Tianwen-1 and China's Mars exploration program

About every 26 months, the distance between Earth and Mars reaches a minimum, and that is the best time window for Mars exploration from Earth. In July 2020, three spacecraft started their journey to Mars: the Hope orbiter of the United Arab Emirates, the Tianwen-1 mission of China and the Perseverance rover of the United States’ National Aeronautics and Space Administration (NASA). If all go well, these spacecraft will reach Martian orbit in February 2021 and start their scientific observations.Tianwen-1 is China''s first mission to Mars. It includes an orbiter, a lander and a rover. It carries 13 scientific payloads and will investigate the topography, soil composition, water-ice distribution, internal structure, atmospheric environment and physical fields (electromagnetic and gravitational) of Mars. In this interview, we talked with the mission''s Chief Scientist Yongxin Pan (潘永信) and Scientific Payload Sub-System Director Chi Wang (王赤) about this scientific mission and China''s future plans for Mars exploration.     

Visually constructing the chemical structure of a single molecule by scanning Raman picoscopy

The strong spatial confinement of a nanocavity plasmonic field has made it possible to visualize the inner structure of a single molecule and even to distinguish its vibrational modes in real space. With such ever-improved spatial resolution, it is anticipated that full vibrational imaging of a molecule could be achieved to reveal molecular structural details. Here we demonstrate full Raman images of individual vibrational modes at the ångström level for a single Mg-porphine molecule, revealing distinct characteristics of each vibrational mode in real space. Furthermore, by exploiting the underlying interference effect and Raman fingerprint database, we propose a new methodology for structural determination, which we have called ‘scanning Raman picoscopy’, to show how such ultrahigh-resolution spectromicroscopic vibrational images can be used to visually assemble the chemical structure of a single molecule through a simple Lego-like building process.     

Innovation as co-evolution of scientific and technological networks: exploring tissue engineering

The question of exactly how science is commercialized is an important one. While the social structures of “science” and “technology” are distinctive, recent work suggests that scientific and technological ideas in fact co-evolve. This paper addresses the dynamics of such co-evolution: are scientific networks deeply co-mingled with networks through which technology is created and if so how? It does so in a study of an emerging area of biomedicine—tissue engineering. The research is based on a novel methodology that takes advantage of the fact that an idea is often inscribed in both a patent and paper, thus forming a patent–paper pair. Starting with the pair, it is possible to trace the citation network of patents, papers, inventors and authors, combining traditional bibliometric analysis with in-depth interviews to provide new insights. The results show that for this case there exist distinctive scientific and technological networks. Furthermore, while there is evidence of overlap, it is neither co-publishing nor citation as might be predicted from current literature. Rather co-mingling exists through founding, licensing, consulting and advising. This has implications for our understanding of the processes through which spillovers arise, the way in which commercialization and technology transfer should be structured and for recent debates on conflict of interest in biomedicine.     

Stable low-fouling plasma polymer coatings on polydimethylsiloxane

Polydimethylsiloxane (DMS) is a popular material for microfluidics, but it is hydrophobic and is prone to non-specific protein adsorption. In this study, we explore methods for producing stable, protein resistant, tetraglyme plasma polymer coatings on PDMS by combining extended baking processes with multiple plasma polymer coating steps. We demonstrate that by using this approach, it is possible to produce a plasma polymer coatings that resist protein adsorption (<10 ng/cm²) and are stable to storage over at least 100 days. This methodology can translate to any plasma polymer system, enabling the introduction of a wide range of surface functionalities on PDMS surfaces.     

论情报学元理论的“3C”主义

引入了元理论的概念,论述3个基本的情报学元理论——建构主义、集体主义和结构主义,讨论＂3C＂主义与情报学元理论的关系。     

Information processing,evaluation, and utilization: The role of academic libraries in research and development (R & D) in Zambia

The study attempts to apply J.R. Bettman's consumer choice theory to the concept of information processing, evaluation and utilization within the present and future Zambian context. Central to this is the belief that information is a marketable commodity and is one that is critically essential in all activities relating to research and development (R & D) in Zambia. However, the author argues that unless there are discernible changes in the traditional attitudes and cultural values among Zambians, information processed and organized by academic libraries in Zambia will never be fully utilized even in research and development activities.     

