The Automatic Train Operation of a metro line is not so difficult to implement: almost no junction or crossing between lines, rolling stock homogeneity, double track operation, relatively low speed, very simple station track layout, mostly rubber-mounted, and specific site continuously fenced with no level crossing. Tunnels and platform screen doors complete the picture to prevent almost totally the presence of an obstacle or a person on the tracks. But how can Automatic Train Operation for a metro line be transposed into a long distance train line or further into a country wide network? This paper reminds firstly the different Grades of Automation. Then, it shows Automatic Train Operation used in conjunction with the Communication Based Traffic Control that drives Automatic Train Operation of a metro line. Some information about Automatic or Automatic-like Train Operation Systems are also given in a traditional rail network context and what it is possible to do right now. Finally, the paper presents some alternatives to face challenges met in a Semi-Automatic Train Operation context and in an Unattended Train Operation context. To resume, the actual use of the Packet 44 of the European Train Control System is sufficient for Semi-Automatic Train Operations. Nevertheless, a speed information should complete the actual definition of timings points to obtain a more efficient Automatic Train Operation system. Unattended Train Operation is thinkable in the future, namely with the help of video/infrared cameras in front of the train. Images processing and remote control will then deal with risks and degraded situations.

Dealing with a congested railway area becomes an important topic in railway operation management.Significant efforts are made to develop a Driver Advisory System (DAS) in connection with the trackside Train Management System (TMS).Many advantages are expected from smoothing train dynamic speed profiles: timetable resilience, significant reduction of both the energy consumption and the wear and tear and, finally, positive impacts on the comfort for passengers.Today, on the one hand, only a few Centrally Guided Train Operation Systems (CGTO) are already in operation on European major railways.On the other hand, the European Train Control System (ETCS) spreads rapidly.Such combination offers a great opportunity to promote a European standard CGTO system using the ETCS-DMI opportunities.The present paper describes many options using either the "Monitoring" area, or the "Supplementary Driving Info" area, or the "Planning" area, or the "Speed Info" area; or a combination of them on the ETCS Diver Machine Interface (DMI).Some of them give only advices or guidance but some of them indicate operational temporary speed reductions (O_TSR) that are mandatory.Historical research, current experiments, and dispatching concepts in bottlenecks areas militate in favour of the compulsory character of temporary speed limits due to congestion.Therefore, the last option presented here should be more examined more in depth.

Pacing trains is an important part of railway operations management.It helps to improve the resilience of a timetable to perturbation and reduces significantly both the energy consumption and the wear-and-tear, while increasing the comfort for passengers.Today, only a few Driver Advisory Systems (DAS) with such abilities are already in operation on European major railways.This situation provides great opportunity to promote a unique but flexible system, which can be implemented and used around Europe.The paper describes a concept for a Versatile Driver Advisory System (VDAS).The on-board part of this system is not only fully compatible with a European Driver Advisory System (EDAS) coming from Traffic Management Systems (TMS) but also with other DAS (NEDAS).To ensure flexibility and versatility, EDAS can be implemented in different ways.The use of the standard railway radio GSM-R and the opportunity to send speed advices on the ETCS-DMI are milestones on the development of ETML, the management layer of ERTMS.VDAS facilitates the improvement of the operational resilience to perturbation as well as sparing energy, offers synergy opportunities with the ETCS On-board system and, finally, VDAS is based on EDAS which may become a European standard.

The conclusion is inevitable: Increasing stabilization of an anionic transition state with increasing π-acidity of the catalyst is observed; thus, anion-π interactions can contribute to catalysis.

