Global Carbon Budget: Ocean carbon sink.

CO2 emissions from human activities, the main contributor to global climate change, are set to rise again in 2014 reaching 40 billion tonnes CO2 The natural carbon ‘sinks’ on land and in the ocean absorb on average 55% of the total CO2 emissions, thus slowing the rate of global climate change Increasing CO2 in the oceans is causing ocean acidificatio

Singularity in the electron-core potential as a gateway to accurate multielectron ionization spectra in strongly driven atoms

We demonstrate a general three-dimensional semiclassical model as a powerful technique for the study of correlated multielectron escape in atoms driven by infrared laser pulses at intensities where electron-electron correlation prevails. We do so in the context of triple ionization of strongly driven Ne. Our model fully accounts for the singularity in the Coulomb potentials of a recolliding electron with the core and a bound electron with the core as well as for the interaction of a recolliding with a bound electron. To avoid artificial autoionization, our model employs effective potentials to treat the interaction between bound electrons. We show the accuracy of our model by obtaining triple ionization distributions of the sum of the final electron momenta which we find to be in very good agreement with experiments. Also, we explain the main features of these momenta distributions in terms of the prevalent pathways of correlated three-electron escape in Ne. We also show that the different ionization pathways prevailing in three-electron escape in strongly driven Ne versus Ar give rise to different momenta distributions in these two atoms. Our general model may be used to identify novel ultrafast phenomena and to motivate further experiments in strong field science

Reaching peak emissions

Rapid growth in global CO2 emissions from fossil fuels and industry ceased in the past two years, despite continued economic growth. Decreased coal use in China was largely responsible, coupled with slower global growth in petroleum and faster growth in renewables

Comment on “The global tree restoration potential”

This is the author accepted manuscript. The final version is available from American Association for the Advancement of Science via the DOI in this record.Bastin et al. (Reports, 5 July 2019, p. 76) claim that global tree restoration is the most effective climate change solution to date, with a reported carbon storage potential of 205 gigatonnes of carbon. However, this estimate and its implications for climate mitigation are inconsistent with the dynamics of the global carbon cycle and its response to anthropogenic carbon dioxide emissions.European UnionEuropean Commissio

Signatures of magnetic-field effects in nonsequential double ionization manifesting as backscattering for molecules versus forward scattering for atoms

For two-electron diatomic molecules, we investigate magnetic field effects in nonsequential double ionization where recollisions prevail. We do so by formulating a three-dimensional semiclassical model that fully accounts for the Coulomb singularities and for magnetic field effects during time propagation. Using this model, we identify a prominent signature of nondipole effects. Namely, we demonstrate that the recolliding electron backscatters along the direction of light propagation. Hence, this electron escapes opposite to the direction of change in momentum due to the magnetic field. This is in striking contrast to strongly driven atoms where the recolliding electron forward scatters along the direction of light propagation. We attribute these distinct signatures to the different gate that the magnetic field creates jointly with a soft recollision in molecules compared to a hard recollision in atoms. These two different gates give rise, shortly before recollision, to different momenta and positions of the recolliding electron along the direction of light propagation. As a result, we show that the Coulomb forces from the nuclei act to backscatter the recolliding electron in molecules and forward scatter it in atoms along the direction of light propagation

Gestational diabetes in women living with HIV in the UK and Ireland: insights from population-based surveillance data

INTRODUCTION: The prevalence of gestational diabetes (GD) is increasing globally. While universal risk factors for GD are reasonably well understood, questions remain regarding risks for women living with HIV (WLWH). We aimed to describe GD prevalence, evaluate associated maternal risk factors and assess specific birth outcomes in WLWH in the UK and Ireland. METHODS: We analysed all pregnancies (≥24 weeks' gestation) in women diagnosed with HIV before delivery, reported to the UK-based Integrated Screening Outcomes Surveillance Service between 2010 and 2020. Every report of GD was considered as a case. A multivariable logistic regression model, adjusted for women with more than one pregnancy fitted with generalized estimating equations (GEE) assessed the effect of independent risk factors. RESULTS: There were 10,553 pregnancies in 7916 women, of which 460 (4.72%) pregnancies had reported GD. Overall, the median maternal age was 33 years (Q1:29-Q3:37), and 73% of pregnancies were in Black African women. WLWH with GD (WLWH-GD) were older (61% vs. 41% aged ≥35 years, p 350 cells/μl (GEE-aOR: 0.73, 95% CI: 0.50-0.96). CONCLUSIONS: GD prevalence increased over time among WLWH but was not significantly different from the general population. Maternal age, ethnicity and CD4 count were risk factors based on available data. Stillbirth and preterm delivery were more common in WLWH-GD than other WLWH over the study period. Further studies are required to build upon these results

