1,162 research outputs found

    Conserved noncoding sequences highlight shared components of regulatory networks in dicotyledonous plants

    Get PDF
    Conserved noncoding sequences (CNSs) in DNA are reliable pointers to regulatory elements controlling gene expression. Using a comparative genomics approach with four dicotyledonous plant species (Arabidopsis thaliana, papaya [Carica papaya], poplar [Populus trichocarpa], and grape [Vitis vinifera]), we detected hundreds of CNSs upstream of Arabidopsis genes. Distinct positioning, length, and enrichment for transcription factor binding sites suggest these CNSs play a functional role in transcriptional regulation. The enrichment of transcription factors within the set of genes associated with CNS is consistent with the hypothesis that together they form part of a conserved transcriptional network whose function is to regulate other transcription factors and control development. We identified a set of promoters where regulatory mechanisms are likely to be shared between the model organism Arabidopsis and other dicots, providing areas of focus for further research

    ALMA Multi-line Imaging of the Nearby Starburst Galaxy NGC 253

    Full text link
    We present spatially resolved (\sim50 pc) imaging of molecular gas species in the central kiloparsec of the nearby starburst galaxy NGC 253, based on observations taken with the Atacama Large Millimeter/submillimeter Array (ALMA). A total of 50 molecular lines are detected over a 13 GHz bandwidth imaged in the 3 mm band. Unambiguous identifications are assigned for 27 lines. Based on the measured high CO/C17^{17}O isotopic line ratio (\gtrsim350), we show that 12^{12}CO(1-0) has moderate optical depths. A comparison of the HCN and HCO+^{+} with their 13^{13}C-substituted isotopologues shows that the HCN(1-0) and HCO+^{+}(1-0) lines have optical depths at least comparable to CO(1-0). H13^{13}CN/H13^{13}CO+^{+} (and H13^{13}CN/HN13^{13}C) line ratios provide tighter constraints on dense gas properties in this starburst. SiO has elevated abundances across the nucleus. HNCO has the most distinctive morphology of all the bright lines, with its global luminosity dominated by the outer parts of the central region. The dramatic variation seen in the HNCO/SiO line ratio suggests that some of the chemical signatures of shocked gas are being erased in the presence of dominating central radiation fields (traced by C2_{2}H and CN). High density molecular gas tracers (including HCN, HCO+^+, and CN) are detected at the base of the molecular outflow. We also detect hydrogen β\beta recombination lines that, like their α\alpha counterparts, show compact, centrally peaked morphologies, distinct from the molecular gas tracers. A number of sulfur based species are mapped (CS, SO, NS, C2_{2}S, H2_{2}CS and CH3_{3}SH) and have morphologies similar to SiO.Comment: 20 pages, 10 figures, accepted to the Astrophysical Journa

    Arnol'd Tongues and Quantum Accelerator Modes

    Full text link
    The stable periodic orbits of an area-preserving map on the 2-torus, which is formally a variant of the Standard Map, have been shown to explain the quantum accelerator modes that were discovered in experiments with laser-cooled atoms. We show that their parametric dependence exhibits Arnol'd-like tongues and perform a perturbative analysis of such structures. We thus explain the arithmetical organisation of the accelerator modes and discuss experimental implications thereof.Comment: 20 pages, 6 encapsulated postscript figure

    Nutritional Transition of Riverine People from Puruzinho Lake in the Amazon Region. A Qualitative Study

    Full text link
    Scientific studies suggest that eating habits of traditional communities all over the world have been suffering changes as a result of gradual replacement of regional products with imported ones and also because of the increase of consumption of carbohydrates and trans fats. The nutritional state of populations, as riverine people in the Amazon region, has been widely affected by factors as changes in the eating and epidemiologic patterns. This study aims at the identification of the perception of dwellers of a riverine community the Brazilian Amazon region on their eating habits, their health and on the changes caused by development. This is a qualitative study, in which we used ethnographic semi structured interviews as a tool to collect data, conducted through a semi structured script, and applied to 16 dwellers/heads of families, in which 11 are men and 5 are women. The interviews were recorded in audio, full text transcribed and analyzed, and resulted in a descriptive system of categories and subcategories. As a result, we identified an increase of purchase capacity, greater participation in the market economy, lack of effective and continuous actions by the administrators of basic health services in the city. These joint factors contribute to the process of nutritional transition that is occurring in the community, as well as to the increase of health vulnerability of the dwellers

    Discovery Learning: Development of a Unique Active Learning Environment for Introductory Chemistry

    Get PDF
    It is well established that active learning results in greater gains in student conceptual knowledge and retention compared to traditional modes of learning.  However, active learning can be very difficult to implement in a large-enrollment course due to various course and institutional barriers.  Herein, we describe the development and implementation of Discovery Learning, a novel active learning discussion/recitation for a large enrollment general chemistry course.  Drawing on the very successful cooperative learning pedagogies Process-Oriented Guided Inquiry Learning (POGIL) and Student-Centered Active Learning Environment with Upside-down Pedagogies (SCALE_UP), Discovery Learning involves students working in self-managed teams on inquiry problems in a unique learning environment, the Chemistry Discovery Center.  In this case study, we will describe the design and implementation of Discovery Learning and report data on its successes, which include increased student performance and retention

