389 research outputs found
Artisanal and small scale mining in Mongolia: Statistical overview based on survey data by suom 2012
Atomic-level visualization of the
intercalation of layered materials,
such as metal chalcogenides, is of paramount importance in the development
of high-performance batteries. In situ images of the dynamic intercalation
of Li ions into MoS<sub>2</sub> single-crystal electrodes were acquired
for the first time, under potential control, with the use of a technique
combining laser confocal microscopy with differential interference
microscopy. Intercalation proceeded via a distinct phase separation
of lithiated and delithiated regions. The process started at the atomic
steps of the first layer beneath the selvedge and progressed in a
layer-by-layer fashion. The intercalated regions consisted of Li-ion
channels into which the newly inserted Li ions were pushed atom-by-atom.
Interlayer diffusion of Li ions was not observed. Deintercalation
was also clearly imaged and was found to transpire in a layer-by-layer
mode. The intercalation and deintercalation processes were chemically
reversible and can be repeated many times within a few atomic layers.
Extensive intercalation of Li ions disrupted the atomically flat surface
of MoS<sub>2</sub> because of the formation of small lithiated domains
that peeled off from the surface of the crystal. The current–potential
curves of the intercalation and deintercalation processes were independent
of the scan rate, thereby suggesting that the rate-determining step
was not governed by Butler–Volmer kinetics
Interação genótipo x ambiente em características de crescimento de bovinos da raça Nelore no Mato Grosso do Sul
Efficacy of a low-dose candidate malaria vaccine, R21 in adjuvant Matrix-M, with seasonal administration to children in Burkina Faso: a randomised controlled trial.
BACKGROUND: Stalled progress in controlling Plasmodium falciparum malaria highlights the need for an effective and deployable vaccine. RTS,S/AS01, the most effective malaria vaccine candidate to date, demonstrated 56% efficacy over 12 months in African children. We therefore assessed a new candidate vaccine for safety and efficacy. METHODS: In this double-blind, randomised, controlled, phase 2b trial, the low-dose circumsporozoite protein-based vaccine R21, with two different doses of adjuvant Matrix-M (MM), was given to children aged 5-17 months in Nanoro, Burkina Faso-a highly seasonal malaria transmission setting. Three vaccinations were administered at 4-week intervals before the malaria season, with a fourth dose 1 year later. All vaccines were administered intramuscularly into the thigh. Group 1 received 5 μg R21 plus 25 μg MM, group 2 received 5 μg R21 plus 50 μg MM, and group 3, the control group, received rabies vaccinations. Children were randomly assigned (1:1:1) to groups 1-3. An independent statistician generated a random allocation list, using block randomisation with variable block sizes, which was used to assign participants. Participants, their families, and the local study team were all masked to group allocation. Only the pharmacists preparing the vaccine were unmasked to group allocation. Vaccine safety, immunogenicity, and efficacy were evaluated over 1 year. The primary objective assessed protective efficacy of R21 plus MM (R21/MM) from 14 days after the third vaccination to 6 months. Primary analyses of vaccine efficacy were based on a modified intention-to-treat population, which included all participants who received three vaccinations, allowing for inclusion of participants who received the wrong vaccine at any timepoint. This trial is registered with ClinicalTrials.gov, NCT03896724. FINDINGS: From May 7 to June 13, 2019, 498 children aged 5-17 months were screened, and 48 were excluded. 450 children were enrolled and received at least one vaccination. 150 children were allocated to group 1, 150 children were allocated to group 2, and 150 children were allocated to group 3. The final vaccination of the primary series was administered on Aug 7, 2019. R21/MM had a favourable safety profile and was well tolerated. The majority of adverse events were mild, with the most common event being fever. None of the seven serious adverse events were attributed to the vaccine. At the 6-month primary efficacy analysis, 43 (29%) of 146 participants in group 1, 38 (26%) of 146 participants in group 2, and 105 (71%) of 147 participants in group 3 developed clinical malaria. Vaccine efficacy was 74% (95% CI 63-82) in group 1 and 77% (67-84) in group 2 at 6 months. At 1 year, vaccine efficacy remained high, at 77% (67-84) in group 1. Participants vaccinated with R21/MM showed high titres of malaria-specific anti-Asn-Ala-Asn-Pro (NANP) antibodies 28 days after the third vaccination, which were almost doubled with the higher adjuvant dose. Titres waned but were boosted to levels similar to peak titres after the primary series of vaccinations after a fourth dose administered 1 year later. INTERPRETATION: R21/MM appears safe and very immunogenic in African children, and shows promising high-level efficacy. FUNDING: The European & Developing Countries Clinical Trials Partnership, Wellcome Trust, and National Institute for Health Research Oxford Biomedical Research Centre
Multi-messenger observations of a binary neutron star merger
On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ~1.7 s with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of 40+8-8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 Mo. An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ~40 Mpc) less than 11 hours after the merger by the One- Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ~10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ~9 and ~16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta
Multi-messenger Observations of a Binary Neutron Star Merger
On 2017 August 17 a binary neutron star coalescence candidate (later
designated GW170817) with merger time 12:41:04 UTC was observed through
gravitational waves by the Advanced LIGO and Advanced Virgo detectors.