This paper assesses solution alternatives for railway driver advice systems. To do so a two stage assessment procedure is adopted. First, a wide range of existing systems is identified, using a basis of scientific literature and input from a field survey. Next, the reviewed systems are evaluated using a set of criteria, like: distribution of intelligence, processing unit integration, driver interface, positioning system and communication requirements. The above provides a clear structure for the assessment of DAS, aiming to identify which systems should be investigated in more detail as potential components of real-world deployment. The results highlight major differences in the way that intelligence and processing capabilities are distributed between the control center and the train. They also highlight different approaches to the integration of driver interface, train positioning systems and communication technologies that facilitate the exchange of information between the track and the train. The decision to embark on one of the various approaches depends not only on algorithmic issues but also on human factors considerations, the limits of technology and the costs of upgrading it. Practical aspects such as technical and spatial characteristics of the driver’s cabin, context and format of the advisory information are also of importance.

Die zunehmende Stabilisierung eines anionischen Übergangszustands mit steigender π-Acidität eines neuen Katalysators belegt beispiellos auf experimentelle Weise, dass Anion-π-Wechselwirkungen zur Katalyse beitragen können. In ihrer Zuschrift auf S. 10124 ff. zeigen S. Matile et al. ferner anhand von theoretischen Simulationen zur Anion-π-Katalyse, dass die negative Ladung über die π-acide Oberfläche des Naphthalindiimid-Katalysators gleitet.

This work illustrates how minor structural perturbations produced by methylation of 4'-(dodecyloxy)-4-cyanobiphenyl leads to enthalpy-entropy compensation for their melting processes, a trend which can be analyzed within the frame of a simple intermolecular cohesive model. The transformation of the melting thermodynamic parameters collected at variable temperatures into cohesive free-energy densities expressed at a common reference temperature results in a novel linear correlation, from which melting temperatures can be simply predicted from molecular volumes.

The expansion of the number of intermolecular interactions available to create molecular functional systems is of paramount importance. Quite recently, we have identified synthetic transport systems as attractive tools to elaborate on interactions that are otherwise difficult to detect. Realized examples include anion–p interactions, halogen bonds, and anion–macrodipole interactions. Intriguing results with transport promised attractive applications to catalysis, because evidence for anion binding in the ground state implied that anionic transition states could be similarly stabilized. Anion–p interactions were particularly interesting for this purpose because wonderful examples exist for catalysis with complementary cation–p interactions, reaching from carbocation stabilization in terpenoid and steroid cyclization to surprisingly rare and recent use in organocatalysis. Anion–p interactions, however, have essentially not been used in catalysis. This is understandable, because experimental evidence for their functional relevance appeared only recently, and discussions concerning their nature and significance continue. The poor development of the field presumably originates from the limited occurrence, availability, and diversity of the required p-acids, that is aromatic rings with strong enough electron-withdrawing substituents to invert their usually negative quadrupole moments into positive ones. The Kemp elimination is an established tool to develop conceptually innovative catalysts. Useless with regard to applications in organocatalysis, this reaction has served well to elaborate on theoretically designed enzymes, catalytic antibodies, promiscuous proteins, synthetic polymers, macrocyclic model systems, vesicles, micelles, and non-specific medium effects. The key step is the deprotonation of a carbon in the benzisoxazole substrate S by a general base (Figure 1). The reaction then proceeds with a single anionic transition state to afford the nitrophenolate either as intermediate or product, depending on conditions. There is general agreement that catalysis in its most general sense occurs by transition-state stabilization. The anionic nature of the transition state thus qualified the Kemp elimination as a valid tool to identify contributions from anion–p interactions to catalysis. Herein, we report that p-acidic naphthalenediimides (NDIs) with a covalently attached carboxylate base can catalyze the Kemp elimination and, most importantly, that the stabilization of the anionic transition state of this transformation increases with increasing p-acidity of the new catalysts. The key to “anion–p catalysis” was to take the p-acidic surface of an NDI (variable and strong), and to attach a carboxylate base on one side and a solubilizing tail on the other side (Figure 2). With this design, p-stacking between substrate and catalyst should hold throughout the transformation. The onset of anion–p interactions between the compound in transformation and the catalyst C (Figure 1), however, should coincide exactly with the key step, that is the injection of a negative charge from the proximal carboxylate into the substrate. The translocation of this negative charge over five atoms (from the carboxylate oxygen to the Figure 1. Catalysis of the Kemp elimination with anion–p interactions. A carboxylate is placed as general base near the p-acidic surface of catalyst C to 1) couple deprotonation with the onset of anion–p interactions for transition-state (TS) stabilization, and 2) protonate the phenolate in the reactive intermediate (RI) to avoid product inhibition. blue = electron deficient, red = electron rich, S = substrate, P= product, CS = catalyst–substrate complex, CP = catalyst–product complex.

