Construction of 3D Shape-Changing Hydrogels via Light-Modulated Internal Stress Fields

The 3D shape-changing hydrogels are highly pursued for numerous applications.However,up to now,the construction of complex 3D shape-changing hydrogels remains a challenge.The reported design strategies are mainly applied to fabricate 2D ones by introducing anisotropic microstructures into hydrogel sheets/membranes.Herein,we present a convenient photolithography strategy for constructing complex 3D shape-changing hydrogels by simultaneously modulating anisotropic microstructures and internal stress fields of gel sheets.When the precursor solution containing ultraviolet(UV)absorber is irradiated by single-side UV light,the attenuated polymerization rate can cause the generation of asymmetric internal stress field in the resulting hydrogel sheet.In the meantime,the directional diffusion of unpolymerized monomers allows for the formation of vertical gradient structure within hydrogel.Therefore,by applying different photomasks to modulate the local gradient structures and internal stress fields of the gel sheets,they can spontaneously transform into various complex 3D shape-changing hydrogels in the air.Response to the external stimuli,these 3D shape-changing hydrogels(e.g.,fighter plane,birdie,and multi-storey origami lattices)can deform in a novel 3D_(1)-to-3D_(2)-to-3D_(3)mode.This new design strategy contributes to the development of complex biomedical implants and soft robotics.

晚期非小细胞肺癌免疫检查点抑制剂新型生物标志物:血液PD-L1动态检测

背景免疫检查点抑制剂(immune checkpoint inhibitors,ICIs)具有良好疗效已成为恶性肿瘤治疗领域备受瞩目的翘楚。然而,仅有小部分患者获得长期临床获益。如何选择生物标志物来筛查ICIs治疗优势人群仍是一大热点。方法收集51例晚期恶性肿瘤患者的肿瘤组织和配对血样本,进行PD-L1表达的相关性分析。40例晚期非小细胞肺癌(non-small cell lung cancer,NSCLC)患者接受ICIs治疗,2个月时检测血液PD-L1(bloodPD-L1,bPD-L1)表达的动态变化,包括PD-L1 mRNA、外泌体PD-L1(exosomalPD-L1,exoPD-L1)蛋白和可溶性PD-L1(solublePD-L1,sPD-L1)。应用R软件计算最佳截断值,用于预测最佳客观缓解(best objective response,b OR)、无进展生存期(progression-free survival,PFS)和总生存期(overall survival,OS)。结果51例不同恶性肿瘤患者中,组织PD-L1(tissuePD-L1,tPD-L1)表达阳性患者的PD-L1mRNA表达水平显著升高。40例接受ICIs治疗的晚期NSCLC患者中,bPD-L1 mRNA上调≥2.04的患者b OR、PFS和OS更佳;21例接受ICIs治疗的晚期NSCLC患者中,exoPD-L1上调≥1.86的患者临床获益更大。sPD-L1动态变化与ICIs疗效无显著相关性。PD-L1 mRNA和exoPD-L1联合检测更有利于预测ICIs治疗疗效。结论bPD-L1表达与tPD-L1表达存在正相关;晚期NSCLC患者ICIs治疗初期PD-L1 mRNA和(或)exoPD-L1表达升高,可作为评估临床获益的新型生物标志物。

Silicon-integrated high-speed mode and polarization switch-andselector

On-chip optical communications are growingly aiming at multimode operation together with mode-division multiplex-ing to further increase the transmission capacity.Optical switches,which are capable of optical signals switching at the nodes,play a key role in optical networks.We demonstrate a 2×2 electro-optic Mach-Zehnder interferometer-based mode-and polar-ization-selective switch fabricated by standard complementary metal-oxide-semiconductor process.An electro optic tuner based on a PN-doped junction in one of the Mach-Zehnder interferometer arms enables dynamic switching in 11 ns.For all the channels,the overall insertion losses and inter-modal crosstalk values are below 9.03 and-15.86 dB at 1550 nm,respect-ively.

Protective effects of blueberry anthocyanin extracts on hippocampal neuron damage induced by extremely low-frequency electromagnetic field

The protective effects of blueberry anthocyanin extracts against damage induced by extremely lowfrequency electromagnetic field(ELF-EMF)were investigated in a rat model.Wistar rats were exposed to ELF-EMF with or without the administration of blueberry anthocyanin extracts(50,100,and 200 mg/kg per day intragastrically once a day)for 30 days.Blueberry anthocyanin extracts supplementation inhibited the decrease in Nissl substance levels,cell membrane integrity,and mitochondrial membrane potential induced by ELF-EMF;prevented the increase in nitric oxide,malondialdehyde,and Ca2+concentrations;suppressed superoxide dismutase and glutathione depletion;and enhanced the cognitive ability of the rats exposed to ELF-EMF.The protective effects of blueberry anthocyanin extracts against hippocampal neuron injury caused by ELF-EMF were dose-dependent.These results demonstrated that blueberry anthocyanin extracts suppress hippocampal neuron injury caused by ELF-EMF by inhibiting cell membrane damage and oxidative stress pathways,and suggested that blueberry anthocyanin treatment potentially prevents hippocampal neuron injury.

