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A common phytoene synthase mutation underlies white petal varieties of the California poppy.
The California poppy (Eschscholzia californica) is renowned for its brilliant golden-orange flowers, though white petal variants have been described. By whole-transcriptome sequencing, we have discovered in multiple white petal varieties a single deletion leading to altered splicing and C-terminal truncation of phytoene synthase (PSY), a key enzyme in carotenoid biosynthesis. Our findings underscore the diverse roles of phytoene synthase in shaping horticultural traits, and resolve a longstanding mystery of the regaled golden poppy
Tectonic Studies of the Atlantic Margin in the Southeastern United States
Reanalysis of published seismic and well data from the South Georgia Embayment provides important new constraints on the geologic structure and evolution of the Eastern North American margin. A lower Paleozoic stratigraphic section (Silurian to Devonian) sampled in offshore wells drilled in the late 1970’s, can be correlated continuously along the entire ~250 km N-S length of the BA-3 profile acquired in 1989. Other than gentle warping and minor fault offsets, this Paleozoic section is essentially undeformed, precluding both Paleozoic contractional deformation associated with Appalachian orogeny, or subsequent Mesozoic extensional deformation and magmatism associated with continental rifting and formation of the Central Atlantic. Accordingly, crustal properties generating the Brunswick Magnetic Anomaly (BMA) in the central portion of the profile were most likely imparted during Proterozoic tectonic and magmatic processes, and the BMA is an inherited feature of the Gondwanan continental crust pre-dating the basal Paleozoic unconformity. Similar “layered basement” was previously identified on numerous other seismic reflection profiles on the continental margin, implying (1) the Suwanee and Brunswick/Charleston terranes were part of Gondwana, and acted as a coherent and stable block of continental crust throughout the Phanerozoic evolution of southeastern North America, and (2) the Alleghanian suture must sit north of these occurrences, and most likely coincides with the boundary on the magnetic map defined by Higgins and Zietz (1983). Paleozoic collisional tectonics were subsequently followed by extensional processes during the Mesozoic. The southern central Atlantic Ocean along the east coast of North America is commonly associated with a large volcanic province, referred to as the Central Atlantic Magmatic Province (CAMP) emplaced during this time of extension. A prominent seismic reflection, known as the J-Horizon, underlies this entire region and has been historically correlated to a sedimentary basalt contact. However, the J-Horizon has been reevaluated onshore as a contact between Coastal Plain sediments and the base of the coastal plain, regardless of the presence of basalt. This study reevaluates the character and origin of the J-Horizon beneath the Carolina Trough and Blake Plateau Basin in order to reevaluate the extent of a continental flood basalt associated with CAMP. Offshore wells have been identified near the distribution of “J” that penetrate basement rock, none of which encounter Jurassic basalt; however, no wells have been directly drilled in this proposed region. From correlating well and seismic data throughout the region, analysis suggests that, as with the onshore, the J Horizon represents a boundary between overlying Coastal Plain sedimentary rocks, and underlying Mesozoic rift basin and Paleozoic basement rocks. These data indicate that CAMP is not as aerially widespread as previously estimated in the Southeastern United States. This new interpretation removes the strongest line of evidence connecting the central Southern Atlantic Ocean to open 200 Ma and consequently removes evidence suggesting the opening of the central Atlantic Ocean of North America was diachronus
The Enhanced WUDMA Image Processing System
This document describes recent enhancements to the WUDMA image processing laboratory that implement improvements suggested by experience gained during the WUDMA I program. More recent improvements to the software are mentioned as well as a discussion of some of the design issues faced during the early stages of conception. Finally, some ongoing projects and future plans are mentioned
The WUDMA Image Processing System
The WUDMA Image Processing System provides a framework that allows many image processing packages to function as the single system. It currently contains several packages that provide a powerful range of image processing tools for use in teaching and research. The WUDMA System overcomes the lack of standardization in image processing by providing bridges between diverse software packages and shielding the user from incompatibilities inherent in the software. As such, it may be considered as a paradigm from integrating packages in other application areas
Oral Biofilms: Development, Control, and Analysis
The oral cavity harbors hundreds of microbial species that are present either as planktonic cells or incorporated into biofilms. The majority of the oral microbes are commensal organisms. Those that are pathogenic microbes can result in oral infections, and at times can initiate systemic diseases. Biofilms that contain pathogens are challenging to control. Many conventional antimicrobials have proven to be ineffective. Recent advances in science and technology are providing new approaches for pathogen control and containment and methods to characterize biofilms. This perspective provides (1) a general understanding of biofilm development; (2) a description of emerging chemical and biological methods to control oral biofilms; and (3) an overview of high-throughput analytical approaches to analyze biofilms
