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The phase equilibria of the Cu–Cr–Si ternary system were investigated via thermodynamic modeling coupled with key experiments. Seventeen ternary alloys were prepared to determine the isothermal sections of the Cu–Cr–Si system at 700 and 800 °C by combining X-ray diffraction (XRD) and scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM/EDS). No ternary compound was found. The solubilities of the third element in binary compounds in the Cu–Si and Cr–Si systems were measured. Based on the thermodynamic descriptions of three constitutive binary systems available in the literature as well as the experimental phase equilibria data obtained from the present work and literature, thermodynamic re-assessment of the Cu–Cr–Si system was carried out by the CALPHAD (CALculation of PHAse Diagrams) approach. The substitutional model and sublattice model were used to describe the solution phases and intermediate phases, respectively. A set of thermodynamic parameters of the Cu–Cr–Si system was obtained. The calculated isothermal sections and vertical section are in good agreement with most of the reliable experimental data. The liquidus projection and reaction scheme of the Cu–Cr–Si system over the whole composition were also presented.

BACKGROUND: Dynamic positron emission tomography (PET) is a powerful tool that provides useful quantitative information on physiological and biochemical processes. However, the low signal-to-noise ratio (SNR) in short dynamic frames is a challenge. OBJECTIVE: To get high SNR in the dynamic PET and to achieve high-quality PET parametric image are the objective of this study. METHODS: Low-rank (LR) modeling and edge-preserving prior are incorporated in this study with a unified mathematical framework to improve the SNR of a dynamic PET image series. The proposed algorithm is designed to reduce noise in homogeneous areas while preserving the edges of regions of interest. RESULTS: The performance of the proposed method (LRH) is compared both visually and quantitatively by using the classic Gaussian filter and an LR expression filter on a digital brain phantom and in vivo rat study. Experimental results demonstrate that the proposed filter can achieve superior visual and quantitative performance without sacrificing spatial resolution. CONCLUSIONS: The proposed LRH is considerably effective and exhibits great potential in processing dynamic PET data with high noise levels.

This is the protocol for the Nested PCR assay

Background Enterocytozoon bieneusi is the most common microsporidian species causing diarrhea and other intestinal disorders in humans and animals. Like other infectious diseases, microsporidiosis usually disproportionately affects poor populations. In China, some ethnic minority areas remain poor. Currently, no information of E. bieneusi infection is available in minority populations. The present aims were to understand occurrence and genetic characterizations of E. bieneusi in ethnic minority groups from a poverty-stricken ethnic township in Yunnan Province, and to assess risk factors for E. bieneusi infection. Methodology/Principal findings 289 fecal specimens were collected from Yao people (one specimen each) with and without diarrhea, in Yunnan Province. E. bieneusi was identified and genotyped by PCR and sequence analysis of the ITS region of the rRNA gene. An average prevalence of 8.30% (24/289) was observed and four genotypes were identified—genotype Peru6 (n = 21) and three novel genotypes (one each). Genotype Peru6 was detected in two family members in each of three families. In a phylogenetic analysis, all of four genotypes fell into group 1 with zoonotic potential. The people owning individual pit toilets had a statistically higher prevalence of E. bieneusi (16.67%, 12/72) than those using public pit toilets (6.06%, 12/198). Conclusions/Significance This is the first report on occurrence and genetic characteristics of E. bieneusi in ethnic minority groups in China. Genotype Peru6 was found in humans in China for the first time and showed dominance in Yao people. The same genotype was found in some family members and all the genotypes fell into group 1, suggesting the possibility of anthroponotic and zoonotic transmissions. The majority (83.33%, 20/24) of E. bieneusi positive individuals did not present diarrhea. In any case, it is important to recognize their existence and the importance that asymptomatic individuals to E. bieneusi may have from an epidemiological point of view, as transmitters of this pathogen. The analysis of risk factors provides scientific evidence for the development of effective strategies for prevention and control of E. bieneusi infection., Author summary Enterocytozoon bieneusi is the most prevalent opportunistic microsporidian species causing diarrhea in humans and animals worldwide. Due to frequent occurrence of chronic or life-threatening diarrhea mainly in HIV/AIDS patients and others patients such as elderly people, transplant recipients and cancer patients, epidemiological studies of E. bieneusi focus on this susceptible population. Asymptomatic carriers of E. bieneusi are often neglected, and their role in the transmission of this microorganism is not paid enough attention. The prevalence of E. bieneusi is also actually related to the geographical locations, the populations and the socioeconomic conditions. The infectious diseases usually disproportionately affect poor populations. In China, although total economy has developed rapidly, there is the regional imbalance in economic development and some minority areas remain poor. Thus, we carried out a molecular epidemiology survey of E. bieneusi among 289 Yao people with and without diarrhea from a poverty-stricken ethnic township. We identified E. bieneusi in 8.30% (24/289) of people, with the majority (83.33%, 20/24) of positive individuals having no diarrhea. Meanwhile, zoonotic genotype Peru6 was found to be dominant in infected people. Our study emphasizes the importance and significance in epidemiological surveys of E. bieneusi in non-diarrheal people and assessment of risk factors for E. bieneusi infection.

