A novel strategy for loading metal cocatalysts onto hollow nano-TiO_(2)inner surface with highly enhanced H_(2)production activity

The loading strategy of cocatalysts affects its activity exerting and atom utilization.Here,a novel strategy for loading precious metal(Pt)cocatalysts by means of ultrathin N-doped carbon layer is reported.The strategy is based on a pyrolysis process of predesigned N-containing polymers and Pt complexes on hard-template surface,during which Pt can be reduced by carbon from pyrolysis at high temperatures.Finally,the hollow TiO_(2)composite with stable and dispersed Pt on its inner surface was prepared.It shows an ultrahigh photocatalytic H_(2)production activity as high as 25.7 mmol h^(-1)g^(-1)with methanol as sacrificial regent,and displays an apparent quantum yield as 13.2%.The improved photocatalytic activity and stability can be attributed to the highly dispersed and ultrafine Pt nanoparticles,enhanced interaction between Pt-species and carbon support,fast photo-excited electron transport from the high graphitization degree of NC layers,ample oxygen vacancies/defects,as well as the manipulated local charge distribution of Pt/NC-layer configuration.Additionally,the universality of the proposed strategy was demonstrated by replacing metal sources(such as,Ru and Pd).This work presented a promising strategy for the design and development of novel photocatalysts,which shows a broad application prospect.

Regional Renewable Energy Optimization Based on Economic Benefits and Carbon Emissions

With increasing renewable energy utilization,the industry needs an accurate tool to select and size renewable energy equipment and evaluate the corresponding renewable energy plans.This study aims to bring new insights into sustainable and energy-efficient urban planning by developing a practical method for optimizing the production of renewable energy and carbon emission in urban areas.First,we provide a detailed formulation to calculate the renewable energy demand based on total energy demand.Second,we construct a dual-objective optimization model that represents the life cycle cost and carbon emission of renewable energy systems,after which we apply the differential evolution algorithmto solve the optimization result.Finally,we conduct a case study in Qingdao,China,to demonstrate the effectiveness of this optimizationmodel.Compared to the baseline design,the proposedmodel reduced annual costs and annual carbon emissions by 14.39%and 72.65%,respectively.These results revealed that dual-objective optimization is an effective method to optimize economic benefits and reduce carbon emissions.Overall,this study will assist energy planners in evaluating the impacts of urban renewable energy projects on the economy and carbon emissions during the planning stage.

Application of dynamic programming algorithm in winter heating control of greenhouse

In order to solve the immaturity of decision-making methods in the regulation of winter heating in greenhouses,this study proposed a solution to the problem of greenhouse winter heating regulation using a dynamic programming algorithm.A mathematical model that included indoor environmental state variables,optimization decision variables,and outdoor random variables was established.The temperature is kept close to the expected value and the energy consumption is low.The model predicts the control solution by considering the cost function within the next 10 steps.The two-stage planning method was used to optimize the state of each moment step by step.The temperature control strategy model was obtained by training the relationship between indoor temperature,outdoor temperature,and heating time after optimization using a regression algorithm.Based on a typical Internet of Things(IoT)structure,the greenhouse control system was designed to regulate the optimal control according to the feedback of the current environment.Through testing and verification,the optimized control method could stabilize the temperature near the target value.Compared to the threshold control(threshold interval of 2.0°C)under similar weather conditions,the optimized control method reduced the temperature fluctuation range by 0.9°C and saved 7.83 kW·h of electricity,which is about 14.56%of the total experimental electricity consumption.This shows that the dynamic programming method is feasible for environmental regulation in actual greenhouse production,and further research can be expanded in terms of decision variables and policy models to achieve a more comprehensive,scientific,and precise regulation.

