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Atomically thin platinum diselenide (PtSe2) films are promising for applications in the fields of electronics, spintronics, and photodetectors owing to their tunable electronic structure and high carrier mobility. Using terahertz (THz) spectroscopy techniques, we investigated the layer-dependent semiconducting-to-metallic phase transition and associated intrinsic carrier dynamics in large-scale PtSe2films grown by molecular beam epitaxy. The uniformity of large-scale PtSe2films was characterized by spatially and frequency-resolved THz-based sheet conductivity mapping. Furthermore, we use an optical-pump-THz-probe technique to study the transport dynamics of photoexcited carriers and explore light-induced intergrain carrier transport in PtSe2films. We demonstrate large-scale THz-based mapping of the electrical properties of transition metal dichalcogenide films and show that the two noncontact THz-based approaches provide insight in the spatial and temporal properties of PtSe2films.

IMPORTANCE: Allocating resources to increase survival after cardiac arrest requires survivors to have a good quality of life, but long-term data are lacking. OBJECTIVE: To determine the quality of life of survivors of out-of-hospital cardiac arrest from 2001 to 2019. DESIGN, SETTING, AND PARTICIPANTS: This survey study used the EuroQol Health Questionnaire, 12-Item Short Form Health Survey (SF-12), and Hospital Anxiety and Depression Scale (HADS) to assess the health-related quality of life of all adult survivors of out-of-hospital cardiac arrest included in the Danish Cardiac Arrest Registry between June 1, 2001, and August 31, 2019, who were alive in October 2020 (follow-up periods, 0-1, >1-2, >2-4, >4-6, >6-8, >8-10, >10-15, and >15-20 years since arrest). The survey was conducted from October 1, 2020, through May 31, 2021. EXPOSURE: All patients who experienced an out-of-hospital cardiac arrest. MAIN OUTCOME AND MEASURES: Self-reported health was measured using the EuroQol Health Questionnaire index (EQ index) score and EQ visual analog scale. Physical and mental health were measured using the SF-12, and anxiety and depression were measured using the HADS. Descriptive statistics were used for the analysis. RESULTS: Of 4545 survivors, 2552 (56.1%) completed the survey, with a median follow-up since their event of 5.5 years (IQR, 2.9-8.9 years). Age was comparable between responders and nonresponders (median [IQR], 67 [58-74] years vs 68 [56-78] years), and 2075 responders (81.3%) were men and 477 (18.7%) women (vs 1473 male [73.9%] and 520 female [26.1%] nonresponders). For the shortest follow-up (0-1 year) and longest follow-up (>15-20 years) groups, the median EQ index score was 0.9 (IQR, 0.7-1.0) and 0.9 (0.8-1.0), respectively. For all responders, the mean (SD) SF-12 physical health score was 43.3 (12.3) and SF-12 mental health score, 52.9 (8.3). All 3 scores were comparable to a general Danish reference population. Based on HADS scores, a low risk for anxiety was reported by 73.0% (54 of 74) of 0- to 1-year survivors vs 89.3% (100 of 112) of greater than 15- to 20-year survivors; for symptoms of depression, these proportions were 79.7% (n = 59) and 87.5% (n = 98), respectively. Health-related quality of life was similar in survivor groups across all follow-up periods. CONCLUSIONS AND RELEVANCE: Among this survey study’s responders, who comprised more than 50% of survivors of out-of-hospital cardiac arrest in Denmark, long-term health-related quality of life up to 20 years after their event was consistently high and comparable to that of the general population. These findings support resource allocation and efforts targeted to increasing survival after out-of-hospital cardiac arrest.

