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The receptor-binding domain of the SARS-CoV-2 spike mediates the key to binding the virus to the host receptor, but capturing the molecular signal of this spike RBD remains a formidable challenge. Here, we report a new surface-enhanced Raman spectroscopy (SERS) approach, which used gold nanoparticles prepared by low-speed constant-temperature centrifugation by bromine and calcium ions in two cleaning steps as the enhanced substrate to rapidly and accurately detect spike RBD large protein molecules in body fluids. The detection signal was extremely stable, and the orientation of the spike RBD on the enhanced substrate surface was also determined. This approach was specific in distinguishing different SARS-CoV-2 variants of spike RBD, including Delta, Beta, Gamma, and Omicron. Additionally, the enhanced substrate can identify biologically active or inactive spike RBD. This two-step cleaning enhanced substrate opens up opportunities not only for early diagnostics of SARS-CoV-2 virus but also for developing targeted drugs against viruses.

The precise self-assembly of DNA molecules can be used to create nanoprecision supramolecular materials. However, the lack of methods to characterize such supramolecular materials limits their development. Surface-enhanced Raman spectroscopy (SERS) is widely used to detect the secondary structure of simple DNA molecules, but its application in the revealing of complex DNA supramolecular information remains challenging. Herein, we proposed a modified SERS-based platform able to provide structural information on DNA supramolecular materials. The silver nanoparticle-enhanced substrate uses acetonitrile as an internal standard and modifier, and calcium ions are used as an aggregating agent to induce the formation of stable "hotspots" of silver nanoparticles, where the base planes in DNA supramolecules are perpendicular to the surface of the substrate, obtaining enhanced Raman signals of base ring in both single-stranded DNA and DNA supramolecules for the first time. The structure of DNA supramolecules was efficiently characterized using this technique, showing the great application potential of this technique in the structural analysis of nucleic acids and their ligands.

This is a constantly changing era. With the development of economic globalization, domestic and foreign enterprises are constantly facing fierce competition. The so-called “pulling the trigger and moving the whole body” refers to the chain interaction effect between the competitive behavior of enterprises and competitors, and its means are hierarchical and mutually influencing. In recent years, not only has national policies strongly supported green environmental protection, but green innovation, as an important component of an enterprise’s core competitiveness, is not only affected by the intensity of competition between both sides of the competition, but also has a catalytic effect on improving enterprise environmental performance. In the context of green transformation, enterprises have spontaneous learning behaviors, constantly learning, selecting, and accumulating competitive experience. This article discusses the key factors that affect the viability of organizations in the process of green transformation, as well as how enterprises can obtain competitive advantages in a constantly changing environment, providing useful insights for improving organizational viability.

Concessionaire selection method has drawn much attention worldwide recently. The government of Dalian has developed well-structured concessionaire selection criteria in China. This paper analyzes and summarizes experience from this concessionaire selection practice to improve procurement efficiency of regions lacking such experience or methods.

This paper gives an ontology construction model that have been used for the ship domain. After giving the way to get knowledge of semantic web and introducing the relevant definition and technology of ontology, it gives the approach of knowledge acquisition and discusses ontology-based knowledge acquisition of the Semantic Web. Finally ship domain is used as a background case study, using ontology representation to represent knowledge of the ship domain. It provides an optional and effective method for getting knowledge of ontology.

Intellectual property rights pledge has become an important financing method of some small and medium-sized enterprises but the risk and asymmetric information affect the enthusiasm of banks to participate in. As a result of intellectual property evaluation system is not perfect, government has not enough funds and so on, the existing intellectual property financing mode is hard to solve the small and medium-sized enterprise fund demand. Based on the analysis of intellectual property rights pledge financing case, from the two dimensions of the market resources and government resources, put forward an valuable proposals about enterprise, banks, intermediary institutions, insurance companies and government cooperate to solve the problem, and analyze the operation mechanism of the subject participation.

This paper gives an ontology construction model that have been used for the ship domain. After giving the way to get knowledge of semantic web and introducing the relevant definition and technology of ontology, it discusses ontologybased knowledge acquisition of the semantic web. Finally ship domain is used as a background case study, constructing a ship seed ontology and using it to acquire ship domain knowledge. It provides an effective method to gain domain knowledge.

PPP (Public-Private Partnership) is applied widely in infrastructure development and has many different models. The purpose of this research is to develop a two-stage decision-making method to select an appropriate PPP model for a specific public project. Finally, effectiveness of the two-stage decision-making method has been verified through a case study.

SMEs in the incubation are the main innovation of a nation, and the new product is not without SMEs technology innovation. It is not only the theoretical but also practical significance that SMEs in the Incubation develop strongly for economic growth and technology innovation, but as the normal SMEs, they also face the financial support difficulty or more others. This paper analyses the financial demand characters of SMEs in the incubation based on the theory of business life cycle. The conclusion is that different development phases need different financial support because SMEs in the incubation face different financial cycles. The financial support system is set up to fit the cycle needs of SMEs in the incubation, and then the suggestions are illustrated. The results can be the reference for the problems of financial support for SMEs in the incubation.

Management in our country faces strong challenges at the turn of the century. By analyzing the hotspots disturbed in Chinese management field, a new idea is proposed in this paper. This idea showed that it is necessary to build a management theory to accommodate the requirements of times dynamically. Recognizing the effect of management, choosing the adequate management model, measuring the performance of administration and surveying the contribution of management in economic growth are also included. Meanwhile, the considerations and ways are given.

Location-routing problem is a kind of hard combinatorial optimization problem that arose in supply chain and logistic system. A genetic algorithm was designed to solve the problem. Novel genetic representation and corresponding genetic operations were used in the genetic algorithm so that the location-allocation and vehicle-routing can be tackled simultaneously. Computer simulation shows that the proposed algorithm is effective