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1.
Proc Natl Acad Sci U S A ; 117(43): 26651-26659, 2020 10 27.
Artículo en Inglés | MEDLINE | ID: mdl-33046643

RESUMEN

The 1257 CE eruption of Mount Samalas (Indonesia) is the source of the largest stratospheric injection of volcanic gases in the Common Era. Sulfur dioxide emissions produced sulfate aerosols that cooled Earth's climate with a range of impacts on society. The coemission of halogenated species has also been speculated to have led to wide-scale ozone depletion. Here we present simulations from HadGEM3-ES, a fully coupled Earth system model, with interactive atmospheric chemistry and a microphysical treatment of sulfate aerosol, used to assess the chemical and climate impacts from the injection of sulfur and halogen species into the stratosphere as a result of the Mt. Samalas eruption. While our model simulations support a surface air temperature response to the eruption of the order of -1°C, performing well against multiple reconstructions of surface temperature from tree-ring records, we find little evidence to support significant injections of halogens into the stratosphere. Including modest fractions of the halogen emissions reported from Mt. Samalas leads to significant impacts on the composition of the atmosphere and on surface temperature. As little as 20% of the halogen inventory from Mt. Samalas reaching the stratosphere would result in catastrophic ozone depletion, extending the surface cooling caused by the eruption. However, based on available proxy records of surface temperature changes, our model results support only very minor fractions (1%) of the halogen inventory reaching the stratosphere and suggest that further constraints are needed to fully resolve the issue.

2.
J Endocrinol Invest ; 45(3): 607-615, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34741762

RESUMEN

PURPOSE: To screen for maturity-onset diabetes of the young (MODY) variants in subjects with an early age of onset and positive family history of diabetes mellitus. METHODS: 60 subjects with onset of diabetes between 3 and 30 years of age and parental history (onset < 35 years) of diabetes were recruited after excluding autoimmune, pancreatic and syndromic forms of diabetes. Detailed pedigree chart and clinical data were recorded. MODY genetic testing (MODY 1-13) was performed and variant classification was done adhering to the ACMG guidelines. RESULTS: Baseline characteristics of subjects were as follows: mean age of onset of diabetes 19.9 ± 7 years, mean duration of diabetes 6.3 ± 6.8 years, BMI 23.3 ± 3 kg/m2 and C-peptide 1.56 ± 1.06 nmol/l. Four out of sixty (6.6%) were positive for variants classifiable as pathogenic/likely pathogenic: one patient with HNF4Ac.691C > T, (p.Arg231Trp), two with HNF 1A c.746C > A(p.Ser249Ter) and c.1340C > T(p.Pro447Leu), and one with ABCC8 c.4544C > T (p.Thr1515Met). MODY 1 and MODY 3 variants were documented in the paediatric age group (< 18 years). CONCLUSION: A genetic diagnosis of MODY could be confirmed in only 6.6% (4/60) of patients clinically classifiable as MODY. This is less than that reported in clinically diagnosed MODY subjects of European descent. Newly published population data and more stringent criteria for assessment of pathogenicity and younger age of onset of type 2 diabetes in Indians could have contributed to the lower genetic confirmation rate. Apart from variants in the classical genes (HNF1A, HNF4A), a likely pathogenic variant in a non-classical gene (ABCC8) was noted in this study.


Asunto(s)
Diabetes Mellitus Tipo 2 , Factor Nuclear 1-alfa del Hepatocito/genética , Factor Nuclear 4 del Hepatocito/genética , Receptores de Sulfonilureas/genética , Edad de Inicio , Índice de Masa Corporal , Péptido C/sangre , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/epidemiología , Diabetes Mellitus Tipo 2/genética , Femenino , Pruebas Genéticas/métodos , Variación Genética , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Humanos , India/epidemiología , Masculino , Mutación , Linaje , Adulto Joven
3.
Phys Rev Lett ; 126(7): 072301, 2021 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-33666476

RESUMEN

The yield of charged particles opposite to a Z boson with large transverse momentum (p_{T}) is measured in 260 pb^{-1} of pp and 1.7 nb^{-1} of Pb+Pb collision data at 5.02 TeV per nucleon pair recorded with the ATLAS detector at the Large Hadron Collider. The Z boson tag is used to select hard-scattered partons with specific kinematics, and to observe how their showers are modified as they propagate through the quark-gluon plasma created in Pb+Pb collisions. Compared with pp collisions, charged-particle yields in Pb+Pb collisions show significant modifications as a function of charged-particle p_{T} in a way that depends on event centrality and Z boson p_{T}. The data are compared with a variety of theoretical calculations and provide new information about the medium-induced energy loss of partons in a p_{T} regime difficult to measure through other channels.

