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Self-assembled terephthalic acid adlayers on a Cu(100) surface is studied by X-ray photoelectron spectroscopy, near-edge X-ray absorption fine structure, and scanning tunneling microscopy in the temperature range 190-400K under ultrahigh vacuum conditions. Three distinct well-ordered phases observed evolving with increasing temperature is explained.

In this work, a Mg(0001) single crystal is used as a novel template to grow 2D supramolecular nano-architectures. By using scanning tunnelling microscopy (STM) and high-resolution X-ray photoemission spectroscopy (HR-XPS), the formation of either a homo-molecular or metal–organic network is reported for carboxylic or amino functionalized molecules, respectively. [ABSTRACT FROM AUTHOR]

We show that Sn atoms combined with organic ligands can be used to build 2D coordination networks on Au(111) surfaces. [ABSTRACT FROM AUTHOR]

A Scanning Tunneling Microscope (STM) is used to induce a reversible transition between different polymorphs in a binary supramolecular network at the liquid/solid interface. The transition is driven externally by switching the polarity of the sample by positive or negative sample bias potentials. We demonstrate that by mixing bias-sensitive and non-sensitive molecules, we gain access to a variety of binary porous structures that can be prepared and reliably actuated for each relative concentration. [ABSTRACT FROM AUTHOR]

Abstract: At Danum Valley, Sabah, dipterocarp forest is affected by moderately-strong droughts which perturb the ecosystem. Analysing stem growth for c. 3700 understorey trees (12.5–<50cm girth), measured over four periods (between 1986 and 2007), response to an ENSO-related event (1998) was followed. Relative growth rates (rgr) of the 48 most abundant species in the size class were considered individually, and as relative changes between periods. From them a measure reactivity was derived. Whilst a third of species differed from one another in rgr, within-species rates were highly variable: often species had very different (pluralistic) response patterns over time. The rgr decreased in the drought period, increased and overcompensated directly afterwards, and later returned to original levels. The forest displayed moderate resistance, and high resilience and stability within c. 4years of the perturbation. Oscillatory responses were more pronounced among true understorey species than among small trees of overstorey ones, suggesting that the former might play a key role in stabilization. Environmental stochasticity in the form of coloured noise may therefore be causing a major part of the variation in rain forest dynamics and explain its complexity. [Copyright &y& Elsevier]

Emerging digital technologies promise to improve breast cancer care, however lack of awareness among clinicians often prevents timely adoption. This study aims to investigate current awareness and intention-to-use of three technologies among breast cancer healthcare professionals (HCP): (1) digital health applications (DHA), (2) artificial intelligence (AI), and (3) blockchain technology (BC). A 22-item questionnaire was designed and administered before and after a 30 min educational presentation highlighting technology implementation examples. Technology awareness and intention-to-use were measured using 7-point Likert scales. Correlations between demographics, technology awareness, intention-to-use, and eHealth literacy (GR-eHEALS scale) were analyzed. 45 HCP completed the questionnaire, of whom 26 (57.8%) were female. Age ranged from 24 to 67 {mean age (SD): 44.93 ± 12.62}. Awareness was highest for DHA (68.9%) followed by AI (66.7%) and BC (24.4%). The presentation led to a non-significant increase of intention-to-use AI {5.37 (±1.81) to 5.83 (±1.64)}. HCPs´ intention-to-use BC after the presentation increased significantly {4.30 (±2.04) to 5.90 (±1.67), p  < 0.01}. Mean accumulated score for GR-eHEALS averaged 33.04 (± 6.61). HCPs´ intended use of AI significantly correlated with eHealth literacy (ρ = 0.383; p  < 0.01), intention-to-use BC (ρ = 0.591; p  < 0.01) and participants´ age (ρ = -0.438; p  < 0.01). This study demonstrates the effect that even a short practical presentation can have on HCPs´ intention-to-use emerging digital technologies. Training potential professional users should be addressed alongside the development of new information technologies and is crucial to increase HCPs´ corresponding awareness and intended use., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Griewing, Knitza, Gremke, Wallwiener, Wagner, Lingenfelder and Kuhn.)

Magnetic field effects on electrocatalysis have recently gained attention due to the substantial enhancement of the oxygen evolution reaction (OER) on ferromagnetic catalysts. When detecting an enhanced catalytic activity, the effect of magnetic fields on mass transport must be assessed. In this study, we employ a specifically designed magneto-electrochemical system and non-magnetic electrodes to quantify magnetic field effects. Our findings reveal a marginal enhancement in reactions with high reactant availability, such as the OER, whereas substantial boosts exceeding 50% are observed in diffusion limited reactions, exemplified by the oxygen reduction reaction (ORR). Direct visualization and quantification of the whirling motion of ions under a magnetic field underscore the importance of Lorentz forces acting on the electrolyte ions, and demonstrate that bubbles' movement is a secondary phenomenon. Our results advance the fundamental understanding of magnetic fields in electrocatalysis and unveil new prospects for developing more efficient and sustainable energy conversion technologies., (© 2024. The Author(s).)

