4,888 research outputs found

    An unusual presentation of leishmaniasis in a human immunodeficiency virus-positive individual

    Get PDF
    INTRODUCTION: Leishmaniasis is a neglected tropical disease caused by vector-borne protozoa of the genus Leishmania. Cutaneous and mucocutaneous forms result in disfiguration or mutilation, whilst visceral leishmaniasis (VL) affects multiple organs and is fatal if untreated. Notably, Leishmania are capable of establishing a chronic infection, which may reactivate years after initial infection when the host becomes immune-suppressed. CASE PRESENTATION: A 24-year-old human immunodeficiency virus (HIV)-positive male presented for excision of anal condylomas. At the time of his current condyloma excision, the patient had no additional symptoms or cutaneous findings, but was noted to have been only intermittently compliant with his antiretroviral therapy. Microscopic examination of the haematoxylin and eosin-stained anal condyloma tissue revealed koilocytic change, ulceration and brisk histiocytic inflammation containing numerous small intracellular bodies suggestive of Leishmania amastigotes. A bone marrow biopsy was performed and demonstrated similar intracellular forms. Anal condyloma tissue and bone marrow aspirate were sent to the Centers for Disease Control and Prevention's Parasitic Diseases Branch for confirmation of Leishmania and speciation. Specific immunohistochemical staining for Leishmania in the tissue section was positive and the species was confirmed as Leishmania donovani by PCR. Subsequently, the patient resumed highly active antiretroviral therapy and received anti-Leishmania therapy. CONCLUSION: Whilst the presentation of VL in HIV-positive patients is often similar to those without HIV, here we describe an unusual initial presentation of leishmaniasis in an HIV-positive patient where the parasite was found in an anal condyloma. VL is a critical diagnosis that should be considered and pursued when leishmaniasis is encountered in seemingly illogical clinical settings

    The Role of Deontic Logic in the Specification of Information Systems

    Get PDF
    In this paper we discuss the role that deontic logic plays in the specification of information systems, either because constraints on the systems directly concern norms or, and even more importantly, system constraints are considered ideal but violable (so-called `softÂż constraints).\ud To overcome the traditional problems with deontic logic (the so-called paradoxes), we first state the importance of distinguishing between ought-to-be and ought-to-do constraints and next focus on the most severe paradox, the so-called Chisholm paradox, involving contrary-to-duty norms. We present a multi-modal extension of standard deontic logic (SDL) to represent the ought-to-be version of the Chisholm set properly. For the ought-to-do variant we employ a reduction to dynamic logic, and show how the Chisholm set can be treated adequately in this setting. Finally we discuss a way of integrating both ought-to-be and ought-to-do reasoning, enabling one to draw conclusions from ought-to-be constraints to ought-to-do ones, and show by an example the use(fulness) of this

    Type IIb Supernova SN 2011dh: Spectra and Photometry from the Ultraviolet to the Near-Infrared

    Get PDF
    We report spectroscopic and photometric observations of the Type IIb SN 2011dh obtained between 4 and 34 days after the estimated date of explosion (May 31.5 UT). The data cover a wide wavelength range from 2,000 Angstroms in the UV to 2.4 microns in the NIR. Optical spectra provide line profiles and velocity measurements of HI, HeI, CaII and FeII that trace the composition and kinematics of the SN. NIR spectra show that helium is present in the atmosphere as early as 11 days after the explosion. A UV spectrum obtained with the STIS reveals that the UV flux for SN 2011dh is low compared to other SN IIb. The HI and HeI velocities in SN 2011dh are separated by about 4,000 km/s at all phases. We estimate that the H-shell of SN 2011dh is about 8 times less massive than the shell of SN 1993J and about 3 times more massive than the shell of SN 2008ax. Light curves (LC) for twelve passbands are presented. The maximum bolometric luminosity of 1.8±0.2×10421.8 \pm 0.2 \times 10^{42} erg s−1^{-1} occurred about 22 days after the explosion. NIR emission provides more than 30% of the total bolometric flux at the beginning of our observations and increases to nearly 50% of the total by day 34. The UV produces 16% of the total flux on day 4, 5% on day 9 and 1% on day 34. We compare the bolometric light curves of SN 2011dh, SN 2008ax and SN 1993J. The LC are very different for the first twelve days after the explosions but all three SN IIb display similar peak luminosities, times of peak, decline rates and colors after maximum. This suggests that the progenitors of these SN IIb may have had similar compositions and masses but they exploded inside hydrogen shells that that have a wide range of masses. The detailed observations presented here will help evaluate theoretical models for this supernova and lead to a better understanding of SN IIb.Comment: 23 pages, 14 figures, 9 tables, accepted by Ap