Dynamic compression behavior of TiZrNbV refractory high-entropy alloys upon ultrahigh strain rate loading

In this study,the dynamic compressive response behavior of a body-centered cubic(BCC)single-phase TiZrNbV refractory high-entropy alloy(RHEA)was investigated under impact at speeds of 313-1584 m s^(-1)using two-stage,gas-gun-driven,high-speed plate-impact experiments;recovery sample analysis;and theoretical calculations.The strain rate and pressure were approximately 10^(7) s^(−1) and 5.07-29.37 GPa,respectively.The results showed that the TiZrNbV RHEA had a Hugoniot elastic limit of 4.12-5.86 GPa and a spall strength of 1.84-2.03 GPa.The initial yield strength of the alloy showed a strong strain-rate dependence and could be described by the modified Zerilli-Armstrong model,while the phonon-damping effect was the main reason for its high strain-rate sensitivity.Microstructural analysis showed that the dynamic deformation of the TiZrNbV RHEA was controlled by the dislocation slip,dislocation proliferation,intersection of the deformation bands,and grain refinement.The analysis also showed that the intergranular,transgranular,and mixed-type cracks dominated the spall failure of the material.The dynamic Hall-Petch effect and pinning from the lattice distortion led to high dynamic yield strength.The critical strain rate for the phonon drag effect was positively related to the relative atomic mass and local strain field of the metals.Within the experimental loading range,the RHEA showed good structural stability,and simultaneously,the theoretical calculation method for the equation of state based on a cold-energy mixture could accurately predict its shock-response behavior.The valence-electron concentration(VEC)had a direct effect on the shock-compression properties of the HEAs;higher VEC implied more difficulty in compressing the HEAs.The findings of this study provide insights into understanding the mechanical response characteristics of RHEAs under extreme conditions such as high-speed impact and ultrahigh strain-rate loading.

Achieving high strength and ductility in high-entropy alloys via spinodal decomposition-induced compositional heterogeneity

The compositional heterogeneity in high-entropy alloys(HEAs)has been reported to be an inherent en-tity,which significantly alters the mechanical properties of materials by tuning the variation of lattice resistance for dislocation motion.However,since the body-centered cubic(BCC)structure is not close-packed,the change of lattice resistance is less sensitive to the normal concentration wave compared to that in face-centered cubic(FCC)structured materials.In this work,we selected a refractory bcc HEAs TiZrNbTa for the matrix and added a small amount of Al to facilitate the special spinodal decomposition structure.In particular,(TiZrNbTa)98.5 Al 1.5 displayed a typical basket-weave fabric morphology of spinodal decomposition structure with a characteristic periodicity of∼8 nm and had an optimal combination of strength and ductility(the yield strength of 1123±9 MPa and ductility of∼20.7%±0.6%).It was de-termined that by doing in situ TEM mechanical testing,the plastic deformation was dominated by the formation and operation of dislocation loops which provided both edge and screw components of dislo-cations.The synergetic effect of the remarkable chemical heterogeneity created by the spinodal decompo-sition and the spreading lattice distortion in high entropy alloys is quite effective in tuning the mobility of different types of dislocations and facilitates dislocation interactions,enabling the combination of high strength and ductility.

Intratumoral CD103^(+)CD8^(+)T cells predict response to neoadjuvant chemoimmunotherapy in advanced head and neck squamous cell carcinoma

Background Immune cell heterogenicity is known to determine the therapeutic response to cancer progression.Neoadjuvant chemoimmunotherapy(NACI)has shown clinical benefits in some patients with advanced head and neck squamous cell carcinoma(HNSCC),but the underlying mechanism behind this clinical response is unknown.The efficacy of NACI needs to be potentiated by identifying accurate biomarkers to predict clinical responses.Here,we attempted to identify molecules predicting NACI response in advanced HNSCC.Methods We performed combined single-cell RNA sequencing(scRNA-seq)and multiplex immunofluorescence(mIHC)staining with tumor samples derived from NACI-treated HNSCC patients to identify a new tumor-infiltrating cell(TIL)subtype,CD103^(+)CD8^(+)TILs,associated with clinical response,while both in vitro and in vivo assays were carried out to determine its antitumor efficiency.The regulatory mechanism of the CD103^(+)CD8^(+)TILs population was examined by performing cell-cell interaction analysis of the scRNA-seq data and spatial analysis of the mIHC images.Results We established intratumoral CD103^(+)CD8^(+)TILs density as a determinant of NACI efficacy in cancers.Our scRNA-seq results indicated that the population of CD103^(+)CD8^(+)TILs was dramatically increased in the responders of NACI-treated HNSCC patients,while mIHC analysis confirmed the correlation between intratumoral CD103^(+)CD8^(+)TILs density and NACI efficacy in HNSCC patients.Further receiver operating characteristic curve analysis defined this TIL subset as a potent marker to predict patient response to NACI.Functional assays showed that CD103^(+)CD8^(+)TILs were tumor-reactive T cells,while programmed cell death protein-1(PD-1)blockade enhanced CD103^(+)CD8^(+)TILs cytotoxicity against tumor growth in vivo.Mechanistically,targeting the triggering receptor expressed on myeloid cells 2-positive(TREM2^(+))macrophages might enhance the population of CD103^(+)CD8^(+)TILs and facilitate antitumor immunity during NACI treatment.Conclusions Our study highlights the impact of intratumoral CD103^(+)CD8^(+)TILs density on NACI efficacy in different cancers,while the efforts to elevate its population warrant further clinical investigation.

