Extracting the Pair Distribution Function of Liquids and Liquid-Vapor Surfaces by Grazing Incidence X-ray Diffraction Mode

We show that the structure factor $S(q)$ of water can be obtained from X-ray synchrotron experiments at grazing angle of incidence (in reflection mode) by using a liquid surface diffractometer. The corrections used to obtain $S(q)$ self-consistently are described. Applying these corrections to scans at different incident beam angles (above the critical angle) collapses the measured intensities into a single master curve, without fitting parameters, which within a scale factor yields $S(q)$. Performing the measurements below the critical angle for total reflectivity yields the structure factor of the top most layers of the water/vapor interface. Our results indicate water restructuring at the vapor/water interface. We also introduce a new approach to extract $g(r)$, the pair distribution function (PDF), by expressing the PDF as a linear sum of Error functions whose parameters are refined by applying a non-linear least square fit method. This approach enables a straightforward determination of the inherent uncertainties in the PDF. Implications of our results to previously measured and theoretical predictions of the PDF are also discussed

Beneficial and harmful effects of sacubitril/valsartan in patients with heart failure:A systematic review of randomised clinical trials with meta-analysis and trial sequential analysis

Current guidelines recommend angiotensin receptor blocker neprilysin inhibitors (ARNI) (sacubitril/valsartan) as a replacement for angiotensin-converting-enzymeinhibitor (ACE-I) in heart failure with reduced ejection fraction (HFrEF) who remain symptomatic despite optimal medical therapy. The effects of ARNIs have not previously been assessed in a systematic review. We searched for relevant trials until October 2019 in CENTRAL, MEDLINE, Embase, LILACS, BIOSIS, CNKI, VIP, WanFang and CBM. Our primary outcomes were all-cause mortality and serious adverse events. We systematically assessed the risks of random errors and systematic errors. PROSPERO registration: CRD42019129336. 48 trials randomising 19 086 participants were included. The ARNI assessed in all trials was sacubitril/valsartan. ACE-I or ARB were used as control interventions. Trials randomising HFrEF participants (27 trials) and heart failure with preserved ejection fraction (HFpEF) participants (four trials) were analysed separately. In HFrEF participants, meta-analyses and Trial Sequential Analyses showed evidence of a beneficial effect of sacubitril/valsartan when assessing all-cause mortality (risk ratio (RR), 0.86; 95% CI, 0.79 to 0.94) and serious adverse events (RR, 0.89; 95% CI, 0.86 to 0.93); and the results did not differ between the guideline recommended target population and HFrEF participants in general. We found no evidence of an effect of sacubitril/valsartan in HFpEF participants. Sacubitril/valsartan compared with either ACE-I or ARB seems to have a beneficial effect in patients with HFrEF. Our results indicate that sacubitril/valsartan might be beneficial in a wider population of patients with heart failure than the guideline recommended target population. Sacubitril/valsartan does not seem to show evidence of a difference compared with valsartan in patients with HFpEF. </p

The culture variable vis-à-vis anti-bribery law: a grey area in transnational corporate criminal liability

Cross-border transactions are generating corresponding globalisation of law enforcement efforts. Culture has significantly influenced the legal analysis of anti-bribery law. With the increase of transnational bribery, benefits from globalisation will be undermined unless an effective legal regime can mitigate the harm of bribery. It is perceived that corruption in China is more prevalent than in the West given its embedded place in Chinese culture. It is further alleged that Chinese multinational companies (MNCs) are taking advantage of an unlevel playing field, as they are not subject to stringently-enforced anti-bribery laws. This hypothesis creates a myriad of anti-bribery problems in terms of legislation and enforcement, which particularly manifest in China’s perceived cultural toleration of bribery. Cultural assumptions undermine the global anti-bribery regime and compromise potential collaborative anti-bribery efforts across jurisdictions in a rapidly globalizing world. The Chinese culture does not necessarily impede China’s criminalisation of paying bribes to foreign officials. It is argued that the cultural role should not be overestimated, otherwise the hazard of the ethnocentric engagement with the Chinese culture would affect the ability of foreign MNCs to integrate their global compliance programmes. Multinationals can only mitigate their exposure to criminal liability globally, provided that they comply robustly with anti-bribery laws of both home and host jurisdictions

Study of hadronic event-shape variables in multijet final states in pp collisions at √s=7 TeV

Peer reviewe

QCD and strongly coupled gauge theories : challenges and perspectives

We highlight the progress, current status, and open challenges of QCD-driven physics, in theory and in experiment. We discuss how the strong interaction is intimately connected to a broad sweep of physical problems, in settings ranging from astrophysics and cosmology to strongly coupled, complex systems in particle and condensed-matter physics, as well as to searches for physics beyond the Standard Model. We also discuss how success in describing the strong interaction impacts other fields, and, in turn, how such subjects can impact studies of the strong interaction. In the course of the work we offer a perspective on the many research streams which flow into and out of QCD, as well as a vision for future developments.Peer reviewe

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

Constraints on parton distribution functions and extraction of the strong coupling constant from the inclusive jet cross section in pp collisions at √s=7 TeV

Peer reviewe

Hotspots and key periods of Greenland climate change during the past six decades

We investigated air temperature and pressure gradients and their trends for the period 1996–2014 in Greenland and compared these to other periods since 1958. Both latitudinal temperature and pressure gradients were strongest during winter. An overall temperature increase up to 0.15 °C year(−1) was observed for 1996–2014. The strongest warming happened during February at the West coast (up to 0.6 °C year(−1)), weaker but consistent and significant warming occurred during summer months (up to 0.3 °C year(−1)) both in West and East Greenland. Pressure trends on a monthly basis were mainly negative, but largely statistically non-significant. Compared with other time windows in the past six decades, the period 1996–2014 yielded an above-average warming trend. Northeast Greenland and the area around Zackenberg follow the general pattern but are on the lower boundary of observed significant trends in Greenland. We conclude that temperature-driven ecosystem changes as observed in Zackenberg may well be exceeded in other areas of Greenland