RNA origami is a method for designing RNA nanostructures that can self-assemble through co-transcriptional folding with applications in nanomedicine and synthetic biology. However, to advance the method further, an improved understanding of RNA structural properties and folding principles is required. Here we use cryogenic electron microscopy to study RNA origami sheets and bundles at sub-nanometre resolution revealing structural parameters of kissing-loop and crossover motifs, which are used to improve designs. In RNA bundle designs, we discover a kinetic folding trap that forms during folding and is only released after 10 h. Exploration of the conformational landscape of several RNA designs reveal the flexibility of helices and structural motifs. Finally, sheets and bundles are combined to construct a multidomain satellite shape, which is characterized by individual-particle cryo-electron tomography to reveal the domain flexibility. Together, the study provides a structural basis for future improvements to the design cycle of genetically encoded RNA nanodevices.

Massive Dirac fermions are low-energy electronic excitations characterized by a hyperbolic band dispersion. They play a central role in several emerging physical phenomena such as topological phase transitions, anomalous Hall effects, and superconductivity. This work demonstrates that massive Dirac fermions can be controllably induced by lithographically patterning superstructures of nanoscale holes in a graphene device. Their band dispersion is systematically visualized using angle-resolved photoemission spectroscopy with nanoscale spatial resolution. A linear scaling of effective mass with feature sizes is reported, underlining the Dirac nature of the superstructures. In situelectrostatic doping dramatically enhances the effective hole mass and leads to the direct observation of an electronic band gap that results in a peak-to-peak band separation of 0.64 ± 0.03 eV, which is shown via first-principles calculations to be strongly renormalized by carrier-induced screening. The methodology demonstrates band structure engineering guided by directly viewing structurally and electrically tunable massive Dirac quasiparticles in lithographic superstructures at the nanoscale.

ABSTRACTThe Danish government has imposed numerous significant reforms in the employment policy field in recent years. One of the much-debated reforms is on social assistance. One of the specific intentions was a new look and strategy towards youth unemployment by introducing new categories. This leaves the discretion involved in categorization very much at the centre of the reform. This study explores and compares two job centres and the street level social workers discretion of young social assistance recipients. This article argues that the context of implementation affects the discretion carried out by the frontline professionals. Organizations are not just neutral mediators, because organization affects the output. Organizations tends to transform policy and become important in the daily judgement made by frontline professionals of what is correct professionalism. We argue that an implementation context characterized by paradigmatic implementation tends to categorize relatively more young clients as ‘ready for education’, whereas this is not the case for incremental implementation. In both cases, the adaptations of the reform are important. The choice of how to implement and how to organize the implementation of reforms influences the actual discretion. The caseworkers in both job centres are influenced by the organization wherein they work but at the same time have individual room for discretion. It seems as though the different kinds of implementation contexts affect how the individual caseworker mediates the legislation and becomes a policy mediator. The street level organization affects the output whereby they become mediators.

The correlation between the crystal structure of chemical vapor deposition (CVD)-grown graphene and the crystal structure of the Cu growth substrate and their mutual effect on the oxidation of the underlying Cu are systematically explored. We report that natural oxygen or water intercalation along the graphene–Cu interface results in an orientation-dependent oxidation rate of the Cu surface, particularly noticeable for bicrystal graphene domains on the same copper grain, suggesting that the relative crystal orientation of subgrains determines the degree of Cu oxidation. Atomistic force field calculations support these observations, showing that graphene domains have preferential alignment with the Cu(111) with a smaller average height above the global Cu surface as compared to intermediate orientations, and that this is the origin of the heterogeneous oxidation rate of Cu. This work demonstrates that the natural oxidation resistance of Cu coated by graphene is highly dependent on the crystal orientation and lattice alignment of Cu and graphene, which is key information for engineering the interface configuration of the graphene–Cu system for specific functionalities in mechanical, anticorrosion, and electrical applications of CVD-grown graphene.