4.
Phys Rev Lett ; 126(12): 122301, 2021 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-33834811

RESUMEN

The first measurement of longitudinal decorrelations of harmonic flow amplitudes v_{n} for n=2-4 in Xe+Xe collisions at sqrt[s_{NN}]=5.44 TeV is obtained using 3 µb^{-1} of data with the ATLAS detector at the LHC. The decorrelation signal for v_{3} and v_{4} is found to be nearly independent of collision centrality and transverse momentum (p_{T}) requirements on final-state particles, but for v_{2} a strong centrality and p_{T} dependence is seen. When compared with the results from Pb+Pb collisions at sqrt[s_{NN}]=5.02 TeV, the longitudinal decorrelation signal in midcentral Xe+Xe collisions is found to be larger for v_{2}, but smaller for v_{3}. Current hydrodynamic models reproduce the ratios of the v_{n} measured in Xe+Xe collisions to those in Pb+Pb collisions but fail to describe the magnitudes and trends of the ratios of longitudinal flow decorrelations between Xe+Xe and Pb+Pb. The results on the system-size dependence provide new insights and an important lever arm to separate effects of the longitudinal structure of the initial state from other early and late time effects in heavy-ion collisions.

5.
Phys Rev Lett ; 126(12): 121802, 2021 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-33834820

RESUMEN

Several extensions of the Standard Model predict the production of dark matter particles at the LHC. An uncharted signature of dark matter particles produced in association with VV=W^{±}W^{∓} or ZZ pairs from a decay of a dark Higgs boson s is searched for using 139 fb^{-1} of pp collisions recorded by the ATLAS detector at a center-of-mass energy of 13 TeV. The s→V(qq[over ¯])V(qq[over ¯]) decays are reconstructed with a novel technique aimed at resolving the dense topology from boosted VV pairs using jets in the calorimeter and tracking information. Dark Higgs scenarios with m_{s}>160 GeV are excluded.

6.
Phys Rev Lett ; 127(5): 051802, 2021 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-34397238

RESUMEN

A search for charged leptons with large impact parameters using 139 fb^{-1} of sqrt[s]=13 TeV pp collision data from the ATLAS detector at the LHC is presented, addressing a long-standing gap in coverage of possible new physics signatures. Results are consistent with the background prediction. This search provides unique sensitivity to long-lived scalar supersymmetric lepton partners (sleptons). For lifetimes of 0.1 ns, selectron, smuon, and stau masses up to 720, 680, and 340 GeV, respectively, are excluded at 95% confidence level, drastically improving on the previous best limits from LEP.

7.
West Afr J Med ; 38(4): 321-327, 2021 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-33900713

RESUMEN

BACKGROUND: The ongoing Covid-19 pandemic is now a global health emergency with significant morbidity and mortality among different populations of the world. Healthcare professionals are the people in the front line of situations like this. Their perspectives on the pandemic is critical to their safety and the outcomes in patients they manage. The aim of this study is to assess the knowledge, attitude and practice regarding COVID-19 among clinical healthcare professionals in Bingham University Teaching Hospital (BHUTH) Jos. MATERIALS AND METHODS: A total of 138 clinical health workers from BHUTH completed a questionnaire- based study on the knowledge, attitude and practice on COVID-19 from the April 1st to 30th May 2020. Consecutive sampling method was used for data collection and the distribution of responses was presented as frequencies and percentages. Analysis of Variance (ANOVA) test was used to investigate the level of association among variables at the significance level of p<0.05. RESULTS: The highest mean of correct responses for knowledge were from doctors, pharmacists and nurses with 19.1±2.35, 19.4±1.52 and 18.9±1.73 respectively. The lowest mean was from pharmacist assistant and nurse aids with 17.1±1.81. The difference was statistically significant with Anaysis of Variance (F) of 5.75 and p value of 0.001. The attitude and practice mean were good between the different clinical cadre; however, the difference was not significant. CONCLUSION: There is good knowledge, attitude and practice among the doctors and pharmacists, nurses, nurse assistants and pharmacist assistants. The doctors and pharmacist had better scores. There is the need for regular training and update.


