583 research outputs found

    Polychaetes (Perinereis helleri) reared in sand beds filtering nutrients from shrimp (Penaeus monodon) culture ponds can transiently carry IHHNV

    Get PDF
    A polychaete-assisted sand filter (PASF) system has been developed to help remove nutrients from aquaculture pond wastewater whilst also producing polychaetes that are highly prized as bait by recreational anglers and as a dietary supplement to improve the fecundity of shrimp broodstock. Whilst rearing polychaetes in PASF beds offers potential to reduce impacts of sourcing them from the wild, the use of wastewater from ponds rearing shrimp such as Penaeus monodon will present a biosecurity risk of viruses being transferred to, and potentially amplified in, the worms. To assess such risks for transmitting infectious hypodermal and haematopoietic necrosis virus (IHHNV), groups of 3 or 4 PASF beds seeded with sand worm (Perinereis helleri) juveniles were supplied with wastewater from ponds of P. monodon with either high-load or low-load IHHNV infections. TaqMan real-time qPCR identified low loads of IHHNV (≤878 IHHNV DNA copies 200 ng−1 TNA) in most worms from PASF beds supplied wastewater from the high-load pond. IHHNV was either not detected or detected at the qPCR test sensitivity limits in worms from beds supplied wastewater from the low-load pond. Purging harvested worms of their gut contents in clean filtered seawater for 2 days significantly reduced IHHNV loads. Reverting PASF beds to clean seawater for 8 weeks before harvest also significantly reduced worm loads of IHHNV. Daily additions of a commercial probiotic to the sand bed surface for 4 weeks prior to clean seawater application provided no discernible benefit to IHHNV clearance. While clearly demonstrated to be capable of carrying IHHNV, the remediation measures examined suggest potential to ameliorate the infection transmission risks of P. helleri reared in PASF beds supplied with shrimp pond wastewater as a nutrient source

    JWST reveals widespread CO ice and gas absorption in the Galactic Center cloud G0.253+0.016

    Full text link
    We report JWST NIRCam observations of G0.253+0.016, the molecular cloud in the Central Molecular Zone known as The Brick, with the F182M, F187N, F212N, F410M, F405N, and F466N filters. We catalog 56,146 stars detected in all 6 filters using the crowdsource package. Stars within and behind The Brick exhibit prodigious absorption in the F466N filter that is produced by a combination of CO ice and gas. In support of this conclusion, and as a general resource, we present models of CO gas and ice and CO2_2 ice in the F466N, F470N, and F410M filters. Both CO gas and ice may contribute to the observed stellar colors. We show, however, that CO gas does not absorb the Pfβ\beta and Huϵ\epsilon lines in F466N, but that these lines show excess absorption, indicating that CO ice is also present and contributes to observed F466N absorption. The most strongly absorbed stars in F466N are extincted by \sim 2 magnitudes, corresponding to >> 80\% flux loss. This high observed absorption requires very high column densities of CO, requiring total CO column that is in tension with standard CO abundance and/or gas-to-dust ratios. There is therefore likely to be a greater CO/H2_2 ratio (XCO>104_{CO} > 10^{-4}) and more dust per H2_2 molecule (>0.01>0.01) in the Galactic Center than the Galactic disk. Ice and/or gas absorption is observed even in the cloud outskirts, implying that additional caution is needed when interpreting stellar photometry in filters that overlap with ice bands throughout our Galactic Center. The widespread CO absorption in our Galactic Center hints that significant ice absorption is likely present in other galactic centers.Comment: Submitted to ApJ. Revised after second referee report. 16 pages, 11 figure

    Decoherence and Programmable Quantum Computation

    Get PDF
    An examination of the concept of using classical degrees of freedom to drive the evolution of quantum computers is given. Specifically, when externally generated, coherent states of the electromagnetic field are used to drive transitions within the qubit system, a decoherence results due to the back reaction from the qubits onto the quantum field. We derive an expression for the decoherence rate for two cases, that of the single-qubit Walsh-Hadamard transform, and for an implementation of the controlled-NOT gate. We examine the impact of this decoherence mechanism on Grover's search algorithm, and on the proposals for use of error-correcting codes in quantum computation.Comment: submitted to Phys. Rev. A 35 double-spaced pages, 2 figures, in LaTe

