374 research outputs found

    Multimodal Needs Assessments for Curricular Refinement – Learner, Expert, EMR

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    OBJECTIVES •Explore the educational formats and resource preferences of house staff •Identify ICU topics thought to be important by experts in the field •Identify clinically relevant ICU topics •Build an interactive, standardized cognitive aid that serves both as an instructional resource for house staff and a prompt for those teachin

    Loving the Longshot: Risk Taking with Skewed Gambles

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    To examine the effect of increased skewness on risk taking, we conduct controlled laboratory experiments. Our instrument is an adaption of the Eckel and Grossman (2002, 2008) risk measure (with six gamble choices). The Eckel and Grossman measure is a simplest, easy to understand, exercise that gives sufficient heterogeneity in choices while at the same time minimizing errors. Its simplicity also makes it easy to adapt. The adapted gamble choices are designed to have the same expected payoffs and risk as the original gamble choices, but to exhibit increasing degrees of right skewness. The adapted instrument is used to address the question; does skewness encourage greater or less risk taking? Does the possibility of winning a high-earnings, long shot encourage people into greater or less overall risk taking? It also permits us to confirm, in a controlled environment, that people prefer positive skewness

    A Study of Space Arts in Relationship to Appreciation

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    169 pagesSeveral fields of cultural endeavor have sought to explain the appreciative experience with reference to the various concepts characterizing it in each field. Philosophers have thought to explain the appreciative theory in terms of a single element. Psychologists have been concerned with the empirical and objective elements of the appreciative experience as they relate to the abilities and capacities of individual appreciators. Educators have considered the appreciation of art with reference to the part it plays in establishing desirable social attitudes and enabling evaluations of aesthetic values. Artists have centered their attention upon the aesthetic and functional elements of those materials which are the common substance of the arts. The concept of these thinkers with reference to art appreciation have been sought in effort to clarify the problem period emergent from the consideration given to the appreciation of art on the part of these thinkers are those concerns which sent her about the nature of the appreciative problem with respect to the social and individual personality factors characterizing it. Because of the existing confusion regarding the nature of these factors, this study was undertaken as an attempt to determine the elements which characterize the appreciative experiences of a selected group of students with reference to certain art forms. From such an analysis it was hoped to learn more about the appreciation of space art insofar as it is dependent upon perception and to gain insight into the nature and source of such perception. The entire study considers the appreciation of space art in regard to its worth as a factor of social advancement

    Autonomous Plasmid-like Replication of a Conjugative Transposon

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    Integrative and conjugative elements (ICEs), a.k.a. conjugative transposons, are mobile genetic elements involved in many biological processes, including pathogenesis, symbiosis and the spread of antibiotic resistance. Unlike conjugative plasmids that are extra-chromosomal and replicate autonomously, ICEs are integrated in the chromosome and replicate passively during chromosomal replication. It is generally thought that ICEs do not replicate autonomously. We found that when induced, Bacillus subtilis ICEBs1 undergoes autonomous plasmid-like replication. Replication was unidirectional, initiated from the ICEBs1 origin of transfer, oriT, and required the ICEBs1-encoded relaxase NicK. Replication also required several host proteins needed for chromosomal replication, but did not require the replicative helicase DnaC or the helicase loader protein DnaB. Rather, replication of ICEBs1 required the helicase PcrA that is required for rolling circle replication of many plasmids. Transfer of ICEBs1 from the donor required PcrA, but did not require replication, indicating that PcrA, and not DNA replication, facilitates unwinding of ICEBs1 DNA for horizontal transfer. Although not needed for horizontal transfer, replication of ICEBs1 was needed for stability of the element. We propose that autonomous plasmid-like replication is a common property of ICEs and contributes to the stability and maintenance of these mobile genetic elements in bacterial populations.National Institutes of Health (U.S.) (grant GM50895

    The Bacillus subtilis conjugative transposon ICEBs1 mobilizes plasmids lacking dedicated mobilization functions