CONTEXTE: La pandémie de Covid-19 en cours est maintenant une urgence sanitaire mondiale avec une morbidité et une mortalité importantes parmi les différentes populations du monde. Les professionnels de la santé sont les personnes en première ligne dans des situations comme celle-ci. Leurs points de vue sur la pandémie sont essentiels à leur sécurité et aux résultats chez les patients qu'ils gèrent. Le but de cette étude est d'évaluer les connaissances, l'attitude et la pratique concernant le COVID-19 parmi les professionnels de la santé cliniques du Bingham University Teaching Hospital (BHUTH) Jos. MATÉRIAUX ET MÉTHODES: Un total de 138 agents de santé cliniques du BHUTH ont terminé une étude basée sur un questionnaire sur les connaissances, l'attitude et la pratique du COVID-19 du 1er avril au 30 mai 2020. La méthode d'échantillonnage consécutif a été utilisée pour la collecte des données et la distribution des réponses a été présentée sous forme de fréquences et de pourcentages. Le test d'analyse de variance (ANOVA) a été utilisé pour étudier le niveau d'association entre les variables au niveau de signification de p <0,05. RÉSULTATS: La moyenne la plus élevée de réponses correctes pour les connaissances était celle des médecins, des pharmaciens et des infirmières avec respectivement 19,1 ± 2,35, 19,4 ± 1,52 et 18,9 ± 1,73. La moyenne la plus faible était celle des assistants pharmaciens et des infirmières auxiliaires avec 17,1 ± 1,81. La différence était statistiquement significative avec F de 5,75 et p de 0,001. L'attitude et la pratique moyenne étaient bonnes entre les différents cadres cliniques; cependant, la différence n'était pas significative. CONCLUSION: Il existe de bonnes connaissances, une bonne attitude et une bonne pratique parmi les médecins et pharmaciens, infirmières, infirmières auxiliaires et pharmaciens assistants. Les médecins et le pharmacien avaient de meilleurs scores. Une formation et une mise à jour régulières sont nécessaires. MOTS CLÉS: COVID-19, connaissances, attitude, pratique, travailleurs de la santé, Nigéria.


Asunto(s)
COVID-19 , Pandemias , Actitud del Personal de Salud , Estudios Transversales , Conocimientos, Actitudes y Práctica en Salud , Personal de Salud , Hospitales de Enseñanza , Humanos , Nigeria , SARS-CoV-2 , Encuestas y Cuestionarios , Universidades
8.
Cardiovasc Diabetol ; 19(1): 7, 2020 01 10.
Artículo en Inglés | MEDLINE | ID: mdl-31924211

RESUMEN

BACKGROUND: Diabetes mellitus type 2 (DM2) is a risk factor for developing heart failure but there is no specific therapy for diabetic heart disease. Sodium glucose transporter 2 inhibitors (SGLT2I) are recently developed diabetic drugs that primarily work on the kidney. Clinical data describing the cardiovascular benefits of SGLT2Is highlight the potential therapeutic benefit of these drugs in the prevention of cardiovascular events and heart failure. However, the underlying mechanism of protection remains unclear. We investigated the effect of Dapagliflozin-SGLT2I, on diabetic cardiomyopathy in a mouse model of DM2. METHODS: Cardiomyopathy was induced in diabetic mice (db/db) by subcutaneous infusion of angiotensin II (ATII) for 30 days using an osmotic pump. Dapagliflozin (1.5 mg/kg/day) was administered concomitantly in drinking water. Male homozygous, 12-14 weeks old WT or db/db mice (n = 4-8/group), were used for the experiments. Isolated cardiomyocytes were exposed to glucose (17.5-33 mM) and treated with Dapagliflozin in vitro. Intracellular calcium transients were measured using a fluorescent indicator indo-1. RESULTS: Angiotensin II infusion induced cardiomyopathy in db/db mice, manifested by cardiac hypertrophy, myocardial fibrosis and inflammation (TNFα, TLR4). Dapagliflozin decreased blood glucose (874 ± 111 to 556 ± 57 mg/dl, p < 0.05). In addition it attenuated fibrosis and inflammation and increased the left ventricular fractional shortening in ATII treated db/db mice. In isolated cardiomyocytes Dapagliflozin decreased intracellular calcium transients, inflammation and ROS production. Finally, voltage-dependent L-type calcium channel (CACNA1C), the sodium-calcium exchanger (NCX) and the sodium-hydrogen exchanger 1 (NHE) membrane transporters expression was reduced following Dapagliflozin treatment. CONCLUSION: Dapagliflozin was cardioprotective in ATII-stressed diabetic mice. It reduced oxygen radicals, as well the activity of membrane channels related to calcium transport. The cardioprotective effect manifested by decreased fibrosis, reduced inflammation and improved systolic function. The clinical implication of our results suggest a novel pharmacologic approach for the treatment of diabetic cardiomyopathy through modulation of ion homeostasis.