    The effects of maternal anxiety during pregnancy on IGF2/H19 methylation in cord blood

    Get PDF
    Compelling evidence suggests that maternal mental health in pregnancy can influence fetal development. The imprinted genes, insulin-like growth factor 2 (IGF2) and H19, are involved in fetal growth and each is regulated by DNA methylation. This study aimed to determine the association between maternal mental well-being during pregnancy and differentially methylated regions (DMRs) of IGF2 (DMR0) and the IGF2/H19 imprinting control region (ICR) in newborn offspring. Maternal depression, anxiety and perceived stress were assessed at 28 weeks of pregnancy in the Barwon Infant Study (n = 576). DNA methylation was measured in purified cord blood mononuclear cells using the Sequenom MassArray Platform. Maternal anxiety was associated with a decrease in average ICR methylation (Delta = -2.23%;95% CI = -3.68 to -0.77%), and across all six of the individual CpG units in anxious compared with non-anxious groups. Birth weight and sex modified the association between prenatal anxiety and infant methylation. When stratified into lower ( 3530 g) birth weight groups using the median birth weight, there was a stronger association between anxiety and ICR methylation in the lower birth weight group (Delta = -3.89%;95% CI = -6.06 to -1.72%), with no association in the higher birth weight group. When stratified by infant sex, there was a stronger association in female infants (Delta = -3.70%;95% CI = -5.90 to -1.51%) and no association in males. All the linear regression models were adjusted for maternal age, smoking and folate intake. These findings show that maternal anxiety in pregnancy is associated with decreased IGF2/H19 ICR DNA methylation in progeny at birth, particularly in female, low birth weight neonates. ICR methylation may help link poor maternal mental health and adverse birth outcomes, but further investigation is needed

    Spacesuit Range of Motion Investigations Using Video and Motion Capture Systems at Spaceflight Analogue Expeditions and within the ERAU S.U.I.T. Lab

    Get PDF
    The Embry-Riddle Aeronautical University (ERAU) Spacesuit Utilization of Innovative Technology Laboratory (S.U.I.T. Lab) is dedicated to the pursuit of advancing human spaceflight by contributing to spacesuit and operations research with experiential programs for students. A significant portion of the S.U.I.T. Lab’s portfolio is dedicated to the design and execution of spacesuit range of motion (ROM) investigations using video and motion capture systems. ROM biomechanical angles were measured using these techniques in conjunction with developing protocols for both simulated extravehicular activity suits at spaceflight analogue expeditions, and on ERAU campus with Final Frontier Design (FFD) intravehicular activity pressure suits. Designing protocols ensures effective communication for the analysis of simulated spacesuit performance to a remote crew. With communication delays to Earth, a self-sufficient spacesuit diagnosis is required to provide future astronauts with immediate action to take when dealing with a malfunctioning spacesuit. The video capture methodology is designed so that any crew would be able to conduct recordings with minimal impact to their schedule and with camera resources that are standard equipment. Spaceflight mission analogues involved in this study include: Hawai\u27i Space Exploration Analog and Simulation (HI-SEAS Mission V, 2017); Mars Desert Research Station (MDRS Crew 188, 2018), and AMADEE-18 in Oman (2018). Video capture can be used to collaborate with several spacesuit manufacturers to offer a snapshot comparison between designs, validate and verify capabilities, and aid with the selection of the right suit for the right job. The analogue locations recorded unsuited and suited data, while the November FFD test focused on motion capture (with video capture taken for validation) of unsuited, suited unpressurized, and suited while pressurized to 3.5 psid conditions. Early results from the motion capture align with values estimated from video capture and future work will compare the accuracy of these techniques

