Charge transport mechanism in networks of armchair graphene nanoribbons.

In graphene nanoribbons (GNRs), the lateral confinement of charge carriers opens a band gap, the key feature that enables novel graphene-based electronics. Despite great progress, reliable and reproducible fabrication of single-ribbon field-effect transistors (FETs) is still a challenge, impeding the understanding of the charge transport. Here, we present reproducible fabrication of armchair GNR-FETs based on networks of nanoribbons and analyze the charge transport mechanism using nine-atom wide and, in particular, five-atom-wide GNRs with large conductivity.

Infections of Deep Neck Spaces.

Identifying infections of the deep neck spaces and understanding how they spread can be a diagnostic challenge that is complicated by complex anatomy and far-reaching clinical implications. Deep neck infections have the potential to quickly spread throughout the neck and chest, leading to widespread disease that can be rapidly fatal and resistant to treatment. This article provides a foundation for evaluating deep neck infections through a review of essential anatomy and a discussion of important diseases that interact with these spaces.

Amphiphilic Polyphenylene Dendron Conjugates for Surface Remodeling of Adenovirus 5.

Amphiphilic surface groups play an important role in many biological processes. The synthesis of amphiphilic polyphenylene dendrimer branches (dendrons), providing alternating hydrophilic and lipophilic surface groups and one reactive ethynyl group at the core is reported. The amphiphilic surface groups serve as biorecognition units that bind to the surface of adenovirus 5 (Ad5), which is a common vector in gene therapy.

On-Surface Dehydro-Diels-Alder Reaction of Dibromo-bis(phenylethynyl)benzene.

On-surface synthesis under ultrahigh vacuum conditions is a powerful tool to achieve molecular structures that cannot be accessed via traditional wet chemistry. Nevertheless, only a very limited number of chemical reactions out of the wide variety known from solution chemistry have been reported to proceed readily on atomically flat substrates. Cycloadditions are a class of reactions that are particularly important in the synthesis of sp-hybridized carbon-based nanostructures.

Topological Defect-Induced Magnetism in a Nanographene.

The on-surface reactions of 10-bromo-10'-(2,6-dimethylphenyl)-9,9'-bianthracene on Au(111) have been investigated by scanning tunneling microscopy and spectroscopy, complemented by theoretical calculations. The reactions afford the synthesis of two open-shell nanographenes ( and ) exhibiting different scenarios of all-carbon magnetism. , an all-benzenoid nanographene with triangulene-like termini, contains a high proportion of zigzag edges which endows it with a low frontier gap and edge-localized states.

Doping free transfer of graphene using aqueous ammonia flow.

Doping-free transfer of graphene produced by catalytic chemical vapor deposition (CVD) on copper foil, is still a technical challenge since unintentional doping of the transferred graphene layer yields an uncontrolled shift of Dirac point in graphene-based field-effect transistors (FETs). Typically, CVD graphene is released from the growth template by etching of the template, copper. During the etching process, ions adhere to the graphene layer resulting in unintentional doping.

5,6,12,13-Tetraazaperopyrenes as Unique Photonic and Mechanochromic Fluorophores.

5,6,12,13-Tetraazaperopyrenes with different number of tert-butyl groups (c-TAPP-T, c-TAPP-H) were synthesized, via four-fold Bischler-Napieralski cyclization as the key step. As deduced from the single-crystal structures and optical properties, N-doping and substitution type allow for a precise control of intermolecular interactions. Compared to the reported 1,3,8,10-tetraazaperopyrenes, significantly different packing modes were found in 5,6,12,13-tetraazaperopyrenes.

Publisher Correction: Topological frustration induces unconventional magnetism in a nanographene.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Tetrapodal Diazatriptycene Enforces Orthogonal Orientation in Self-Assembled Monolayers.

Conformationally rigid multipodal molecules should control the orientation and packing density of functional head groups upon self-assembly on solid supports. Common tripods frequently fail in this regard because of inhomogeneous bonding configuration and stochastic orientation. These issues are circumvented by a suitable tetrapodal diazatriptycene moiety, bearing four thiol-anchoring groups, as demonstrated in the present study.

Topological frustration induces unconventional magnetism in a nanographene.

The chemical versatility of carbon imparts manifold properties to organic compounds, where magnetism remains one of the most desirable but elusive. Polycyclic aromatic hydrocarbons, also referred to as nanographenes, show a critical dependence of electronic structure on the topologies of the edges and the π-electron network, which makes them model systems with which to engineer unconventional properties including magnetism. In 1972, Erich Clar envisioned a bow-tie-shaped nanographene, CH (refs.

Synthesis of Circumpyrene by Alkyne Benzannulation of Brominated Dibenzo[,]ovalene.

A transition-metal catalyzed alkyne benzannulation allowed an unprecedented synthesis of circumpyrene, starting from 3,11-dibromo-6,14-dimesityldibenzo[,]ovalene (DBOV). The circumpyrene was characterized by a combination of NMR, mass spectrometry, and single-crystal X-ray diffraction analysis, revealing its multizigzag-edged structure. Two newly introduced C═C bonds in circumpyrene strongly perturbed the electronic structures of DBOV, as evidenced by increased optical and electrochemical energy gaps.

Quantum units from the topological engineering of molecular graphenoids.

Robustly coherent spin centers that can be integrated into devices are a key ingredient of quantum technologies. Vacancies in semiconductors are excellent candidates, and theory predicts that defects in conjugated carbon materials should also display long coherence times. However, the quantum performance of carbon nanostructures has remained stunted by an inability to alter the sp-carbon lattice with atomic precision.

Unmet Need for Workplace Accommodation.

