28 research outputs found
Lives saved with vaccination for 10 pathogens across 112 countries in a pre-COVID-19 world.
BackgroundVaccination is one of the most effective public health interventions. We investigate the impact of vaccination activities for Haemophilus influenzae type b, hepatitis B, human papillomavirus, Japanese encephalitis, measles, Neisseria meningitidis serogroup A, rotavirus, rubella, Streptococcus pneumoniae, and yellow fever over the years 2000-2030 across 112 countries.MethodsTwenty-one mathematical models estimated disease burden using standardised demographic and immunisation data. Impact was attributed to the year of vaccination through vaccine-activity-stratified impact ratios.ResultsWe estimate 97 (95%CrI[80, 120]) million deaths would be averted due to vaccination activities over 2000-2030, with 50 (95%CrI[41, 62]) million deaths averted by activities between 2000 and 2019. For children under-5 born between 2000 and 2030, we estimate 52 (95%CrI[41, 69]) million more deaths would occur over their lifetimes without vaccination against these diseases.ConclusionsThis study represents the largest assessment of vaccine impact before COVID-19-related disruptions and provides motivation for sustaining and improving global vaccination coverage in the future.FundingVIMC is jointly funded by Gavi, the Vaccine Alliance, and the Bill and Melinda Gates Foundation (BMGF) (BMGF grant number: OPP1157270 / INV-009125). Funding from Gavi is channelled via VIMC to the Consortium's modelling groups (VIMC-funded institutions represented in this paper: Imperial College London, London School of Hygiene and Tropical Medicine, Oxford University Clinical Research Unit, Public Health England, Johns Hopkins University, The Pennsylvania State University, Center for Disease Analysis Foundation, Kaiser Permanente Washington, University of Cambridge, University of Notre Dame, Harvard University, Conservatoire National des Arts et Métiers, Emory University, National University of Singapore). Funding from BMGF was used for salaries of the Consortium secretariat (authors represented here: TBH, MJ, XL, SE-L, JT, KW, NMF, KAMG); and channelled via VIMC for travel and subsistence costs of all Consortium members (all authors). We also acknowledge funding from the UK Medical Research Council and Department for International Development, which supported aspects of VIMC's work (MRC grant number: MR/R015600/1).JHH acknowledges funding from National Science Foundation Graduate Research Fellowship; Richard and Peggy Notebaert Premier Fellowship from the University of Notre Dame. BAL acknowledges funding from NIH/NIGMS (grant number R01 GM124280) and NIH/NIAID (grant number R01 AI112970). The Lives Saved Tool (LiST) receives funding support from the Bill and Melinda Gates Foundation.This paper was compiled by all coauthors, including two coauthors from Gavi. Other funders had no role in study design, data collection, data analysis, data interpretation, or writing of the report. All authors had full access to all the data in the study and had final responsibility for the decision to submit for publication
Correction to: Cluster identification, selection, and description in Cluster randomized crossover trials: the PREP-IT trials
An amendment to this paper has been published and can be accessed via the original article
Impact of Film Thickness and Temperature on Ultrafast Excess Charge Dynamics in Ionic Liquid Films
Correction to “Femtosecond Trapping of Free Electrons in Ultrathin Films of NaCl on Ag(100)”
Impact of Film Thickness and Temperature on Ultrafast Excess Charge Dynamics in Ionic Liquid Films
Ultrafast
response of the room temperature ionic liquid (RTIL)
1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide ([Bmpyr][NTf<sub>2</sub>]) to a photoinjected electron is investigated in few-monolayer
films using time- and angle-resolved two-photon photoemission spectroscopy.
A delocalized precursor state and a localized solvated state were
resolved at early times, but after 200 fs only a single solvated state
was observed. The dynamics of film response to this solvated state
were shown to depend significantly on film temperature and thickness.
Population lifetime measurements demonstrated that the RTIL film can
significantly affect the coupling between solvated state and metal
substrate, as the solvated state’s average lifetime increased
from 90 ± 20 fs in 1 ML films to 195 ± 83 ps in 3 ML films.
