P-induced electron transfer interaction for enhanced selective hydrogenation rearrangement of furfural to cyclopentanone

Optimizing the intrinsic activity of non-noble metal by precisely tailoring electronic structure offers an appealing way to construct cost-effective catalysts for selective biomass valorization.Herein,we reported a P-doping bifunctional catalyst(Ni-P/mSiO_(2))that achieved 96.6%yield for the hydrogenation rearrangement of furfural to cyclopentanone at mild conditions(1 MPaH_(2),150°C).The turnover frequency of Ni-P/mSiO_(2)was 411.9 h^(-1),which was 3.2-fold than that of Ni/mSiO_(2)(127.2 h^(-1)).Detailed characterizations and differential charge density calculations revealed that the electron-deficient Niδ+species were generated by the electron transfer from Ni to P,which promoted the ring rearrangement reaction.Density functional theory calculations illustrated that the presence of P atoms endowed furfural tilted adsorb on the Ni surface by the C=O group and facilitated the desorption of cyclopentanone.This work unraveled the connection between the localized electronic structures and the catalytic properties,so as to provide a promising reference for designing advanced catalysts for biomass valorization.

Proximity Effect of Fe-Zn Bimetallic Catalysts on CO_(2) Hydrogenation Performance

The interaction between a promoter and an active metal crucially impacts catalytic performance.Nowadays,the influence of promoter contents and species has been intensively considered.In this study,we investigate the effect of the iron(Fe)-zinc(Zn)proximity of Fe-Zn bimetallic catalysts on CO_(2)hydrogenation performance.To eliminate the size effect,Fe_(2)O_(3)and ZnO nanoparticles with uniform size are first prepared by the thermal decomposition method.By changing the loading sequence or mixing method,a series of Fe-Zn bimetallic catalysts with different Fe-Zn distances are obtained.Combined with a series of characterization techniques and catalytic performances,Fe-Zn bimetallic proximity for compositions of Fe species is discussed.Furthermore,we observe that a smaller Fe-Zn distance inhibits the reduction and carburization of the Fe species and facilitates the oxidation of carbides.Appropriate proximity of Fe and Zn(i.e.,Fe_1Zn_(1)-imp and Fe_(1)Zn_(1)-mix samples)results in a suitable ratio of the Fe_5C_(2)and Fe_(3)O_(4)phases,simultaneously promoting the reverse water-gas shift and Fischer-Tropsch synthesis reactions.This study provides insight into the proximity effect of bimetallic catalysts on CO_(2)hydrogenation performance.

Theoretical investigation of loading Ni clusters on the α-Ga_2O_3 surfaces for photocatalytic hydrogen evolution

In the semiconductor-based photocatalysts for overall water splitting, loading proper cocatalysts play a crucial role in enhancing the photocatalytic activity. In this work, we have chosen Ni_n/α-Ga_2O_3 as a model and provided detailed density functional theory calculations to investigate the function of cocatalysts in hydrogen evolution reaction(HER). We have studied the formation and stability of Ni_n(n = 1–4) cluster on two stable surfaces of α-Ga_2O_3(001) and(012). In a Ni_n/α-Ga_2O_3 system, as the Ni 3d states well overlap with O and Ga states, the excited electrons transferred from Ga to Ni may participate in HER. We theoretically predict that introduction of Nincluster on(012) surface can elevate the Fermi level toward the conduction band, which is favorable for the occurrence of HER. Electrochemical computations are used to explore the mechanism of HER. It is found that, in most of Ni_n/α-Ga_2O_3 systems, the active sites of HER are on Ni_n clusters. Loading Ni_n clusters not only importantly reduces the Gibbs free energy of HER but also improves the reaction activity of surface O and Ga sites in HER. Our calculations reasonably explain the experimental observation on significant enhancement of activity for generating hydrogen after loading nickel oxide cocatalysts.

