21 research outputs found
Centrifuge: une expérience en microgravité réalisée par un groupe d'étudiants de l'Université et de l'Ecole Polytechnique Fédérale de Lausanne.
The interplanetary exchange of photosynthesis
Panspermia, the transfer of organisms from one planet to another, either through interplanetary or interstellar space, remains speculation. However, its potential can be experimentally tested. Conceptually, it is island biogeography on an interplanetary or interstellar scale. Of special interest is the possibility of the transfer of oxygenic photosynthesis between one planet and another, as it can initiate large scale biospheric productivity. Photosynthetic organisms, which must live near the surface of rocks, can be shown experimentally to be subject to destruction during atmospheric transit. Many of them grow as vegetative cells, which are shown experimentally to be susceptible to destruction by shock during impact ejection, although the effectiveness of this dispersal filter can be shown to be mitigated by the characteristics of the cells and their local environment. Collectively these, and other, experiments reveal the particular barriers to the cross-inoculation of photosynthesis. If oxygen biosignatures are eventually found in the atmospheres of extrasolar planets, understanding the potential for the interplanetary exchange of photosynthesis will aid in their interpretation
Opposing Lethal Wildlife Research When Nonlethal Methods Exist: Scientific Whaling as a Case Study
As our understanding of sentience in certain wildlife species grows, and technological advancements promote non-lethal data collection, we believe that we ought to adjust our field methods to incorporate a regime of best practice that prioritizes non-lethal methodologies over inhumane methods of lethal sampling. In addition, progress already made towards non-lethal methodologies in wildlife research needs to be promoted widely. In this paper, we examine whether lethal methods of whale research, using Japanese lethal scientific whaling as a case study, are ethical when the scientific information can be gained from non-lethal methods, and humane methods of killing are not available. As a part of a simple ethical decision-making model, we explore if a requirement for 'refinement' of scientific technique (sensu Russell & Burch 1959; three Rs), promoted extensively for laboratory-based animal experimentation, has direct applicability to scientific research involving free-living wildlife. We argue that 'refinement' is an appropriate ethical principle in all cases where scientific research involves a choice between non-lethal sampling and the deliberate killing of free-living wildlife for scientific purposes. We conclude that the welfare of individual animals and the conservation of free-living wildlife populations are both worthy of moral consideration and need not be incompatible in humane wildlife research and management
Genetic approaches in preeclampsia
Preeclampsia (PE) is a serious hypertensive disorder that affects up to 8% of all pregnancies annually. An established risk factor for PE is family history, clearly demonstrating an underlying genetic component to the disorder. To date, numerous genetic studies, using both the candidate gene and genome-wide approach, have been undertaken to tease out the genetic basis of PE and understand its origins. Such studies have identified some promising candidate genes such as STOX1 and ACVR2A. Nevertheless, researchers face ongoing challenges of replicating these genetic associations in different populations and performing the functional validation of identified genetic variants to determine their causality in the disorder. This chapter will review the genetic approaches used in the study of PE, discuss their limitations and possible confounders, and describe current strategies