    Nonlinearity effects in the kicked oscillator

    Full text link
    The quantum kicked oscillator is known to display a remarkable richness of dynamical behaviour, from ballistic spreading to dynamical localization. Here we investigate the effects of a Gross Pitaevskii nonlinearity on quantum motion, and provide evidence that the qualitative features depend strongly on the parameters of the system.Comment: 4 pages, 5 figure

    Improving Nursing Facility Care Through an Innovative Payment Demonstration Project: Optimizing Patient Transfers, Impacting Medical Quality, and Improving Symptoms: Transforming Institutional Care Phase 2

    Get PDF
    Optimizing Patient Transfers, Impacting Medical Quality, and Improving Symptoms: Transforming Institutional Care (OPTIMISTIC) is a 2‐phase Center for Medicare and Medicaid Innovations demonstration project now testing a novel Medicare Part B payment model for nursing facilities and practitioners in 40 Indiana nursing facilities. The new payment codes are intended to promote high‐quality care in place for acutely ill long‐stay residents. The focus of the initiative is to reduce hospitalizations through the diagnosis and on‐site management of 6 common acute clinical conditions (linked to a majority of potentially avoidable hospitalizations of nursing facility residents1): pneumonia, urinary tract infection, skin infection, heart failure, chronic obstructive pulmonary disease or asthma, and dehydration. This article describes the OPTIMISTIC Phase 2 model design, nursing facility and practitioner recruitment and training, and early experiences implementing new Medicare payment codes for nursing facilities and practitioners. Lessons learned from the OPTIMISTIC experience may be useful to others engaged in multicomponent quality improvement initiatives

    The Safety of EXPAREL ® (Bupivacaine Liposome Injectable Suspension) Administered by Peripheral Nerve Block in Rabbits and Dogs

    Get PDF
    A sustained-release DepoFoam injection formulation of bupivacaine (EXPAREL, 15 mg/mL) is currently being investigated for postsurgical analgesia via peripheral nerve block (PNB). Single-dose toxicology studies of EXPAREL (9, 18, and 30 mg/kg), bupivacaine solution (Bsol, 9 mg/kg), and saline injected around the brachial plexus nerve bundle were performed in rabbits and dogs. The endpoints included clinical pathology, pharmacokinetics, and histopathology evaluation on Day 3 and Day 15 (2/sex/group/period). EXPAREL resulted in a nearly 4-fold lower Cmax versus Bsol at the same dose. EXPAREL was well tolerated at doses up to 30 mg/kg. The only EXPAREL-related effect seen was minimal to mild granulomatous inflammation of adipose tissue around nerve roots (8 of 24 rabbits and 7 of 24 dogs) in the brachial plexus sites. The results indicate that EXPAREL was well tolerated in these models and did not produce nerve damage after PNB in rabbits and dogs

    Safety Evaluation of EXPAREL (DepoFoam Bupivacaine) Administered by Repeated Subcutaneous Injection in Rabbits and Dogs: Species Comparison

    Get PDF
    EXPAREL (bupivacaine extended-release liposome injection), DepoFoam bupivacaine, is in development for prolonged postsurgical analgesia. Repeat-dose toxicity studies were conducted in rabbits and dogs to compare the potential local and systemic toxicities of EXPAREL and bupivacaine HCl (Bsol), and the reversibility of any effects. Dogs tolerated much larger doses than rabbits. EXPAREL-related minimal-to-moderate granulomatous inflammation was noted at the injection sites. In recovery animals, the granulomatous inflammation was observed less frequently and was characterized by an increased number of multinucleated giant cells. These effects were considered a normal response to liposomes and nonadverse. Rabbits are more sensitive than dogs. In rabbits, convulsions were noted with EXPAREL and more frequently with Bsol; a NOAEL was not identified. In dogs, EXPAREL was well tolerated (NOAEL > 30 mg/kg/dose). The cumulative exposure of EXPAREL in these studies is well in excess of the proposed maximum single-dose exposure that is intended in humans

    Attenuation of Acute Graft-versus-Host Disease in the Absence of the Transcription Factor ROR t

    Get PDF
    Graft-versus-host disease (GvHD) remains the most significant complication after allogeneic stem cell transplantation (allo-SCT). Previously, acute GvHD had been considered to be mediated predominantly by Th1 polarized T cells. Recently, investigators have identified a second pro-inflammatory lineage of T cells termed Th17 that is critically dependent on the transcription factor RORγt. Here, we have evaluated the role of Th17 cells in murine acute GvHD by infusing donor T cells lacking RORC and as a consequence the isoform RORγt. Recipients given donor CD4+ and CD8+ T cells lacking RORC had significantly attenuated acute GvHD and markedly decreased tissue pathology in the colon, liver, and lung. Using a clinically relevant haploidentical murine transplantation model, we showed that RORC−/− CD4+ T cells alone diminished the severity and lethality of aGvHD. This was not found when CD4+ T cells from RORC−/− mice were given to completely mismatched BALB/c mice, and correlated with absolute differences in the generation of TNF in the colon post transplant. Thus, CD4+ T cell expression of RORC is important in the pathogenesis of acute GVHD
    corecore