As long as a train does not conflict with others trains, the energy consumption for traction can be minimized according to its times of departure, arrival, and passing through fixed points. However, when a conflict of itineraries is foreseen, pacing trains becomes a priority task to minimize delays on one hand but also to try to minimize energy consumption, wear and discomfort on the other hand. This paper presents two simple ways to pace trains thanks to a simple piece of information sent to drivers. The first one is to send information to drivers by phone about the next foreseen conflict concerning their train. The second one uses the track-side signalling system to inform the driver about the clearance of some track sections ahead of the train. Both ways let experimented drivers a large freedom to manage tight situations in a satisfying manner.

Lipophilic methyl-substituted cyanobiphenyls can be considered as molecular salmon that jump out of the condensed phase, but are limited by an increase in size of their rigid core. The concept of cohesive free-energy densities applied to melting processes correlates the molecular volumes of the constituents with the macroscopic enthalpic and entropic changes that accompany the phase transitions of the bulk materials. For more details see the Full Paper by E. Terazzi, C. Piguet et al. on page 8447 ff. Lipophilic methyl-substituted cyanobiphenyls can be considered as molecular salmon that jump out of the condensed phase, but are limited by an increase in size of their rigid core. The concept of cohesive free-energy densities applied to melting processes correlates the molecular volumes of the constituents with the macroscopic enthalpic and entropic changes that accompany the phase transitions of the bulk materials. For more details see the Full Paper by E. Terazzi, C. Piguet et al. on page 8447 ff. Drug Protection Skin photosensitivity remains one of the main limitations in photodynamic therapy. In this Concept article by B. Therrien on page 8378 ff., a strategy is described to overcome this limitation, in which the photosensitizer is hidden inside the hydrophobic cavity of a water-soluble organometallic cage. The metallacage not only protects the photosensitizer from light, but also facilitates its delivery to cancer cells.1 Nanoparticle Functionalization A photochemical thiol-yne reaction was used to functionalize iron oxide nanoparticles with various thiols. This metal-free click reaction is easy to use, versatile, chemoselective, and applicable to biomolecules. In their Communication on page 8388 ff., E. Guénin et al. show that this technique can be used to perform chemoselective double functionalization of nanoparticle surfaces.1 Heterobimetallic Cuprates Several bimetallic silyl halido cuprates of the general formula [CuX{Si(3,5-Me2pz)3Mo(CO)3}]− are reported in the Full Paper by F. Breher et al. on page 8436 ff. The electronic and structural properties of the complexes were probed in detail by X-ray diffraction analysis, IR-induced multiphoton dissociation studies, cyclic voltammetry, gas-phase photoelectron spectroscopy, UV/Vis and fluorescence spectroscopy. The picture shows a van der Waals plot of the silyl chloro cuprate in the background and the different characterization techniques applied in the foreground.1

Recently, our group reported on the development of an unprecedented process in copper-catalyzed Asymmetric Allylic Alkylation. This method allowed for the quantitative transformation of a racemic substrate into an enantioenriched product. While a high level of asymmetric induction (up to 99% ee) was observed, the mechanistic understanding of the reaction remained fuzzy. In the present article, a thorough mechanistic analysis, based on computational investigations, led to the identification of the reaction pathway. Notably, it uncovered that both enantiomers of the starting material converged independently to the same product via two different mechanistic routes. This specific feature established this process as a rare example of Direct Enantioconvergent Transformation. Finally, the modelling results prompted a valuable improvement of the reaction, relying on the use of a more accessible range of substrates.