Asunto(s)
Compuestos de Bencidrilo/farmacología , Glucemia/efectos de los fármacos , Diabetes Mellitus/tratamiento farmacológico , Cardiomiopatías Diabéticas/prevención & control , Glucósidos/farmacología , Miocitos Cardíacos/efectos de los fármacos , Inhibidores del Cotransportador de Sodio-Glucosa 2/farmacología , Función Ventricular Izquierda/efectos de los fármacos , Angiotensina II , Animales , Biomarcadores/sangre , Glucemia/metabolismo , Canales de Calcio Tipo L/metabolismo , Señalización del Calcio/efectos de los fármacos , Células Cultivadas , Diabetes Mellitus/sangre , Cardiomiopatías Diabéticas/inducido químicamente , Cardiomiopatías Diabéticas/metabolismo , Cardiomiopatías Diabéticas/fisiopatología , Modelos Animales de Enfermedad , Fibrosis , Mediadores de Inflamación/metabolismo , Masculino , Ratones Endogámicos C57BL , Miocitos Cardíacos/metabolismo , Miocitos Cardíacos/patología , Ratas Sprague-Dawley , Intercambiador de Sodio-Calcio/metabolismo , Intercambiador 1 de Sodio-Hidrógeno/metabolismo
9.
Phys Rev Lett ; 125(6): 061802, 2020 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-32845699

RESUMEN

A study of the charge conjugation and parity (CP) properties of the interaction between the Higgs boson and top quarks is presented. Higgs bosons are identified via the diphoton decay channel (H→γγ), and their production in association with a top quark pair (tt[over ¯]H) or single top quark (tH) is studied. The analysis uses 139 fb^{-1} of proton-proton collision data recorded at a center-of-mass energy of sqrt[s]=13 TeV with the ATLAS detector at the Large Hadron Collider. Assuming a CP-even coupling, the tt[over ¯]H process is observed with a significance of 5.2 standard deviations. The measured cross section times H→γγ branching ratio is 1.64_{-0.36}^{+0.38}(stat)_{-0.14}^{+0.17}(sys) fb, and the measured rate for tt[over ¯]H is 1.43_{-0.31}^{+0.33}(stat)_{-0.15}^{+0.21}(sys) times the Standard Model expectation. The tH production process is not observed and an upper limit on its rate of 12 times the Standard Model expectation is set. A CP-mixing angle greater (less) than 43 (-43)° is excluded at 95% confidence level.

10.
Phys Rev Lett ; 125(26): 261801, 2020 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-33449771

RESUMEN

The observation of forward proton scattering in association with lepton pairs (e^{+}e^{-}+p or µ^{+}µ^{-}+p) produced via photon fusion is presented. The scattered proton is detected by the ATLAS Forward Proton spectrometer, while the leptons are reconstructed by the central ATLAS detector. Proton-proton collision data recorded in 2017 at a center-of-mass energy of sqrt[s]=13 TeV are analyzed, corresponding to an integrated luminosity of 14.6 fb^{-1}. A total of 57 (123) candidates in the ee+p (µµ+p) final state are selected, allowing the background-only hypothesis to be rejected with a significance exceeding 5 standard deviations in each channel. Proton-tagging techniques are introduced for cross-section measurements in the fiducial detector acceptance, corresponding to σ_{ee+p}=11.0±2.6(stat)±1.2(syst)±0.3(lumi) and σ_{µµ+p}=7.2±1.6(stat)±0.9(syst)±0.2(lumi) fb in the dielectron and dimuon channel, respectively.

11.
Phys Rev Lett ; 125(25): 251802, 2020 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-33416363

RESUMEN

This Letter presents a search for the production of new heavy resonances decaying into a Higgs boson and a photon using proton-proton collision data at sqrt[s]=13 TeV collected by the ATLAS detector at the LHC. The data correspond to an integrated luminosity of 139 fb^{-1}. The analysis is performed by reconstructing hadronically decaying Higgs boson (H→bb[over ¯]) candidates as single large-radius jets. A novel algorithm using information about the jet constituents in the center-of-mass frame of the jet is implemented to identify the two b quarks in the single jet. No significant excess of events is observed above the expected background. Upper limits are set on the production cross-section times branching fraction for narrow spin-1 resonances decaying into a Higgs boson and a photon in the resonance mass range from 0.7 to 4 TeV, cross-section times branching fractions are excluded between 11.6 fb and 0.11 fb at a 95% confidence level.