Running with Face Masks or Respirators Can Be Detrimental to the Respiratory and Cardiovascular Systems

Since the fi rst cases of coronavirus disease 2019(COVID-19)caused by severe acute respiratory syndrome coro-navirus 2(SARS-CoV-2)were reported at the end of 2019,this infection has spread around the globe,becoming a pandemic.The use of face masks and respirators is an important public health measure to reduce or prevent transmission of SARS-CoV-2.Here we discuss the hypothetical mechanisms by which exercise with face masks or respirators can induce detrimental effects on the cardiovascular system,potentially explaining adverse events such as cardiac arrhythmias and spontaneous pneumothorax.Although sudden death associated with the wearing of a face mask during running is a rare event,the risk is higher especially in those with existing cardiac comorbidities.In such cases,a mask designed specifi cally for runners with no or few side effects of oxygen defi ciency should be considered instead.

Analysis of Renewable Energy Research Hotspots and Trends Based on Bibliometric and Patent Survey

In recent years,renewable energy has taken on an increasingly important role as a result of the depletion of traditional fossil fuels and the pressure of climate change.Due to the advantages of clean energy production and wide availability,research on renewable energy has increased worldwide.We collected data from the Web of Science and the Derwent Innovations Index to analyze research trends in the field of renewable energy.It was found that the number of research achievements in this field has developed rapidly worldwide since 2005.The United States ranks first in the quantity and quality of literature and fourth in the number of authorized patents.China ranks second and first regarding the quantity of literature and authorized patents,respectively.Biomass energy,wind energy,and solar energy are trending research topics in various stages of development.China has maintained close cooperation with the United States,the United Kingdom,Australia,and other countries.

Reversing artemisinin resistance by leveraging thermo-responsive nanoplatform to downregulating GSH

Artemisinin(ART)resistance has been an emerging clinical problem,severely compromising antimalarial efficacy and threatening the global malaria elimination campaign.Albeit intensive studies about the molecular mechanism for ART resistance are under way,no effective therapeutic targets for reversing resistance have been applied.Here,we explore glutathione(GSH)as a therapeutic target to develop a thermo-responsive nanoplatform to specifically co-deliver ART and GSH synthesis inhibitor(L-buthionine sulfoximine,BSO)in a sustained manner,effectively reversing ART resistance in vivo.By combining with BSO,ART exerts increased antimalarial activity with reduced half-maximal inhibitory concentration(IC50)by 7.43-fold in ART-resistant strains.This work reveals that the GSH in ART-resistant parasites can be a promising therapeutic target for reversing ART resistance,paving the way for developing drug candidates and intelligent nanomedicines in malaria therapy.

Postprocessor development for ultrasonic cutting of honeycomb core curved surface with a straight blade

When ultrasonically cutting honeycomb core curved parts,the tool face of the straight blade must be along the curved surface’s tangent direction at all times to ensure high-quality machining of the curved surface.However,given that the straight blade is a nonstandard tool,the existing computer-aided manufacturing technology cannot directly realize the above action requirement.To solve this problem,this paper proposed an algorithm for extracting a straight blade real-time tool face vector from a 5-axis milling automatically programmed tool location file,which can realize the tool location point and tool axis vector conversion from the flat end mill to the straight blade.At the same time,for the multi-solution problem of the rotation axis,the dependent axis rotation minimization algorithm was introduced,and the spindle rotation algorithm was proposed for the tool edge orientation problem when the straight blade is used to machine the curved part.Finally,on the basis of the MATLAB platform,the dependent axis rotation minimization algorithm and spindle rotation algorithm were integrated and compiled,and the straight blade ultrasonic cutting honeycomb core postprocessor was then developed.The model of the machine tool and the definition of the straight blade were conducted in the VERICUT simulation software,and the simulation machining of the equivalent entity of the honeycomb core can then be realized.The correctness of the numerical control program generated by the postprocessor was verified by machining and accuracy testing of the two designed features.Observation and analysis of the simulation and experiment indicate that the tool pose is the same under each working condition,and the workpieces obtained by machining also meet the corresponding accuracy requirements.Therefore,the postprocessor developed in this paper can be well adapted to the honeycomb core ultrasonic cutting machine tool and realize high-quality and high-efficient machining of honeycomb core composites.

