrays prepared via selective-phosphorization treatment present superior HER catalytic performance

Objective This study aimed to investigate the damage pattern of the stress transfer path (STP) for the Japanese Investigation Committee (JIC) classification of pre-collapse osteonecrosis of the femoral head. We aimed to provide a specific biomechanical basis for treatment decisions of each subtype.Methods Five computational models were used in the experiment. Different necrotic classifications were simulated based on the JIC classification system. Damage patterns of the STP were used for qualitative assessment and average stresses were used for quantitative analysis.Results The STP of type A showed a strong similarity to the healthy level, which was consistent with the bone density distribution in X-rays and previous simulations results. The damaged area of principal stress of type B was approximately 25% of the healthy level. The STPs of types C1 and C2 were broken and the damaged areas of principal stress were more than 50% of the healthy level. The efficiency of stress transfer was reduced.Conclusions These results indicate that the damage patterns and stress transfer efficiency of the femoral head are associated with necrotic classifications.

Water pollutants, often containing insoluble oils, soluble dyes, and pathogenic bacteria in wastewater, have threatened ecosystem security and human health, making great challenges for water purification and wastewater treatment. Considering the variety and complexity of water pollutants in wastewater, the development of a versatile material for complex wastewater cleanup with one single-step procedure is highly desirable. Herein, a biomimetic superwetting CuSx-based composite mesh is constructed as a versatile platform for all-in-one water purification. In this procedure, the hierarchical micro/nanoscale CuSxstructures are controllably generated on Cu mesh surface via a single-step solvothermal process, endowing CuSx-based composite mesh with special switchable surface wettability, efficient photocatalytic capability and excellent photothermal antibacterial activity. Owing to its special switchable surface wettability, this superwetting CuSx-based composite mesh firstly demonstrates the reversible oil/water separation with high separation efficiency, robust durability and good reusability. Moreover, such superwetting CuSx-based composite mesh simultaneously reveals the efficient photodegradation towards organic dye contaminants and the enhanced photothermal antibacterial properties against Escherichia coliand Staphylococcus aureusin water under light illumination. With respect to these features, this superwetting CuSx-based composite mesh can simultaneously clean up those complex contaminants from wastewater, showing the promising potential in advanced water purification and wastewater treatment.