Controlling product selectivity is essential for improving the efficiency of multi-product reactions. Electrochemical water oxidation is a reaction of main importance in different applications, e.g., renewable energy schemes and environmental protection, where H2O2 and O2 are the two principal products. In this Communication, the product selectivity of electrochemical water oxidation was controlled by making use of the chiral induced spin selectivity (CISS) effect at mesoporous-TiO2 on the molecule-modified Au substrate. Our results show a decrease in H2O2 formation when using chiral hetero-helicene molecules adsorbed on the Au substrate. We propose a mechanism for this kinetic effect based on the onset of CISS-induced spin polarization on the Au-helicene chiral interface. We also present a new tunable substrate to investigate the CISS mechanism., (© 2024 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).)

The reversible formation of hydrogen bonds is a ubiquitous mechanism for controlling molecular assembly in biological systems. However, achieving predictable reversibility in artificial two-dimensional (2D) materials remains a significant challenge. Here, we use an external electric field (EEF) at the solid/liquid interface to trigger the switching of H-bond-linked 2D networks using a scanning tunneling microscope. Assisted by density functional theory and molecular dynamics simulations, we systematically vary the molecule-to-molecule interactions, i.e., the hydrogen-bonding strength, as well as the molecule-to-substrate interactions to analyze the EEF switching effect. By tuning the building block's hydrogen-bonding ability (carboxylic acids vs aldehydes) and substrate nature and charge (graphite, graphene/Cu, graphene/SiO 2 ), we induce or freeze the switching properties and control the final polymorphic output in the 2D network. Our results indicate that the switching ability is not inherent to any particular building block but instead relies on a synergistic combination of the relative adsorbate/adsorbate and absorbate/substrate energetic contributions under surface polarization. Furthermore, we describe the dynamics of the switching mechanism based on the rotation of carboxylic groups and proton exchange, which generate the polarizable species that are influenced by the EEF. This work provides insights into the design and control of reversible molecular assembly in 2D materials, with potential applications in a wide range of fields, including sensors and electronics.

With the recent diffusion of access to publicly available large language models (LLMs), common interest in generative artificial-intelligence-based applications for medical purposes has skyrocketed. The increased use of these models by tech-savvy patients for personal health issues calls for a scientific evaluation of whether LLMs provide a satisfactory level of accuracy for treatment decisions. This observational study compares the concordance of treatment recommendations from the popular LLM ChatGPT 3.5 with those of a multidisciplinary tumor board for breast cancer (MTB). The study design builds on previous findings by combining an extended input model with patient profiles reflecting patho- and immunomorphological diversity of primary breast cancer, including primary metastasis and precancerous tumor stages. Overall concordance between the LLM and MTB is reached for half of the patient profiles, including precancerous lesions. In the assessment of invasive breast cancer profiles, the concordance amounts to 58.8%. Nevertheless, as the LLM makes considerably fraudulent decisions at times, we do not identify the current development status of publicly available LLMs to be adequate as a support tool for tumor boards. Gynecological oncologists should familiarize themselves with the capabilities of LLMs in order to understand and utilize their potential while keeping in mind potential risks and limitations.

Sequential socioeconomic shocks, including the COVID-19 pandemic, economic recession, or energy and refugee crises in the face of violent conflicts, have led to the failure of healthcare systems in Europe. Against this background, the aim of this study was to evaluate the resilience of regional gynecological and obstetric inpatient care using the example of a regional core medical provider in central Germany. Base data were retrieved from Marburg University Hospital and underwent standardized calculation and descriptive statistical assessment pursuant to the aG-DRG catalog. The data illustrate a decline in the average length of patient stays and average case complexity in combination with increasing patient turnover for the six-year observation period of 2017-2022. Core profitability of the departments of gynecology and obstetrics deteriorated in the year of 2022. The results suggest weakened resilience of gynecological and obstetrics inpatient care in the setting of a regional core medical provider in central Germany and indicate how it may have failed in core economic profitability. This is consistent with predictions about the lack of resilience of health systems and the critical economic situation of German hospitals in the face of ongoing socioeconomic shocks that collaterally endanger women's health care., Competing Interests: The authors declare that they have no conflict of interest.