We demonstrate a simple method for transferring large areas (up to A4-size sheets) of CVD graphene from copper foils onto a target substrate using a commercially available polyvinyl alcohol polymer foil as a carrier substrate and commercial hot-roll office laminator. Through the use of terahertz time-domain spectroscopy and Raman spectroscopy, large-area quantitative optical contrast mapping, and the fabrication and electrical characterization of ∼50 individual centimeter-scale van der Pauw field effect devices, we show a nondestructive technique to transfer large-area graphene with low residual doping that is scalable, economical, reproducible, and easy to use and that results in less doping and transfer-induced damage than etching or electrochemical delamination transfers. We show that the copper substrate can be used multiple times with minimal loss of material and no observable reduction in graphene quality. We have additionally demonstrated the transfer of multilayer hexagonal boron nitride from copper and iron foils. Finally, we note that this approach allows graphene to be supplied on stand-alone polymer supports by CVD graphene manufacturers to end users, with the only equipment and consumables required to transfer graphene onto target substrates being a commercial office laminator and water.

Two-dimensional materials such as graphene allow direct access to the entirety of atoms constituting the crystal. While this makes shaping by lithography particularly attractive as a tool for band structure engineering through quantum confinement effects, edge disorder and contamination have so far limited progress towards experimental realization. Here, we define a superlattice in graphene encapsulated in hexagonal boron nitride, by etching an array of holes through the heterostructure with minimum feature sizes of 12–15 nm. We observe a magnetotransport regime that is distinctly different from the characteristic Landau fan of graphene, with a sizeable bandgap that can be tuned by a magnetic field. The measurements are accurately described by transport simulations and analytical calculations. Finally, we observe strong indications that the lithographically engineered band structure at the main Dirac point is cloned to a satellite peak that appears due to moiré interactions between the graphene and the encapsulating material.

We study the oxidation of clean suspended mono- and few-layer graphene in real time by in situenvironmental transmission electron microscopy. At an oxygen pressure below 0.1 mbar, we observe anisotropic oxidation in which armchair-oriented hexagonal holes are formed with a sharp edge roughness below 1 nm. At a higher pressure, we observe an increasingly isotropic oxidation, eventually leading to irregular holes at a pressure of 6 mbar. In addition, we find that few-layer flakes are stable against oxidation at temperatures up to at least 1000 °C in the absence of impurities and electron-beam-induced defects. These findings show, first, that the oxidation behavior of mono- and few-layer graphene depends critically on the intrinsic roughness, cleanliness and any imposed roughness or additional reactivity from a supporting substrate and, second, that the activation energy for oxidation of pristine suspended few-layer graphene is up to 43% higher than previously reported for graphite. In addition, we have developed a cleaning scheme that results in the near-complete removal of hydrocarbon residues over the entire visible sample area. These results have implications for applications of graphene where edge roughness can critically affect the performance of devices and more generally highlight the surprising (meta)stability of the basal plane of suspended bilayer and thicker graphene toward oxidative environments at high temperature.

Epitaxial graphene is a promising route to wafer-scale production of electronic graphene devices. Chemical vapor deposition of graphene on silicon carbide offers epitaxial growth with layer control but is subject to significant spatial and wafer-to-wafer variability. We use terahertz time-domain spectroscopy and micro four-point probes to analyze the spatial variations of quasi-freestanding bilayer graphene grown on 4 in. silicon carbide (SiC) wafers and find significant variations in electrical properties across large regions, which are even reproduced across graphene on different SiC wafers cut from the same ingot. The dc sheet conductivity of epitaxial graphene was found to vary more than 1 order of magnitude across a 4 in. SiC wafer. To determine the origin of the variations, we compare different optical and scanning probe microscopies with the electrical measurements from nano- to millimeter scale and identify three distinct qualities of graphene, which can be attributed to the microstructure of the SiC surface.

We show that polar molecules (water, ammonia, and nitrogen dioxide) adsorbed solely at the exposed edges of an encapsulated graphene sheet exhibit ferroelectricity, collectively orienting and switching reproducibly between two available states in response to an external electric field. This ferroelectric molecular switching introduces drastic modifications to the graphene bulk conductivity and produces a large and ambipolar charge bistability in micrometer-size graphene devices. This system comprises an experimental realization of envisioned memory capacitive (“memcapacitive”) devices whose capacitance is a function of their charging history, here conceived via confined and correlated polar molecules at the one-dimensional edge of a two-dimensional crystal.