The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray
burst (GRB 170817A) with a time delay of ∼ 1.7 {{s}} with respect to
the merger time. From the gravitational-wave signal, the source was
initially localized to a sky region of 31 deg2 at a
luminosity distance of {40}-8+8 Mpc and with
component masses consistent with neutron stars. The component masses
were later measured to be in the range 0.86 to 2.26 {M}ȯ
. An extensive observing campaign was launched across the
electromagnetic spectrum leading to the discovery of a bright optical
transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC
4993 (at ∼ 40 {{Mpc}}) less than 11 hours after the merger by the
One-Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The
optical transient was independently detected by multiple teams within an
hour. Subsequent observations targeted the object and its environment.
Early ultraviolet observations revealed a blue transient that faded
within 48 hours. Optical and infrared observations showed a redward
evolution over ∼10 days. Following early non-detections, X-ray and
radio emission were discovered at the transient’s position ∼ 9
and ∼ 16 days, respectively, after the merger. Both the X-ray and
radio emission likely arise from a physical process that is distinct
from the one that generates the UV/optical/near-infrared emission. No
ultra-high-energy gamma-rays and no neutrino candidates consistent with
the source were found in follow-up searches. These observations support
the hypothesis that GW170817 was produced by the merger of two neutron
stars in NGC 4993 followed by a short gamma-ray burst (GRB 170817A) and
a kilonova/macronova powered by the radioactive decay of r-process
nuclei synthesized in the ejecta.</p
Synopsis fungorum hydnaceorum in Svecia nascentium. Cujus partem primam hydna pileata sistentem ... præside mag. Elia Fries ... pro gradu philosophico p. p. auctor Matthias Adolphus Lindblad, Suderm. Neric., stip. Stjernecr. In auditorio Gustaviano minori die XIV Decembris MDCCCLIII. H. P. M. S.
Monographia clitocybarum Sueciae, quam ... præside Elia Fries ... pro gradu philosophico modeste proponit Axelius Peterson Vestm. Dalec. In audit. Gustav. d. VI Maj MDCCCLIV. H. P. M. S., P. II
Novitiarum florae Suecicae mantissa tertia, quam venia ampliss. facult. philosoph. praeside mag. Elia Fries ... pro gradu philosophico p. p. Carolus Thorsten Örtenblad, Vermel. V. D. M. In audit. Gustav. die VIII Junii MDCCCXLII H. a. m. s., III
Monographia lepiotarum Sueciae, quam ... præside Elia Fries ... pro gradu philosophico modeste proponit Magnus Nennes, Smolandus in audit. Gustav. d. [tomrum] Apr. MDCCCLIV. H. P. M. S.
Monographia collybarium Sueciae quam ... præside Elia Fries ... pro gradu philosophico modeste proponit Johannes Victor Björnström Suderm. Neric. In audit. Gustav. d. XVIII Maj MDCCCLIV. H. P. M. S., P. I
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