« Pas aussi vite que possible mais aussi rapidement que nécessaire. » Dans ce slogan promouvant le grand projet d’horaire cadencé coordonné des chemins de fer suisses « Rail 2000 », la notion de correspondance est sous-jacente. Le chemin a toutefois été long avant que les ruptures de charge ne soient plus vues comme un handicap majeur mais au contraire comme une opportunité de pouvoir aller de n’importe où à n’importe où en transport en commun à n’importe quelle heure de la journée. Le projet de développement du réseau ferré suisse de 1850 préconise un réseau ferré complémentaire au réseau de transport lacustre. C’est l’ère des ruptures de charge intermodales. En 1900 encore, le réseau à écartement normal est composé de nombreuses compagnies alors qu’il a moins de 3 000 km de lignes, ce qui génère bon nombre de ruptures de charge intramodales. À la sortie de la Deuxième Guerre mondiale, le réseau suisse à voie normale est presque totalement électrifié. Les progrès techniques permettent aux trains d’être plus lourds et d’atteindre les limites de vitesse des lignes. Le développement de l’aviation commerciale permet à la Régie fédérale d’amener directement ses trains nationaux dans les aéroports intercontinentaux dès 1980, augmentant non seulement le confort mais aussi la vitesse commerciale des voyageurs. Alors que le TGV Paris-Lyon commence à rouler, un référendum national met en échec le développement de la grande vitesse ferroviaire en Suisse, les régions périphériques se sentant abandonnées. Sort alors des tiroirs le concept d’horaire cadencé permettant une systématisation des correspondances. Bien que les vitesses maximales prévues ne changent pas, c’est un succès populaire.

In biology and chemistry, the transport of anions across lipid bilayer membranes is usually achieved by sophisticated supramolecular architectures. Significant size reduction of transporters is hampered by the intrinsically hydrophilic nature of typical anion-binding functionalities, hydrogen-bond donors or cations. To maximize the atom efficiency of anion transport, the hydrophobic nature, directionality, and strength of halogen bonds seem promising. Unlike the ubiquitous, structurally similar hydrogen bonds, halogen bonds have not been explored for anion transport. Here we report that transport across lipid bilayers can be achieved with small perfluorinated molecules that are equipped with strong halogen-bond donors. Transport is observed with trifluoroiodomethane (boiling point=−22 °C); that is, it acts as a 'single-carbon' transporter. Contrary to the destructive action of small-molecule detergents, transport with halogen bonds is leakage-free, cooperative, non-ohmic and highly selective, with anion/cation permeability ratios <37.

Facile access to complex systems is crucial to generate the functional materials of the future. Herein, we report self-organizing surface-initiated polymerization (SOSIP) as a user-friendly method to create ordered as well as oriented functional systems on transparent oxide surfaces. In SOSIP, self-organization of monomers and ring-opening disulfide exchange polymerization are combined to ensure the controlled growth of the polymer from the surface. This approach provides rapid access to thick films with smooth, reactivatable surfaces and long-range order with few defects and high precision, including panchromatic photosystems with oriented four-component redox gradients. The activity of SOSIP architectures is clearly better than that of disordered controls.