    Tracheotomy care simulation training program for inpatient providers

    Get PDF
    Objectives: Tracheotomy complications can be life-threatening. Many of these complications may be avoided with proper education of health care providers. Unfortunately, access to high-quality tracheotomy care curricula is limited. We developed a program to address this gap in tracheotomy care education for inpatient providers. This study aimed to assess the efficacy of this training program in improving trainee knowledge and comfort with tracheotomy care. Methods: The curriculum includes asynchronous online modules coupled with a self-directed hands-on simulation activity using a low-cost tracheotomy care task trainer. The program was offered to inpatient providers including medical students, residents, medical assistants, nurses, and respiratory therapists. Efficacy of the training was assessed using pre-training and post-training surveys of learner comfort, knowledge, and qualitative feedback. Results: Data was collected on 41 participants. After completing the program, participants exhibited significantly improved comfort in performing tracheotomy care activities and 15% improvement in knowledge scores, with large effect sizes respectively and greater gains among those with little prior tracheotomy care experience. Conclusion: This study has demonstrated that completion of this integrated online and hands-on tracheotomy simulation curriculum training increases comfort and knowledge, especially for less-experienced learners. This training addresses an important gap in tracheotomy care education among health care professionals with low levels of tracheotomy care experience and ultimately aims to improve patient safety and quality of care. This curriculum is easily transferrable as it requires only access to the online modules and low-cost simulation materials and could be used in other hospitals, long-term care facilities, outpatient clinics, and home settings

    Intergalactic HII Regions Discovered in SINGG

    Get PDF
    A number of very small isolated HII regions have been discovered at projected distances up to 30 kpc from their nearest galaxy. These HII regions appear as tiny emission line objects in narrow band images obtained by the NOAO Survey for Ionization in Neutral Gas Galaxies (SINGG). We present spectroscopic confirmation of four isolated HII regions in two systems, both systems have tidal HI features. The results are consistent with stars forming in interactive debris due to cloud-cloud collisions. The H-alpha luminosities of the isolated HII regions are equivalent to the ionizing flux of only a few O stars each. They are most likely ionized by stars formed in situ, and represent atypical star formation in the low density environment of the outer parts of galaxies. A small but finite intergalactic star formation rate will enrich and ionize the surrounding medium. In one system, NGC 1533, we calculate a star formation rate of 1.5e-3 msun/yr, resulting in a metal enrichment of ~1e-3 solar for the continuous formation of stars. Such systems may have been more common in the past and a similar enrichment level is measured for the `metallicity floor' in damped Lyman-alpha absorption systems.Comment: accepted for publication in the Astronomical Journal, 19 pages, including 5 figures, some low resolution. Paper with high resolution images can be downloaded from http://astro.ph.unimelb.edu.au/~eryan/publications/eldots.ps.g

    Pol II Docking and Pausing at Growth and Stress Genes in C. elegans

    Get PDF
    Fluctuations in nutrient availability profoundly impact gene expression. Previous work revealed postrecruitment regulation of RNA polymerase II (Pol II) during starvation and recovery in Caenorhabditis elegans, suggesting that promoter-proximal pausing promotes rapid response to feeding. To test this hypothesis, we measured Pol II elongation genome wide by two complementary approaches and analyzed elongation in conjunction with Pol II binding and expression. We confirmed bona fide pausing during starvation and also discovered Pol II docking. Pausing occurs at active stress-response genes that become downregulated in response to feeding. In contrast, “docked” Pol II accumulates without initiating upstream of inactive growth genes that become rapidly upregulated upon feeding. Beyond differences in function and expression, these two sets of genes have different core promoter motifs, suggesting alternative transcriptional machinery. Our work suggests that growth and stress genes are both regulated postrecruitment during starvation but at initiation and elongation, respectively, coordinating gene expression with nutrient availability