Purpose: The goal of this study is to examine the chronological development of hospitalized oncology and COVID-19 patients, and compare effects on oncology sub-disciplines for pre-pandemic (2017-19) and pandemic (2020-21) years in the setting of a German university maximum care provider., Methods: Data were retrospectively retrieved from the hospital performance controlling system for patient collectives with oncological main (n Onco ) and COVID-19 secondary diagnosis (n COVID-19 ). Data analysis is based on descriptive statistical assessment., Results: The oncology patient collective (n Onco  = 27,919) shows a decrease of hospitalized patients for the whole pandemic (- 4% for 2020 and - 2,5% for 2021 to 2019). The number of hospitalized COVID-19 patients increases from first to second pandemic year by + 106.71% (n COVID-19  = 868). Maximum decline in monthly hospitalized oncology patients amounts to - 19% (May 2020) during the first and - 21% (December 2020) during the second lockdown. Relative monthly hospitalization levels of oncology patients reverted to pre-pandemic levels from February 2021 onwards., Conclusion: The results confirm a decline in hospitalized oncology patients for the entire pandemic in the setting of a maximum care provider. Imposed lockdown and contact restrictions, rising COVID-19 case numbers, as well as discovery of new virus variants have a negative impact on hospitalized treated oncological patients., (© 2022. The Author(s).)

The study pursues the objective of drawing a comparison between the data of gyne-oncology, gynecology, and obstetrics patient collectives of a German university hospital regarding the progression of patient number and corresponding treatment data during the five-year period of 2017-2021 to assess the impact of the COVID-19 pandemic on gyne-oncological treatment. Descriptive assessment is based on data extracted from the database of the hospital controlling system QlikView ® for patients hospitalized at the Department of Gynecology and Obstetrics of Marburg University Hospital. Gynecology and gyne-oncology experience a maintained decline in patient number (n Gynecology : -6% 2019 to 2020, -5% 2019 to 2021; n Gyne-Oncology : -6% 2019 to 2020, -2% 2019 to 2021) with varying effects on the specific gyne-oncological main diagnoses. Treatment parameters remain unchanged in relative assessment, but as gyne-oncology constitutes the dominating revenue contributor in gynecology (35.1% of patients, 52.9% of revenue, 2021), the extent of the decrease in total revenue (-18%, 2019 to 2020, -14%, 2019 to 2021) surpasses the decline in patient number. The study displays a negative impact on the gynecology care situation of a German university hospital for the entire pandemic, with an even greater extent on gyne-oncology. This development not only endangers the quality of medical service provision but collaterally pressurizes gynecology service providers.

This study aims at evaluating the use case potential of breast cancer care for artificial intelligence and blockchain technology application based on the patient data analysis at Marburg University Hospital and, thereupon, developing a digital workflow for breast cancer care. It is based on a retrospective descriptive data analysis of all in-patient breast and ovarian cancer patients admitted at the Department of Gynecology of Marburg University Hospital within the five-year observation period of 2017 to 2021. According to the German breast cancer guideline, the care workflow was visualized and, thereon, the digital concept was developed, premised on the literature foundation provided by a Boolean combination open search. Breast cancer cases display a lower average patient case complexity, fewer secondary diagnoses, and performed procedures than ovarian cancer. Moreover, 96% of all breast cancer patients originate from a city with direct geographical proximity. Estimated circumference and total catchment area of ovarian present 28.6% and 40% larger, respectively, than for breast cancer. The data support invasive breast cancer as a preferred use case for digitization. The digital workflow based on combined application of artificial intelligence as well as blockchain or distributed ledger technology demonstrates potential in tackling senological care pain points and leveraging patient data safety and sovereignty., Competing Interests: The authors declare that they have no conflict of interest.

Time-series data offer a way of investigating the causes driving ecological processes as phenomena. To test for possible differences in water relations between species of different forest structural guilds at Danum (Sabah, NE Borneo), daily stem girth increments (gthi), of 18 trees across six species were regressed individually on soil moisture potential (SMP) and temperature (TEMP), accounting for temporal autocorrelation (in GLS-arima models), and compared between a wet and a dry period. The best-fitting significant variables were SMP the day before and TEMP the same day. The first resulted in a mix of positive and negative coefficients, the second largely positive ones. An adjustment for dry-period showers was applied. Interactions were stronger in dry than wet period. Negative relationships for overstorey trees can be interpreted in a reversed causal sense: fast transporting stems depleted soil water and lowered SMP. Positive relationships for understorey trees meant they took up most water at high SMP. The unexpected negative relationships for these small trees may have been due to their roots accessing deeper water supplies (if SMP was inversely related to that of the surface layer), and this was influenced by competition with larger neighbour trees. A tree-soil flux dynamics manifold may have been operating. Patterns of mean diurnal girth variation were more consistent among species, and time-series coefficients were negatively related to their maxima. Expected differences in response to SMP in the wet and dry periods did not clearly support a previous hypothesis differentiating drought and non-drought tolerant understorey guilds. Trees within species showed highly individual responses when tree size was standardized. Data on individual root systems and SMP at several depths are needed to get closer to the mechanisms that underlie the tree-soil water phenomena in these tropical forests. Neighborhood stochasticity importantly creates varying local environments experienced by individual trees., Competing Interests: The authors have declared that no competing interests exist.