The transport of ions and molecules across lipid bilayer membranes connects cells and cellular compartments with their environment. This biological process is central to a host of functions including signal transduction in neurons and the olfactory and gustatory sensing systems, the translocation of biosynthetic intermediates and products, and the uptake of nutrients, drugs, and probes. Biological transport systems are highly regulated and selectively respond to a broad range of physical and chemical stimulation. A large percentage of today's drugs and many antimicrobial or antifungal agents take advantage of these systems. Other biological transport systems are highly toxic, such as the anthrax toxin or melittin from bee venom. For more than three decades, organic and supramolecular chemists have been interested in developing new transport systems. Over time, curiosity about the basic design has evolved toward developing of responsive systems with applications in materials sciences and medicine. Our early contributions to this field focused on the introduction of new structural motifs with emphasis on rigid-rod scaffolds, artificial β-barrels, or π-stacks. Using these scaffolds, we have constructed selective systems that respond to voltage, pH, ligands, inhibitors, or light (multifunctional photosystems). We have described sensing applications that cover the three primary principles of sensor development: immunosensors that use aptamers, biosensors (an "artificial" tongue), and differential sensors (an "artificial" nose). In this Account, we focus on our recent interest in applying synthetic transport systems as analytical tools to identify the functional relevance of less common noncovalent interactions, anion-π interactions, halogen bonds, and anion-macrodipole interactions. Anion-π interactions, the poorly explored counterpart of cation-π interactions, occur in aromatic systems with a positive quadrupole moment, such as TNT or hexafluorobenzene. To observe these elusive interactions in action, we synthesized naphthalenediimide transporters of increasing π-acidity up to an unprecedented quadrupole moment of +39 Buckinghams and characterized these systems in comparison with tandem mass spectrometry and computational simulations. With π-acidic calixarenes and calixpyrroles, we have validated our results on anion-π interactions and initiated our studies of halogen bonds. Halogen bonds originate from the σ-hole that appears on top of electron-deficient iodines, bromines, and chlorines. Halogen-bond donors are ideal for anion transport because they are as strong and at least as directional as hydrogen-bond donors, but also hydrophobic. The discovery of the smallest possible organic anion transporter, trifluoroiodomethane, illustrates the power of halogen-bond donors. This molecule contains a single carbon atom and is a gas with a boiling point of -22 °C. Anion-macrodipole interactions, finally, differ significantly from anion-π interactions and halogen bonds because they are important in nature and cannot be studied with small molecules. We have used anion-transporting peptide/urea nanotubes to examine these interactions in synthetic transport systems. To facilitate the understanding of the described results, we also include an in-depth discussion of the meaning of Hill coefficients. The use of synthetic transport systems to catch less common noncovalent interactions at work is important because it helps to expand the collection of interactions available to create functional systems. Progress in this direction furthers fundamental knowledge and invites many different applications. For illustration, we briefly discuss how this knowledge could apply to the development of new catalysts.

F rigid cats: The power of conformationally stabilized catalysts is demonstrated. By taking appropriate advantage of fluorine insertion (see scheme), purely conformational catalyst design led to a notable improvement in enantioselectivities from around 70 % to 91–98.5 % ee. The other advantage of this approach is the better understanding of the origin of the stereoselectivity in the given catalytic system. Detailed facts of importance to specialist readers are published as ”Supporting Information”. Such documents are peer-reviewed, but not copy-edited or typeset. They are made available as submitted by the authors. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.

Attractive in theory and confirmed to exist, anion-pi interactions have never really been seen at work. To catch them in action, we prepared a collection of monomeric, cyclic and rod-shaped naphthalenediimide transporters. Their ability to exert anion-pi interactions was demonstrated by electrospray tandem mass spectrometry in combination with theoretical calculations. To relate this structural evidence to transport activity in bilayer membranes, affinity and selectivity sequences were recorded. pi-acidification and active-site decrowding increased binding, transport and chloride > bromide > iodide selectivity, and supramolecular organization inverted acetate > nitrate to nitrate > acetate selectivity. We conclude that anion-pi interactions on monomeric surfaces are ideal for chloride recognition, whereas their supramolecular enhancement by pi,pi-interactions appears perfect to target nitrate. Chloride transporters are relevant to treat channelopathies, and nitrate sensors to monitor cellular signaling and cardiovascular diseases. A big impact on organocatalysis can be expected from the stabilization of anionic transition states on chiral pi-acidic surfaces.