422 research outputs found

    Ultralong Copper Phthalocyanine Nanowires with New Crystal Structure and Broad Optical Absorption

    Full text link
    The development of molecular nanostructures plays a major role in emerging organic electronic applications, as it leads to improved performance and is compatible with our increasing need for miniaturisation. In particular, nanowires have been obtained from solution or vapour phase and have displayed high conductivity, or large interfacial areas in solar cells. In all cases however, the crystal structure remains as in films or bulk, and the exploitation of wires requires extensive post-growth manipulation as their orientations are random. Here we report copper phthalocyanine (CuPc) nanowires with diameters of 10-100 nm, high directionality and unprecedented aspect ratios. We demonstrate that they adopt a new crystal phase, designated eta-CuPc, where the molecules stack along the long axis. The resulting high electronic overlap along the centimetre length stacks achieved in our wires mediates antiferromagnetic couplings and broadens the optical absorption spectrum. The ability to fabricate ultralong, flexible metal phthalocyanine nanowires opens new possibilities for applications of these simple molecules

    Planned Cesarean or planned vaginal delivery for twins : secondary analysis of randomized controlled trial

    Get PDF
    ACKNOWLEDGMENTS We thank all the participants in the Twin Birth Study and the staff at the Centre for Mother, Infant, and Child Research for their hard work and dedication. The Twin Birth Study was supported by a grant (63164) from the Canadian Institute of Health Research. P.T. and M.H.Z. were supported by a grant from The Netherlands Organization for Scientific Research (NWO ‐ grant number 401.16.080). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Peer reviewedPublisher PD

    First Results from the COLA Project- the Radio-FIR Correlation and Compact Radio Cores in Southern COLA Galaxies

    Get PDF
    We present the first results from the COLA (Compact Objects in Low-power AGN) project which aims to determine the relationship between one facet of AGN activity, the compact radio core, with star formation in the circumnuclear region of the host galaxy. This will be accomplished by the comparison of the multi-wavelength properties of a sample of AGN with compact radio cores to those of a sample of AGN without compact cores and a matched sample of galaxies without AGN. In this paper we discuss the selection criteria for our galaxy samples and present the initial radio observations of the 107 Southern galaxies in our sample. Low-resolution ATCA observations at 4.8, 2.5 and 1.4 GHz and high resolution, single baseline snapshots at 2.3 GHz with the Australian LBA are presented. We find that for the majority of the galaxies in our sample, the radio luminosity is correlated with the FIR luminosity. Compact radio cores are detected in 9 galaxies. The majority (8/9) of these galaxies exhibit a significant radio excess and 50% (7/14) of the galaxies which lie above the radio-FIR correlation by more than 1 sigma have compact radio cores. The emission from the cores is too weak to account for this radio excess and there is no evidence that the radio luminosity of the compact cores is correlated with the FIR galaxy luminosity. The galaxies with compact cores tend to be classified optically as AGN, with two thirds (6/9) exhibiting Seyfert-like optical emission line ratios, and the remaining galaxies classified either as composite objects (2/9) or starburst (1/9). (Abridged)Comment: 25 pages, including 6 figures and 4 tables, in Latex (uses emulateapj5.sty). Accepted for publication in Ap

    Vitamin D in the general population of young adults with autism in the Faroe Islands

    Get PDF
    Vitamin D deficiency has been proposed as a possible risk factor for developing autism spectrum disorder (ASD). 25-Hydroxyvitamin D3 (25(OH)D3) levels were examined in a cross-sectional population-based study in the Faroe Islands. The case group consisting of a total population cohort of 40 individuals with ASD (aged 15–24 years) had significantly lower 25(OH)D3 than their 62 typically-developing siblings and their 77 parents, and also significantly lower than 40 healthy age and gender matched comparisons. There was a trend for males having lower 25(OH)D3 than females. Effects of age, month/season of birth, IQ, various subcategories of ASD and Autism Diagnostic Observation Schedule score were also investigated, however, no association was found. The very low 25(OH)D3 in the ASD group suggests some underlying pathogenic mechanism