A sustainable future requires highly efficient energy conversion and storage processes, where electrocatalysis plays a crucial role. The activity of an electrocatalyst is governed by the binding energy towards the reaction intermediates, while the scaling relationships prevent the improvement of a catalytic system over its volcano-plot limits. To overcome these limitations, unconventional methods that are not fully determined by the surface binding energy can be helpful. Here, we use organic chiral molecules, i.e., hetero-helicenes such as thiadiazole-[7]helicene and bis(thiadiazole)-[8]helicene, to boost the oxygen evolution reaction (OER) by up to ca. 130 % (at the potential of 1.65 V vs. RHE) at state-of-the-art 2D Ni- and NiFe-based catalysts via a spin-polarization mechanism. Our results show that chiral molecule-functionalization is able to increase the OER activity of catalysts beyond the volcano limits. A guideline for optimizing the catalytic activity via chiral molecular functionalization of hybrid 2D electrodes is given., (© 2022. The Author(s).)

Einleitung Die COVID-19-Pandemie bedeutet einschneidende Maßnahmen für das nationale Gesundheitssystem. Dies bot den Anlass, die klinischen und ökonomischen Leistungsindikatoren der gynäkologischen und geburtshilflichen Versorgung des Universitätsklinikums Marburg als regionaler universitärer Maximalversorger zu analysieren. Hierzu wurden die Auswirkungen auf die monatlichen stationären und ambulanten Fallzahlvolumina sowie die entsprechenden ICD- und DRG-Kodierungen ausgewertet, um etwaige Versorgungsdefizite aufzudecken. Material und Methoden Die Studie basiert auf einer retrospektiven Datenanalyse therapierter stationären und ambulanten Fälle der Jahre 2016 bis 2020. Hierzu wurden über das klinikinterne Leistungscontrolling-Programm QlikView die Daten von 9487 Fällen der Klinik für Gynäkologie und 19597 Fällen der Klinik für Geburtshilfe ausgewertet. Ergebnisse Es bildet sich eine der nationalen Pandemiedynamik folgende Abnahme der gynäkologischen stationären Fallzahlen um -6% ab, während das geburtshilfliche Fallzahlvolumen um +11% im Jahr 2020 steigt. Insgesamt fallen die Effekte für die ambulante Versorgung geringer aus. Zudem lässt sich eine standortbezogene Abnahme der C50 "Bösartige Neubildungen der Brustdrüse" und C56 "Bösartige Ovarialtumoren" Diagnosen um -7,4% bzw. -14% feststellen. Eine Rückkehr zu dem Leistungsniveau des Vorjahres konnte im ambulanten in 3 und im stationären Sektor in 5 Monaten erreicht werden. Schlussfolgerung Die negativen Auswirkungen der COVID-19-Pandemie treffen vorwiegend die Klinik für Gynäkologie. Durch das Vertrauen in die Sicherheit der universitären Versorgung und das Serviceangebot, werdende Väter nach Schnelltestung am Geburtsprozess teilhaben zu lassen, konnte eine Fallzunahme in der Geburtshilfe erreicht werden. Die Rückkehr zu präpandemischen Leistungsniveaus gestaltet sich weiterhin schleppend, während sich der ohnehin weniger betroffene ambulante Sektor zügiger erholt. Der standortbezogene Rückgang der Diagnosen C50 und C56 ist besorgniserregend und bedarf epidemiologischer Aufarbeitung. Die fallzahlbezogenen Auswirkungen der Pandemie bilden sich gleichsam in den ökonomischen Leistungskennzahlen ab., Competing Interests: Conflict of Interest The authors declare that they have no conflict of interest., (The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution-NonDerivative-NonCommercial-License, permitting copying and reproduction so long as the original work is given appropriate credit. Contents may not be used for commercial purposes, or adapted, remixed, transformed or built upon. (https://creativecommons.org/licenses/by-nc-nd/4.0/).)

