Non-invasive assessment for intratumoural distribution of interstitial fluid flow

Interstitial fluid plays a vital role in drug delivery and tumour treatment.However,few non-invasive measurement methods are available for measuring low-velocity biological fluid flow.Therefore,this study aimed to develop a novel technology called interstitial flow velocity-MRI.The interstitial flow velocity-MRI sequence consists of a dual inversion recovery preparation and an improved stimulated echo sequence(ISTE)combined with phase-contrast MRI.A homemade flow phantom was used to assess the feasibility and sensitivity of interstitial flow velocity-MRI.In addition,xenografts of female BALB/c mouse models of 4T1 breast cancer administered losartan(40 mg/kg)or saline(n?6)were subjected to imaging on a 7.0 T scanner to assess the in vivo interstitial fluid flow velocity.The results showed a significant correlation(P<0.001)between the theoretical velocities and velocities measured using the flow phantom.Interstitial flow velocity-MRI could detect a velocity as low as 10.21±2.65 mm/s with a spatial resolution of 0.313 mm.The losartan group had a lower mean interstitial fluid velocity than the control group(85±16 vs 113±24 mm/s).In addition,compared to the saline treatment,losartan treatment reduced the proportion of collagen fibres by 10%and 12%in the Masson and Sirius red staining groups,respectively.Interstitial flow velocity-MRI has the potential to determine interstitial fluid flow velocity non-invasively and exhibits an intuitive velocity map.

Experimental Research of Dynamic Response of Laser-Induced Film-Substrate System

Film-substrate’s interfacial bonding strength is closely related to film quality. An excellent interfacial bonding strength is the premise for the well use of film. The laser detecting technique of discrete scratches based on laser shockwave effect is a new method, which can measure interfacial bonding strength. With this technique, film-substrate system is of transient load of different laser energy, the relation between the dynamic response characteristics of such film-substrate system and film-substrate’s interfacial bonding strength is a core problem to be solved urgently. On this basis, this paper conducted research on the dynamic response characteristics of film-substrate system during laser loading process using detecting technique of PVDF patch sensor. Results show that under the irradiation of different laser energy, it can detect dynamic responses of theory models of different film-substrate system using PVDF patch sensor, wherein shockwave dynamic response and dynamic strain response are included. Laser energy and interfacial bonding strength are of a regular influence to the dynamic response of film-substrate system theory model.

大数据技术在智慧交通中的应用新模式

互联网的广泛应用和大数据技术的快速发展给各行各业都带来了巨大的冲击和改变,在城市交通方面也不例外。交通行业面对此次的冲击和挑战不可避免地进行了改变,主动且积极地融入了大数据时代,形成了智慧交通的服务模式。本文将对于智慧交通是如何融入大数据时代以及它在大数据中的实际应用进行分析,并对智慧交通如何利用大数据进行下一步的更新升级进行讨论,最后会结合现在人们的需求和大数据技术在现实中所存在的困难提出一些建议。

有机反离子十六烷基三甲基铵的表面活性及应用性能

研究了十六烷基三甲基甲酸铵(HTAF)、十六烷基三甲基乙酸铵(HTAA)和十六烷基三甲基丁酸铵(HTAE)的表面活性、抗静电性、耐盐和耐酸碱性、金属腐蚀性、抑菌性和生物降解性,并对HTAF与脂肪醇聚氧乙烯醚硫酸钠(AES)、脂肪醇聚氧乙烯醚羧酸钠(AEC-9Na)和非离子表面活性剂烷基糖苷(APG_(1214))二元复配体系的抑菌性和去污洗涤效果进行了测试。结果表明:HTAE的临界胶束浓度(cmc)和表面张力(γ_(cmc))皆低于HTAF和HTAA;HTAF和HTAA的抗静电性能与传统抗静电剂十八烷基二甲基羟乙基硝酸铵(SN)处于一个数量级,HTAE的抗静电性较差;三种有机反离子季铵盐对一价Na^(+)和二价Ca^(2+),Mg^(2+)都具有优良的耐盐性(>200 g/L),并且耐酸碱性能较好;有机反离子季铵盐对金属的腐蚀性明显低于十六烷基三甲基氯化铵(HTAC);三种有机反离子季铵盐的7天初级生物降解度都大于98%;在20 mg/kg含量下,HTAF对金黄色葡萄球菌(S.aureus)和大肠杆菌(E.coli)仍表现出较好的抑菌效果(>95%)。二元复配体系表明:AES/HTAF混合体系相比标准洗衣液具有更好的去污效果,但基本无抑菌性能;AEC-9Na/HTAF混合体系兼具优异的抑菌和去污洗涤性能;APG;/HTAF混合体系抑菌性能较好,但去污效果较差。