Additionally, a temperature dependence of the time-dependent binding
energy shift of the solvated state after ca. 500 fs was attributed
to a phase change occurring between the two temperature regimes that
were investigated. Results from xenon overlayer experiments suggest
that the solvation process occurs near the surface of the RTIL film.
Finally, film degradation was found to be present, suggesting that
the observed solvation response could involve a radical species
Metal/Phthalocyanine Hybrid Interface States on Ag(111)
A phthalocyanine/Ag(111) interface state is observed for the first time using time- and angle-resolved two-photon photoemission. For monolayer films of metal-free (H<sub>2</sub>Pc) and iron phthalocyanine (FePc) on Ag(111), the state exists 0.23 ± 0.03 and 0.31 ± 0.03 eV above the Fermi level, respectively. Angle-resolved spectra show the state to be highly dispersive with an effective mass of 0.50 ± 0.15 m<sub>e</sub> for H<sub>2</sub>Pc and 0.67 ± 0.14 m<sub>e</sub> for FePc. Density functional theory calculations on the H<sub>2</sub>Pc/Ag(111) surface allow us to characterize this state as being a hybrid state resulting from the interaction between the unoccupied molecular states of the phthalocyanine ligand and the Shockley surface state present on the bare Ag(111) surface. This work, when taken together with the extensive literature on the 3,4,9,10-perylene tetracarboxylic dianhydride/Ag interface state, provides compelling evidence that the hybridization of metal surface states with molecular electronic states is a general phenomenon
Picosecond TRIR Studies of M<sub>3</sub>(CO)<sub>12</sub> (M = Fe, Os) Clusters in Solution
The
picosecond photochemical dynamics of two group 8 transition
metal carbonyl clusters, Fe<sub>3</sub>(CO)<sub>12</sub> and Os<sub>3</sub>(CO)<sub>12</sub>, have been studied using ultrafast time-resolved
infrared spectroscopy. In both the iron and osmium clusters, no trimetallic
photoproducts containing bridging carbonyls appear to be formed upon
267 or 400 nm photolysis of nonbridged parent molecules. This directly
contrasts with the results of observations made previously for the
Ru<sub>3</sub>(CO)<sub>12</sub> congener, in which photolysis of the
nonbridged parent complex led exclusively to the formation of trimetallic
photoproducts containing bridging carbonyls. In the present study,
the only complex for which photolysis led to bridging carbonyl photoproducts
was the bridged, <i>C</i><sub>2<i>v</i></sub> isomer
of Fe<sub>3</sub>(CO)<sub>12</sub>. For the iron cluster, excitation
leads primarily to a mixture of transient metal–metal bond
cleavage photoproducts with lifetimes on the picosecond time scale,
along with Fe(CO)<sub>4</sub> and Fe<sub>2</sub>(CO)<sub>8</sub> photoproducts
arising from fragmentation of the cluster. For the osmium cluster,
similar metal–metal cleavage transients are observed to recover
on the picosecond time scale, and a longer-lived carbonyl loss complex
is also observed. Taken in conjunction with the existing literature
on the photochemistry of the ruthenium congener, the results of this
study highlight the nuanced nature of group 8 transition metal cluster
photochemistry
Femtosecond Trapping of Free Electrons in Ultrathin Films of NaCl on Ag(100)
We
report the excited-state electron dynamics for ultrathin films
of NaCl on Ag(100). The first three image potential states (IPSs)
were initially observed following excitation. The electrons in the
spatially delocalized <i>n</i> = 1 IPS decayed on the ultrafast
time scale into multiple spatially localized states lower in energy.
The localized electronic states are proposed to correspond to electrons
trapped at defects in the NaCl islands. Coverage and temperature dependence
of the localized states support the assignment to surface trap states
existing at the NaCl/vacuum interface. These results highlight the
importance of electron trapping in ultrathin insulating layers