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    Integrative and conjugative elements (ICEs, also known as conjugative transposons) are mobile elements that are found integrated in a host genome and can excise and transfer to recipient cells via conjugation. ICEs and conjugative plasmids are found in many bacteria and are important agents of horizontal gene transfer and microbial evolution. Conjugative elements are capable of self-transfer and also capable of mobilizing other DNA elements that are not able to self-transfer. Plasmids that can be mobilized by conjugative elements are generally thought to contain an origin of transfer (oriT), from which mobilization initiates, and to encode a mobilization protein (Mob, a relaxase) that nicks a site in oriT and covalently attaches to the DNA to be transferred. Plasmids that do not have both an oriT and a cognate mob are thought to be nonmobilizable. We found that Bacillus subtilis carrying the integrative and conjugative element ICEBs1 can transfer three different plasmids to recipient bacteria at high frequencies. Strikingly, these plasmids do not have dedicated mobilization-oriT functions. Plasmid mobilization required conjugation proteins of ICEBs1, including the putative coupling protein. In contrast, plasmid mobilization did not require the ICEBs1 conjugative relaxase or cotransfer of ICEBs1, indicating that the putative coupling protein likely interacts with the plasmid replicative relaxase and directly targets the plasmid DNA to the ICEBs1 conjugation apparatus. These results blur the current categorization of mobilizable and nonmobilizable plasmids and indicate that conjugative elements play a role in horizontal gene transfer even more significant than previously recognized.National Institutes of Health (U.S.) (Grant GM50895

    Intravenous Vitamin C Administered as Adjunctive Therapy for Recurrent Acute Respiratory Distress Syndrome

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    This case report summarizes the first use of intravenous vitamin C employed as an adjunctive interventional agent in the therapy of recurrent acute respiratory distress syndrome (ARDS). The two episodes of ARDS occurred in a young female patient with Cronkhite-Canada syndrome, a rare, sporadically occurring, noninherited disorder that is characterized by extensive gastrointestinal polyposis and malabsorption. Prior to the episodes of sepsis, the patient was receiving nutrition via chronic hyperalimentation administered through a long-standing central venous catheter. The patient became recurrently septic with Gram positive cocci which led to two instances of ARDS. This report describes the broad-based general critical care of a septic patient with acute respiratory failure that includes fluid resuscitation, broad-spectrum antibiotics, and vasopressor support. Intravenous vitamin C infused at 50 mg per kilogram body weight every 6 hours for 96 hours was incorporated as an adjunctive agent in the care of this patient. Vitamin C when used as a parenteral agent in high doses acts “pleiotropically” to attenuate proinflammatory mediator expression, to improve alveolar fluid clearance, and to act as an antioxidant

    A conserved helicase processivity factor is needed for conjugation and replication of an integrative and conjugative element

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    Integrative and conjugative elements (ICEs) are agents of horizontal gene transfer and have major roles in evolution and acquisition of new traits, including antibiotic resistances. ICEs are found integrated in a host chromosome and can excise and transfer to recipient bacteria via conjugation. Conjugation involves nicking of the ICE origin of transfer (oriT) by the ICE–encoded relaxase and transfer of the nicked single strand of ICE DNA. For ICEBs1 of Bacillus subtilis, nicking of oriT by the ICEBs1 relaxase NicK also initiates rolling circle replication. This autonomous replication of ICEBs1 is critical for stability of the excised element in growing cells. We found a conserved and previously uncharacterized ICE gene that is required for conjugation and replication of ICEBs1. Our results indicate that this gene, helP (formerly ydcP), encodes a helicase processivity factor that enables the host-encoded helicase PcrA to unwind the double-stranded ICEBs1 DNA. HelP was required for both conjugation and replication of ICEBs1, and HelP and NicK were the only ICEBs1 proteins needed for replication from ICEBs1 oriT. Using chromatin immunoprecipitation, we measured association of HelP, NicK, PcrA, and the host-encoded single-strand DNA binding protein Ssb with ICEBs1. We found that NicK was required for association of HelP and PcrA with ICEBs1 DNA. HelP was required for association of PcrA and Ssb with ICEBs1 regions distal, but not proximal, to oriT, indicating that PcrA needs HelP to progress beyond nicked oriT and unwind ICEBs1. In vitro, HelP directly stimulated the helicase activity of the PcrA homologue UvrD. Our findings demonstrate that HelP is a helicase processivity factor needed for efficient unwinding of ICEBs1 for conjugation and replication. Homologues of HelP and PcrA-type helicases are encoded on many known and putative ICEs. We propose that these factors are essential for ICE conjugation, replication, and genetic stability.National Institutes of Health (U.S.) (Grant GM50895

