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Extrusion-based additive manufacturing (AM) has been considered as a promising technique to fabricate scaffolds for tissue engineering due to affordability, versatility and ability to print porous structures. The reliability and controllability of the printing process are necessary to produce 3D-printed scaffolds with desired properties and depend on the geometric characteristics such as porosity and pore diameter. The purpose of this study is to develop an analytical model and explore its effectiveness in the prediction of geometric characteristics of 3D-printed scaffolds.

An analytical model was developed to simulate the geometric characteristics of scaffolds produced by extrusion-based AM using fluid mechanics. Polycaprolactone (PCL) was chosen as a scaffold material and was assumed to be a non-Newtonian fluid for the model. The effectiveness of the model was verified through comparison with the experimental results.

A comparison study between simulation and experimental results shows that strut diameter, pore size and porosity of scaffolds can be predicted by using extrusion pressure, temperature, nozzle diameter, nozzle length and printing speed. Simulation results demonstrate that geometric characteristics have a strong relationship with processing parameters, and the model developed in this study can be used for predicting the scaffold properties for the extrusion-based 3D bioprinting process.

The present study provides a prediction model that can simulate the printing process by a simple input of processing parameters. The geometric characteristics can be predicted prior to the experimental verification, and such prediction will reduce the process time and effort when a new material or method is applied.

A continuum model helps us understand contemporary information politics. One end describes authority-centric approaches, including governments and digital corporations, while the other focuses on teaching individual skills and the understanding needed to grapple productively with the digital information ecosystem. The extremes represent opposed views of human agency, current information enterprises, and the nature of media. We apply this continuum to two examples, QAnon and COVID-19. Two instances attempt to connect the model's two poles. We conclude with a forecast of the continuum's viability and then project its application forward in education.

The Bureau of Economics in the Federal Trade Commission has a three-part role in the Agency and the strength of its functions changed over time depending on the preferences and ideology of the FTC’s leaders, developments in the field of economics, and the tenor of the times. The over-riding current role is to provide well considered, unbiased economic advice regarding antitrust and consumer protection law enforcement cases to the legal staff and the Commission. The second role, which long ago was primary, is to provide reports on investigations of various industries to the public and public officials. This role was more recently called research or “policy R&D”. A third role is to advocate for competition and markets both domestically and internationally. As a practical matter, the provision of economic advice to the FTC and to the legal staff has required that the economists wear “two hats,” helping the legal staff investigate cases and provide evidence to support law enforcement cases while also providing advice to the legal bureaus and to the Commission on which cases to pursue (thus providing “a second set of eyes” to evaluate cases). There is sometimes a tension in those functions because building a case is not the same as evaluating a case. Economists and the Bureau of Economics have provided such services to the FTC for over 100 years proving that a sub-organization can survive while playing roles that sometimes conflict. Such a life is not, however, always easy or fun.

Using the concept red tape, the purpose of this paper is to understand how job context, and especially hierarchical position, shapes the effects of transformational leadership on employee rule perception.

A survey of South Korean central government employees across a range of organizations and hierarchical positions is used to capture perception of rule dysfunction and leadership. Hierarchical linear modeling is used to test the hypotheses generated from a review of relevant literature.

The analysis suggests that perceived transformational leadership behaviors are associated with weakened perception of rule dysfunction. However, this relationship is relevant only for employees at higher echelons of the organization, which in turn suggests that the rule perception of frontline employees is determined by other factors.

The principle limitation of this study is its use of cross-sectional data, which precludes the demonstration of causal influence between the dependent and independent variables.

This study makes several contributions to the literature. Most importantly, while it has been found that characteristics at the organization level influence the effects of transformational leadership, the present study extends this theory to individual job context by incorporating hierarchical level into the analysis.

The use of performance management (PM) tools is a defining characteristic of public sector management. However, while research on PM is extensive, comparatively little focuses on how the practice shapes the attitudes and behavior of employees. The purpose of this paper is to address this question and develop a conditional process model that links PM to turnover intention. The model predicts that the PM-turnover relationship is mediated by job satisfaction and moderated by job-goal alignment.

The authors use a unique data set drawn from the Russian public sector to test the model empirically. Conditional process modeling is used to test for moderated mediation. The effects are further explored using bootstrapped bias-corrected confidence intervals.