相溶解协同提升高熵合金的强度和塑性

热处理是金属材料热机械加工的常用手段.随着热处理温度的升高而湮灭的缺陷通常导致材料的塑性提升而强度降低.本研究中,我们通过提高热处理温度促进相溶解而协同提升了TiZrNbTa高熵合金的强度和塑性.当热处理温度从800提升至1250°C,合金的拉伸屈服强度提高了40%,达到1003±16 MPa.同时,合金的伸长率增加了近一倍,达到16.79%±1.03%.热处理温度提升引起的相溶解加剧了晶格畸变,从而增强了晶格摩擦应力并提升了屈服强度.相溶解也降低了界面失配并缓解了应力集中.此外,1250°C热处理合金中的局部化学有序结构促进了位错共平面滑移和位错增殖.两种机制共同提升了合金的塑性.该研究不仅扩展了关于金属材料中热处理和相溶解的理解,而且也为合金的强韧化设计提供了思路.

新自由主义与民族主义的回潮:社会政策及其变化

在2015年以来右翼氛围浓郁的西方政治中,新自由主义和民族主义的回潮值得关注。本文考察了两者作为当今最强势的两支政治力量及其结合体对社会政策整体走向的影响。尽管新自由主义给全球社会造成了严重不良后果,但它对社会政策的影响依然稳固,甚至有强化之势。各式民族主义的回潮则对国家与地方产生了不同层次的社会政策影响,其民族民粹主义的形式正在蔓延。伴随代表政党崛起,一系列反全球化、反难民、反建制的“反对”主张登堂人室。近期最吸引人的景象是,看似根本对立的新自由主义与民族主义,却形成了价值观相通的默契联盟。这种新自由主义民族主义异军突起,给欧美社会政策增添了危险。

Role of gut microbiota in functional constipation

Functional constipation(FC)is common,yet the etiology is not clear.Accumulating evidence suggests an association between FC and abnormal gut microbiota.The relationship between the gut microbiota and the gut transit is likely bidirectional.This review summarizes the current evidence regarding the impact of gut microbiota on the pathogenesis of FC.By modulating the colonic motility,secretion,and absorption,gut microbiota may contribute to the development of FC through microbial metabolic activities involving bile acids,short-chain fatty acids,5-hydroxytryptamine,and methane.In support of the key roles of the gut microbiota in FC,treatment with probiotics,prebiotics,synbiotics,and traditional Chinese medicine often result in compositional and functional changes in the gut microbiota.Further studies on the pathogenesis of FC and the therapeutic mechanism of microecological agents will provide a knowledge base for better management of FC.

Microwave photonics: radio-over-fiber links, systems, and applications [Invited]

Microwave photonics(MWPs)uses the strength of photonic techniques to generate,process,control,and distribute microwave signals,combining the advantages of microwaves and photonics.As one of the main topics of MWP,radio-over-fiber(RoF)links can provide features that are very difficult or even impossible to achieve with traditional technologies.Meanwhile,a considerable number of signal-processing subsystems have been carried out in the field of MWP as they are instrumental for the implementation of many functionalities.However,there are still several challenges in strengthening the performance of the technology to support systems and applications with more complex structures,multiple functionality,larger bandwidth,and larger processing capability.In this paper,we identify some of the notable challenges in MWP and review our recent work.Applications and future direction of research are also discussed.

