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Photosubstitutionally active ruthenium complexes show high potential as prodrugs for the photoactivated chemotherapy (PACT) treatment of tumors. One of the problems in PACT is that the localization of the ruthenium compound is hard to trace. Here, a ruthenium PACT prodrug, [Ru(3)(biq)(STF-31)](PF6 )2 (where 3 = 3-(([2,2':6',2″-ter- pyridin]-4'-yloxy)propyl-4-(pyren-1-yl)butanoate) and biq = 2,2'-biquinoline), has been prepared, in which a pyrene tracker is attached via an ester bond. The proximity between the fluorophore and the ruthenium center leads to fluorescence quenching. Upon intracellular hydrolysis of the ester linkage, however, the fluorescence of the pyrene moiety is recovered, thus demonstrating prodrug cellular uptake. Further light irradiation of this molecule liberates by photosubstitution STF-31, a known cytotoxic nicotinamide phosphoribosyltransferase (NAMPT) inhibitor, as well as singlet oxygen via excitation of the free pyrene chromophore. The dark and light cytotoxicity of the prodrug, embedded in liposomes, as well as the appearance of blue emission upon uptake, were evaluated in A375 human skin melanoma cells. The cytotoxicity of the liposome-embedded prodrug was indeed increased by light irradiation. This work realizes an in vitro proof-of-concept of the lock-and-kill principle, which may ultimately be used to design strategies aimed at knowing where and when light irradiation should be realized in vivo.

Heterogeneous thermal properties of Bennu are due primarily to spatial mixing of two boulder types with differing strengths., Thermal inertia and surface roughness are proxies for the physical characteristics of planetary surfaces. Global maps of these two properties distinguish the boulder population on near-Earth asteroid (NEA) (101955) Bennu into two types that differ in strength, and both have lower thermal inertia than expected for boulders and meteorites. Neither has strongly temperature-dependent thermal properties. The weaker boulder type probably would not survive atmospheric entry and thus may not be represented in the meteorite collection. The maps also show a high–thermal inertia band at Bennu’s equator, which might be explained by processes such as compaction or strength sorting during mass movement, but these explanations are not wholly consistent with other data. Our findings imply that other C-complex NEAs likely have boulders similar to those on Bennu rather than finer-particulate regoliths. A tentative correlation between albedo and thermal inertia of C-complex NEAs may be due to relative abundances of boulder types.

A class of hybrid oligosilane–arene materials outperforms the σ- and π-conjugated parent structures., We show that a class of oligosilane–arene σ, π-hybrid materials exhibits distinct and enhanced solid-state electronic properties relative to its parent components. In the single crystal structure, the σ-conjugation axis of one molecule points towards the π-face of a neighboring molecule due to an unusual gauche conformation. This organization is hypothesized to be beneficial for charge transport. We show that solution-deposited crystalline films of the hybrid materials show up to a 100-fold increase in space-charge limited current (SCLC) mobility relative to literature reports of photoinduced hole transport in oligosilane films. The discovery that σ, π-hybrids are more than the sum of their parts offers a design opportunity for new materials.

Many management strategies exist for neuroendocrine liver metastases. These strategies range from surgery to ablation with various interventional radiology procedures, and include both regional and systemic therapy with diverse biological, cytotoxic, or targeted agents. A paucity of biological, molecular, and genomic information and an absence of data from rigorous trials limit the validity of many publications detailing management. This Review represents the views from an international conference, for which 15 expert working groups prepared evidence-based assessments addressing specific questions, and from which an independent jury derived final recommendations. The aim of the conference was to review the existing approaches to neuroendocrine liver metastases, assess the evidence on which management decisions were based, develop internationally acceptable recommendations for clinical practice (when evidence was available), and make recommendations for clinical and research endeavours. This report represents the final clinical statements and proposals for future research. © 2014 Elsevier Ltd.

Although liver transplantation is a widely accepted treatment for hepatocellular carcinoma (HCC), much controversy remains and there is no generally accepted set of guidelines. An international consensus conference was held on Dec 2–4, 2010, in Zurich, Switzerland, with the aim of reviewing current practice regarding liver transplantation in patients with HCC and to develop internationally accepted statements and guidelines. The format of the conference was based on the Danish model. 19 working groups of experts prepared evidence-based reviews according to the Oxford classification, and drafted recommendations answering 19 specific questions. An independent jury of nine members was appointed to review these submissions and make final recommendations, after debates with the experts and audience at the conference. This report presents the final 37 statements and recommendations, covering assessment of candidates for liver transplantation, criteria for listing in cirrhotic and non-cirrhotic patients, role of tumour downstaging, management of patients on the waiting list, role of living donation, and post-transplant management.