    In Digital We Trust: The Computerisation of Retail Finance in Western Europe and North America

    Get PDF
    This paper tells of the contents of a forthcoming volume, which offers a new and original approach to the study of technological change in retail finance. Most business history studies of businesses for the last 50 years note the emergence of computers and computer applications, but they do not analyze their role in shaping business practices and organizations. In this book we look directly at the processes of mechanisation and computerisation of retail financial services, throughout the 20th Century while articulating an international comparison. We bring together young, well established and independent historians, who come from different traditions (that is, economic, business, accounting, geography and political histories as well as historians of technology). Contributors look at stand alone and comparative case studies from different parts of the world (namely Britain, Denmark, France, Germany, Netherlands, Spain, Sweden, Mexico and the USA). The outcome is a rich survey of the broad literature examining different aspects of the technological and business histories of retail financial markets from a variety of perspectives

    Planned Cesarean or planned vaginal delivery for twins: secondary analysis of randomized controlled trial

    Get PDF
    Objective: To evaluate whether there is a differential benefit of planned Cesarean delivery (CD) over planned vaginal delivery (VD) in women with a twin pregnancy and the first twin in cephalic presentation, depending on prespecified baseline maternal and pregnancy characteristics, and/or gestational age (GA) at delivery. Methods: This was a secondary analysis of the Twin Birth Study, which included 2804 women with a twin pregnancy and the first twin (Twin A) in cephalic presentation between 32 + 0 and 38 + 6 weeks\u27 gestation at 106 centers in 25 countries. Women were assigned randomly to either planned CD or planned VD. The main outcome measure was composite adverse perinatal outcome, defined as the occurrence of perinatal mortality or serious neonatal morbidity in at least one twin. The baseline maternal and pregnancy characteristics (markers) considered were maternal age, parity, history of CD, use of antenatal corticosteroids, estimated fetal weight (EFW) of Twin A, EFW of Twin B, \u3e 25% difference in EFW between the twins, presentation of Twin B, chorionicity on ultrasound, method of conception, complications of pregnancy, ruptured membranes at randomization and GA at randomization. Separate logistic regression models were developed for each marker in order to model composite adverse perinatal outcome as a function of the specific marker, planned delivery mode and the interaction between these two terms. In addition, multivariable logistic regression analysis with backward variable elimination was performed separately in each arm of the trial. The association between planned mode of delivery and composite adverse perinatal outcome, according to GA at delivery, was assessed using logistic regression analysis. Results: Of the 2804 women initially randomized, 1391 were included in each study arm. None of the studied baseline markers was associated with a differential benefit of planned CD over planned VD in the rate of composite adverse perinatal outcome. GA at delivery was associated differentially with composite adverse perinatal outcome in the treatment arms (P for interaction \u3c 0.001). Among pregnancies delivered at 32 + 0 to 36 + 6 weeks, there was a trend towards a lower rate of composite adverse perinatal outcome in those in the planned-VD group compared with those in planned-CD group (29 (2.2%) vs 48 (3.6%) cases; odds ratio (OR) 0.62 (95% CI, 0.37–1.03)). In pregnancies delivered at or after 37 + 0 weeks, planned VD was associated with a significantly higher rate of composite adverse perinatal outcome, as compared with planned CD (23 (1.5%) vs 10 (0.7%) cases; OR, 2.25 (95% CI, 1.06–4.77)). Conclusion: The perinatal outcome of twin pregnancies with the first twin in cephalic presentation may differ depending on GA at delivery and planned mode of delivery. At 32–37 weeks, planned VD seems to be favorable, while, from around 37 weeks onwards, planned CD might be safer. The absolute risks of adverse perinatal outcomes at term are low and must be weighed against the increased maternal risks associated with planned CD. © 2019 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology

    Racial-Ethnic Disparities in Acute Stroke Care in the Florida-Puerto Rico Collaboration to Reduce Stroke Disparities Study