Multi-layer-structured bioactive glass nanopowder for multistage-stimulated hemostasis and wound repair

Current treatments for full-thickness skin injuries are still unsatisfactory due to the lack of hierarchically stimulated dressings that can integrate the rapid hemostasis,inflammation regulation,and skin tissue remodeling into the one system instead of single-stage boosting.In this work,a multilayer-structured bioactive glass nanopowder(BGN@PTE)is developed by coating the poly-tannic acid andε-polylysine onto the BGN via facile layer-by-layer assembly as an integrative and multilevel dressing for the sequential management of wounds.In comparison to BGN and poly-tannic acid coated BGN,BGN@PTE exhibited the better hemostatic performance because of its multiple dependent approaches to induce the platelet adhesion/activation,red blood cells(RBCs)aggregation and fibrin network formation.Simultaneously,the bioactive ions from BGN facilitate the regulation of the inflammatory response while the poly-tannic acid and antibacterialε-polylysine prevent the wound infection,promoting the wound healing during the inflammatory stage.In addition,BGN@PTE can serve as a reactive oxygen species scavenger,alleviate the oxidation stress in wound injury,induce the cell migration and angiogenesis,and promote the proliferation stage of wound repair.Therefore,BGN@PTE demonstrated the significantly higher wound repair capacity than the commercial bioglass dressing Dermlin™.This multifunctional BGN@PTE is a potentially valuable dressing for full-thickness wound management and may be expected to extend to the other wounds therapy.

Implementing Routine HIV Screening in Hospitals:An Effective Practice to Expand HIV Testing—Xishuangbanna Prefecture,Yunnan Province,China,2019–2020

Summary What is already known about this topic?Research evidence is insufficient to suggest whether routine human immunodeficiency virus(HIV)screening in healthcare settings is effective in promoting greater awareness of HIV-positive status.What is added by this report?This study found that,following the implementation of routine HIV screening in hospitals in Xishuangbanna Prefecture,Yunnan Province,there was a significant increase in the number of HIV screenings,positive results,and the positive rate of HIV screening in primary-level hospitals.What are the implications for public health practice?Routine hospital-based HIV screening is effective in identifying HIV infections in areas with concentrated epidemics.

Recent progress in stability of perovskite solar cells

Perovskite solar cells have attracted significant attention in just the past few years in solar cell research fields,where the power conversion efficiency was beyond 22.1%.Now,the most important challenge for perovskite solar cells in practical applications is the stability issue.In this mini-review,we will summarize the degradation mechanism of perovskite solar cells,including the perovskite material itself and also the interfaces.While we also provide our opinion on improving the stability of perovskite solar cells.

Immune-adjuvant loaded Bi2Se3 nanocage for photothermal-improved PD-L1 checkpoint blockade immune-tumor metastasis therapy

Checkpoint blockade based immune therapy has shown to be effective but benefit only the minority of patients whose tumors have been pre-infiltrated by T cells. To overcome this obstacles, a PEG-modified Bi2Se3 nanocage (NC) loaded with imiquimod (R848), which could efficiently destroy the tumors thus producing enough tumor-associated antigens (TAA) and with the existence of R848, a toll-like-receptor-7 agonist, could generate strong anti-cancer immune responses is reported in this study. Moreover, immunogenic Bi2Se3 NC-PEG/R848 mediated photothermal therapy (PTT) sensitizes tumors to checkpoint inhibition mediated by a PD-L1 antibody, not only ablating cancer cells upon NIR laser but also causing strong anti-cancer immunity to suppress distant tumor growth post PTT. Both in vitro and in vivo experiments demonstrate that the Bi2Se3 NC-PEG/R848 could effectively activate a PTT-induced immune response as well as silence immune resistance based on PD-L1 checkpoint blockade to ablate the primary tumor and further inhibit the tumor metastasis. Bi2Se3 NC reported here exhibits high photothermal conversion efficiency and stability, as well as competent drug loading capacity with large hollow structures and high surface area. Our study not only provides a facial way to synthesize Bi2Se3 NC, but also offers an alternative strategy for tumor metastasis.