The high-yielding synthesis and detailed characterization of two well-defined, linkage isomeric tripodal, tetradentate all-phosphorus ligands 1-3 is described. Coordination to Cu(I) resulted in formation of complexes 4-6, for which the molecular structures indicate overall tridentate coordination to the copper atom in the solid state, with one dangling peripheral phosphine. The solution studies suggest fast exchange between the three phosphine side-arms. For these new Cu(I) complexes, preliminary catalytic activity in the cyclopropanation of styrene with ethyldiazoacetate (EDA) is disclosed. The anticipated well-defined tetradentate coordination in a C(3)-symmetric fashion was achieved with Rh(I) and Ir(I), leading to the overall five-coordinated complexes 7-12. Complex 11 has the norbornadiene (nbd) ligand coordinated in an unprecedented monodentate 2,3-eta(2) mode to Rh. Furthermore, unexpected but very interesting redox-chemistry and reactivity was displayed by the Rh(Cl)-complexes 7 and 8. Oxidation resulted in the formation of stable Rh(II) metalloradicals [7]PF(6) and [8]PF(6) that were characterized by X-ray crystallography, magnetic susceptibility measurements, cyclic voltammetry, and electron paramagnetic resonance (EPR) spectroscopy. Subsequent redox-reactivity of these metalloradicals toward molecular hydrogen is described, resulting in the formation of Rh(III) hydride compounds.

We report the synthesis of a novel type of phosphinourea ligand, its coordination chemistry with rhodium, its use in the asymmetric hydroformylation of styrene, and investigations on the hydroformylation reaction mechanism. Complex studies on the 2:1 complex of phosphinourea to [Rh(acac)(CO)2] showed that a neutral trans-coordinating complex [Rh(HL-κP)(L-κ2O,P)(CO)] was formed. An anionic O,P-chelating ligand has displaced the anionic acac− ligand via an acid−base reaction involving the deprotonation of an acidic urea proton, giving Hacac. A second phosphinourea is coordinated as a neutral monodentate ligand and is linked to the chelating anionic ligand via an intramolecular hydrogen bond. The behavior of these supramolecular complexes in the hydroformylation reaction and the possible cooperative role of the ligands in the catalytic cycle were studied both experimentally and by computational methods. High-pressure NMR spectroscopy revealed that the catalytically active rhodium hydride species further consists of two neutral phosphinourea ligands and is in equilibrium with the neutral species [Rh(HL-κP)(L-κ2O,P)(CO)]. This equilibrium is likely an integrated part of a productive hydroformylation cycle involving a ligand-assisted reductive elimination of the aldehyde. DFT calculations revealed that the ligand-assisted mechanism could well be the preferred lower energetic pathway; however, the orientation of the anionic oxygen donor atom in [Rh(HL-κP)(L-κ2O,P)(CO)] prevented us from finding a direct (nonsolvent assisted) transition state to connect the intermediates. We therefore cannot exclude a mechanism where [Rh(HL-κP)(L-κ2O,P)(CO)] is a dormant species outside the productive hydroformylation cycle, although the intermediate associated with this mechanism is higher in energy. Finally, the synthesis of heteroligated complexes was investigated, consisting of two electronically different phosphinoureas, which sets the stage for combinatorial supramolecular ligand approaches in catalysis. Simply mixing two electronically different phosphinoureas with metal precursor [Rh(acac)(CO)2] resulted in the formation of a heterobidentate ligand. A set of six new phosphinoureas was used to prepare such rhodium complexes in a combinatorial fashion for the asymmetric hydroformylation of styrene, resulting in high conversions and selectivities for the branched product and moderate enantioselectivities.

