Research status, hot spots, difficulties and future development direction of microbial geoengineering

Microbial geoengineering technology,as a new eco-friendly rock and soil improvement and reinforcement technology,has a wide application prospect.However,this technology still has many deficiencies and is difficult to achieve efficient curing,which has become the bottleneck of large-scale field application.This paper reviews the research status,hot spots,difficulties and future development direction microbial induced calcium carbonate precipitation(MICP)technology.The principle of solidification and the physical and mechanical properties of improved rock and soil are systematically summarized.The solidification efficiency is mainly affected by the reactant itself and the external environment.At present,the MICP technology has been preliminarily applied in the fields of soil solidification,crack repair,anti-seepage treatment,pollution repair and microbial cement.However,the technology is currently mainly limited to the laboratory level due to the difficulty of homogeneous mineralization,uneconomical reactants,short microbial activity period and large environmental interference,incidental toxicity of metabolites and poor field application.Future directions include improving the uniformity of mineralization by improving grouting methods,improving urease persistence by improving urease activity,and improving the adaptability of bacteria to the environment by optimizing bacterial species.Finally,the authors point out the economic advantages of combining soybean peptone,soybean meal and cottonseed as carbon source with phosphogypsum as calcium source to induce CaCO3.

Observations of intracellular second-harmonic generation imaging in black phosphorus nanosheets

Functionalized black phosphorus(BP)nanosheets have been considered as promising nanoagents in cancer therapy due to their excellent photothermal conversion efficiency.However,it is still difficult to visually monitor the dynamic localization of BP nanoagents in cancer cells.In this paper,we systematically studied the second-harmonic generation(SHG)signals originating from exfoliated BP nanosheets.Interestingly,under the excitation of a high frequency pulsed laser at 950 nm,the SHG signals of BP nanosheets in vitro are almost undetectable because of their poor stability.However,the intracellular SHG signals from BP nanosheets could be measured by in vivo optical imaging due to the efficient enrichment of living HeLa cells.Moreover,the SHG signal intensity from BP nanosheets increases with the prolonged incubation time.It can be expected that the BP nanosheets could be a promising intracellular SHG nanoprobe employed for visually in vivo biomedical imaging in practical cancer photothermal therapy(PIT).

RIOK1 synergizes with TRIP13 by regulating the E2F-Rb signaling pathway to promote the proliferation of esophageal cancer cells

Esophageal cancer is one of the leading causes of cancer death in the world,with approximately half of the new cases occurring in China every year.^(1)Esophageal squamous cell carcinoma(ESCC)is the main subtype,accounting for more than 90%,and the five-year survival rate is less than 10%.Using large-scale genome analysis,many driver mutations and key pathways associated with ESCC have been identified.However,these genomic signatures have not improved the clinical management of EscC patients,or established effective targeted therapy.^(2)Esophageal cancer still lacks representative molecular markers.

Liquid metal droplet dynamics

The unique properties to combine the dual merits of both liquids and metals together make the gallium‐based liquid metal(LM)droplets a class of unconventional substitute which possess great potential for a group of newly emerging areas,such as stretchable electronics,soft devices,micro sensors and actuators.In addition,LM droplets are undoubtedly an intriguing target worth of pursuing in fundamental hydrodynamic investigations due to their extremely high surface tension nature compared to classical nonmetallic fluids.Since the discovery of the diverse transformation phenomena and self‐fueled droplet mollusks of LM that can move automatically in solution via single electricity or even without any external energy supply,tremendous attentions were attracted to this special fluidic object of LM droplets.Over the past decade,there has been a proliferation of explorations on LM droplet dynamics,while the involved contents are heterogeneous due to the interfacial physical/chemical activity of the LM and the diversity of the kinetic behaviors.To better understand and manipulate the droplet behavior and to promote further development of the LMs,this review is dedicated to summarize the latest progress and presents an overview on basic findings related to LM macrodroplet dynamics.Firstly,the extended definition of LM droplets and the corresponding fabrication methods are given.Then,typical works on LM droplet dynamics are systematically interpreted based on their different behavior categories.Finally,the perspectives,main obstacles and challenges restricting the development of LM droplet dynamics are pointed out.

环境友好型材料增韧改性聚乳酸研究进展

生物基热塑性聚乳酸(PLA)具有高强度、高模量和良好的生物降解性和生物相容性,有望取代部分传统的石油基聚合物.然而,PLA固有的脆性、低热变形温度和相对较高的成本阻碍了其广泛应用.本文简述了聚合物的增韧机理,综述了近年来采用可降解聚酯、生物基弹性体、天然高分子及其衍生物、纳米材料以及目前市售抗冲改性剂等环境友好型材料增韧改性聚乳酸的研究进展.提出了从分子结构设计出发制备出不以牺牲PLA强度为代价,又能提高其韧性的环境友好型材料.该材料与聚乳酸既有较好的界面黏接强度,又能在复合材料发生冲击断裂时引发基体产生空穴-银纹来吸收与转移冲击能.此外,在提高基体韧性的同时还应考虑提高PLA的结晶速率及其结晶度,从而提高复合材料的热变形温度.

Systems approaches to urban underground space planning and management-A review

The necessity to recognize the subsurface or underground and all its current and potential uses as part of our urban environment,to integrate this into urban planning and governance,and to foster conscious allocation of subsurface space has been increasingly recognized over the last century.At the same time,systems thinking as a‘buzz-word’has gained relevance for approaching complex problem areas in all kinds of disciplines including those preoccupied with the subsurface.This paper reviews the literature about urban underground planning through a systems-lens.To set this in context,it is outlined how organizational principles for the urban subsurface have evolved,and the main aspects of systems thinking are introduced followed by a discussion of how this thinking could be applied to the urban underground.Strategies and tools presented in the recent literature in the field are then reviewed based on this perspective,asking how systemic the proposed strategies and tools are when the local geology,as well as legal and institutional settings are accepted as a baseline for analysis or intervention.Systemic approaches built on this premise have the potential to capture existing and evolving complexities,foster a better understanding of the value of subsurface space for a city and ultimately enable an efficient and fair allocation of underground space.However,propositions for holistic solutions remain dispersed,interventions often remain based in an engineering mindset,and a shift in mind-set remains a challenge.More research in collaboration with local and regional administrations or authorities based on systems thinking frameworks could help to facilitate this shift.