The mechanisms by which chemical vapor deposited (CVD) graphene and hexagonal boron nitride (h-BN) films can be released from a growth catalyst, such as widely used copper (Cu) foil, are systematically explored as a basis for an improved lift-off transfer. We show how intercalation processes allow the local Cu oxidation at the interface followed by selective oxide dissolution, which gently releases the 2D material (2DM) film. Interfacial composition change and selective dissolution can thereby be achieved in a single step or split into two individual process steps. We demonstrate that this method is not only highly versatile but also yields graphene and h-BN films of high quality regarding surface contamination, layer coherence, defects, and electronic properties, without requiring additional post-transfer annealing. We highlight how such transfers rely on targeted corrosion at the catalyst interface and discuss this in context of the wider CVD growth and 2DM transfer literature, thereby fostering an improved general understanding of widely used transfer processes, which is essential to numerous other applications.

SorCS2 is a member of the Vps10p-domain receptor gene family receptors with critical roles in the control of neuronal viability and function. Several genetic studies have suggested SORCS2to confer risk of bipolar disorder, schizophrenia and attention deficit-hyperactivity disorder. Here we report that hippocampal N-methyl-d-aspartate receptor-dependent synaptic plasticity is eliminated in SorCS2-deficient mice. This defect was traced to the ability of SorCS2 to form complexes with the neurotrophin receptor p75NTR, required for pro-brain-derived neurotrophic factor (BDNF) to induce long-term depression, and with the BDNF receptor tyrosine kinase TrkB to elicit long-term potentiation. Although the interaction with p75NTRwas static, SorCS2 bound to TrkB in an activity-dependent manner to facilitate its translocation to postsynaptic densities for synaptic tagging and maintenance of synaptic potentiation. Neurons lacking SorCS2 failed to respond to BDNF by TrkB autophosphorylation, and activation of downstream signaling cascades, impacting neurite outgrowth and spine formation. Accordingly, Sorcs2–/–mice displayed impaired formation of long-term memory, increased risk taking and stimulus seeking behavior, enhanced susceptibility to stress and impaired prepulse inhibition. Our results identify SorCS2 as an indispensable coreceptor for p75NTRand TrkB in hippocampal neurons and suggest SORCS2as the link between proBDNF/BDNF signaling and mental disorders.

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Culturing cells on gradient nanopatterns provides a useful tool to explore cellular adhesion to mimics of the extracellular matrix or screen for cellular responses to nanopatterns. A method is presented to fabricate complex gradient protein patterns based on hole-mask colloidal lithography, which can generate nanopatterns in multiple materials and of multiple shapes. Gradients of gold structures were functionalized to form gradients of protein nanopatterns of different shapes (bars, dot pairs, and rings), where a key parameter was systematically varied in each gradient. Cells were grown on vitronectin nanopatterns, showing differential adhesion (spread area/focal adhesion size) along the gradients.

AbstractThe article focuses upon the liturgical, monumental and literary staging of royal funerals in Denmark during the period 1526–1588. The seven cases analysed, reflecting both a transitional phase and the age of consolidation before and after the official institutionalization of the Lutheran Reformation in 1536, are read as equally exceptional and exemplary in a Protestant context. Attention in particular is given to various discourses on the value of traditions, on the display of magnificence versus the ideal of simplicity and on the Lutheran ideal of dissociation between the community of the dead and the living. In these issues, the royal funerals in several respects demonstrate the major power of continuity, especially during moments of crisis to the society deliberately stabilizing the changed status quothrough the incessantly significant reference to the legitimizing past.