Injectable self-healing ceria-based nanocomposite hydrogel with ROS-scavenging activity for skin wound repair

Excessive reactive oxygen species(ROS)in the injured skin may impede the wound repair and skin regeneration.Herein,we develop an injectable self-healing ceria-based nanocomposite hydrogel with ROS-scavenging activity to accelerate wound healing.The nanocomposite hydrogels were successfully prepared by coating cerium oxide nanorods with polyethylenimine and crosslinked with benzaldehyde-terminated F127(F127-CHO)through the dynamic Schiff-base reaction(FVEC hydrogel).The results showed that the FVEC hydrogel possessed the good thermosensitivity,injectability,self-healing ability and ROS scavenging activity.The subcutaneous implantation experiments in mice confirmed that FVEC hydrogels are biocompatible and biodegradable in vivo.The fullthickness skin wound studies showed that FVEC hydrogel could significantly enhance the wound healing and epithelium regeneration with the formation of hair follicle and adipocyte tissue.This work provides a new strategy for the development of multifunctional Cebased nanocomposite hydrogel for full-thickness skin wound healing and regeneration.

Effects of inclination angles of disc cutter on machining quality of Nomex honeycomb core in ultrasonic cutting

Ultrasonic cutting with a disc cutter is an advanced machining method for the high-quality processing of Nomex honeycomb core.The machining quality is influenced by ultrasonic cutting parameters,as well as tool orientations,which are determined by the multi-axis machining requirements and the angle control of the cutting system.However,in existing research,the effect of the disc cutter orientation on the machining quality has not been studied in depth,and practical guidance for the use of disc cutters is lacking.In this work,the inclined ultrasonic cutting process with a disc cutter was analyzed,and cutting experiments with different inclination angles were conducted.The theoretical residual height models of the honeycomb core,as a result of the lead and tilt angles,were established and verified with the results obtained by a linear laser displacement sensor.Research shows that the residual height of the honeycomb core,as a result of the tilt angle,is much larger than that as a result of the lead angle.Furthermore,the tearing of the cell wall on the machined surface was observed,and the effects of the ultrasonic vibration,lead angle,and tilt angle on the tear rate and tear length of the cell wall were studied.Experimental results revealed that ultrasonic vibration can effectively decrease the tearing of the cell wall and improve the machining quality.Changes in the tilt angle have less effect than changes in the lead angle on the tearing of the cell wall.The determination of inclination angles should consider the actual processing requirements for the residual height and the machining quality of the cell wall.This study investigates the influence of the inclination angles of a disc cutter on the machining quality of Nomex honeycomb core in ultrasonic cutting and provides guidelines for machining.

Mediator complex subunit 12 is a gatekeeper of SARS-CoV-2 infection in breast cancer cells

Cancer patients are at increased risk for severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infection and mortality.Like other viruses in the SARS family,SARS-CoV-2 employs two host proteins,angiotensin-converting enzyme 2(ACE2)and transmembrane serine protease 2(TMPRSS2),for viral entry.1 Recent studies showed that many of the host proteins identified as potential targets for developing COVID therapies are dysregulated in cancer,2 prompting us to investigate whether human cancer cells are susceptible to SARS-CoV-2 infection,and whether chemotherapy could modulate a cancer patient's risk for infection.