Model-based offline reinforcement learning framework for optimizing tunnel boring machine operation

Research on automation and intelligent operation of tunnel boring machine(TBM)is receiving more and more attention,benefiting from the increasing construction data.However,most studies on TBM operations optimization were trained by the labels of human drivers’decisions,which were subjective and stochastic.As a result,the control parameters suggested by these models could hardly surpass the performance of a human driver,even the possibility of subjective incorrect decisions.Considering that the geomechanical feedback to TBM under drivers’actions is objective,in this paper,a transformer-based model called the geological response for tunnel boring machine(GRTBM),is proposed to learn the relationship between operation-adjust and TBM monitoring changes.Additionally,with the model-based offline reinforcement learning,this paper provided a novel approach to optimizing the TBM excavation operations.The decision processes,recorded in the Yin-song TBM project for a waterway tunnel in Jilin Province of China,were used for the validation of the model.By adopting an implicit perception of geological conditions in the GRTBM model,the suggested method achieved the desired state within a single action,greatly outperformed the practical adjustments where 500 s were taken,revealing the fact that the proposed model has the potential to surpass the capability of human beings.

Flow behavior of liquid metal in the connected fascial space： Intervaginal space injection in the rat wrist and mice with tumor

The fascia and the fascial space can help provide a better understanding of the body. An intervaginal space injection （ISI） provides unique advantages that require further investigation. An upper limb model including physiological conditions and the tumor process was chosen to determine the flow behavior of liquid metal after ISI. In normal rats, after the injection of liquid metal into the intervaginal space comprising tendons, vessels, and nerves, magnetic resonance imaging and an anatomy experiment indicated that the liquid metal wrapped around the fascial space and finally reached the fingertip downstream and the armpit upstream in addition to the neurovascular bundle without vessels or lymph nodes. Using environmental scanning electron microscopy （ESEM） images, we discovered that the liquid metal was wrapped around the fibers of the fascia and moved forward in microscale or nanoscale areas. These data confirmed a fascia-based pathway. In tumors, the liquid metal moved to the tumor capsule through the damaged spot, where cancer cells destroy the integrity of the fascia between the normal cells and cancer cells. The liquid metal partly wrapped around the tumor and separated the tumor from the surrounding normal muscle. The ESEM images showed that fibers of the fascia penetrated the tumor, thus forming a network through which the liquid metal penetrated the tumor. Our study illustrated the physiological and pathological flow behavior of liquid metal in the upper limb after ISI and demonstrated a nonvascular pathway in the fascia. ISI may be useful for clinical treatment in the fascial pathway.

Special interstitial route can transport nanoparticles to the brain bypassing the blood-brain barrier

Nowadays,nanoparticles(NPs)are considered to be ideal tools for bioimaging and drug delivery.Although increasing research has focused on NP biodistribution,transportation in the interstitial architecture has been neglected.The entire body is connected by the interstitial architecture,which can provide a long-range and direct pathway for NP biodistribution in a nonvascular system.In this study,we report that 10-nm gold NPs injected directly into the interstitial architecture of the tarsal tunnel of rats(intervaginal space injection(ISI))were delivered to the brain without crossing the blood-brain barrier.Furthermore,NaGdF4 nanoparticles were used to explore the transportation route by magnetic resonance imaging.The results demonstrated that,after ISI,the NaGdF4 nanoparticles were transported through the perivascular interstitial space of the carotid arteries and brain vessels to the brain.This is a special nonvascular transportation route like a stream based on the interstitial architecture that provides an alternative pathway for NP biodistribution.