Immense field enhancement and nanoscale confinement of light are possible within nanoparticle-on-mirror (NPoM) plasmonic resonators, which enable novel optically activated physical and chemical phenomena and render these nanocavities greatly sensitive to minute structural changes, down to the atomic scale. Although a few of these structural parameters, primarily linked to the nanoparticle and the mirror morphology, have been identified, the impact of molecular assembly and organization of the spacer layer between them has often been left uncharacterized. Here, we experimentally investigate how the complex and reconfigurable nature of a thiol-based self-assembled monolayer (SAM) adsorbed on the mirror surface impacts the optical properties of the NPoMs. We fabricate NPoMs with distinct molecular organizations by controlling the incubation time of the mirror in the thiol solution. Afterward, we investigate the structural changes that occur under laser irradiation by tracking the bonding dipole plasmon mode, while also monitoring Stokes and anti-Stokes Raman scattering from the molecules as a probe of their integrity. First, we find an effective decrease in the SAM height as the laser power increases, compatible with an irreversible change of molecule orientation caused by heating. Second, we observe that the nanocavities prepared with a densely packed and more ordered monolayer of molecules are more prone to changes in their resonance compared to samples with sparser and more disordered SAMs. Our measurements indicate that molecular orientation and packing on the mirror surface play a key role in determining the stability of NPoM structures and hence highlight the under-recognized significance of SAM characterization in the development of NPoM-based applications., Competing Interests: The authors declare no competing financial interest., (© 2021 The Authors. Published by American Chemical Society.)

Plasmonic nanojunctions, consisting of adjacent metal structures with nanometre gaps, can support localised plasmon resonances that boost light matter interactions and concentrate electromagnetic fields at the nanoscale. In this regime, the optical response of the system is governed by poorly understood dynamical phenomena at the frontier between the bulk, molecular and atomic scales. Here, we report ubiquitous spectral fluctuations in the intrinsic light emission from photo-excited gold nanojunctions, which we attribute to the light-induced formation of domain boundaries and quantum-confined emitters inside the noble metal. Our data suggest that photoexcited carriers and gold adatom - molecule interactions play key roles in triggering luminescence blinking. Surprisingly, this internal restructuring of the metal has no measurable impact on the Raman signal and scattering spectrum of the plasmonic cavity. Our findings demonstrate that metal luminescence offers a valuable proxy to investigate atomic fluctuations in plasmonic cavities, complementary to other optical and electrical techniques.

Transition metal dichalcogenides (TMDs) represent a class of semiconducting two-dimensional (2D) materials with exciting properties. In particular, defects in 2D-TMDs and their molecular interactions with the environment can crucially affect their physical and chemical properties. However, mapping the spatial distribution and chemical reactivity of defects in liquid remains a challenge. Here, we demonstrate large area mapping of reactive sulfur-deficient defects in 2D-TMDs in aqueous solutions by coupling single-molecule localization microscopy with fluorescence labeling using thiol chemistry. Our method, reminiscent of PAINT strategies, relies on the specific binding of fluorescent probes hosting a thiol group to sulfur vacancies, allowing localization of the defects with an uncertainty down to 15 nm. Tuning the distance between the fluorophore and the docking thiol site allows us to control Föster resonance energy transfer (FRET) process and reveal grain boundaries and line defects due to the local irregular lattice structure. We further characterize the binding kinetics over a large range of pH conditions, evidencing the reversible adsorption of the thiol probes to the defects with a subsequent transitioning to irreversible binding in basic conditions. Our methodology provides a simple and fast alternative for large-scale mapping of nonradiative defects in 2D materials and can be used for in situ and spatially resolved monitoring of the interaction between chemical agents and defects in 2D materials that has general implications for defect engineering in aqueous condition.

The electroreduction of CO 2 (CO 2 RR) is a promising strategy toward sustainable fuels. Cu is the only Earth-abundant and pure metal capable of catalyzing CO 2 -to-hydrocarbons conversion with significant Faradaic efficiencies; yet, its dynamic structure under operando CO 2 RR conditions remains unknown. Here, we track the Cu structure operando by electrochemical scanning tunneling microscopy and Raman spectroscopy. Surprisingly, polycrystalline Cu surfaces reconstruct forming Cu nanocuboids whose size can be controlled by the polarization potential and the time employed in their in situ synthesis, without the assistance of organic surfactants and/or halide anions. If the Cu surface is covered by a graphene monolayer, smaller features with enhanced catalytic activity for CO 2 RR can be prepared. The graphene-protecting layer softens the 3D morphological changes that Cu-based catalysts suffer when exposed to aggressive electrochemical environments and allows us to track the kinetic roughening process. This novel strategy is promising for improving Cu long-term stability, and consequently, it could be used as a platform to ultimately control product selectivity.