    Get PDF
    Background-Racial-ethnic disparities in acute stroke care can contribute to inequality in stroke outcomes. We examined raceethnic disparities in acute stroke performance metrics in a voluntary stroke registry among Florida and Puerto Rico Get With the Guidelines-Stroke hospitals. Methods and Results-Seventy-five sites in the Florida Puerto Rico Stroke Registry (66 Florida and 9 Puerto Rico) recorded 58 864 ischemic stroke cases (2010-2014). Logistic regression models examined racial-ethnic differences in acute stroke performance measures and defect-free care (intravenous tissue plasminogen activator treatment, in-hospital antithrombotic therapy, deep vein thrombosis prophylaxis, discharge antithrombotic therapy, appropriate anticoagulation therapy, statin use, smoking cessation counseling) and temporal trends. Among ischemic stroke cases, 63% were non-Hispanic white (NHW), 18% were non-Hispanic black (NHB), 14% were Hispanic living in Florida, and 6% were Hispanic living in Puerto Rico. NHW patients were the oldest, followed by Hispanics, and NHBs. Defect-free care was greatest among NHBs (81%), followed by NHWs (79%) and Florida Hispanics (79%), then Puerto Rico Hispanics (57%) (P \u3c 0.0001). Puerto Rico Hispanics were less likely than Florida whites to meet any stroke care performance metric other than anticoagulation. Defect-free care improved for all groups during 2010-2014, but the disparity in Puerto Rico persisted (2010: NHWs=63%, NHBs=65%, Florida Hispanics=59%, Puerto Rico Hispanics=31%; 2014: NHWs=93%, NHBs=94%, Florida Hispanics=94%, Puerto Rico Hispanics=63%). Conclusions-Racial-ethnic/geographic disparities were observed for acute stroke care performance metrics. Adoption of a quality improvement program improved stroke care from 2010 to 2014 in Puerto Rico and all Florida racial-ethnic groups. However, stroke care quality delivered in Puerto Rico is lower than in Florida. Sustained support of evidence-based acute stroke quality improvement programs is required to improve stroke care and minimize racial-ethnic disparities, particularly in resource-strained Puerto Rico

    Multi organ assessment of compensated cirrhosis patients using quantitative magnetic resonance imaging

    Get PDF
    Background and Aims: Advancing liver disease results in deleterious changes in a number of critical organs. The ability to measure structure, blood flow and tissue perfusion within multiple organs in a single scan has implications for determining the balance of benefit versus harm for therapies. Our aim was to establish the feasibility of Magnetic Resonance Imaging to assess changes in compensated cirrhosis (CC), and relate this to disease severity and future liver related outcomes (LROs). Methods: 60 CC patients, 40 healthy volunteers and 7 decompensated cirrhotics were recruited. In a single scan session, MRI measures comprised phase-contrast MRI vessel blood flow, arterial spin labelling tissue perfusion, T1 longitudinal relaxation time and volume assessment of liver, spleen and kidneys, heart rate and cardiac index. We explore MRI parameters with disease severity and differences in baseline MRI parameters in those 11 (18%) of CC patients who had future LROs. Results: In the liver compositional changes were reflected by increased T1 in progressive disease (p<0.001) and an increase in liver volume in CC (p=0.006), with associated progressive reduction in liver (p < 0.001) and splenic (p<0.001) perfusion. A significant reduction in renal cortex T1 and increase in cardiac index and superior mesenteric arterial (SMA) blood flow was seen with increasing disease severity. Baseline liver T1 (p=0.01) and perfusion (p< 0.01), and renal cortex T1 (p<0.01) were significantly different in CC patients who subsequently developed negative LROs. Conclusions: MRI allows the contemporaneous assessment of organs in liver cirrhosis in a single scan without the requirement of contrast agent. MRI parameters of liver T1, renal T1, hepatic and splenic perfusion, and SMA blood flow were related to risk of LROs
    corecore