Capturability-based Fuzzy Footstep Planner for a Biped Robot with Centroidal Compliance

Compliance motion and footstep adjustment are active balance control strategies from learning human subconscious behaviors.The force estimation without direct end-actuator force measurement and the optimal footsteps based on complex analytical calculation are still challenging tasks for elementary and kid-size position-controlled robots.In this paper,an online compliant controller with Gravity Projection Observer(GPO),which can express the external force condition of perturbations by the estimated Projection of Gravity(PoG)with estimation covariance,is proposed for the realization of disturbance absorption,with which the robustness of the humanoid contact with environments can be maintained.The fuzzy footstep planner based on capturability analysis is proposed,and the Model Predictive Control(MPC)is applied to generate the desired steps.The fuzzification rules are well-designed and give the corresponding control output responding to complex and changeable external disturbances.To validate the presented methods,a series of experiments on a real humanoid robot are conducted.The results verify the effectiveness of the proposed balance control framework.

2T1C DRAM based on semiconducting MoS_(2) and semimetallic graphene for in-memory computing

In-memory computing is an alternative method to effectively accelerate the massive data-computing tasks of artificial intelligence(AI)and break the memory wall.In this work,we propose a 2T1C DRAM structure for in-memory computing.It integrates a monolayer graphene transistor,a monolayer MoS_(2)transistor,and a capacitor in a two-transistor-onecapacitor(2T1C)configuration.In this structure,the storage node is in a similar position to that of one-transistor-one-capacitor(1T1C)dynamic random-access memory(DRAM),while an additional graphene transistor is used to accomplish the nondestructive readout of the stored information.Furthermore,the ultralow leakage current of the MoS_(2)transistor enables the storage of multi-level voltages on the capacitor with a long retention time.The stored charges can effectually tune the channel conductance of the graphene transistor due to its excellent linearity so that linear analog multiplication can be realized.Because of the almost unlimited cycling endurance of DRAM,our 2T1C DRAM has great potential for in situ training and recognition,which can significantly improve the recognition accuracy of neural networks.

Architectural proteins for the formation and maintenance of the 3D genome

Eukaryotic genomes are densely packaged into hierarchical three-dimensional(3D) structures that contain information about gene regulation and many other biological processes. With the development of imaging and sequencing-based technologies, 3D genome studies have revealed that the high-order chromatin structure is composed of hierarchical levels, including chromosome territories, A/B compartments, topologically associated domains, and chromatin loops. However, how this chromatin architecture is formed and maintained is not completely clear. In this review, we introduce experimental methods to investigate the 3D genome, review major architectural proteins that regulate 3D chromatin organization in mammalian cells, such as CTCF(CCCTC-binding factor), cohesin, lamins, and transcription factors, and discuss relevant mechanisms such as phase separation.

基于二维半导体的人工神经网络芯片

近些年,二维半导体由于其独特的原子层厚度和可调控带隙等优势受到学术和产业界越来越多的关注。本文基于晶團级二维硫化钼(MoS_(2))进行了大规模电路应用尝试,成功制备了世界上第一个集乘加单元(MAC)、存储单元和激活函数电路于一体的功能性MoS:人工神经网络(ANN)芯片该芯片的制备采用了与硅基工艺更为兼容的顶栅晶体管结构,在1片晶圓级MoS_(2)薄膜上集成了818个MoS_(2)晶体管,并成功演示了基于ANN电路的触觉感知识别应用.该研究不仅展示了二维半导体在大规模集成电路中应用潜力,而且探索了二维半导体在人工智能芯片中的应用。

Stacking monolayers at will:A scalable device optimization strategy for two-dimensional semiconductors