Do ‘liberal market economies’ really innovate more radically than ‘coordinated market economies’?: Hall and Soskice reconsidered

In Varieties of Capitalism; The Institutional Foundations of Comparative Advantage, Peter A. Hall and David Soskice (H&S) argue that technological specialization patterns are largely determined by the prevailing “variety of capitalism”. They hypothesize that “liberal market economies” (LMEs) specialize in radical innovation, while “coordinated market economies” (CMEs) focus more on incremental innovation. Mark Zachary Taylor [Taylor, M.Z., 2004. Empirical evidence against varieties of capitalism's theory of technological innovation. International Organization 58, 601-631.] convincingly argued that Hall and Soskice's empirical test is fundamentally flawed and proposed a more appropriate test of their conjecture. He rejected the varieties of capitalism explanation of innovation patterns. We extend and refine Taylor's analysis, using a broader set of radicality indicators and making industry-level comparisons. Our results indicate that Hall and Soskice's conjecture cannot be upheld as a general rule, but that it survives closer scrutiny for a substantial number of industries and an important dimension of radicality.     

Technological change in the Norwegian whaling industry: A case-study in the use of patent-statistics as a technology indicator

This paper presents an example of the use of patent statistics as a technology indicator in one industry. The first part deals with the problem of interpretation. Through examination of several other partial technology indicators, it is concluded that at least in this industry, patent statistics provide a reliable indicator, not only for the timing of inventions, but for the timing of innovations and diffusion as well. The reason is that the intervals between the stages in the innovation process are very short. This contradicts evidence from many other industries, and it is therefore emphasized that generalizations are unwarranted.The second part of this paper deals with the possible causes of technological change in Norwegian whaling. The methodology is inspired by J. Schmookler's work. Thus, the patents are correlated with other indicators of economic development in the industry. But while Schmookler's view is that the patent activity is determined by social demand and economic growth, the conclusions for the Norwegian whaling industry point in the opposite direction: the technological transformation that took place during the 1920s and early 1930s was forced upon the firms in their efforts to cut costs, which was achieved by rationalizing production and catching methods in line with a downward price trend for whale oil.     

情报学的元理论探析

本文分析并界定了元理论的概念,对情报学元理论研究的发展脉络和现状进行了研究,提出了情报学元理论-理论的层次模型.     

What drives the formation of ‘valuable’ university–industry linkages?: Insights from the wine industry

Most of the literature on university–industry (U–I) linkages assumes that these linkages are beneficial per se. We question this assumption, suggesting that not all such linkages are equally helpful. In this paper, we explore the factors driving the formation of ‘valuable U–I linkages’, conceived as those linkages between universities and firms that have a higher potential to diffuse knowledge to other firms in their regional economy. Our empirical strategy combines case-study methodology with econometric techniques using data from two wine clusters in Chile and in Italy. The firm's knowledge base is found to be a key driver of ‘valuable’ U–I linkages. We conclude that selectivity should be encouraged among policy makers endeavouring to promote U–I linkages.     

Precision spectroscopy of atomic helium

Helium is a prototype three-body system and has long been a model system for developing quantum mechanics theory and computational methods. The fine-structure splitting in the 2³P state of helium is considered to be the most suitable for determining the fine-structure constant α in atoms. After more than 50 years of efforts by many theorists and experimentalists, we are now working toward a determination of α with an accuracy of a few parts per billion, which can be compared to the results obtained by entirely different methods to verify the self-consistency of quantum electrodynamics. Moreover, the precision spectroscopy of helium allows determination of the nuclear charge radius, and it is expected to help resolve the ‘proton radius puzzle’. In this review, we introduce the latest developments in the precision spectroscopy of the helium atom, especially the discrepancies among theoretical and experimental results, and give an outlook on future progress.     

The content of productivity growth in Swedish manufacturing

It is hardly surprising that the slowdown in economic growth throughout the industrial world in the last decade has attracteda lot of attention by economists. The decline in productivity growth has been a special object of study. However, the causes of this decline still largely remain a mystery. In the present paper it is suggested that a more micro-based approach to the problem than the conventional macro-oriented growth accounting method yields additional insights. A methodology is outlined which can at least complement the conventional approach and which is specially designed to open the way for micro analysis of productivity change without losing sight of the macro side. This is done by first breaking down total factor productivity growth through disaggregation to lower and lower levels of observation in order to separate out structural from “purely technical” changes. Then framework is presented for analyzing how productivity changes at the micro level can be aggregated to the macro level. The results emphasize the importance of economies of scale and resource allocation.     

