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We have derived values of the Ultraviolet Index (UVI) at solar noon using the Tropospheric Ultraviolet Model (TUV) driven by ozone, temperature and aerosol fields from climate simulations of the first phase of the Chemistry-Climate Model Initiative (CCMI-1). Since clouds remain one of the largest uncertainties in climate projections, we simulated only the clear-sky UVI. We compared the modelled UVI climatologies against present-day climatological values of UVI derived from both satellite data (the OMI-Aura OMUVBd product) and ground-based measurements (from the NDACC network). Depending on the region, relative differences between the UVI obtained from CCMI/TUV calculations and the ground-based measurements ranged between −5.9% and 10.6%. We then calculated the UVI evolution throughout the 21st century for the four Representative Concentration Pathways (RCPs 2.6, 4.5, 6.0 and 8.5). Compared to 1960s values, we found an average increase in the UVI in 2100 (of 2–4%) in the tropical belt (30°N-30°S). For the mid-latitudes, we observed a 1.8 to 3.4 % increase in the Southern Hemisphere for RCP 2.6, 4.5 and 6.0, and found a 2.3% decrease in RCP 8.5. Higher increases in UVI are projected in the Northern Hemisphere except for RCP 8.5. At high latitudes, ozone recovery is well identified and induces a complete return of mean UVI levels to 1960 values for RCP 8.5 in the Southern Hemisphere. In the Northern Hemisphere, UVI levels in 2100 are higher by 0.5 to 5.5% for RCP 2.6, 4.5 and 6.0 and they are lower by 7.9% for RCP 8.5. We analysed the impacts of greenhouse gases (GHGs) and ozone-depleting substances (ODSs) on UVI from 1960 by comparing CCMI sensitivity simulations (1960–2100) with fixed GHGs or ODSs at their respective 1960 levels. As expected with ODS fixed at their 1960 levels, there is no large decrease in ozone levels and consequently no sudden increase in UVI levels. With fixed GHG, we observed a delayed return of ozone to 1960 values, with a corresponding pattern of change observed on UVI, and looking at the UVI difference between 2090s values and 1960s values, we found an 8 % increase in the tropical belt during the summer of each hemisphere. Finally we show that, while in the Southern Hemisphere the UVI is mainly driven by total ozone column, in the Northern Hemisphere both total ozone column and aerosol optical depth drive UVI levels, with aerosol optical depth having twice as much influence on the UVI as total ozone column does.

Africa is rapidly urbanising and urban food systems are being transformed. Some have argued that this transformation is driven by a supermarket revolution akin to that in North America, Europe and ...

Background: The first antiretroviral drug (Truvada) to be used as a pre-exposure prophylaxis (PrEP) in preventing HIV transmission is about to be approved. Behavioral studies suggest that a portion of users may share anti-retroviral drugs with sex partners, family, or friends. Pill sharing will decrease PrEP efficacy and adherence level, and potentially create an environment favorable for the development of drug resistance. We aim to evaluate the potential impact of pill sharing on the PrEP effectiveness and on the rates of drug-resistance development in heterosexual populations. Methods: A transmission dynamic model was used to assess the population-level impact of oral PrEP. The fractions of new HIV infections prevented (CPF), drug resistance prevalence and the proportion of new infections in which drug-resistant HIV is transmitted (TDR) are evaluated over fixed time periods. The influence of different factors on CPF and TDR is studied through simulations, using epidemic parameters representative of the countries in Sub-Saharan Africa. Results: Without pill sharing, a 70% efficacious PrEP used consistently by 60% of uninfected individuals prevents 52.8% (95% CI 49.4%-56.4%) of all new HIV infections over ten years with drug-resistant HIV transmitted in 2.2% of the new infections. Absolute CPF may vary by 9% if up to 20% of the users share PrEP while the level of TDR and total resistance prevalence may increase by up to 6-fold due to pill sharing in some intervention scenarios. Conclusion: Pill sharing may increase the PrEP coverage level achieved in the population but it also affects the PrEP efficacy for the users who do not follow the prescribed schedule. More importantly, it creates a pool of untracked users who remain unreached by the effort to avoid sub-optimal PrEP usage by infected people. This increases substantially the potential risk of drug resistance in the population

