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The purpose of this paper is to propose a robotic system for percutaneous surgery. The key component in the system, a robotic arm that can manipulate a puncture needle is presented. The mechanical design, the motion control and the force control method of the robotic arm are discussed in the paper.

The arm with an arc mechanism placed on a 3D Cartesian stage is developed as a puncture needle manipulator to locate the position of the needle tip, tune the needle’s posture and actuate the puncture motion under the visual guidance of two orthogonal X-ray images of a patient by a surgeon. A focusing method by using two laser spots is proposed to automatically move the needle tip to a surgery entry point on the skin. A dynamics model is developed to control the position of the needle mechanism and an explicit force control strategy is utilized to perform the needle insertion.

With the surgical system, a surgeon can easily perform puncture operation by taking two orthogonal real-time X-ray images as a visual feedback and accurately navigating the needle insertion. The laser-guided focusing method is efficient in placement of the needle tip. The explicit force control strategy is proved to be effective for holding constant and stable puncture force in experiments.

The robotic arm has an advantage in easy redirection of the needle because the rotation and the translation are decoupled in the mechanism. By adopting simple laser pens and a well-developed kinematics model, the system can handle the entry point, locating task automatically. The focusing method and the force control method proposed in the paper are useful for the present system and could be intuitive for similar surgical robots.

This review aims to give a critical view of the wheel/rail high frequency vibration-induced vibration fatigue in railway bogie.

Vibration fatigue of railway bogie arising from the wheel/rail high frequency vibration has become the main concern of railway operators. Previous reviews usually focused on the formation mechanism of wheel/rail high frequency vibration. This paper thus gives a critical review of the vibration fatigue of railway bogie owing to the short-pitch irregularities-induced high frequency vibration, including a brief introduction of short-pitch irregularities, associated high frequency vibration in railway bogie, typical vibration fatigue failure cases of railway bogie and methodologies used for the assessment of vibration fatigue and research gaps.

The results showed that the resulting excitation frequencies of short-pitch irregularity vary substantially due to different track types and formation mechanisms. The axle box-mounted components are much more vulnerable to vibration fatigue compared with other components. The wheel polygonal wear and rail corrugation-induced high frequency vibration is the main driving force of fatigue failure, and the fatigue crack usually initiates from the defect of the weld seam. Vibration spectrum for attachments of railway bogie defined in the standard underestimates the vibration level arising from the short-pitch irregularities. The current investigations on vibration fatigue mainly focus on the methods to improve the accuracy of fatigue damage assessment, and a systematical design method for vibration fatigue remains a huge gap to improve the survival probability when the rail vehicle is subjected to vibration fatigue.

The research can facilitate the development of a new methodology to improve the fatigue life of railway vehicles when subjected to wheel/rail high frequency vibration.

This qualitative research explores the relationship between religiosity, suicide thoughts and drug abuse among 55 homeless people, interviewed with interpretative phenomenological analysis. Analyzing the thematic structure of the participants' narrations, important main themes appeared in order to avoid suicide, among which family, the certainty of finding a solution and the will to live. However, the suicide ideation inheres in about 30% of participants, almost all believers, addicted and/or alcoholics. Results suggest that religiosity and meaning of death neither prevent from substances abuse and alcoholism, nor is a protective factor against suicide ideation. Meanings of life are the most important reasons for living, and when they are definitively considered unworkable, alcohol and drug help to endure life in the street. A specific model is discussed.

Japan's decision to release nuclear wastewater into the Pacific Ocean in 2023 has sparked strong opposition at home and abroad. In this study, Graph Model for Conflict Resolution (GMCR) method is adopted to analyze the conflict problem, and reasonable equilibrium solutions are given to solve the conflict event.

In this study, GMCR is adopted to solve the conflict problem. First, identify the key decision-makers (DMs) on the issue of nuclear effluent and the relevant options they might adopt. Second, the options of each DM are arranged and combined to form a set of feasible states. Thirdly, the graph model is constructed according to the change of DM's options, and the relative preference of each DM is determined. Finally, the conflict problem is solved according to the definition of GMCR equilibrium.

Discharging nuclear wastewater into the ocean is not the right choice to solve the problem. Developing more space to store nuclear wastewater is more conducive to the protection of the ocean environment.

It is undesirable for the Japanese government to unilaterally discharge nuclear wastewater into the ocean. Objectively assessing the radioactivity of nuclear wastewater and the cooperation of relevant stakeholders can better solve this conflict.

The problem arising from Japan's releasing plan is complicated because of a lack of information and the existence of multiple stakeholders, while GMCR can help us with a better view of the current circumstance in the conflict.

This chapter looks at the sex trade in Japanese society and the manner in which it has been accepted for decades, both socially and legally, as a ‘necessary evil’. This passive and disinterested tolerance of the industry's quasi-legal state, neither banning prostitution completely nor ensuring that it follows the transparent rules and regulations expected of other industries, means that it fails to satisfy either of the primary views on transactional sex: prohibition or legalisation. The result is that the women involved in the industry are subject to various forms of exploitation and abuse that the Japanese government, by failing to take active steps to reform the industry in either direction, becomes complicit to. Shaped by personal interviews with members of the industry and the NGOs that provide them with support, the chapter provides an examination of the industry's historical development, its portrayal in popular media and the prevailing social norms regarding the industry. It then assesses the political and legal responses to the industry and the glaring oversights that exist in their failure to provide adequate support. Finally, it considers, based upon the self-expressed interests of the women working in the industry, in what areas meaningful reform might occur.

Did Chinese cities whose public health departments are headed by medical professionals fare better in fighting coronavirus disease 2019 (COVID-19)?

The authors collected the professional background of the directors of the public health departments of 350 Chinese cities, which include 87% of the Chinese population. Excluding Wuhan, the epicenter of COVID-19, the authors analyzed the infection rates and death rates from COVID-19 between 131 Chinese cities whose public health departments are led by medical professionals and 218 cities whose public health departments are led by nonprofessionals. The authors employed a multivariate regression controlling for the number of people that traveled from Wuhan to each city, the local economic development and the number of hospital beds.

Chinese cities whose public health departments are led by medical professionals had 21 fewer confirmed cases per 10 million as of January 31, 2020 [95% CI, −40 to −3], 58 fewer cases per 10 million in the next 10 days [95% CI, −116 to 0], similar new cases between February 11 and February 20, 2020, and 3 fewer deaths per 10 million as of February 20, 2020 [95% CI, −7 to 0].

Association could not make a strong causal claim.

Local public health authorities are critical for combating a pandemic. The authors found that Chinese cities whose public health departments are headed by medical professionals were associated with lower infection rates and fewer death rates from COVID-19. The results were significant only at the start of the outbreak. This study’s results suggest that to better combat a pandemic, local public health authorities should be led by competent people who have a medical background.

The authors provide the first empirical evidence about the association between a local public health head's competence and the infection rate and death rate of COVID-19. The authors’ manually collected data also show that only 38% of the heads of the public health departments of Chinese cities have a medical background.