    Giving to Government: Voluntary Taxation in the Lab

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    In the United States, there is widespread antipathy toward taxation, yet at the same time there are substantial voluntary donations to nonprofit organizations with missions that are parallel to those of many government agencies. In this paper we compare giving in the form of voluntary taxes paid to government agencies with giving in the form of voluntary donations to nonprofit organizations that have similar missions. In a laboratory experimental setting, subjects are given an endowment, and are given the opportunity to donate any part of the endowment to a government agency or to a nonprofit organization. We compare levels of giving to private and government organizations for four different causes (cancer research, disaster relief, education, and parks and wildlife) at three levels of government (federal, state and local). Within a session, subjects make 12 decisions: they complete all six separate decisions for each of two causes, selected randomly from the four listed above. We find that people are not averse to giving to government. On average, they give 22 percent of their budget to government when anonymity is ensured and giving is completely voluntary. However, they do show a preference for nonprofit charities by giving higher amounts for most causes and levels of government. The willingness to give is influenced by the cause and level of the organization, as well as perceptions of the organization

    Modulation of the ComA-Dependent Quorum Response in \u3ci\u3eBacillus subtilis\u3c/i\u3e by Multiple Rap Proteins and Phr Peptides

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    In Bacillus subtilis, extracellular peptide signaling regulates several biological processes. Secreted Phr signaling peptides are imported into the cell and act intracellularly to antagonize the activity of regulators known as Rap proteins. B. subtilis encodes several Rap proteins and Phr peptides, and the processes regulated by many of these Rap proteins and Phr peptides are unknown. We used DNA microarrays to characterize the roles that several rap-phr signaling modules play in regulating gene expression. We found that rapK-phrK regulates the expression of a number of genes activated by the response regulator ComA. ComA activates expression of genes involved in competence development and the production of several secreted products. Two Phr peptides, PhrC and PhrF, were previously known to stimulate the activity of ComA. We assayed the roles that PhrC, PhrF, and PhrK play in regulating gene expression and found that these three peptides stimulate ComA-dependent gene expression to different levels and are all required for full expression of genes activated by ComA. The involvement of multiple Rap proteins and Phr peptides allows multiple physiological cues to be integrated into a regulatory network that modulates the timing and magnitude of the ComA response

    Polar positioning of a conjugation protein from the integrative and conjugative element ICEBs1 of Bacillus subtilis

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    ICEBs1 is an integrative and conjugative element found in the chromosome of Bacillus subtilis. ICEBs1 encodes functions needed for its excision and transfer to recipient cells. We found that the ICEBs1 gene conE (formerly yddE) is required for conjugation and that conjugative transfer of ICEBs1 requires a conserved ATPase motif of ConE. ConE belongs to the HerA/FtsK superfamily of ATPases, which includes the well-characterized proteins FtsK, SpoIIIE, VirB4, and VirD4. We found that a ConE-GFP (green fluorescent protein) fusion associated with the membrane predominantly at the cell poles in ICEBs1 donor cells. At least one ICEBs1 product likely interacts with ConE to target it to the membrane and cell poles, as ConE-GFP was dispersed throughout the cytoplasm in a strain lacking ICEBs1. We also visualized the subcellular location of ICEBs1. When integrated in the chromosome, ICEBs1 was located near midcell along the length of the cell, a position characteristic of that chromosomal region. Following excision, ICEBs1 was more frequently found near a cell pole. Excision of ICEBs1 also caused altered positioning of at least one component of the replisome. Taken together, our findings indicate that ConE is a critical component of the ICEBs1 conjugation machinery, that conjugative transfer of ICEBs1 from B. subtilis likely initiates at a donor cell pole, and that ICEBs1 affects the subcellular position of the replisome.Public Health Service (grant GM50895 (A.D.G.))Suffolk University. Department of Chemistry and Biochemistr
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