Gestational diabetes in women living with HIV in the UK and Ireland: insights from population-based surveillance data

INTRODUCTION: The prevalence of gestational diabetes (GD) is increasing globally. While universal risk factors for GD are reasonably well understood, questions remain regarding risks for women living with HIV (WLWH). We aimed to describe GD prevalence, evaluate associated maternal risk factors and assess specific birth outcomes in WLWH in the UK and Ireland. METHODS: We analysed all pregnancies (≥24 weeks' gestation) in women diagnosed with HIV before delivery, reported to the UK-based Integrated Screening Outcomes Surveillance Service between 2010 and 2020. Every report of GD was considered as a case. A multivariable logistic regression model, adjusted for women with more than one pregnancy fitted with generalized estimating equations (GEE) assessed the effect of independent risk factors. RESULTS: There were 10,553 pregnancies in 7916 women, of which 460 (4.72%) pregnancies had reported GD. Overall, the median maternal age was 33 years (Q1:29-Q3:37), and 73% of pregnancies were in Black African women. WLWH with GD (WLWH-GD) were older (61% vs. 41% aged ≥35 years, p 350 cells/μl (GEE-aOR: 0.73, 95% CI: 0.50-0.96). CONCLUSIONS: GD prevalence increased over time among WLWH but was not significantly different from the general population. Maternal age, ethnicity and CD4 count were risk factors based on available data. Stillbirth and preterm delivery were more common in WLWH-GD than other WLWH over the study period. Further studies are required to build upon these results

Temporary reduction in daily global CO2 emissions during the COVID-19 forced confinement

Government policies during the COVID-19 pandemic have drastically altered patterns of energy demand around the world. Many international borders were closed and populations were confined to their homes, which reduced transport and changed consumption patterns. Here we compile government policies and activity data to estimate the decrease in CO2 emissions during forced confinements. Daily global CO2 emissions decreased by –17% (–11 to –25% for ±1σ) by early April 2020 compared with the mean 2019 levels, just under half from changes in surface transport. At their peak, emissions in individual countries decreased by –26% on average. The impact on 2020 annual emissions depends on the duration of the confinement, with a low estimate of –4% (–2 to –7%) if prepandemic conditions return by mid-June, and a high estimate of –7% (–3 to –13%) if some restrictions remain worldwide until the end of 2020. Government actions and economic incentives postcrisis will likely influence the global CO2 emissions path for decades

Duration of ruptured membranes and mother-to-child HIV transmission: a prospective population-based surveillance study

OBJECTIVE: To investigate the association between duration of rupture of membranes (ROM) and mother-to-child HIV transmission (MTCT) rates in the era of combination antiretroviral therapy (cART). DESIGN: The National Study of HIV in Pregnancy and Childhood (NSHPC) undertakes comprehensive population-based surveillance of HIV in pregnant women and children. SETTING: UK and Ireland. POPULATION: A cohort of 2398 singleton pregnancies delivered vaginally, or by emergency caesarean section, in women on cART in pregnancy during the period 2007-2012 with information on duration of ROM; HIV infection status was available for 1898 infants. METHODS: Descriptive analysis of NSHPC data. MAIN OUTCOME MEASURES: Rates of MTCT. RESULTS: In 2116 pregnancies delivered at term, the median duration of ROM was 3 hours 30 minutes (interquartile range, IQR 1-8 hours). The overall MTCT rate for women delivering at term with duration of ROM ≥4 hours was 0.64% compared with 0.34% for ROM <4 hours, with no significant difference between the groups (OR 1.90, 95% CI 0.45-7.97). In women delivering at term with a viral load of <50 copies/ml, there was no evidence of a difference in MTCT rates with duration of ROM ≥4 hours, compared with <4 hours (0.14% for ≥4 hours versus 0.12% for <4 hour; OR 1.14, 95% CI 0.07-18.27). Among infants born preterm with infection status available, there were no transmissions in 163 deliveries where the maternal viral load was <50 copies/ml. CONCLUSIONS: No association was found between duration of ROM and MTCT in women taking cART. TWEETABLE ABSTRACT: Rupture of membranes of more than 4 hours is not associated with MTCT of HIV in women on effective ART delivering at term