Temperature dependence of the heterogeneous uptake of acrylic acid on Arizona test dust

In this study, the temperature dependence of the heterogeneous uptake of acrylic acid on Arizona test dust （ATD） has been investigated within a temperature range of 255-315 K using a Knudsen cell reactor. Combined with diffuse reflectance infrared Fourier transform spectroscopy （DRIFTS） experiment, it was found that acrylic acid could adsorb on ATD via surface OH groups and convert to carboxylate on the particle surface. The kinetics study suggests that the initial true uptake coefficient （yt） of acrylic acid on ATD decreases from （4.02 ± 0.12） x 10-5 to （1.73 ± 0.05） x 10-5 with a temperature increase from 255 to 315 K. According to the temperature dependence of uptake coefficients, the enthalpy （AHobs） and entropy （ASobs） of uptake processes were determined to be -（9.60± 0.38） KJ/mol and -（121.55 ± 1.33） l.K/mol, respectively. The activation energy for desorption （Edes） was calculated to be （14.57 ± 0.60） KJ/mol. These results indicated that the heterogeneous uptake of acrylic acid on ATD surface was sensitive to temperature. The heterogeneous uptake on ATD could affect the concentration of acrylic acid in the atmosphere, especially at low temperature.

Relationship of Microchannels and Plaque Erosion in Patients with ST-Segment Elevation Myocardial Infarction: An Optical Coherence Tomography Study

Objective:Microchannels are associated with the progression of atherosclerotic vulnerable plaques.However,in patients with culprit optical coherence tomography(OCT)-defined plaque erosion,the knowledge of microchannels and culprit lesion vulnerability is limited.The aim of this study was to investigate culprit lesion characteristics in patients with ST-segment elevated myocardial infarction(STEMI)caused by plaque erosion with and without microchannels using OCT.Methods:In all,348 STEMI patients with plaque erosion who underwent OCT of the culprit lesion at the 2nd Affiliated Hospital of Harbin Medical University(Harbin,China)from August 2014 to December 2017 were included and divided into the microchannel group(n=116,33.3%)and no-microchannel group(n=232,66.7%).The clinical characteristics and OCT-derived plaque features were compared between both groups.Results:Among the 348 STEMI patients with plaque erosion,culprit lesions with microchannels had higher incidence of lipid plaque(59.5%vs.45.3%,P=0.012);calcification(41.4%vs.24.6%,P=0.002);spotty calcification(30.2%vs.18.1%,P=0.014);macrophages accumulation(72.4%vs.45.7%,P<0.001);and cholesterol crystals(32.8%vs.14.2%,P<0.001)than those without microchannels.In addition,minimal lumen area was smaller((1.9±0.9)mm2 vs.(2.8±2.3)mm2,P<0.001)and lumen area stenosis was greater((71.3%±13.4%)vs.(65.3%±19.3%),P=0.001)in the microchannel group than in the no-microchannel group.Conclusion:In patients with STEMI caused by plaque erosion,one-third manifested typical microchannel characteristics,and those with microchannels were associated with more severe luminal stenosis and more vulnerable plaque features than those without microchannels.

CIRS:A Confidence Interval Radius Slope Method for Time Series Points Based on Unsupervised Learning

The rise of big data has brought various challenges and revolutions to many fields.Even though its development in many industries has gradually become perfect or even mature,its application and development in complex industrial scenarios is still in its infancy.We run research on single-dimensional time series point anomaly detection based on unsupervised learning:Unlike periodic time series,aperiodic or weakly periodic time series in industrial scenarios are more common.Considering the need for online real-time monitoring,we need to solve the problem of point anomaly detection of oil chromatographic characteristic gases.Thus,we propose a sliding window-based method for the unsupervised single-dimensional time series point anomaly detection problem called the confidence interval radius slope method(CIRS).CIRS is a fusion of knowledge-driven and data-driven methods to realize online real-time monitoring of possible data quality problems.From the experimental results,CIRS has obtained higher PR values than other unsupervised methods by the subject data.