In the total hip arthroplasty (THA), the optimal administration route of tranexamic acid (TXA) remains controversial. This study was designed to investigate the impact of topical injection of TXA on blood loss during primary unilateral THA as well as short-term safety and adverse side effects compared with intravenous administration of TXA. In this study, 75 patients who underwent unilateral THA were randomly divided into 3 groups receiving intra-articular TXA (IA group), intravenous TXA (IV group) or no TXA (control group C). Blood loss, postoperative drainage, covert blood loss, total blood volume, the number of blood transfusions after surgery and transfusion rate, incidence of deep venous thrombosis and pulmonary embolism were recorded and evaluated in the three groups after 1 week and 1 month. There were significant differences in the quantity of postoperative drainage, covert blood loss, total blood volume, the number of blood transfusions after surgery and transfusion rates between the three groups (P< 0.05), but blood loss during surgery showed no significant differences among the three groups (P> 0.05). In the IV group, 1 patient suffered from deep venous thrombosis of the lower limbs and in the C group, 2 patients suffered from superficial venous thrombosis of the lower limbs 2 and 4 days after surgery, respectively. In the IA group no complications occurred during the follow-up period. Preoperative intravenous TXA and postoperative topical TXA significantly reduced postoperative blood loss and transfusion rates among the patients who underwent primary unilateral THA and the short-term safety was good. The data suggest that topical injection of TXA is safer and more effective, without postoperative complications. Der optimale Weg der Tranexamsäure(TXA)-Applikation im Rahmen der Hüfttotalendoprothese ist weiterhin umstritten. In der vorliegenden Studie sollten der Effekt einer topischen TXA-Injektion auf den Blutverlust während einer einseitigen Hüfttotalendoprothese, die kurzfristige Sicherheit und unerwünschte Wirkungen untersucht werden, jeweils im Vergleich zur intravenösen TXA-Applikation. In dieser Studie wurden 75 Patienten, die eine einseitige Hüfttotalendoprothese erhielten, in 3 Gruppen randomisiert. Sie erhielten intraartikulär TXA (i.a.-Gruppe), intravenös TXA (i.v.-Gruppe) oder keine TXA (Kontrollgruppe). Dokumentiert und ausgewertet wurden Blutverluste, die postoperative Drainage, versteckte Blutverluste, das Gesamtblutvolumen, die Zahl der Bluttransfusionen nach chirurgischem Eingriff, die Transfusionsrate sowie die Inzidenz von tiefen Venenthrombosen und Lungenembolien, jeweils nach einer Woche und einem Monat in den drei Gruppen. Es fanden sich signifikante quantitative Unterschiede zwischen den drei Gruppen in postoperativer Drainage, versteckten Blutverlusten, dem Gesamtblutvolumen, der Zahl der Bluttransfusionen nach chirurgischem Eingriff und in der Transfusionsrate (p< 0,05). Keine signifikanten Unterschiede zeigten sich dagegen im Blutverlust während des chirurgischen Eingriffs (p> 0,05). In der i.v.-Gruppe kam es bei einem Patienten zu einer tiefen Venenthrombose der unteren Extremitäten. In der Kontrollgruppe erlitten 2 Patienten eine oberflächliche Venenthrombose der unteren Extremitäten (2 bzw. 4 Tage nach dem Eingriff). Bei den Patienten der i.a.-Gruppe ereigneten sich in der Follow-up-Phase keine Komplikationen. Die präoperative i.v.-Applikation und postoperative topische Applikation von TXA reduzierten signifikant den postoperativen Blutverlust und die Transfusionsrate bei Patienten, die einer primären einseitigen Hüfttotalendoprothese unterzogen wurden. Die kurzfristige Sicherheit war gut. Die Ergebnisse deuten darauf hin, dass die topische Injektion von TXA sicherer und wirksamer ist, ohne dass es dabei zu postoperativen Komplikationen kommt.

Using a variable air volume ventilation system is an efficient way to save energy in the tunnel. To address the issues of low control parameter accuracy and high operating energy consumption, the transient flow field and ventilation resistance characteristics were analyzed using conservation equations, and the first-order delay mathematical model of tunnel ventilation control was established by taking tunnel and jet fan parameters into account. The airflow dynamic control model's related parameters and transfer function were also solved. The overshoot, steady value, and adjustment time of the control system were evaluated using simulation and experiment. In full-scale experiments, the required wind speed was converted into the frequency of the jet fans to achieve variable air volume ventilation control. The results show that the variable air volume ventilation control system has the characteristics of nonlinear, and the first-order delay time transfer function is related to the 1/2-th power of ventilation resistance and pressure. The control system performs well, and the response parameters are all within the error range. Moreover, the discussion results of the comparative tests also illustrated that the purpose of dynamic wind speed adjustment could be achieved through frequency conversion control.

A novel visible-light-promoted selective sulfonylation and selenylation of dienes with selenosulfonates has been developed. This technology provides mild access to a wide range of sulfonyl benzo[b]azepinones and seleno-benzo[b]azepines. Preliminary mechanistic studies suggest that the sulfonylation involves a sulfonyl radical engaged cascade process, and the selenylation is accomplished through a sequential oxidation/electrophilic cyclization process. The large-scale operation and late-stage modification experiment reveal the promising utility of this protocol.