    Automatic Quantum Error Correction

    Get PDF
    Criteria are given by which dissipative evolution can transfer populations and coherences between quantum subspaces, without a loss of coherence. This results in a form of quantum error correction that is implemented by the joint evolution of a system and a cold bath. It requires no external intervention and, in principal, no ancilla. An example of a system that protects a qubit against spin-flip errors is proposed. It consists of three spin 1/2 magnetic particles and three modes of a resonator. The qubit is the triple quantum coherence of the spins, and the photons act as ancilla.Comment: 16 pages 12 fig LaTex uses multicol, graphicx expanded version of letter submitted to Phys Rev Let

    Drug-induced liver injury associated with lopinavir-ritonavir in patients with COVID-19: a disproportionality analysis of U.S. food and drug administration adverse event reporting system (FAERS) data

    Get PDF
    Background Liver injury has been documented independently in novel coronavirus disease 2019 (COVID-19) patients and patients treated with lopinavir-ritonavir. Objective to investigate the drug-induced liver injury associated with lopinavir-ritonavir among the patients with COVID-19. Methods We conducted a disproportionality analysis of US Food and Drug Administration Adverse Event Reporting System (FAERS) between 2020Q1 and 2021Q1 to evaluate the association between lopinavir-ritonavir and risk of drug-induced liver injury (or severe drug-induced liver injury) and calculated their reporting odds ratios (RORs) with 95% confidence intervals (CIs). Results A total of 3,425 cases of drug-induced liver injury were reported in 19,782 patients with COVID-19. The ROR for drug-induced liver injury was 2.99 (2.59–3.46), 3.16 (2.68–3.73), and 5.39 (4.63–6.26) when comparing lopinavir-ritonavir with all other drugs, hydroxychloroquine/chloroquine only, and remdesivir, respectively. For severe drug-induced liver injury, RORs for lopinavir-ritonavir provided evidence of an association compared with all other drugs (3.98; 3.15–5.05), compared with hydroxychloroquine/chloroquine only (5.33; 4.09–6.94), and compared with remdesivir (3.85; 3.03–4.89). Conclusions In the FAERS, we observed a disproportional signal for drug-induced liver injury associated with lopinavir-ritonavir in patients with COVID-19

    Haloes gone MAD: The Halo-Finder Comparison Project

    Full text link
    [abridged] We present a detailed comparison of fundamental dark matter halo properties retrieved by a substantial number of different halo finders. These codes span a wide range of techniques including friends-of-friends (FOF), spherical-overdensity (SO) and phase-space based algorithms. We further introduce a robust (and publicly available) suite of test scenarios that allows halo finder developers to compare the performance of their codes against those presented here. This set includes mock haloes containing various levels and distributions of substructure at a range of resolutions as well as a cosmological simulation of the large-scale structure of the universe. All the halo finding codes tested could successfully recover the spatial location of our mock haloes. They further returned lists of particles (potentially) belonging to the object that led to coinciding values for the maximum of the circular velocity profile and the radius where it is reached. All the finders based in configuration space struggled to recover substructure that was located close to the centre of the host halo and the radial dependence of the mass recovered varies from finder to finder. Those finders based in phase space could resolve central substructure although they found difficulties in accurately recovering its properties. Via a resolution study we found that most of the finders could not reliably recover substructure containing fewer than 30-40 particles. However, also here the phase space finders excelled by resolving substructure down to 10-20 particles. By comparing the halo finders using a high resolution cosmological volume we found that they agree remarkably well on fundamental properties of astrophysical significance (e.g. mass, position, velocity, and peak of the rotation curve).Comment: 27 interesting pages, 20 beautiful figures, and 4 informative tables accepted for publication in MNRAS. The high-resolution version of the paper as well as all the test cases and analysis can be found at the web site http://popia.ft.uam.es/HaloesGoingMA

    GROWTH on S190510g: DECam Observation Planning and Follow-Up of a Distant Binary Neutron Star Merger Candidate