In comparison to monolayer(1L),multilayer(ML)two-dimensional(2D)semiconducting transition metal dichalcogenides(TMDs)exhibit more application potential for electronic and optoelectronic devices due to their improved current carrying capability,higher mobility,and broader spectral response.However,the investigation of devices based on wafer-scale ML-TMDs is still restricted by the synthesis of uniform and high-quality ML films.In this work,we propose a strategy of stacking MoS_(2) monolayers via a vacuum transfer method,by which one could obtain wafer-scale high-quality MoS_(2) films with the desired number of layers at will.The optical characteristics of these stacked ML-MoS_(2) films(>2L)indicate a weak interlayer coupling.The stacked MLMoS_(2) phototransistors show improved optoelectrical performances and a broader spectral response(approximately 300-1,000 nm)than that of 1L-MoS_(2).Additionally,the dual-gate ML-MoS_(2) transistors enable enhanced electrostatic control over the stacked ML-MoS_(2) channel,and the 3L and 4L thicknesses exhibit the optimal device performances according to the turning point of the current on/off ratio and the subthreshold swing.

Albumin-based Theranostic Nanosystem for Drug Controlled Release and Magnetic Resonance Imaging Guided Therapy

Chemotherapy is still a kind of important strategy for cancer treatment,but lacking effective delivery system limits the therapeutic outcome.Owing to the excellent biocompatibility,albumin has been employed as drug vehicle;however,it has to face complicated synthesis procedures and still needs an effective technology for the drug delivery evaluation.In this study,a facile method was utilized to prepare a protein-based theranostic system through the self-assembly of albumins with small molecules and drugs;furthermore,the paramagnetic divalent manganese ions were conjugated on the surface of the nanocomposite through a coordination bond and carried out the magnetic resonance imaging.This nanosystem with a stable structure exhibited about 80 nanometer size and 7.7[Mn]mM-1S-1 T1 relaxivity;moreover,the pH-sensitive drug releasing property and the imaging function empower it with theranostic cancer therapy.Moreover,the nanocomposites effectively entered into the cancer cells and showed superior antitumor ability;and these treated cells exhibited significant T1 signal.These results suggested that the albumin-based nanosystem is a novel chemotherapy drug delivery vehicle and a promising candidate for magnetic resonance imaging.

High-precision standard enthalpy of formation for polycyclic aromatic hydrocarbons predicting from general connectivity based hierarchy with discrete correction of atomization energy

The standard enthalpy of formation is an important predictor of the reaction heat of a chemical reaction.In this work,a high-precision method was developed to calculate accurate standard enthalpies of formation for polycyclic aromatic hydrocarbons based on the general connectivity based hierarchy(CBH)with the discrete correction of atomization energy.Through a comparison with available experimental findings and other high-precision computational results,it was found that the present method can give a good description of enthalpy of formation for polycyclic aromatic hydrocarbons.Since CBH schemes can broaden the scope of application,this method can be used to investigate the energetic properties of larger polycyclic aromatic hydrocarbons to achieve a high-precision calculation at the CCSD(T)/CBS level.In addition,the energetic properties of CBH fragments can be accurately calculated and integrated into a database for future use,which will increase computational efficiency.We hope this work can give new insights into the energetic properties of larger systems.

A novel contact engineering method for transistors based on two-dimensional materials

Contact engineering is of critical importance for two-dimensional(2D)transition metal dichalcogenide(TMD)-based devices.However,there are only a few solutions to overcome this obstacle because of the complexity of the TMD-contact interface.In this work,we propose a novel method using a soft plasma treatment followed by the seamless deposition of a metal electrode to reduce the contact resistance of MoS_(2)field effect transistors(FETs).The treated FETs exhibit three times higher mobility than the control FETs without plasma treatment.The soft plasma treatment can remove the facial sulfur atoms and expose the middle Mo atoms so that they come into direct contact with the metal electrode,thus greatly improving the contact behavior.First-principles calculation is also performed to support the experimental results.Our potentially scalable strategy can be extended to the whole family of TMD based FETs to provide a possible route of device processsing technology for 2D device application.

Low-temperature combined with high-humidity thawing improves the water-holding capacity and biochemical properties of Portunus trituberculatus protein