Key website factors in e-business strategy

The design of a quality website, as part of e-business strategy, has become a key element for success in the online market. This article analyzes the main factors that must be taken into account when designing a commercial website, concentrating on the Aceros de Hispania company and its business model. We have studied the features which determine website quality: accessibility, speed, navigability, content, and we have calculated the Web Assessment Index (WAI) proposed by Miranda and Bañegil [Miranda, F. J., & Bañegil, T. M. (2004). Quantitative evaluation of commercial websites: An empirical study of Spanish firms. International Journal of Information Management, 24(4), 313–328]. The results obtained provide several lessons which should be borne in mind when designing a commercial e-strategy. Firstly, it can be observed that Internet popularity and search engine positioning facilitate entry to practically inaccessible markets. Secondly, the navigability makes users feel comfortable and secure when browsing it, which increases the probability of a transaction being completed. Finally, the information provided on the website must be accurate, informative, updated and relevant to customers’ requirements. Like Aceros de Hispania, any company, thanks to the Internet, will be able to overcome the barriers which would impede its successful worldwide development in the offline market.     

“双积分”政策对新能源车企研发投入的影响分析

（中南大学商学院，长沙 410083） 摘 要：“双积分”政策实施的目的在于构建促进新能源车企研发创新的长效机制。以我国新能源汽车（整车）上市公司作为研究样本，在考虑企业异质性的基础上，应用双重差分模型分析了“双积分”政策从酝酿到实施背景下新能源车企研发投入的规模、强度和结构三个维度的变化。研究结果表明：“双积分”政策在“酝酿期”，便对新能源车企“提前释放”出了积极作用；“双积分”政策显著促进了新能源车企的研发投入，研发投入规模相比强度增长更明显，在研发投入结构上表现为“重资本、轻人才”；新能源车企的异质性对于“双积分”政策实施效果存在调节性影响，“乘用车”车企的政策激励作用相对更显著，企业规模、盈利能力等对于政策激励效果有着正向调节作用。我国新能源汽车产业政策的优化调整要高度重视政策“酝酿期”在引导相关生产企业提前布局“主动性”中的积极作用，“双积分”政策要以促进新能源车企提高研发投入强度并优化研发投入结构作为重点，对于不同类型、不同发展水平的新能源车企实行分类引导，构建公平统一并体现差异化特色的政策体系。     

Information theory of metasurfaces

We propose a theory to characterize the information and information processing abilities of metasurfaces, and demonstrate the relation between the information of the metasurface and its radiation pattern in the far-field region. By incorporating a general aperture model with uncertainty relation in L²-space, we propose a theory to predict the upper bound of information contained in the radiation pattern of a metasurface, and reveal the theoretical upper limit of orthogonal radiation states. The proposed theory also provides guidance for inverse design of the metasurface with respect to given functionalities. Through investigation of the information of disordered-phase modulated metasurfaces, we find the information invariance (1−γ, where γ is Euler''s constant) of chaotic radiation patterns. That is to say, the information of the disordered-phase modulated radiation patterns is always equal to 1−γ, regardless of variations in size, the number of elements and the phase pattern of metasurface. This value might be the lower bound of radiation-pattern information of the metasurface, which can provide a theoretical limit for information modulation applications, including computational imaging, stealth technologies and wireless communications.     