12.
Phys Rev Lett ; 125(22): 221802, 2020 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-33315463

RESUMEN

A search for Higgs boson decays into a Z boson and a light resonance in two-lepton plus jet events is performed, using a pp collision dataset with an integrated luminosity of 139 fb^{-1} collected at sqrt[s]=13 TeV by the ATLAS experiment at the CERN LHC. The resonance considered is a light boson with a mass below 4 GeV from a possible extended scalar sector or a charmonium state. Multivariate discriminants are used for the event selection and for evaluating the mass of the light resonance. No excess of events above the expected background is found. Observed (expected) 95% confidence-level upper limits are set on the Higgs boson production cross section times branching fraction to a Z boson and the signal resonance, with values in the range 17-340 pb (16_{-5}^{+6}-320_{-90}^{+130} pb) for the different light spin-0 boson mass and branching fraction hypotheses, and with values of 110 and 100 pb (100_{-30}^{+40} and 100_{-30}^{+40} pb) for the η_{c} and J/ψ hypotheses, respectively.

13.
Phys Rev Lett ; 125(13): 131801, 2020 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-33034503

RESUMEN

This Letter describes a search for narrowly resonant new physics using a machine-learning anomaly detection procedure that does not rely on signal simulations for developing the analysis selection. Weakly supervised learning is used to train classifiers directly on data to enhance potential signals. The targeted topology is dijet events and the features used for machine learning are the masses of the two jets. The resulting analysis is essentially a three-dimensional search A→BC, for m_{A}∼O(TeV), m_{B},m_{C}∼O(100 GeV) and B, C are reconstructed as large-radius jets, without paying a penalty associated with a large trials factor in the scan of the masses of the two jets. The full run 2 sqrt[s]=13 TeV pp collision dataset of 139 fb^{-1} recorded by the ATLAS detector at the Large Hadron Collider is used for the search. There is no significant evidence of a localized excess in the dijet invariant mass spectrum between 1.8 and 8.2 TeV. Cross-section limits for narrow-width A, B, and C particles vary with m_{A}, m_{B}, and m_{C}. For example, when m_{A}=3 TeV and m_{B}≳200 GeV, a production cross section between 1 and 5 fb is excluded at 95% confidence level, depending on m_{C}. For certain masses, these limits are up to 10 times more sensitive than those obtained by the inclusive dijet search. These results are complementary to the dedicated searches for the case that B and C are standard model bosons.

14.
Phys Rev Lett ; 125(5): 051801, 2020 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-32794886

RESUMEN

A search for heavy neutral Higgs bosons is performed using the LHC Run 2 data, corresponding to an integrated luminosity of 139 fb^{-1} of proton-proton collisions at sqrt[s]=13 TeV recorded with the ATLAS detector. The search for heavy resonances is performed over the mass range 0.2-2.5 TeV for the τ^{+}τ^{-} decay with at least one τ-lepton decaying into final states with hadrons. The data are in good agreement with the background prediction of the standard model. In the M_{h}^{125} scenario of the minimal supersymmetric standard model, values of tanß>8 and tanß>21 are excluded at the 95% confidence level for neutral Higgs boson masses of 1.0 and 1.5 TeV, respectively, where tanß is the ratio of the vacuum expectation values of the two Higgs doublets.

15.
Phys Rev Lett ; 124(8): 082301, 2020 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-32167369

RESUMEN

The elliptic flow of muons from the decay of charm and bottom hadrons is measured in pp collisions at sqrt[s]=13 TeV using a data sample with an integrated luminosity of 150 pb^{-1} recorded by the ATLAS detector at the LHC. The muons from heavy-flavor decay are separated from light-hadron decay muons using momentum imbalance between the tracking and muon spectrometers. The heavy-flavor decay muons are further separated into those from charm decay and those from bottom decay using the distance-of-closest-approach to the collision vertex. The measurement is performed for muons in the transverse momentum range 4-7 GeV and pseudorapidity range |η|<2.4. A significant nonzero elliptic anisotropy coefficient v_{2} is observed for muons from charm decays, while the v_{2} value for muons from bottom decays is consistent with zero within uncertainties.

