50 research outputs found
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An Investigation of Ceratomyxa shasta sporulation following death of itsChinook salmon host
As pre-spawning mortality (PSM) in Chinook salmon in the Willamette River Valley becomes a more defined and examined area of study, more focus is granted to not only preserving the health of these fish, but also expanding knowledge concerning various pathogens that utilize the salmon as hosts and may be associated with PSM. One such parasite, a myxozoan named Ceratomyxa shasta, has been known to be extremely detrimental to salmon health, yet little literature exists concerning what exactly happens to this parasite once the salmon die. This thesis briefly outlines the complexity regarding this parasite’s relationship with the Chinook salmon, offers some context to transmission dynamics, and explores a recent investigation conducted over the course of the 2013-2014 academic year to determine the capability of Ceratomyxa shasta to live, continue to develop, and sporulate following the death of one of its hosts, the Chinook salmon
Experimental and Simulation Efforts in the Astrobiological Exploration of Exooceans
The icy satellites of Jupiter and Saturn are perhaps the most promising places in the Solar System regarding habitability. However, the potential habitable environments are hidden underneath km-thick ice shells. The discovery of Enceladus’ plume by the Cassini mission has provided vital clues in our understanding of the processes occurring within the interior of exooceans. To interpret these data and to help configure instruments for future missions, controlled laboratory experiments and simulations are needed. This review aims to bring together studies and experimental designs from various scientific fields currently investigating the icy moons, including planetary sciences, chemistry, (micro-)biology, geology, glaciology, etc. This chapter provides an overview of successful in situ, in silico, and in vitro experiments, which explore different regions of interest on icy moons, i.e. a potential plume, surface, icy shell, water and brines, hydrothermal vents, and the rocky core
Planetary Exploration Horizon 2061 Report, Chapter 3: From science questions to Solar System exploration
This chapter of the Planetary Exploration Horizon 2061 Report reviews the way
the six key questions about planetary systems, from their origins to the way
they work and their habitability, identified in chapter 1, can be addressed by
means of solar system exploration, and how one can find partial answers to
these six questions by flying to the different provinces to the solar system:
terrestrial planets, giant planets, small bodies, and up to its interface with
the local interstellar medium. It derives from this analysis a synthetic
description of the most important space observations to be performed at the
different solar system objects by future planetary exploration missions. These
observation requirements illustrate the diversity of measurement techniques to
be used as well as the diversity of destinations where these observations must
be made. They constitute the base for the identification of the future
planetary missions we need to fly by 2061, which are described in chapter 4.
Q1- How well do we understand the diversity of planetary systems objects? Q2-
How well do we understand the diversity of planetary system architectures? Q3-
What are the origins and formation scenarios for planetary systems? Q4- How do
planetary systems work? Q5- Do planetary systems host potential habitats? Q6-
Where and how to search for life?Comment: 107 pages, 37 figures, Horizon 2061 is a science-driven, foresight
exercise, for future scientific investigation
Uranus and Neptune missions: A study in advance of the next Planetary Science Decadal Survey
The ice giant planets, Uranus and Neptune, represent an important and relatively unexplored class of planet. Most of our detailed information about them comes from fleeting looks by the Voyager 2 spacecraft in the 1980s. Voyager, and ground-based work since then, found that these planets, their satellites, rings, and magnetospheres, challenge our understanding of the formation and evolution of planetary systems. We also now know that Uranus-Neptune size planets are common around other stars. These are some of the reasons ice giant exploration was a high priority in NASA's most recent Planetary Science Decadal Survey. In preparation for the next Decadal Survey, NASA, with ESA participation, conducted a broad study of possible ice giant missions in the 2024-2037 timeframe. This paper summarizes the key results of the study, and addresses questions that have been raised by the science community and in a recent NASA review. Foremost amongst these are questions about the science objectives, the science payload, and the importance of an atmospheric probe. The conclusions of the NASA/ESA study remain valid. In particular, it is a high priority to send an orbiter and atmospheric probe to at least one of the ice giants, with instrumentation to study all components of an ice giant system. Uranus and Neptune are found to be equally compelling as science targets. The two planets are not equivalent, however, and each system has things to teach us the other cannot. An additional mission study is needed to refine plans for future exploration of these worlds
The case for a New Frontiers-class Uranus Orbiter:System science at an underexplored and unique world with a mid-scale mission
Current knowledge of the Uranian system is limited to observations from the flyby of Voyager 2 and limited remote observations. However, Uranus remains a highly compelling scientific target due to the unique properties of many aspects of the planet itself and its system. Future exploration of Uranus must focus on cross-disciplinary science that spans the range of research areas from the planet's interior, atmosphere, and magnetosphere to the its rings and satellites, as well as the interactions between them. Detailed study of Uranus by an orbiter is crucial not only for valuable insights into the formation and evolution of our solar system but also for providing ground truths for the understanding of exoplanets. As such, exploration of Uranus will not only enhance our understanding of the ice giant planets themselves but also extend to planetary dynamics throughout our solar system and beyond. The timeliness of exploring Uranus is great, as the community hopes to return in time to image unseen portions of the satellites and magnetospheric configurations. This urgency motivates evaluation of what science can be achieved with a lower-cost, potentially faster-turnaround mission, such as a New Frontiers–class orbiter mission. This paper outlines the scientific case for and the technological and design considerations that must be addressed by future studies to enable a New Frontiers–class Uranus orbiter with balanced cross-disciplinary science objectives. In particular, studies that trade scientific scope and instrumentation and operational capabilities against simpler and cheaper options must be fundamental to the mission formulation
Finishing the euchromatic sequence of the human genome
The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead
Neptune Odyssey: A Flagship Concept for the Exploration of the Neptune–Triton System
The Neptune Odyssey mission concept is a Flagship-class orbiter and atmospheric probe to the Neptune-Triton system. This bold mission of exploration would orbit an ice-giant planet to study the planet, its rings, small satellites, space environment, and the planet-sized moon Triton. Triton is a captured dwarf planet from the Kuiper Belt, twin of Pluto, and likely ocean world. Odyssey addresses Neptune system-level science, with equal priorities placed on Neptune, its rings, moons, space environment, and Triton. Between Uranus and Neptune, the latter is unique in providing simultaneous access to both an ice giant and a Kuiper Belt dwarf planet. The spacecraft - in a class equivalent to the NASA/ESA/ASI Cassini spacecraft - would launch by 2031 on a Space Launch System or equivalent launch vehicle and utilize a Jupiter gravity assist for a 12 yr cruise to Neptune and a 4 yr prime orbital mission; alternatively a launch after 2031 would have a 16 yr direct-to-Neptune cruise phase. Our solution provides annual launch opportunities and allows for an easy upgrade to the shorter (12 yr) cruise. Odyssey would orbit Neptune retrograde (prograde with respect to Triton), using the moon's gravity to shape the orbital tour and allow coverage of Triton, Neptune, and the space environment. The atmospheric entry probe would descend in ~37 minutes to the 10 bar pressure level in Neptune's atmosphere just before Odyssey's orbit-insertion engine burn. Odyssey's mission would end by conducting a Cassini-like "Grand Finale,"passing inside the rings and ultimately taking a final great plunge into Neptune's atmosphere