We perform in-situ transmission electron microscopy (TEM) experiments of silver nanoparticles channeling on mono-, bi-, and few-layer graphene and discover that the interactions in the one-dimensional particle–graphene contact line are sufficiently strong so as to dictate the three-dimensional shape of the nanoparticles. We find a characteristic faceted shape in particles channeling along graphene ⟨100⟩ directions that is lost during turning and thus represents a dynamic equilibrium state of the graphene–particle system. We propose a model for the mechanism of zigzag edge formation and an explanation of the rate-limiting step for this process, supported by density functional theory (DFT) calculations, and obtain a good agreement between the DFT-predicted and experimentally obtained activation energies of 0.39 and 0.56 eV, respectively. Understanding the origin of the channels' orientation and the strong influence of the graphene lattice on the dynamic behavior of the particle morphology could be crucial for obtaining deterministic nanopatterning on the atomic scale.

Sub2p/UAP56 is a highly conserved DEAD-box RNA helicase involved in the packaging and nuclear export of mRNA. Here we analyze S. cerevisiaeSub2p functions in vivo and in vitro and find that a conserved N-terminal motif is required for mRNA export without affecting Sub2p helicase activity. Mutants in the helicase domain are trans-dominant negative and cause hyper-recombination.

Monolayer graphene oxide (mGO) is shown to effectively protect molecular thin films from reorganization and function as an atomically thin barrier for vapor-deposited Ti/Al metal top electrodes. Fragile organic Langmuir–Blodgett (LB) films of C22fatty acid cadmium salts (cadmium(II) behenate) were covered by a compressed mosaic LB film of mGO flakes. These hybrid LB films were examined with atomic force microscopy (AFM) and X-ray reflectivity, both with and without the metal top electrodes. While the AFM enabled surface and morphology analysis, the X-ray reflectivity allowed for a detailed structural depth profiling of the organic film and mGO layer below the metal top layers. The structure of the mGO-protected LB films was found to be perfectly preserved; in contrast, it has previously been shown that metal deposition completely destroys the first two LB layers of unprotected films. This study provides clear evidence of the efficient protection offered by a single atomic layer of GO.

Superhydrophobic silicon nanostructures were fabricated by anisotropic etching of silicon coated with a thin hydrophobic layer. At certain etch parameters, overhanging nanostructures form at the apexes of the rod-shaped tips. This leads to superoleophobic behavior for several oily liquids with contact angles up to 152° and roll-off angle down to 8°. Such nonlithographic nanoscale overhanging structures can also be added to silicon nanograss by deposition of a thin SiO2layer, which equips the silicon rods with 100−300 nm sized overhanging structures. This is a simple, fast, nonlithographic method for introducing amphiphobic behavior on a surface consisting of vertically aligned micro- or nanostructures.

The Sm and Sm-like proteins are conserved in all three domains of life and have emerged as important players in many different RNA-processing reactions. Their proposed role is to mediate RNA-RNA and/or RNA-protein interactions. In marked contrast to eukaryotes, bacteria appear to contain only one distinct Sm-like protein belonging to the Hfq family of proteins. Similarly, there are generally only one or two subtypes of Sm-related proteins in archaea, but at least one archaeon, Methanococcus jannaschii, encodes a protein that is related to Hfq. This archaeon does not contain any gene encoding a conventional archaeal Sm-type protein, suggesting that Hfq proteins and archaeal Sm-homologs can complement each other functionally. Here, we report the functional characterization of M. jannaschii Hfq and its crystal structure at 2.5 A resolution. The protein forms a hexameric ring. The monomer fold, as well as the overall structure of the complex is similar to that found for the bacterial Hfq proteins. However, clear differences are seen in the charge distribution on the distal face of the ring, which is unusually negative in M. jannaschii Hfq. Moreover, owing to a very short N-terminal alpha-helix, the overall diameter of the archaeal Hfq hexamer is significantly smaller than its bacterial counterparts. Functional analysis reveals that Escherichia coli and M. jannaschii Hfqs display very similar biochemical and biological properties. It thus appears that the archaeal and bacterial Hfq proteins are largely functionally interchangeable.