Semi-stability for Holomorphic Pairs on Compact Gauduchon Manifolds

In this paper,we establish a generalized Hitchin–Kobayashi correspondence between theτ-semi-stability and the existence of approximateτ-Hermitian–Einstein structure on holomorphic pair(E,φ)over the compact Gauduchon manifold.

Epigenetic regulation of prostate cancer

Prostate cancer is(PCa)the second leading cause of cancer death in males in the United State,with 174,650 new cases and 31,620 deaths estimated in 2019.It has been documented that epigenetic deregulation such as histone modification and DNA methylation contributes to PCa initiation and progression.EZH2(enhancer of zeste homolog 2),the catalytic subunit of the Polycomb Repressive Complex(PRC2)responsible for H3K27me3 and gene repression,has been identified as a promising target in PCa.In addition,overexpression of other epigenetic regulators such as DNA methyltransferases(DNMT)is also observed in PCa.These epigenetic regulators undergo extensive post-translational modifications,in particular,phosphorylation.AKT,CDKs,PLK1,PKA,ATR and DNA-PK are the established kinases responsible for phosphorylation of various epigenetic regulators.

Development levels of pediatric palliative care teams and the extent of palliative care understanding and implementation among pediatric oncologists in China

Importance:Pediatric palliative care(PPC)is an interdisciplinary collaboration that focuses on the prevention and relief of patient suffering.PPC has emerged as a critical field of medical expertise and practice.However,no information is available regarding the progress of PPC in the Chinese mainland.Objective:This study investigated the geographic distribution,team structure,and services of PPC teams in the Chinese mainland.It also investigated the level of understanding and implementation among pediatric oncologists regarding PPC.Methods:The PPC subspecialty group of the Pediatrics Society of the Chinese Medical Association included 45 PPC teams.The team structure and services were investigated using questionnaires mailed to the team leader of each PPC team.In addition,we sent questionnaires regarding the level of PPC understanding and implementation of PPC practices to 170 pediatric oncologists in 11 hospitals.Results:The geographical distribution of PPC teams is uneven in China.Most PPC teams are concentrated in the eastern provincial capital of China.Most PPC teams had limited staff and services.The level of PPC understanding was considerably limited across all demographics;most pediatric oncologists reported“some understanding”(n=71,41.8%)or“poor understanding”(n=50,29.4%).Only 62.9%of pediatric oncologists had experience providing advice to family members regarding PPC matters.Interpretation:China is currently experiencing a critical shortage of PPC resources.Most pediatric oncologists had a limited understanding of PPC and reported limited practical implementation of PPC,which leads to underutilization of PPC resources.

Handwashing quality assessment via deep learning:a modelling study for monitoring compliance and standards in hospitals and communities

Background Hand hygiene can be a simple,inexpensive,and effective method for preventing the spread of infectious diseases.However,a reliable and consistent method for monitoring adherence to the guidelines within and outside healthcare settings is challenging.The aim of this study was to provide an approach for monitoring handwashing compliance and quality in hospitals and communities.Methods We proposed a deep learning algorithm comprising three-dimensional convolutional neural networks(3D CNNs)and used 230 standard handwashing videos recorded by healthcare professionals in the hospital or at home for training and internal validation.An assessment scheme with a probability smoothing method was also proposed to optimize the neural network’s output to identify the handwashing steps,measure the exact duration,and grade the standard level of recognized steps.Twenty-two videos by healthcare professionals in another hospital and 28 videos recorded by civilians in the community were used for external validation.Results Using a deep learning algorithm and an assessment scheme,combined with a probability smoothing method,each handwashing step was recognized(ACC ranged from 90.64%to 98.87%in the hospital and from 87.39%to 96.71%in the community).An assessment scheme measured each step’s exact duration,and the intraclass correlation coefficients were 0.98(95%CI:0.97-0.98)and 0.91(95%CI:0.88-0.93)for the total video duration in the hospital and community,respectively.Furthermore,the system assessed the quality of handwashing,similar to the expert panel(kappa=0.79 in the hospital;kappa=0.65 in the community).Conclusions This work developed an algorithm to directly assess handwashing compliance and quality from videos,which is promising for application in healthcare settings and communities to reduce pathogen transmis-sion.