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YYS acknowledges support from the Funds for Women Graduates (GA-00558). FG and CJB acknowledge support from EPSRC through Grants EP/M029077/1 and EP/S027270/1. RS acknowledges financial support from the Scottish Funding Council through SRD-Grant HR07003. On-surface synthesis with designer precursor molecules is considered an effective method for preparing graphene nanoribbons (GNRs) of well-defined widths and with tunable electronic properties. Recent reports have shown that the band gap of ribbons doped with heteroatoms (such as boron, nitrogen, and sulfur) remains unchanged in magnitude in most cases. Nevertheless, theory predicts that a tunable band gap may be engineered by hydrogenation, but experimental evidence for this is so far lacking. Herein, surface-confined hydrogenation studies of 7-armchair graphene nanoribbons (7-AGNRs) grown on Au(111) surfaces, in an ultrahigh vacuum environment, are reported. GNRs are first prepared, then hydrogenated by exposure to activated hydrogen atoms. High resolution electron energy loss spectroscopy (HREELS) and scanning tunneling microscopy (STM) images reveal a self-limited hydrogenation process. By means of a combination of bond-resolved scanning tunneling microscopy (BRSTM) imaging and tip-induced site-specific dehydrogenation, the hydrogenation mechanism is studied in detail, and density-functional theory (DFT) calculation methods are used to complement the experimental findings. In all cases, the results demonstrate the successful modification of the electronic properties of the GNR/Au(111) system by edge and basal-plane hydrogenation, and a mechanism for the hydrogenation process is proposed. Publisher PDF

M.T. gratefully acknowledges financial support from Lubrizol Limited and thanks the Engineering and Physical Sciences Research Council (EPSRC) grant EP/L015307/1 for the Molecular Analytical Science Centre for Doctoral Training (MAS-CDT). C.G. acknowledges the use of the Euler cluster at ETH Zurich for the DFT calculations. F.G. acknowledges funding from the EPSRC (grant EP/S027270/1). The interaction of benzotriazole (BTAH) with Cu(100) has been studied as a function of BTAH exposure in a joint experimental and theoretical effort. Scanning tunnelling microscopy (STM), X-ray photoelectron spectroscopy (XPS), high resolution electron energy loss spectroscopy (HREELS) and density functional theory (DFT) calculations have been combined to elucidate the structural and chemical characteristics of this system. BTAH is found to deprotonate upon adsorption on the copper surface and to adopt an orientation that depends on the molecular coverage. Benzotriazolate (BTA) species initially lie with their planes parallel to the substrate but, at a higher molecular coverage, a transition occurs to an upright adsorption geometry. Upon increasing the BTAH exposure, different phases of vertically aligned BTAs are observed with increasing molecular densities until a final, self-limiting monolayer is developed. Both theory and experiment agree in identifying CuBTA and Cu(BTA)2 metal-organic complexes as the fundamental building blocks of this monolayer. This work shows several similarities with the results of previous studies on the interaction of benzotriazole with other low Miller index copper surfaces, thereby ideally completing and concluding them. The overall emerging picture constitutes an important starting point for understanding the mechanism for protection of copper from corrosion. Publisher PDF

M.T. gratefully acknowledges financial support from Lubrizol Limited and, together with J.E., thank the Engineering and Physical Sciences Research Council (EPSRC) grant EP/L015307/1 for the Molecular Analytical Science Centre for Doctoral Training (MAS-CDT). C.G acknowledges the Euler cluster managed by the HPC team at ETH Zurich for computational resources and is grateful for computational support from the UK national high performance computing service, ARCHER, for which access was obtained via the UKCP consortium and funded by EPSRC grant EP/P022561/1. Benzotriazole (BTAH) has been used for several industrial applications, but most commonly as a corrosion inhibitor for copper, since the 1950s. However, the mechanism of its interaction with copper surfaces at the atomistic scale is still a matter of debate. Here, the adsorption of BTAH onto a clean Cu(110) surface has been investigated by a combination of scanning tunnelling microscopy, X-ray photoelectron spectroscopy, high resolution electron energy loss spectroscopy and density functional theory calculations. Different supramolecular structures have been observed depending on molecular coverage and annealing. In the low coverage regime, flat lying deprotonated species are formed which give way to benzotriazolate molecules in an upright configuration by increasing the BTAH exposure. The ensuing monolayer is self-limiting but, upon annealing above 150 °C, transforms into a highly ordered nano-ridge structure resulting from a significant in-plane and out-of-plane reconstruction of the surface. All structures are characterised by a strong molecule-substrate interaction and the high coverage phases are dominated by the formation of metal-organic complexes between copper adatoms and benzotriazolate species. These findings shed light on the nature and strength of the interaction occurring between BTAH and copper which lies at the basis of the effectiveness of this prototypical corrosion inhibitor. Postprint