We use experimental survey methods in a nationally representative survey to test alternative ways of identifying (1) individuals in the population who would be better able to work if they received workplace accommodation for a health condition; (2) the rate at which these individuals receive workplace accommodation; and (3) the rate at which accommodated workers are still working four years later, compared to similar workers who were not accommodated. We find that question order in disability surveys matters. We present suggestive evidence of priming effects that lead people to understate accommodation when first asked about work-limiting health problems.

Kinetic Ionic Permeation and Interfacial Doping of Supported Graphene.

Due to its outstanding electrical properties and chemical stability, graphene finds widespread use in various electrochemical applications. Although the presence of electrolytes strongly affects its electrical conductivity, the underlying mechanism has remained elusive. Here, we employ terahertz spectroscopy as a contact-free means to investigate the impact of ubiquitous cations (Li, Na, K, and Ca) in aqueous solution on the electronic properties of SiO-supported graphene.

Understanding and improving the experience of claiming social security for mental health problems in the west of Scotland: A participatory social welfare study.

A growing body of literature links claimant interactions with the UK social security system and negative psychological consequences. Psychologists for social change developed a framework to outline proposed mechanisms of psychological impact from austerity. This codesigned study aimed to make an informed comment on areas of dis(agreement) between the Austerity Ailments framework and how people claiming for mental health problems describe their own experiences.

Nanographenes: Ultrastable, Switchable, and Bright Probes for Super-Resolution Microscopy.

Super-resolution fluorescence microscopy has enabled important breakthroughs in biology and materials science. Implementations such as single-molecule localization microscopy (SMLM) and minimal emission fluxes (MINFLUX) microscopy in the localization mode exploit fluorophores that blink, i.e.

Smoking behaviour among nurses in Ontario: cross-sectional results from the Champlain Nurses' Study.

Objective: Nurses comprise the largest professional group within the Canadian health care workforce. We aimed to assess the prevalence and correlates of smoking among nurses.

Methods: The Champlain Nurses' Study was a multi-centre, observational study that evaluated the physical activity levels and health of hospital-based nurses.

Surface-Specific Spectroscopy of Water at a Potentiostatically Controlled Supported Graphene Monolayer.

Knowledge of the structure of interfacial water molecules at electrified solid materials is the first step toward a better understanding of important processes at such surfaces, in, e.g., electrochemistry, atmospheric chemistry, and membrane biophysics.

Dibenzo[,]ovalene as Highly Luminescent Nanographene: Efficient Synthesis via Photochemical Cyclodehydroiodination, Optoelectronic Properties, and Single-Molecule Spectroscopy.

Dibenzo[,]ovalene (DBOV), as a new nanographene, has demonstrated promising optical properties, such as red emission with a high fluorescence quantum yield of 79% and stimulated emission, as well as high thermal stability and photostability, which indicated its promise as a light-emitting and optical gain material. However, the previous synthetic routes required at least 12 steps. This obstructed access to different derivatives, e.

A Universal Length-Dependent Vibrational Mode in Graphene Nanoribbons.

Graphene nanoribbons (GNRs) have attracted considerable interest, as their atomically tunable structure makes them promising candidates for future electronic devices. However, obtaining detailed information about the length of GNRs has been challenging and typically relies on low-temperature scanning tunneling microscopy. Such methods are ill-suited for practical device application and characterization.

Performance Obligations to Improve Delivery of Hospital-Initiated Smoking Cessation Interventions: A Before-and-After Evaluation.

Introduction: This study evaluated whether introducing performance obligations (a policy intervention) to service agreements between hospitals (n = 15) and their local health authority: (1) improved provision of an evidence-based tobacco cessation intervention (the "Ottawa Model" for Smoking Cessation) and (2) changed the quality of the cessation intervention being delivered.

Methods: Interrupted time series analysis was used to evaluate the change in the proportion of smoker patients provided the Ottawa Model 3 years before and 3 years after introducing the performance obligations. Changes in secondary outcomes related to program quality were described using mean differences, risk differences, and risk ratios, as appropriate.

Heteroatom-Doped Nanographenes with Structural Precision.

Nanographenes, which are defined as nanoscale (1-100 nm) graphene cutouts, include quasi-one-dimensional graphene nanoribbons (GNRs) and quasi-zero-dimensional graphene quantum dots (GQDs). Polycyclic aromatic hydrocarbons (PAHs) larger than 1 nm can be viewed as GQDs with atomically precise molecular structures and can thus be termed nanographene molecules. As a result of quantum confinement, nanographenes are promising for next-generation semiconductor applications with finite band gaps, a significant advantage compared with gapless two-dimensional graphene.

Tailoring the Emission of Fluorinated Bipyridine-Chelated Iridium Complexes.

New functionalized tris(2',6'-difluoro-2,3'-bipyridinato-,C4')iridium(III) ((dfpypy)Irs) complexes, including small molecules and their dendrimer embedded analogoues, were synthesized and characterized. It is demonstrated that both the -(dfpypy)Ir-based polyphenylene dendrimers and (triisopropylsilyl)ethynyl (TIPSE)-substituted (dfpypy)Ir complexes induce large bathochromic shifts (∼50 nm) of emission bands compared with -(dfpypy)Ir. This is due to the pronounced π-π* character of emissive excited states and the extended conjugation.

Charging OBO-Fused Double [5]Helicene with Electrons.

Chemical reduction of OBO-fused double[5]helicene with Group 1 metals (Na and K) has been investigated for the first time. Two doubly-reduced products have been isolated and structurally characterized by single-crystal X-ray diffraction, revealing a solvent-separated ion triplet (SSIT) with Na ions and a contact-ion pair (CIP) with K ion. As the key structural outcome, the X-ray crystallographic analysis discloses the consequences of adding two electrons to the double helicene core in the SSIT without metal binding and reveals the preferential binding site in the CIP with K counterions.