Inert single-layer boron nitride (h-BN) grown on a catalytic metal may be functionalized with quaternary ammonium compounds (quats) that are widely used as nonreactive electrolytes. We observe that the quat treatment, which facilitates the electrochemical transfer of two-dimensional materials, involves a decomposition of quat ions and leads to covalently bound quat derivatives on top of the 2D layer. Applying tetraoctylammonium and h-BN on rhodium, the reaction product is top-alkylized h-BN as identified with high-resolution X-ray photoelectron spectroscopy. The alkyl chains are homogeneously distributed across the surface, and the properties thereof are well-tunable by the choice of different quats. The functionalization further weakens the 2D material-substrate interaction and promotes easy transfer. Therefore, the functionalization scheme that is presented enables the design of 2D materials with tailored properties and with the freedom to position and orient them as required. The mechanism of this functionalization route is investigated with density functional theory calculations, and we identify the proximity of the catalytic metal substrate to alter the chemical reactivity of otherwise inert h-BN layers.

Nickel iron oxide is considered a benchmark nonprecious catalyst for the oxygen evolution reaction (OER). However, the nature of the active site in nickel iron oxide is heavily debated. Here we report direct spectroscopic evidence for the different active sites in Fe-free and Fe-containing Ni oxides. Ultrathin layered double hydroxides (LDHs) were used as defined samples of metal oxide catalysts, and 18 O-labeling experiments in combination with in situ Raman spectroscopy were employed to probe the role of lattice oxygen as well as an active oxygen species, NiOO - , in the catalysts. Our data show that lattice oxygen is involved in the OER for Ni and NiCo LDHs, but not for NiFe and NiCoFe LDHs. Moreover, NiOO - is a precursor to oxygen for Ni and NiCo LDHs, but not for NiFe and NiCoFe LDHs. These data indicate that bulk Ni sites in Ni and NiCo oxides are active and evolve oxygen via a NiOO - precursor. Fe incorporation not only dramatically increases the activity, but also changes the nature of the active sites., (© 2019 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.)

Photosynthesis is the model system for energy conversion. It uses CO 2 as a starting reactant to convert solar energy into chemical energy, i.e., organic molecules or biomass. The first and rate-determining step of this cycle is the immobilization and activation of CO 2 , catalyzed by RuBisCO enzyme, the most abundant protein on earth. Here, we propose a strategy to develop novel biomimetic two-dimensional (2D) nanostructures for CO 2 adsorption at room temperature by reductionist mimicking of the Mg-carboxylate RuBisCO active site. We present a method to synthesize a 2D surface-supported system based on Mg 2+ centers stabilized by a carboxylate environment and track their structural dynamics and reactivity under either CO 2 or O 2 exposure at room temperature. The CO 2 molecules adsorb temporarily on the Mg 2+ centers, producing a charge imbalance that catalyzes a phase transition into a different configuration, whereas O 2 adsorbs on the Mg 2+ center, giving rise to a distortion in the metal-organic bonds that eventually leads to the collapse of the structure. The combination of bioinspired synthesis and surface reactivity studies demonstrated here for Mg-based 2D ionic networks holds promise for the development of new catalysts that can work at room temperature., Competing Interests: The authors declare no competing financial interest.

Biological systems are able to control the assembly and positioning of proteins with nanoscale precision, as exemplified by the intricate molecular structures within cell membranes, virus capsids, and collagen matrices. Controlling the assembly of biomolecules is critical for the use of biomaterials in artificial systems such as antibacterial coatings, engineered tissue samples, and implanted medical devices. Furthermore, understanding the dynamics of protein assembly on heterogeneous templates will ultimately enable the control of protein crystallization in general. Here, we show a biomimetic, hierarchical bottom-up approach to direct the self-assembly of crystalline S-layers through nonspecific interactions with nanostructured block copolymer (BCP) thin-film templates. A comparison between physically and chemically patterned BCP substrates shows that chemical heterogeneity is required to confine the adhesion and self-assembly of S-layers to specific BCP domains. Furthermore, we show that this mechanism can be extended to direct the formation of collagen fibers along the principal direction of the underlying BCP substrate. The dynamics of protein self-assembly at the solid-liquid interface are followed using in situ high-resolution atomic force microscopy under continuous flow conditions, allowing the determination of the rate constants of the self-assembly. A pattern of alternating, chemically distinct nanoscale domains drastically increases the rate of self-assembly compared to non-patterned chemically homogeneous substrates.

By using high-speed and high-resolution Atomic Force Microscopy (AFM), it was possible to resolve within a single experiment the kinetic pathway in S-layer self-assembly at the solid-liquid interface, obtaining a model that accounts for the nucleation, growth and structural rearrangements in 2D protein self assembly across time (second to hours) and spatial scales (nm to microns).