OBJECTIVE: The aim of this study was to evaluate the survival benefit of sirolimus in patients undergoing liver transplantation (LT) for hepatocellular carcinoma (HCC) (exploratory analysis of the SiLVER-trial). SUMMARY AND BACKGROUND DATA: Patients receiving LT) for HCC are at a high risk for tumor recurrence. Calcineurin inhibitors have shown evidence to promote cancer growth, whereas mammalian target of rapamycin (mTOR) inhibitors like sirolimus have anticancer effects. In the SiLVER-trial (Clinicaltrials.gov: NCT00355862), the effect of sirolimus on the recurrence of HCC after LT was investigated in a prospective randomized trial. Although the primary endpoint of improved disease-free survival (DFS) with sirolimus was not met, outcomes were improved for patients in the sirolimus-treatment arm in the first 3 to 5 years. To learn more about the key variables, a multivariate analysis was performed on the SiLVER-trial data. PATIENTS AND METHODS: Data from 508 patients of the intention-to-treat analysis were included in exploratory univariate and multivariate models for overall survival (OS), DFS and a competing risk analysis for HCC recurrence. RESULTS: Sirolimus use for ≥3 months after LT for HCC independently reduced the hazard for death in the multivariate analysis [hazard ratio (HR): 0.7 (95% confidence interval, CI: 0.52-0.96, P = 0.02). Most strikingly, patients with an alpha-fetoprotein (AFP) ≥10 ng/mL and having used sirolimus for ≥3 months, benefited most with regard to OS, DFS, and HCC-recurrence (HR: 0.49-0.59, P = 0.0079-0.0245). CONCLUSIONS: mTOR-inhibitor treatment with sirolimus for ≥3 months improves outcomes in LT for HCC, especially in patients with AFP-evidence of higher tumor activity, advocating particularly for mTOR inhibitor use in this subgroup of patients. CLINICAL TRIAL REGISTRATION: EudraCT: 2005-005362-36 CLINICALTRIALS.GOV:: NCT00355862. ispartof: ANNALS OF SURGERY vol:272 issue:5 pages:855-862 ispartof: location:United States status: published

Intestinal and multivisceral transplantation represents an important treatment option for patients with intestinal failure. Early attempts were hindered by technical and immunological complications. However, significant developments in immunosuppressive therapy have led to marked improvements in outcomes in recent years. The main indications for intestinal transplantation are life-threatening complications or unacceptable quality of life on total parenteral nutrition (TPN), or following evisceration for extensive intra-abdominal tumours. In suitable patients, in the absence of significant liver disease, an isolated intestinal graft is appropriate. A combined liver and intestinal transplant is indicated in patients with significant liver disease, almost always as a result of long-term TPN. Pathology affecting the foregut may require more extensive grafts including the stomach, duodenum and pancreas. Multivisceral transplantation is technically demanding. The transplant recipient has frequently undergone multiple previous laparotomies and may present with multiple stomata, fistulae, collections, distortion of intra-abdominal anatomy and significant contraction of the abdominal cavity. The most important early complications are acute rejection and sepsis, which frequently occur together. In the long-term, chronic rejection and malignancy are the leading causes of graft loss and mortality and immunosuppression related renal impairment a major source of morbidity. It is hoped that ongoing improvements in intestinal and multivisceral transplantation may eventually justify its use as a primary alternative to long-term TPN.