16.
Phys Rev Lett ; 124(22): 222002, 2020 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-32567910

RESUMEN

The prevalence of hadronic jets at the LHC requires that a deep understanding of jet formation and structure is achieved in order to reach the highest levels of experimental and theoretical precision. There have been many measurements of jet substructure at the LHC and previous colliders, but the targeted observables mix physical effects from various origins. Based on a recent proposal to factorize physical effects, this Letter presents a double-differential cross-section measurement of the Lund jet plane using 139 fb^{-1} of sqrt[s]=13 TeV proton-proton collision data collected with the ATLAS detector using jets with transverse momentum above 675 GeV. The measurement uses charged particles to achieve a fine angular resolution and is corrected for acceptance and detector effects. Several parton shower Monte Carlo models are compared with the data. No single model is found to be in agreement with the measured data across the entire plane.

17.
Phys Rev Lett ; 124(3): 031802, 2020 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-32031842

RESUMEN

A search for magnetic monopoles and high-electric-charge objects is presented using 34.4 fb^{-1} of 13 TeV pp collision data collected by the ATLAS detector at the LHC during 2015 and 2016. The considered signature is based upon high ionization in the transition radiation tracker of the inner detector associated with a pencil-shape energy deposit in the electromagnetic calorimeter. The data were collected by a dedicated trigger based on the tracker high-threshold hit capability. The results are interpreted in models of Drell-Yan pair production of stable particles with two spin hypotheses (0 and 1/2) and masses ranging from 200 to 4000 GeV. The search improves by approximately a factor of 5 the constraints on the direct production of magnetic monopoles carrying one or two Dirac magnetic charges and stable objects with electric charge in the range 20≤|z|≤60 and extends the charge range to 60<|z|≤100.

18.
Geophys Res Lett ; 47(20): e2020GL090326, 2020 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-33173249

RESUMEN

We present an assessment of the impacts on atmospheric composition and radiative forcing of short-lived pollutants following a worldwide decrease in anthropogenic activity and emissions comparable to what has occurred in response to the COVID-19 pandemic, using the global composition-climate model United Kingdom Chemistry and Aerosols Model (UKCA). Emission changes reduce tropospheric hydroxyl radical and ozone burdens, increasing methane lifetime. Reduced SO2 emissions and oxidizing capacity lead to a decrease in sulfate aerosol and increase in aerosol size, with accompanying reductions to cloud droplet concentration. However, large reductions in black carbon emissions increase aerosol albedo. Overall, the changes in ozone and aerosol direct effects (neglecting aerosol-cloud interactions which were statistically insignificant but whose response warrants future investigation) yield a radiative forcing of -33 to -78 mWm-2. Upon cessation of emission reductions, the short-lived climate forcers rapidly return to pre-COVID levels; meaning, these changes are unlikely to have lasting impacts on climate assuming emissions return to pre-intervention levels.

19.
Prenat Diagn ; 40(3): 351-357, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31713898

RESUMEN

OBJECTIVE: The objective of this study is to determine factors associated with poor outcomes and the need for surgical treatment in neonates with meconium peritonitis (MP). METHODS: We evaluated the association between prenatal ultrasound features, maternal characteristics, and the likelihood of surgery, mortality, and serious morbidity in 49 neonates with a prenatal diagnosis of MP, who were born in Guangzhou Women and Children's Medical Center between January 2011 and December 2016. RESULTS: Thirty of 49 neonates (61.2%) required surgical treatment, and 17 (34.7%) had a poor outcome. Independent predictors of need for surgical treatment were polyhydramnios, maternal intrahepatic cholestasis of pregnancy (associated with lower risk), and persistence of peritoneal fluid. The model correctly predicted 70.0% of the neonates who required surgery (at a 10% false-positive rate; area under the curve [AUC]: 0.86 [95% CI, 0.75-0.97]). For poor outcomes, independent predictors were low gestational age at birth, persistence of peritoneal fluid, and polyhydramnios. For the latter, the model only achieved a detection rate of 52.9% (10% false-positive rate, AUC: 0.82 [95% CI, 0.70-0.94]). CONCLUSIONS: A combination of prenatal ultrasound features and maternal characteristics correctly predicted 70.0% the need for neonatal surgery. Prediction of poor outcome-based prenatal ultrasound features and gestational age did not perform well.


Asunto(s)
Meconio , Peritonitis/diagnóstico , Peritonitis/cirugía , Ultrasonografía Prenatal , Adulto , Cesárea , China , Colestasis Intrahepática/complicaciones , Femenino , Edad Gestacional , Humanos , Recién Nacido , Masculino , Peritonitis/mortalidad , Embarazo , Complicaciones del Embarazo , Estudios Retrospectivos , Resultado del Tratamiento
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