    Get PDF
    The first two months of the third Advanced LIGO and Virgo observing run (2019 April–May) showed that distant gravitational-wave (GW) events can now be readily detected. Three candidate mergers containing neutron stars (NS) were reported in a span of 15 days, all likely located more than 100 Mpc away. However, distant events such as the three new NS mergers are likely to be coarsely localized, which highlights the importance of facilities and scheduling systems that enable deep observations over hundreds to thousands of square degrees to detect the electromagnetic counterparts. On 2019 May 10 02:59:39.292 UT the GW candidate S190510g was discovered and initially classified as a binary neutron star (BNS) merger with 98% probability. The GW event was localized within an area of 3462 deg^2, later refined to 1166 deg^2 (90%) at a distance of 227 ± 92 Mpc. We triggered Target-of-Opportunity observations with the Dark Energy Camera (DECam), a wide-field optical imager mounted at the prime focus of the 4 m Blanco Telescope at Cerro Tololo Inter-American Observatory in Chile. This Letter describes our DECam observations and our real-time analysis results, focusing in particular on the design and implementation of the observing strategy. Within 24 hr of the merger time, we observed 65% of the total enclosed probability of the final skymap with an observing efficiency of 94%. We identified and publicly announced 13 candidate counterparts. S190510g was reclassified 1.7 days after the merger, after our observations were completed, with a "BNS merger" probability reduced from 98% to 42% in favor of a "terrestrial classification

    A Broad Line-width, Compact, Millimeter-bright Molecular Emission Line Source near the Galactic Center

    Get PDF
    A compact source, G0.02467-0.0727, was detected in Atacama Large Millimeter/submillimeter Array 3 mm observations in continuum and very broad line emission. The continuum emission has a spectral index α ≈ 3.3, suggesting that the emission is from dust. The line emission is detected in several transitions of CS, SO, and SO2 and exhibits a line width FWHM ≈ 160 km s−1. The line profile appears Gaussian. The emission is weakly spatially resolved, coming from an area on the sky ≲1′′ in diameter (≲104 au at the distance of the Galactic center, GC). The centroid velocity is v LSR ≈ 40-50 km s−1, which is consistent with a location in the GC. With multiple SO lines detected, and assuming local thermodynamic equilibrium (LTE) conditions, the gas temperature is T LTE = 13 K, which is colder than seen in typical GC clouds, though we cannot rule out low-density, subthermally excited, warmer gas. Despite the high velocity dispersion, no emission is observed from SiO, suggesting that there are no strong (≳10 km s−1) shocks in the molecular gas. There are no detections at other wavelengths, including X-ray, infrared, and radio. We consider several explanations for the millimeter ultra-broad-line object (MUBLO), including protostellar outflow, explosive outflow, a collapsing cloud, an evolved star, a stellar merger, a high-velocity compact cloud, an intermediate-mass black hole, and a background galaxy. Most of these conceptual models are either inconsistent with the data or do not fully explain them. The MUBLO is, at present, an observationally unique object

    The relationship between early neural responses to emotional faces at age 3 and later autism and anxiety symptoms in adolescents with autism

    Get PDF
    Both autism spectrum (ASD) and anxiety disorders are associated with atypical neural and attentional responses to emotional faces, differing in affective face processing from typically developing peers. Within a longitudinal study of children with ASD (23 male, 3 female), we hypothesized that early ERPs to emotional faces would predict concurrent and later ASD and anxiety symptoms. Greater response amplitude to fearful faces corresponded to greater social communication difficulties at age 3, and less improvement by age 14. Faster ERPs to neutral faces predicted greater ASD symptom improvement over time, lower ASD severity in adolescence, and lower anxiety in adolescence. Early individual differences in processing of emotional stimuli likely reflect a unique predictive contribution from social brain circuitry early in life

    A review of the integration of traditional, complementary and alternative medicine into the curriculum of South African medical schools

    Get PDF
    Background: Traditional, complementary and alternative (TCAM) medicine is consumed by a large majority of the South African population. In the context of increasing overall demand for healthcare this paper investigates the extent to which South African medical schools have incorporated TCAM into their curriculum because of the increased legislative and policy interest in formally incorporating TCAM into the health care system since democracy in 1994. Methods: Heads of School from seven South African medical schools were surveyed telephonically. Results: One school was teaching both Traditional African Medicine (TM) and CAM, five were teaching either TM or CAM and another was not teaching any aspect of TCAM. Conclusions: In conclusion, there is a paucity of curricula which incorporate TCAM. Medical schools have not responded to government policies or the contextual realities by incorporating TCAM into the curriculum for their students. South African medical schools need to review their curricula to increase their students' knowledge of TCAM given the demands of the population and the legislative realities
    corecore