Background The benefits of cold pulsatile machine perfusion (MP) for the storage and transportation of kidneys donated after circulatory death are disputed. We conducted a UK-based multicenter, randomized controlled trial to compare outcomes of kidneys stored with MP versus static cold storage (CS). Methods Fifty-one pairs of kidneys donated after circulatory death were randomly allocated to receive static CS or cold pulsatile MP. The primary endpoint, delayed graft function, was analyzed by "intention-to-treat" evaluation. Results There was no difference in the incidence of delayed graft function between CS and MP (32/51 (62.8%) and 30/51 (58.8%) P = 0.69, respectively), although the trial stopped early due to difficulty with recruitment. There was no difference in the incidence of acute rejection, or in graft or patient survival between the CS and MP groups. Median estimated glomerular filtration rate at 3 months following transplantation was significantly lower in the CS group compared with MP (CS 34 mL/min IQR 26-44 vs MP 45 mL/min IQR 36-60, P = 0.006), although there was no significant difference in estimated glomerular filtration rate between CS and MP at 12 months posttransplant. Conclusions This study is underpowered, which limits definitive conclusions about the use of MP, as an alternative to static CS. It did not demonstrate that the use of MP reduces the incidence of delayed graft function in donation after circulatory death kidney transplantation.

Funding: Scottish Funding Council (through EaStCHEM and SRD-Grant HR07003) and from EPSRC (PhD studentship for JAGT, EP/M506631/1). We present a new method for calculating the frequencies and intensities of the vibrational modes of adsorbates on surfaces. Our method is based on density functional perturbation theory (DFPT) and provides accurate estimates of the vibrational intensities even when the vibrations are strongly anharmonic. Furthermore, it does so at a negligible additional computation cost compared to conventional DFPT calculation. We illustrate our method by calculating the vibrational spectra of three example systems — ethylidyne on Rh(111), benzene on Rh(111) coadsorbed with CO, and terephthalic acid (TPA) on Cu(100) — and comparing them to experimental measurements performed using High-Resolution Electron Energy Loss Spectroscopy (HREELS). We find excellent agreement between our predictions and the experimentally measured frequencies and intensities in all three cases. Postprint Postprint

FG has received funding from the European Community’s Seventh Framework Programme (FP7/2007-2013) under grant agreement nº 312284 for part of the research leading to these results (NEXAFS, photoelectron spectroscopy). The Engineering and Physical Sciences Research Council (EPSRC) is acknowledged for the funding of CRL’s PhD studentship (EP/M506631/1). Prof. Christopher J. Baddeley (University of St Andrews) and Dr. Silvano Lizzit (SuperESCA beam line, Elettra) are thanked for fruitful discussions. The reactivity of benzotriazole with copper on a gold surface has been studied by a combination of surface sensitive methods with support from DFT (density functional theory) calculations. For some time benzotriazole has been known to enhance the corrosion resistance of copper at the monolayer level, although the exact mechanism is still a matter of discussion and disagreement in the literature. A single crystal Au(111) surface allows to evaluate the interaction of weakly physisorbed, intact benzotriazole molecules with copper atoms dosed to sub-monolayer amounts. These interactions have been characterised, in the temperature range ca. 300 – 650 K, by scanning tunnelling microscopy, high resolution electron energy loss spectroscopy and synchrotron-based X-ray photoemission spectroscopy and near-edged X-ray absorption fine structure studies. Supporting DFT calculations considered the stability of isolated, gas-phase, benzotriazole/Cu species and their corresponding spectroscopic signature at the N K absorption edge. In agreement with previous investigations, benzotriazole physisorbs on a clean Au(111) surface at room temperature forming a hydrogen-bonded network of flat-lying BTAH molecules, relatively weakly bonded to the underlying gold surface. However, in the presence of co-adsorbed copper atoms, proton removal from the molecules leads to species better described as BTA- interacting directly with Cu atoms. In these situations the molecules adopt a more upright orientation and Cu(BTA)2 and -[Cu(BTA)]n- species are formed, depending on temperature and coverage of the adsorbed species. These species are stable to relatively high temperatures, 550 – 600 K. Postprint