Gene regulatory network stabilized by pervasive weak repressions: microRNA functions revealed by the May–Wigner theory

Food web and gene regulatory networks (GRNs) are large biological networks, both of which can be analyzed using the May–Wigner theory. According to the theory, networks as large as mammalian GRNs would require dedicated gene products for stabilization. We propose that microRNAs (miRNAs) are those products. More than 30% of genes are repressed by miRNAs, but most repressions are too weak to have a phenotypic consequence. The theory shows that (i) weak repressions cumulatively enhance the stability of GRNs, and (ii) broad and weak repressions confer greater stability than a few strong ones. Hence, the diffuse actions of miRNAs in mammalian cells appear to function mainly in stabilizing GRNs. The postulated link between mRNA repression and GRN stability can be seen in a different light in yeast, which do not have miRNAs. Yeast cells rely on non-specific RNA nucleases to strongly degrade mRNAs for GRN stability. The strategy is suited to GRNs of small and rapidly dividing yeast cells, but not the larger mammalian cells. In conclusion, the May–Wigner theory, supplanting the analysis of small motifs, provides a mathematical solution to GRN stability, thus linking miRNAs explicitly to ‘developmental canalization’.     

Graphdiyne-based metal atomic catalysts for synthesizing ammonia

Development of novel catalysts for nitrogen reduction at ambient pressures and temperatures with ultrahigh ammonia (NH₃) yield and selectivity is challenging. In this work, an atomic catalyst with separated Pd atoms on graphdiyne (Pd-GDY) was synthesized, which shows fascinating electrocatalytic properties for nitrogen reduction. The catalyst has the highest average NH₃ yield of 4.45 ± 0.30 mg_NH3 mg_Pd⁻¹ h⁻¹, almost tens of orders larger than for previously reported catalysts, and 100% reaction selectivity in neutral media. Pd-GDY exhibits almost no decreases in NH₃ yield and Faradaic efficiency. Density functional theory calculations show that the reaction pathway prefers to perform at the (Pd, C1, C2) active area because of the strongly coupled (Pd, C1, C2), which elevates the selectivity via enhanced electron transfer. By adjusting the p–d coupling accurately, reduction of self-activated nitrogen is promoted by anchoring atom selection, and side effects are minimized.     

Integrated dynamic wet spinning of core-sheath hydrogel fibers for optical-to-brain/tissue communications

Hydrogel optical light-guides have received substantial interest for applications such as deep-tissue biosensors, optogenetic stimulation and photomedicine due to their biocompatibility, (micro)structure control and tissue-like Young''s modulus. However, despite recent developments, large-scale fabrication with a continuous synthetic methodology, which could produce core-sheath hydrogel fibers with the desired optical and mechanical properties suitable for deep-tissue applications, has yet to be achieved. In this study, we report a versatile concept of integrated light-triggered dynamic wet spinning capable of continuously producing core-sheath hydrogel optical fibers with tunable fiber diameters, and mechanical and optical propagation properties. Furthermore, this concept also exhibited versatility for various kinds of core-sheath functional fibers. The wet spinning synthetic procedure and fabrication process were optimized with the rational design of the core/sheath material interface compatibility [core = poly(ethylene glycol diacrylate-co-acrylamide); sheath = Ca-alginate], optical transparency, refractive index and spinning solution viscosity. The resulting hydrogel optical fibers exhibited desirable low optical attenuation (0.18 ± 0.01 dB cm⁻¹ with 650 nm laser light), excellent biocompatibility and tissue-like Young''s modulus (<2.60 MPa). The optical waveguide hydrogel fibers were successfully employed for deep-tissue cancer therapy and brain optogenetic stimulation, confirming that they could serve as an efficient versatile tool for diverse deep-tissue therapy and brain optogenetic applications.     

Calculating the information content of an information process for a domain expert using Shannon''s mathematical theory of communication: A preliminary analysis

The problem addressed in this article is to use Bertram Brookes' ‘fundamental equation’ as a starting off-point for a conceptual exercise whose purpose is to set out a method for calculating the information content of an information process. The knowledge structure variables in the Brookes' equation are first operationalized, following principles set out in Claude Shannon's mathematical theory of communication. The set of ‘a priori’ alternatives and the a priori probabilities assigned to each member of the set by the person undergoing the information process is the operational definition of the variable ‘K[S]’ from the ‘fundamental equation,’ which represent the person's knowledge structure ‘before’ the information process takes place. The set of ‘a posteriori’ alternatives and the revised probabilities assigned to each member of the set by the person undergoing the information process is the operational definition of the Brookes' variable ‘K[S + ΔS],’ which is the person's knowledge structure ‘after’ the information process takes place. To illustrate how the variables can be determined, an example of a information process is used from a recent real-life archeological discovery.