Methods in molecular biology
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Simulated microgravity and partial gravity research on Earth is highly convenient for every space biology researcher due to limitations of access to spaceflight. However, the use of ground-based facilities for microgravity simulation is far from simple. ⋯ Furthermore, ground-based facilities are also capable of generating hypergravity or fractional gravity conditions, which are worth being tested and compared with the results of microgravity exposure. Multiple technologies (2D clinorotation, random positioning machines, magnetic levitators or centrifuges), experimental hardware (proper use of containers and substrates for the seedlings or cell cultures), and experimental requirements (some life support/environmental parameters are more difficult to provide in certain facilities) should be collectively considered in defining the optimal experimental design that will allow us to anticipate, modify, or redefine the findings provided by the scarce spaceflight opportunities that have been (and will be) available.
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The growth and development of plants during spaceflight have important implications for both basic and applied research supported by NASA and other international space agencies. While there have been many reviews of plant space biology, the present chapter attempts to fill a gap in the literature on the actual process and methods of performing plant research in the spaceflight environment. The author has been a principal investigator on six spaceflight projects and has another two space experiments in development. ⋯ Additional issues considered are working at NASA centers, hardware development, safety concerns, and the engineering versus science culture in space agencies. The difficulties of publishing the results from spaceflight research based on such factors as the lack of controls, limited sample size, and the indirect effects of the spaceflight environment also are summarized. Finally, lessons learned from these spaceflight experiences are discussed in the context of improvements for future space-based research projects with plants.
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Sepsis is one of the oldest and most elusive syndromes in medicine. With the confirmation of germ theory by Semmelweis, Pasteur, and others, sepsis was considered as a systemic infection by a pathogenic organism. Although the germ is probably the beginning of the syndrome and one of the major enemies to be identified and fought, sepsis is something wider and more elusive. In this chapter clinically relevant themes of sepsis will be approached to provide an insight of everyday clinical practice for healthcare workers often not directly involved in the patient's management.
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The number of studies published in the biomedical literature has dramatically increased over the last few decades. This massive proliferation of literature makes clinical medicine increasingly complex, and information from multiple studies is often needed to inform a particular clinical decision. ⋯ Because it is often impractical for readers to track down and review all the primary studies, systematic reviews and meta-analyses are an important source of evidence on the diagnosis, prognosis, and treatment of any given disease. This chapter summarizes methods for conducting and reading systematic reviews and meta-analyses, as well as describing potential advantages and disadvantages of these publications.
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Clinical epidemiology is the science of human disease investigation with a focus on diagnosis, prognosis, and treatment. The generation of a reasonable question requires definition of patients, interventions, controls, and outcomes. ⋯ The hierarchy of evidence for clinical decision-making places randomized controlled trials (RCT) or systematic review of good quality RCTs at the top of the evidence pyramid. Prognostic and etiologic questions are best addressed with longitudinal cohort studies.