Gross anatomy is located in a three-dimensional space. Visualizing aspects of structures in gross anatomy education should aim to provide information that best resembles their original spatial proportions. Stereoscopic three-dimensional imagery might offer possibilities to implement this aim, though some research has revealed potential impairments that may result from observing stereoscopic visualizations, such as discomfort. However, possible impairments of working memory such as decreased visual attention performance due to applying this technology in gross anatomy education have not yet been investigated. Similarly, in gross anatomy education the impact of stereoscopic imagery on learners' recognition of anatomical-spatial relationships and the impact of different presentation formats have only been investigated in a small number of studies. In this study, the performance of 171 teacher trainees working on the anatomy of hearing was examined, either with non-stereoscopic or stereoscopic imagery. Static and dynamic picture presentations were applied. Overall, benefits for stereoscopic imagery on estimating anatomical-spatial relations were found. The performance on a visual attention test indicates that the impact of stereoscopic visualizations on the human cognitive system varies more from person to person compared to non-stereoscopic visualizations. In addition, combinations of temporarily moving pictures and stereoscopic imagery lead to decreased visual attention performance compared to combinations of moving pictures and non-stereoscopic imagery. Anat Sci Educ 11: 15-24. © 2017 American Association of Anatomists., (© 2017 American Association of Anatomists.)

The van der Waals (vdW) interactions of n-alkanethiols (ATs) adsorbed on planar Au(111) and Au(100) surfaces and curved Au nanoparticles of different diameters are reported. By means of electrochemical measurements and molecular dynamic calculations, the increase in the average geometrical curvature of the surface influences the global interactions, that is, decreasing vdW interactions between neighboring molecules. Small NPs do not present the same electrochemical behavior as planar surfaces. The transition between nanoparticle to flat surface electrochemical response is estimated to occur at a circa 13-20 nm diameter range., (© 2017 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.)

The effect of the Au crystalline plane on the adsorption of different thiols and selenols is studied via reductive desorption (RD) and X-ray photoelectron spectroscopy (XPS) measurements. Self-assembled monolayers (SAMs) using aliphatic (ATs) and aromatic thiols (ArTs) on both Au(111) and Au(100) were prepared. The electrochemical stability of these SAMs on both surfaces is evaluated by comparing the position of the RD peaks. The longer the AT chain the more stable the SAM on Au(100) when compared to Au(111). By means of XPS measurements, we determine that the binding energy (BE) of the S 2p signal corresponding to the S atoms at the thiol/Au interface, commonly assigned at 162.0 eV, shifts 0.2 eV from Au(111) to Au(100) for SAMs prepared using thiols with the C* (C atom bonded to S) in sp 3 hybridization, such as ATs. However, when the thiol presents the C* with an sp 2 hybridization, such as in the case of ArTs, the BE remains at 162.0 eV regardless of the surface plane. Selenol-based SAMs were characterized comparatively on both Au(100) and Au(111). Our results show that selenol SAMs become even more electrochemically stable on Au(100) with respect to Au(111) than the analogue sulfur-based SAM. According to our results, we suggest that the electronic distribution around the Au-S/Se bond could be responsible for the different structural arrangements reported in the literature (gold adatoms, etc.), which should be dependent on the crystalline face (Au(hkl)-S) and the chemical nature of the environment of the adsorbates (sp 3 -C* vs sp 2 -C* and Au-SR vs Au-SeR).

The chiral expression of a molecule on a surface is driven from a random solid solution on Cu(100) to a racemic crystal on a Sn/Cu(100) alloy. Density functional theory simulations reveal how the growth of the racemate is influenced by the underlying surface.

A convergent synthesis of racemic 5-amino[6]hexahelicene is described. Cross-coupling reactions are used to assemble a pentacyclic framework, and a metal-catalyzed ring-closure comprises the final step. The enantiomers were separated by means of chromatography and the absolute configurations were assigned by comparison of the CD spectra with hexahelicene. The t1/2  value for racemization at 210 °C was approximately 1 hour. Scanning tunneling microscopy (STM) measurements were carried out on enantiopure and racemic samples of aminohelicene on Au(111) under ultrahigh vacuum (UHV) conditions., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Dynamically switchable supramolecular systems offer exciting possibilities in building smart surfaces, the structure and thus the function of which can be controlled by using external stimuli. Here we demonstrate an elegant approach where the guest binding ability of a supramolecular surface can be controlled by inducing structural transitions in it. A physisorbed self-assembled network of a simple hydrogen bonding building block is used as a switching platform. We illustrate that the reversible transition between porous and nonporous networks can be accomplished using an electric field or applying a thermal stimulus. These transitions are used to achieve controlled guest release or capture at the solution-solid interface. The electric field and the temperature-mediated methods of guest release are operative at different length scales. While the former triggers the transition and thus guest release at the nanometer scale, the latter is effective over a much larger scale. The flexibility associated with physisorbed self-assembled networks renders this approach an attractive alternative to conventional switchable systems.