Supporting Collaborative Health Tracking in the Hospital: Patients' Perspectives
The hospital setting creates a high-stakes environment where patients' lives depend on accurate tracking of health data. Despite recent work emphasizing the importance of patients' engagement in their own health care, less is known about how patients track their health and care in the hospital. Through interviews and design probes, we investigated hospitalized patients' tracking activity and analyzed our results using the stage-based personal informatics model. We used this model to understand how to support the tracking needs of hospitalized patients at each stage. In this paper, we discuss hospitalized patients' needs for collaboratively tracking their health with their care team. We suggest future extensions of the stage-based model to accommodate collaborative tracking situations, such as hospitals, where data is collected, analyzed, and acted on by multiple people. Our findings uncover new directions for HCI research and highlight ways to support patients in tracking their care and improving patient safety
A Verified Information-Flow Architecture
SAFE is a clean-slate design for a highly secure computer system, with
pervasive mechanisms for tracking and limiting information flows. At the lowest
level, the SAFE hardware supports fine-grained programmable tags, with
efficient and flexible propagation and combination of tags as instructions are
executed. The operating system virtualizes these generic facilities to present
an information-flow abstract machine that allows user programs to label
sensitive data with rich confidentiality policies. We present a formal,
machine-checked model of the key hardware and software mechanisms used to
dynamically control information flow in SAFE and an end-to-end proof of
noninterference for this model.
We use a refinement proof methodology to propagate the noninterference
property of the abstract machine down to the concrete machine level. We use an
intermediate layer in the refinement chain that factors out the details of the
information-flow control policy and devise a code generator for compiling such
information-flow policies into low-level monitor code. Finally, we verify the
correctness of this generator using a dedicated Hoare logic that abstracts from
low-level machine instructions into a reusable set of verified structured code
generators
Developing a Model Curriculum for a University Course in Health Impact Assessment in the United States
As Health Impact Assessment (HIA) become increasingly common in the U.S. there is growing demand for instruction beyond sho1i courses and online training. As of October 2013, there are graduate level courses that include instruction on HIA in at least 17 universities in the U.S., including 4 courses that focus explicitly on HIA. Instructors of these four courses collaborated to develop a model curriculum for teaching HIA that draws on a framework for experiential learning and on a theoretical model of curriculum formulation. This article includes an in-depth analysis of these courses and presents a model curriculum for HIA instruction during an academic quaiier or semester course in a University. This model curriculum may help faculty develop a graduate level HIA course at their institution, as well as inform public health and community design professionals interested in building capacity to conduct HIAs, and students considering taking an HIA course. International instructors could also learn from the U.S. experience, and apply the model curriculum to their setting and educational structure.This work was supported in part by the Johns Hopkins Bloomberg School of Public Health
Faculty Innovation Fund
A gravity model for the lithosphere in western Kenya and northeastern Tanzania
We present a new gravity model for the lithosphere beneath the Kenya Rift Valley, the Mozambique Belt, and the Tanzania Craton in western Kenya and northeastern Tanzania. The Kenya Rift lies within the eastern branch of the extensive Cenozoic East African Rift System and has developed almost entirely in the Pan-African Mozambique Belt about 50 to 150 km east of the exposed margin of the Archean Tanzania Craton. The gravity field over western Kenya and northeastern Tanzania is characterized by a long-wavelength Bouguer anomaly. We propose that this anomaly has two components: 1. (1) a "rift" signature, deriving from a shallow rift basin, a lower crustal intrusion and a low-density zone in the mantle lithosphere localized beneath the rift axis2. (2) a "suture" signature, arising from a crustal root along the boundary between the Mozambique Belt and Tanzania Craton and higher density crust in the mobile belt above part of the crustal root. Two lines of reasoning support our interpretation: 1. (1) Recent geological studies of the Mozambique Belt in Kenya and Tanzania suggest that it is a continent-continent collision zone, and continent-continent collision zones worldwide commonly exhibit a characteristic gravity anomaly.2. (2) The long-wavelength Bouguer anomaly has at least two minima, one over the craton-mobile belt boundary, and one or more over the rift valley. Corroborative evidence for our interpretation of the gravity field is provided by recent seismic investigations.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/29787/1/0000126.pd
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