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The purpose of this paper is to adopt rapid prototyping (RP) technology to fabricate self‐hardening calcium phosphate composite (CPC) scaffolds with a controlled internal channel network to facilitate nutrient supplying and cell growth using RP technique and investigate their in vitro performance.

Porous scaffolds should possess branched channels to ensure uniform cell feeding and even flow of culture medium to promote uniform cell attachment and growth. A new three dimensional (3D) flow channel structure has been designed based on conversation of energy and flow. The CPC scaffold possessing such a channel network was made by indirect solid free form fabrication. Negative model of scaffold was designed by Pro/E software and its epoxy resin mold was fabricated on a sterolithography apparatus and the CPC slurry was filled in these molds. After CPC was self hardened, the mold was baked. The mold was removed by pyrolysis and then the designed scaffold was obtained.

The sizes of the fabricated scaffolds were consistent with the designed. The average compressive strength of the scaffold is approximately 6.0 MPa. Computational fluid dynamics and perfusion culture results showed that such a 3D flow channel arrangement would lead to a more uniform distribution of flow and cells and good transportation of nutrients.

The size errors of fabricated scaffolds could not escape and perfusion methods were difficult to control.

The basic design concept presented showed great promise for use in bone tissue engineering and fabrication method enhanced the versatility of scaffold fabrication. The designed scaffold structure made it possible to keep integrality of the scaffold when direct observation cells inside the channel by scanning electron microscopy (SEM).

The purpose of this study was to investigate the tribological properties of bulk Fe₂B with pre-oxidation treatment.

Bulk Fe₂B was oxidized in an electric box furnace with a soaking time of 9 min under 750°C in air. Then, the tribological experiments were carried out on an UMT-Tribolab tester.

The oxide layer was composed of Fe, Fe₂O₃, Fe₃O₄, B₂O₃ and H₃BO₃. The oxidative direction of bulk Fe₂B was perpendicular to the sample surface. But, the oxidative direction of Fe₂B crystals was irregular. At 0.1 m/s, the friction coefficient was the lowest. The effects of shortening the running-in period of friction and reducing the friction coefficient by pre-oxidation treatment at 0.1 m/s were remarkable. Nevertheless, the effect of pre-oxidation treatment was futile at 0.2 m/s. Wear mechanisms of oxidized Fe₂B mainly were adhesive and abrasive wear.

The effects of shortening the running-in period of friction and reducing the friction coefficient by pre-oxidation treatment were remarkable.

Integrating transaction costs economics and task-technology fit theory, this study distinguishes two categories of social media–enabled interactions, namely task-related interactions and tie-related interactions, and explores the match between these two and firms' use of contracts in achieving safeguarding and coordinating purposes in interfirm governance.

Two studies were conducted to test the hypotheses. In Study 1, this study collaborated with a professional market research firm and collected responses from Chinese manufacturing firms in a survey. In Study 2, this study designed a scenario-based experiment and collected 239 participants from the Credamo platform.

This study categorized social media–enabled interactions into task-related interactions and tie-related interactions and conducted two studies to reveal that the safeguarding purpose of contract specificity is amplified by tie-related interactions, whereas the coordinating purpose of contract specificity is strengthened by task-related interactions.

This study assumes that firms permit and encourage the use of social media. However, some firms might prohibit the use of social media due to risk issues, or their partners may be prohibited from using social media.

Given that social media–enabled interactions have joint effects with contracts in achieving safeguarding and coordinating purposes, a firm's employees should match their goals with an appropriate type of social media–enabled interactions.

This study enriches the interfirm governance literature by uncovering the roles of these two types of interactions in matching contract specificity to achieve safeguarding and coordinating purposes, which provides actionable insights for managers in governing interfirm relationships.

China's defense industry is analyzed by comparing the technical level of the military and civilian products manufactured by China's nuclear, space, aviation, shipbuilding, ordnance, and electronics industries with their advanced counterparts. Generally, China's defense industry is about 20 years behind the global leaders. Thus, it is inappropriate to declare China's emergence as the world’s second military power. However, if it continues on its current development trajectory, it will attain that status in the near future.

As the essential requirement of socialism with Chinese characteristics, common prosperity stands for both the goal of and the approach to economic growth. Shared development is a new stage of the process of common prosperity. From the perspective of economic growth, it requires the low- and middle-income groups to gain more from the growth than high-income groups. The paper aims to discuss these issues.

Based on provincial panel data, the random effect model and the dynamic panel model are used in this paper to analyze the path to achieve pro-poor growth.

The keys to achieve pro-poor growth are first to promote new urbanization with people at the center, diversify the forms of employment and improve the income structure of the residents, and second to improve the accuracy in designing redistribution policies.

After the realization of “some get rich first” policy, it is important to swiftly adapt to a new mindset of shared development, which charters a new course to the Marxist common prosperity. There exist few established economic theories or action plans with respect to shared development. Pro-poor growth, however, offers a perspective to achieve both sharing and development.

With the development of social economy, the urbanization of the world has presented a new development trend. The green, ecological, and economic city has gradually attracted people's attention. How to plan new cities and towns to coordinate economic development with nature has been the focus of domestic and foreign scholars. Based on this premise, this article elaborates the domestic and foreign research status of ecological city and puts forward a new type of green ecological civilization from the perspective of evolution of civilization. From the perspective of green ecological economy, the evolution of China's urban planning is studied in terms of the urban and rural areas, nature, pollution, industry, culture, and other aspects. To accumulate experience, green ecological planning in New York is also analyzed at multiple levels, such as urban expansion, energy, and urban water use. According to the development of our country in the past 30 years, the development strategy of urbanization suitable to China's national conditions is introduced on the basis of ecological economy. From the perspective of green ecological planning and economy, practice has proved that new urban planning is able to promote the establishment of a resource-saving society, to enhance the coordinated development of the population, resources, environment, and economy, and to comprehensively improve people's quality of life.

The purpose of this paper is to review the relevant literature in order to identify trends and suggest some possible directions for future research in the framework of humanitarian aid distribution logistics with accessibility constraints.

The authors developed a systematic literature review to study the state of the art on distribution logistics considering accessibility constraints. The electronic databases used were Web of science, Scopus, Science Direct, Jstor, Emerald, EBSCO, Scielo and Redalyc. As a result, 49 articles were reviewed in detail.

This study identified some gaps, as well as some research opportunities. The main conclusions are the need for further studies on the interrelationships and hierarchies of multiple actors, explore intermodality, transshipment options and redistribution relief goods to avoid severe shortages in some nodes and excess inventory in others, studies of the vulnerability of transport networks, correlational analysis of road failures and other future lines.

The bibliography is limited to peer-reviewed academic journals due to their academic relevance, accessibility and ease of searching. Most of the studies included in the review were conducted in high-income countries, which may limit the generalizability of the results to low-income countries. However, the authors focused on databases covering important journals on humanitarian logistics.

This paper contextualises and synthesises research into humanitarian aid distribution logistics with accessibility constrains, highlights key themes and suggests areas for further research.