Three-dimensional (3D) Dirac semimetals, which possess 3D linear dispersion in the electronic structure as a bulk analogue of graphene, have lately generated widespread interest in both materials science and condensed matter physics. Recently, crystalline Cd3As2has been proposed and proved to be a 3D Dirac semimetal that can survive in the atmosphere. Here, by using point contact spectroscopy measurements, we observe exotic superconductivity around the point contact region on the surface of Cd3As2crystals. The zero-bias conductance peak (ZBCP) and double conductance peaks (DCPs) symmetric around zero bias suggest p-wave-like unconventional superconductivity. Considering the topological properties of 3D Dirac semimetals, our findings may indicate that Cd3As2crystals under certain conditions could be topological superconductors, which are predicted to support Majorana zero modes or gapless Majorana edge/surface modes in the boundary depending on the dimensionality of the material.

In the last several years, bone tumor related microRNA research showed an explosive growth. MicroRNA was found to have a high or low expression level in bone tumor tissue and some microRNAs proved to be the biomarker for poor prognosis. The majority of research was focused on osteosarcoma and Ewing sarcoma. Many tumor associated molecules, including oncogenes and tumor suppressor genes, were found to be the direct targets for microRNA, and enhanced microRNA may play the regulatory role in tumor development. In the bone tumor cell lines, overexpression of microRNA could promote or inhibit the tumor growth, migration, invasion, and metastasis, especially for osteosarcoma and Ewing sarcoma. Many key molecules proved important for tumor genesis were found directly binding to the related microRNA, and whose expression level was down regulated. This may provide a novel therapeutic target for bone tumor. Large scale clinical samples detection and high through-put microarray assay have demonstrated microRNA might be applied to predict and diagnose the bone tumor. MicroRNA in serum was also proved significant as a biomarker for bone tumor.

This study demonstrates the design and synthesis of the Cu0.5Ir1–xZrxTe2(0 ≤ x≤ 0.15) system by partial substitution of Ir with Zr acting as a negative chemical pressure. With the doping of Zr, the cell parameters significantly expand, signifying an effective negative chemical pressure. The experimental results find evidence that the charge density wave (CDW)-like order is immediately quenched by subtle Zr substitution for Ir and a classical dome-shape Tc(x) that peaked at 2.80 K can be observed. The optimal Cu0.5Ir0.95Zr0.05Te2compound is a Bardeen–Cooper–Schrieffer (BCS)-type superconductor and exhibits type-II superconductivity (SC). However, high Zr concentrations (x> 0.1) can provoke disorders, inducing the reappearance of CDW orders. The present study shows that the Cu0.5Ir1–xZrxTe2(0 ≤ x≤ 0.15) system may provide a new platform for further understanding multiple electronic orders in transition-metal dichalcogenides.

Achieving high thermoelectric performance in thin film heterostructures is essential for integrated and miniatured thermoelectric device applications. In this work, we demonstrate a mechanism and device performance of enhanced thermoelectric performance induced by interfacial effect in a transition metal dichalcogenides-SrTiO3(STO) heterostructure. Owing to the formed conductive interface and elevated conductivity, the ZrTe2/STO heterostructure presents large thermoelectric power factor of 3.7 × 105μWcm−1K−2 at 10 K. Formation of quasi-two-dimensional conductance at the interface is attributed for the large Seebeckcoefficient and high electrical conductivity, leading to high thermoelectric performance which is demonstrated by a prototype device attaining 3 K cooling with 100 mA current input to this heterostructure. This superior thermoelectric property makes this heterostructure a promising candidate for future thermoelectric device.

In this study, we present a two-dimensional dynamic model for incompressible flows to investigate the mechanisms that determine the dynamic transition and structure of granulation convection in the solar photosphere near the equator. First, we establish the critical value of the Rayleigh number, which represents the necessary condition for the occurrence of granulation convection. This critical value is determined by affirming the validity of the Principle of Exchange of Stabilities conditions within our dynamic model. Second, we study the dynamic transition of the dynamic model from the perspective of the Phase transition dynamics established by Ma and Wang [18]. Our results show that the dynamic model experiences a continuous transition, where the system bifurcates from a basic steady-state to an attractor , each element of which represents a distinct structure of granulation convection.