With the increasing number of clinical trials being undertaken in China over the last few years, stakeholders in human subjects protections (HSP) are facing many new challenges; currently, these challenges in HSP are largely taken up by the ethical review committees and study investigators. This article identifies a number of issues with the present system and suggests ways to resolve these issues at the institutional level. Though the Chinese government has developed a basic regulatory framework for HSP, further work still needs to be done. It is imperative that China develops a robust and reliable HSP system at the institutional level as drug studies are increasingly being undertaken in mainland China.

Truth-telling to competent patients is widely affirmed as a cardinal moral and biomedical obligation in contemporary Western medical practice. In contrast, Chinese medical ethics remains committed to hiding the truth as well as to lying when necessary to achieve the family's view of the best interests of the patient. This essay intends to provide an account of the framing commitments that would both justify physician deception and have it function in a way authentically grounded in the familist moral concerns of Confucianism. It reflects on the moral conditions and possibilities for sustaining a Confucian understanding of truth-telling and consent in mainland China.

Today's students with knowledge of medicine will be tomorrow's medical practitioners. They will face not cold stones or objects, but patients with flesh and feelings. They must provide not only technical skills and therapy, but also compassion and care. The philosophy that medicine is a humane art has roots in Chinese culture: the famous Tang Dynasty physician Simiao Sun (541-682 B.C.), noted that "a respectable physician is expected to be both skilful and honest.[1] The industrial and technological revolution in Western medicine that began in the fourteenth and fifteenth centuries brought great changes in perspectives on health and disease, leading to the biomedical model and its belief that "chemical and physical languages can eventually explain biological phenomena."[2] The biomedical model has accelerated the development of medical science, but has separated the physical from the natural, psychological, and social dimensions of human illness and well-being. Disease was isolated from the human body as a whole; medical practice became disease-centered, and the patient is neglected as a human being. At the same time, medical training stresses knowledge and skills preparation, while overlooking the orientation of professional values. Such developments led G. L. Engel, of Rochester University School of Medicine, to propose the "bio-psycho-social" model in 1977, which stresses the integration of biological, psychological, and social dimensions of illness. In response, a new model of patient-centered practice is evolving, one that enhances both scientific and ethical values in medicine. The extensive application of high technology in clinical practice has produced positive results. But if falsely managed, it can also harm the patient's well-being. This too has led to re-examination of the ethical values at stake in high technology care and even of the general goals of medical profession. These focus our attention on the need for continuing the reform in medical education and especially on the importance of comprehensive character development of medical students. Much emphasis is put on the humane and social values of the profession. As a result, much importance is attached to ethics teaching in order to provide the society with medical practitioners both intellectually and behaviorally competent. Objectives of Ethics Teaching Medical education in China is generally offered in two connected and progressive phases. The first phase emphasizes basic medical knowledge in the classroom, while the second phase focuses on clinical training in teaching hospitals, which covers the last few years before graduation. Ethics teaching goes through the two phases and extends into continued education after graduation. It includes ethics courses taught by teachers of ethics and development of professional character under the supervision of clinical teachers. The objectives of both phases are the same, namely, (1) to develop good morals and professional values for the establishment of good interpersonal relationships, especially between patients and physicians, (2) to develop the ability to judge and analyze ethical problems as the foundation of decisionmaking, and (3) to call attention to the ethical problems evolved by high technology in medical practice and minimize its negative consequences. Formal Ethical Courses. Formal ethics courses offered to students include: (1) general ethics taught in the pre-clinic phase, (2) medical ethics taught during clinical training, and (3) seminars on special topics during clinical internship. Training and development of ethics teachers. Teachers play a guiding role in the teaching of ethics, and development of a cohort of competent ethics teachers is essential. In Beijing Medical University both physicians and teachers of philosophy serve as ethics faculty. Our training program for the former emphasizes principles and knowledge and theory of ethics, while the program for the latter focuses on necessary medical knowledge and general understanding of clinical practice. …