The analysis suggests that PM has an indirect effect on turnover intention via job satisfaction in the average case. However, the indirect effect is stronger for employees who perceive that their work contributes directly to organizational goals. In contrast, for employees whose work lacks organizational goal alignment, PM has no significant effect.

Despite being an instrument to manage organizational (including human) resources, few studies have linked PM to employee-level outcomes. By doing so, this study implies promising research paths that can help generate a more complete picture of how PM shapes organizational processes in the public sector.

The purpose of this paper is to explore the concept of restorative justice as a tool for rebuilding trust and repairing damaged relationships in the workplace.

The literature on restorative justice, found predominantly in the criminology field, is reviewed, and the origins and tenets of restorative justice are explained.

Research suggests that the goals of restorative justice are to repair the harm after a damaging incident, to repair the damaged relationship between the two parties in conflict, and restore the offender back to the community.

Restorative justice promises to address the issue of repairing damaged relationships at work, a critical problem in organizations that has yet to be thoroughly addressed in the management literature.

This chapter gives one version of the recent history of evaluation case study. It looks back over the emergence of case study as a sociological method, developed in the early years of the 20th Century and celebrated and elaborated by the Chicago School of urban sociology at Chicago University, starting throughout the 1920s and 1930s. Some of the basic methods, including constant comparison, were generated at that time. Only partly influenced by this methodological movement, an alliance between an Illinois-based team in the United States and a team at the University of East Anglia in the United Kingdom recast the case method as a key tool for the evaluation of social and educational programmes.

Due to the scope of procurement in the public sector, public procurement policy has the potential to shape the behavior of market actors and promote the growth of businesses with socially relevant characteristics. This chapter looks at the public procurement process in South Korea as well as the implementation of the country’s e-procurement system. Public procurement is vulnerable to corruption in various ways, and Korea’s KONEPS e-procurement system has reduced corruption in the procurement process by increasing transparency, the persistence of data, and the probability of detecting irregularities. Second, this chapter explores how Korea has increasingly incorporated sustainable procurement principles into procurement policy, attempting to foster innovative and environmentally friendly companies, as well as those led by individuals belonging to socially disadvantaged groups. The chapter concludes with a discussion of some of the historical and organizational factors underlying Korea’s successes in public procurement in order to better understand the extent to which currently developing countries can draw upon the Korean case to improve their own procurement policies.

This paper evaluates the modern baseline presumption of nonconsent in sexual assault (rape) cases in light of different theories of sexuality (feminism on the one hand and sex positivism/queer theory on the other) and in light of how sexuality manifests itself in the lives of contemporary young women. The authors analyze social science literature on contemporary heterosexual practices such as sexting and hook-ups, as well as contemporary media imagery, to inform a contemporary understanding of the ways in which young people perceive and experience sex. Using this evidence as a foundation, the authors reconsider the ongoing utility of a baseline presumption of nonconsent in sexual assault cases. This paper demonstrates the complex relationship between women’s sexual autonomy, the contemporary culture’s encouragement of women’s celebration of their own sexual objectification and the persistence of high rates of unwanted sex. In the end, it demonstrates why a legal presumption against consent may neither reduce the rate of nonconsensual sex, nor raise the rate of reported rapes. At the same time, it shows how the presumption itself is unlikely to generate harmful consequences: if it deters anything, it likely deters unwanted sex, whether consented to or not.

This paper aims to explore the conceptual, tactical and institutional tensions between short-term and long-term engagement of humanitarian actors in the built environment, as framed through disaster resilience and transformative adaptation, respectively. The paper seeks to synthesize a more resolute understanding of the limits and challenges associated with each concept in the advancement of analytical and practical clarity.

This commentary paper is based, in part, on a literature review in disaster resilience, humanitarian design and planning and climate change adaptation scholarship.

This commentary paper highlights some of the critical weaknesses associated with a disaster resilience framing of humanitarian design and planning in the built environment.

The value of this viewpoint paper is to challenge the short-term, single equilibrium applications of disaster resilience in favor of longer-term perspectives associated with transformative adaptation. The intent is not to highlight a conceptual inferiority but to position these concepts as point and counter-point with the potential for complimentary and conflicting applications.