Crystals of the complex [Ru(C5Me5)(η6-1,3-(Me2NCH2)2C6H4)](BF4) have been examined over the temperature range 150–300 K via X-ray diffraction measurements. This study shows that the Ru complex is a two-phase system in this T-range and the solid–solid transition is reversible. At 150 K, phase II (P21/c, Z′ = 4) is ordered and non-merohedrally twinned, a = 16.4396 (9) A, b = 17.3226 (4) A, c = 32.1874 (11) A, β = 91.375 (2)°. At 295 K, phase I (Pbca, Z′ = 1) is disordered, a = 8.5071 (3) A, b = 17.1567 (3) A, c = 32.8250 (8) A. The relationship between the two phases is obvious because the packing remains similar in the two phases. The greatest structural changes between the two phases are found in the rows of adjacent cations [Ru(C5Me5)(η6-1,3-(Me2NCH2)2C6H4)]+ packed along the a direction. These rows are ordered in phase II but are disordered in phase I. The phase transition is first order. Significant changes in thermal motion for the cations are considered as being the driving force for the occurrence of this phase transition. The X-ray diffraction study showed that the complex [Ru(C5Me5)(η6-1,3-(Me2NCH2)2C6H4)](BF4) is a two-phase system between 150 and 300 K.

Überblick über das Radiometer des Heat Flow and Physical Properties Packages (HP3) der InSight Mission.

Living donor liver transplantation (LDLT), originally used in children with left lateral segment grafts, has been expanded to adults who require larger grafts to support liver function. Most adult LDLT procedures have been performed with right lobe grafts, and this means a significant risk of morbidity for the donors. To minimize the donor risk for adults, there is renewed interest in smaller left lobe grafts. The smaller graft size increases the recipient risk in the form of small-for-size syndrome (SFSS) and essentially transfers the risk from the donor to the recipient. We review the donor and recipient risks of LDLT and pay particular attention to the different types of liver grafts and the use of graft inflow modification to ameliorate the risk of SFSS. Finally, a new metric is proposed for quantifying the recipient benefit in exchange for a specific donor risk. © 2013 AASLD. Copyright © 2013 American Association for the Study of Liver Diseases.

Crystals of the complex [Ru(C5Me5)(g6-1,3- (Me2NCH2)2C6H4)](BF4) have been examined over the temperature range 150–300 K via X-ray diffraction measurements. This study shows that the Ru complex is a twophase system in this T-range and the solid–solid transition is reversible. At 150 K, phase II (P21/c, Z0 = 4) is ordered and non-merohedrally twinned, a = 16.4396 (9) A ° , b = 17.3226 (4) A ° , c = 32.1874 (11) A ° , b = 91.375 (2) . At 295 K, phase I (Pbca, Z0 = 1) is disordered, a = 8.5071 (3) A ° , b = 17.1567 (3) A ° , c = 32.8250 (8) A ° . The relationship between the two phases is obvious because the packing remains similar in the two phases. The greatest structural changes between the two phases are found in the rows of adjacent cations [Ru(C5Me5)(g6-1,3- (Me2NCH2)2C6H4)]? packed along the a direction. These rows are ordered in phase II but are disordered in phase I. The phase transition is first order. Significant changes in thermal motion for the cations are considered as being the driving force for the occurrence of this phase transition.

This note describes the mechanical effects of thermal cycles on a TT half-module, to demonstrate that the detectors can withstand the expected thermal gradients without damage. The stress transferred by the carbon fiber rails and the ceramic to the silicon sensors was investigated, and the deformation that occurred during these tests was measured by strain gauges that were attached to sensors on a test half-module. In addition, heat transfer through the carbon fiber rails was studied. Furthermore, we present a comparison of different materials proposed to build the carbon fiber rails of the modules.

The LHCb Silicon Tracker is a large-surface silicon micro-strip detector that will cover an important part of the LHCb tracking system. Its data will be used in the trigger to select high-p_T daughter particles from B-meson decays, and in the offline analysis to reconstruct trajectories of charged particles in the very forward region of the detector. Readout strips of up to 38 cm in length with strip pitches of approximately 200 micrometer will be employed. For the readout, a custom developed front-end chip and a Gbit digital optical link will be used. The design of detector, silicon sensors and readout link is presented.

Monte Carlo simulations of the expected 1 MeV-neutron equivalent fluence in the Trigger Tracker (TT) station of the LHCb detector have been used to investigate the effect of radiation damage on the performance of the detector. The build-up of leakage currents and the corresponding increase in electronic noise has been investigated, as well as the effect of bulk damage on the full-depletion voltage of the sensors and the risk of thermal runaway due to the power generated due to the leakage currents.

This internal note presents the design and the specifications for the cooling balconies and cooling plate of the LHCb Inner Tracker silicon detector. We describe the material R&D programme, which has been carried out in order to identify appropriate material candidates. Mechanical and thermal measurements on these materials are presented.