    The Survey for Ionization in Neutral Gas Galaxies- II. The Star Formation Rate Density of the Local Universe

    Full text link
    We derive observed Halpha and R band luminosity densities of an HI-selected sample of nearby galaxies using the SINGG sample to be l_Halpha' = (9.4 +/- 1.8)e38 h_70 erg s^-1 Mpc^-3 for Halpha and l_R' = (4.4 +/- 0.7)e37 h_70 erg s^-1 A^-1 Mpc^-3 in the R band. This R band luminosity density is approximately 70% of that found by the Sloan Digital Sky Survey. This leads to a local star formation rate density of log(SFRD) = -1.80 +0.13/-0.07(random) +/- 0.03(systematic) + log(h_70) after applying a mean internal extinction correction of 0.82 magnitudes. The gas cycling time of this sample is found to be t_gas = 7.5 +1.3/-2.1 Gyr, and the volume-averaged equivalent width of the SINGG galaxies is EW(Halpha) = 28.8 +7.2/-4.7 A (21.2 +4.2/-3.5 A without internal dust correction). As with similar surveys, these results imply that SFRD(z) decreases drastically from z ~ 1.5 to the present. A comparison of the dynamical masses of the SINGG galaxies evaluated at their optical limits with their stellar and HI masses shows significant evidence of downsizing: the most massive galaxies have a larger fraction of their mass locked up in stars compared with HI, while the opposite is true for less massive galaxies. We show that the application of the Kennicutt star formation law to a galaxy having the median orbital time at the optical limit of this sample results in a star formation rate decay with cosmic time similar to that given by the SFRD(z) evolution. This implies that the SFRD(z) evolution is primarily due to the secular evolution of galaxies, rather than interactions or mergers. This is consistent with the morphologies predominantly seen in the SINGG sample.Comment: 15 pages, 5 figures, ApJ in press. Data available at http://sungg.pha.jhu.edu/PubData/ Corrected: Minor typos and formatting issues fixe

    The Survey for Ionization in Neutral Gas Galaxies: I. Description and Initial Results

    Get PDF
    We introduce the Survey for Ionization in Neutral Gas Galaxies (SINGG), a census of star formation in HI-selected galaxies. The survey consists of H-alpha and R-band imaging of a sample of 468 galaxies selected from the HI Parkes All Sky Survey (HIPASS). The sample spans three decades in HI mass and is free of many of the biases that affect other star forming galaxy samples. We present the criteria for sample selection, list the entire sample, discuss our observational techniques, and describe the data reduction and calibration methods. This paper focuses on 93 SINGG targets whose observations have been fully reduced and analyzed to date. The majority of these show a single Emission Line Galaxy (ELG). We see multiple ELGs in 13 fields, with up to four ELGs in a single field. All of the targets in this sample are detected in H-alpha indicating that dormant (non-star forming) galaxies with M(HI) > ~3e7 M_sun are very rare. A database of the measured global properties of the ELGs is presented. The ELG sample spans four orders of magnitude in luminosity (H-alpha and R-band), and H-alpha surface brightness, nearly three orders of magnitude in R surface brightness and nearly two orders of magnitude in H-alpha equivalent width (EW). The surface brightness distribution of our sample is broader than that of the Sloan Digital Sky Survey spectroscopic sample, the (EW) distribution is broader than prism-selected samples, and the morphologies found include all common types of star forming galaxies (e.g. irregular, spiral, blue compact dwarf, starbursts, merging and colliding systems, and even residual star formation in S0 and Sa spirals). (abridged)Comment: 28 pages, ApJS, in press. Full resolution version with all panels of Fig. 8 available at http://sungg.pha.jhu.edu/publications.html . On line data available at http://sungg.pha.jhu.edu/PubData/ . Author list corrected. Wrong value for f_ap used in eq. 7 now corrected; typos corrected, non-used references replaced, others update
    • 

    corecore