We thank CERN for the very successful operation of the LHC, as well as the support staff from our institutions without whom ATLAS could not be operated efficiently. We acknowledge the support of ANPCyT, Argentina; YerPhI, Armenia; ARC, Australia; BMWFW and FWF, Austria; ANAS, Azerbaijan; SSTC, Belarus; CNPq and FAPESP, Brazil; NSERC, NRC and CFI, Canada; CERN; CONICYT, Chile; CAS, MOST and NSFC, China; COLCIENCIAS, Colombia; MSMT CR, MPO CR and VSC CR, Czech Republic; DNRF and DNSRC, Denmark; IN2P3-CNRS, CEA-DRF/IRFU, France; SRNSFG, Georgia; BMBF, HGF, and MPG, Germany; GSRT, Greece; RGC, Hong Kong SAR, China; ISF and Benoziyo Center, Israel; INFN, Italy; MEXT and JSPS, Japan; CNRST, Morocco; NWO, Netherlands; RCN, Norway; MNiSW and NCN, Poland; FCT, Portugal; MNE/IFA, Romania; MES of Russia and NRC KI, Russian Federation; JINR; MESTD, Serbia; MSSR, Slovakia; ARRS and MIZS, Slovenia; DST/NRF, South Africa; MINECO, Spain; SRC and Wallenberg Foundation, Sweden; SERI, SNSF and Cantons of Bern and Geneva, Switzerland; MOST, Taiwan; TAEK, Turkey; STFC, United Kingdom; DOE and NSF, United States of America. In addition, individual groups and members have received support from BCKDF, CANARIE, CRC and Compute Canada, Canada; COST, ERC, ERDF, Horizon 2020, and Marie Sklodowska-Curie Actions, European Union; Investissements d' Avenir Labex and Idex, ANR, France; DFG and AvH Foundation, Germany; Herakleitos, Thales and Aristeia programmes co-financed by EU-ESF and the Greek NSRF, Greece; BSF-NSF and GIF, Israel; CERCA Programme Generalitat de Catalunya, Spain; The Royal Society and Leverhulme Trust, United Kingdom. The crucial computing support from all WLCG partners is acknowledged gratefully, in particular from CERN, the ATLAS Tier-1 facilities at TRIUMF (Canada), NDGF(Denmark, Norway, Sweden), CC-IN2P3 (France), KIT/GridKA (Germany), INFN-CNAF (Italy), NL-T1 (Netherlands), PIC (Spain), ASGC (Taiwan), RAL (UK) and BNL (USA), the Tier-2 facilities worldwide and large non-WLCG resource providers. Major contributors of comp Measurements of the azimuthal anisotropy in lead–lead collisions at sNN−−−√ = 5.02 TeV are presented using a data sample corresponding to 0.49 nb−1 integrated luminosity collected by the ATLAS experiment at the LHC in 2015. The recorded minimum-bias sample is enhanced by triggers for “ultra-central” collisions, providing an opportunity to perform detailed study of flow harmonics in the regime where the initial state is dominated by fluctuations. The anisotropy of the charged-particle azimuthal angle distributions is characterized by the Fourier coefficients, v2–v7, which are measured using the two-particle correlation, scalar-product and event-plane methods. The goal of the paper is to provide measurements of the differential as well as integrated flow harmonics vn over wide ranges of the transverse momentum, 0.5

Abstract Background Severe aortic stenosis (AS) can lead to left heart dysfunction, pulmonary hypertension (PH), and eventually right heart failure. Clinical phenotypes therefore appear heterogeneous, depending on disease progression and comorbidities. Purpose This study therefore sought to improve diagnostic and prognostic resolution in patients undergoing transcatheter aortic valve replacement (TAVR) for severe AS by developing a man-machine interaction-based phenotyping approach. Methods Unsupervised agglomerative clustering was applied to preprocedural data from echocardiography and right heart catheterization from 366 consecutively enrolled patients undergoing TAVR for severe AS. Echocardiographic follow-up data, obtained on day 147±75.1 after TAVR, were available from 247 patients (67.5%). Results Cluster analysis revealed four distinct phenotypes, reflecting various extents of disease severity, and hence differing in mortality. Patients from cluster 1 presented with preserved left ventricular ejection fraction (LVEF; 57.2±6.4%) and with normal mean pulmonary artery pressure (mPAP) levels (21.2±6.5 mmHg). In contrast, patients in cluster 2 suffered from postcapillary PH (mPAP: 34.2±7.8 mmHg). Left heart failure (LVEF: 42.4±15.7%), severe PH (mPAP: 46.9±8.5 mmHg), and right heart dysfunction (tricuspid annular plane systolic excursion [TAPSE]: 16.1±4.57 mm) characterized patients in cluster 3. Patients from cluster 4 showed mild postcapillary PH (mPAP: 27.5±9.2 mmHg), yet dilatation of all heart chambers, biventricular dysfunction (LVEF: 47.3±12.2%, TAPSE: 16.8±4.5 mm), and a high prevalence of both mitral and tricuspid regurgitation (12.5% and 14.8%, respectively). Correction of severe AS by TAVR significantly reduced the proportion of patients suffering from concurrent severe mitral regurgitation (from 9.29% to 3.64%, p-value: 0.0015). Moreover, pulmonary artery pressures were ameliorated (estimated systolic pulmonary artery pressure: from 47.2±15.8 mmHg to 43.3±15.1 mmHg, p-value: 0.0079). However, right heart dysfunction as well as the proportion of patients with severe tricuspid regurgitation remained unchanged. Clusters 3 and 4 with persistent right heart dysfunction ultimately displayed 2-year survival rates of 69.2% (95% CI: 56.6–84.7%) and 74.6% (95% CI: 65.9–84.4%), which were significantly lower compared to clusters 1 and 2 with little or no persistent cardiopulmonary impairment (88.3% [95% CI: 83.3–93.5%] and 85.5% [95% CI: 77.1–94.8%]). Conclusion This phenotyping approach preprocedurally identifies patients with severe AS, who will not recover from extra-aortic valve cardiac damage following TAVR and whose survival is therefore significantly reduced. Importantly, not the degree of PH at initial presentation, but the irreversibility of right heart dysfunction determines prognosis. Funding Acknowledgement Type of funding sources: None.

We calculate the impact of quantum gravity-motivated ultraviolet cutoffs on inflationary predictions for the cosmic microwave background spectrum. We model the ultraviolet cutoffs fully covariantly to avoid possible artifacts of covariance breaking. Imposing these covariant cutoffs results in the production of small, characteristically $k-$dependent oscillations in the spectrum. The size of the effect scales linearly with the ratio of the Planck to Hubble lengths during inflation. Consequently, the relative size of the effect could be as large as one part in $10^5$; i.e., eventual observability may not be ruled out. Comment: 5 pages, 3 figures - v2: minor corrections, added references -v3: harmonize with published version