This study compared the effects of conventional thawing methods(water immersion thawing(WIT,(25±1)℃),natural air thawing(AT,(25±1)℃,relative humidity(RH(65±2)per cent),refrigerator thawing(RT,4℃,RH(80±2)per cent)and low-temperature(LT)combined with high-humidity thawing LT,-1℃to 1℃(LT-1-1),2-4℃(LT2-4),5-7℃(LT5-7)and 8-10℃(LT8-10),RH>95 per cent)on the water-holding capacity,lipid oxidation and biochemical properties of Portunus trituberculatus(P.trituberculatus)myofibrillar protein.The results showed that WIT and AT significantly decreased the water-holding capacity while dramatically increasing lipid oxidation,protein oxidation and degeneration,resulting in serious P.trituberculatus quality deterioration.High humidity was beneficial for P.trituberculatus\.ha\A/\ng.The thawing time of P.trituberculatus under the conditions of LT2-4 was only 39.39 per cent of that of conventional air thawing at 4℃(RT),and the LT2-4 samples not only maintained better water-holding capacity but also had an obviously reduced degree of lipid oxidation,protein oxidation and denaturation.Thawed samples LT2-4 and LT5-7 provided better maintenance of P.trituberculatus quality than the LT-1-1 and LT8-10 samples.The best quality was exhibited after thawing at 2-4℃.The levels of thiobarbituric acid reacting substances,carbonyl content and surface hydrophobicity observably decreased in these samples,while the total sulfhydryl contents dramatically increased compared to those of conventionally thawed samples,indicating lower lipid oxidation and protein oxidation.Moreover,the Ca2+-ATPase activity of the sample thawed at 2-4℃(2.06 μmol Pi/mg prot/h)was markedly higher than that of samples subjected to WIT and AT.The product qualities observed after thawing at-1℃to 1℃,5-7℃and 8-10℃under LT were comparable to that observed by RT.Considering its thawing efficiency and product quality,LT is a suitable method for the thawing of P.trituberculatus,and the ideal thawing conditions were LT at 2-4℃.

Thermoplastic elastomer enhanced interface adhesion and bending durability for flexible organic solar cells

Stable interface adhesion and bending durability of flexible organic solar cells(FOSCs)is a basic requirement for its real application in wearable electronics.Unfortunately,the device performance always degraded during continuous bending.Here,we revealed the weak interface adhesion force between MoO_(3) hole transporting layer(HTL)and the organic photoactive layer was the main reason of poor bending durability.The insertion of an interface bonding layer with a thermoplastic elastomer,polystyrene-blockpoly(ethylene-ran-butylene)-block-polystyrene(SEBS)effectively improved the interface adhesion force of MoO_(3) HTL and the active layer and decreased the modulus,which ensured higher than 90%of the initial efficiency remaining after 10000 bending.Meanwhile,the FOSCs gave an efficiency of 14.18%and 16.15%for the PM6:Y6 and PM6:L8-BO devices,which was among the highest performance of FOSCs.These results demonstrated the potential of improving the mechanical durability of FOSCs through thermoplastic elastomer interface modification.

民主党派干部的选任过程:张力与调适

随着中国新型政党制度的发展,以民主党派精英为代表的党外人士进一步获得了进入体制担任实职领导岗位的机会。然而,在党管干部的原则之下,民主党派干部尽管是“非党员干部,但仍旧是党的干部”。在民主党派干部选任(即实职安排)的实践中,存在着三大张力:一是民主党派干部实职安排需求与资历能力的张力,即民主党派干部的“跨越式”选任容易产生能力不足问题;二是实职安排过程中党派间、部门间协调的张力,这导致民主党派干部在任职前后常常遭遇角色冲突,进而影响其履职效能;三是新型政党制度的成熟定型与民主党派政党制度化水平之间的张力,即民主党派本身难以承担发现与培养干部候选人的功能。如何真正提高民主党派干部选任的效能,是未来落实民主党派成员实职安排的重点之一,也从一个方面决定了我国新型政党制度的效能。

Immune checkpoint inhibitors break whose heart? Perspectives from cardio-immuno-oncology

Immune checkpoint inhibitors (ICIs) are monoclonal antibody antagonists,which can block cytotoxic T lymphocyte antigen-4 (CTLA-4),programmed death-1/ligand-1 (PD-1/PD-L1) pathways,and other molecules exploited by tumor cells to evade T cell-mediated immune response.ICIs have transformed the treatment landscape for various cancers due to their amazing efficacy.Many anti-tumor therapies,including targeted therapy,radiotherapy,and chemotherapy,combine ICIs to make the treatment more effective.However,the off-target immune activation caused by ICIs may lead to a broad spectrum of immune-related adverse events (irAEs) affecting multiple organ systems.Among irAEs,cardiotoxicity induced by ICIs,uncommon but fatal,has greatly offset survival benefits from ICIs,which is heartbreaking for both patients and clinicians.Consequently,such cardiotoxicity requires special vigilance,and it has become a common challenge both for patients and clinicians.This article reviewed the clinical manifestations and influence of cardiotoxicity from the view of patients and clinicians,elaborated on the underlying mechanisms in conjunction with animal studies,and then attempted to propose management strategies from a cardio-immuno-oncology multidisciplinary perspective.