Recently, several research groups have reported the growth of germanene, a new member of the graphene family. Germanene is in many aspects very similar to graphene, but in contrast to the planar graphene lattice, the germanene honeycomb lattice is buckled and composed of two vertically displaced sub-lattices. Density functional theory calculations have revealed that free-standing germanene is a 2D Dirac fermion system, i.e. the electrons behave as massless relativistic particles that are described by the Dirac equation, which is the relativistic variant of the Schrödinger equation. Germanene is a very appealing 2D material. The spin-orbit gap in germanene (~24 meV) is much larger than in graphene (<0.05 meV), which makes germanene the ideal candidate to exhibit the quantum spin Hall effect at experimentally accessible temperatures. Additionally, the germanene lattice offers the possibility to open a band gap via for instance an externally applied electrical field, adsorption of foreign atoms or coupling with a substrate. This opening of the band gap paves the way to the realization of germanene based field-effect devices. In this topical review we will (1) address the various methods to synthesize germanene (2) provide a brief overview of the key results that have been obtained by density functional theory calculations and (3) discuss the potential of germanene for future applications as well for fundamentally oriented studies.

Metal-organic supramolecular chemistry on surfaces has matured to a point where its underlying growth mechanisms are well understood and structures of defined coordination environments of metal atoms can be synthesized in a controlled and reproducible procedure. With surface-confined molecular self-assembly, scientists have a tool box at hand which can be used to prepare structures with desired properties, as for example a defined oxidation number and spin state of the transition metal atoms within the organic matrix. From a structural point of view, these coordination sites in the supramolecular structure resemble the catalytically active sites of metallo-enzymes, both characterized by metal centers coordinated to organic ligands. Several chemical reactions take place at these embedded metal ions in enzymes and the question arises whether these reactions also take place using metal-organic networks as catalysts. Mimicking the active site of metal atoms and organic ligands of enzymes in artificial systems is the key to understanding the selectivity and efficiency of enzymatic reactions. Their catalytic activity depends on various parameters including the charge and spin configuration in the metal ion, but also on the organic environment, which can stabilize intermediate reaction products, inhibits catalytic deactivation, and serves mostly as a transport channel for the reactants and products and therefore ensures the selectivity of the enzyme. Charge and spin on the transition metal in enzymes depend on the one hand on the specific metal element, and on the other hand on its organic coordination environment. These two parameters can carefully be adjusted in surface confined metal-organic networks, which can be synthesized by virtue of combinatorial mixing of building synthons. Different organic ligands with varying functional groups can be combined with several transition metals and spontaneously assemble into ordered networks. The catalytically active metal centers are adequately separated by the linking molecules and constitute promising candiates for heterogeneous catalysts. Recent advances in synthesis, characterization, and catalytic performance of metal-organic networks are highlighted in this Account. Experimental results like structure determination of the networks, charge and spin distribution in the metal centers, and catalytic mechanisms for electrochemical reactions are presented. In particular, we describe the activity of two networks for the oxygen reduction reaction in a combined scanning tunneling microscopy and electrochemical study. The similarities and differences of the networks compared to metallo-enzymes will be discussed, such as the metal surface that operates as a geometric template and concomitantly functions as an electron reservoir, and how this leads to a new class of bioinspired catalysts. The possibility to create functional two-dimensional coordination complexes at surfaces taking inspiration from nature opens up a new route for the design of potent nanocatalyst materials for energy conversion.

We use the electric field in a scanning tunneling microscope to manipulate the transition between open and close packed 2D supramolecular networks of neutral molecules in nonpolar media. We found that while the magnitude of the applied field is not decisive, it is the sign of the polarization that needs to be maintained to select one particular polymorph. Moreover, the switching is independent of the solvent used and fully reversible. We propose that the orientation of the surface dipole determined by the electric field might favor different conformation-depended charge transfer mechanisms of the adsorbates to the surface, inducing open (closed) structures for negative (positive) potentials. Our results show the use of local fields to select the polymorphic outcome of supramolecular assemblies at the solid/liquid interface. The effect has potential to locally control the capture and release of analytes in host-guest systems and the 2D morphology in multicomponent layers.

A combination of Scanning Tunnelling Microscopy and Density Functional Theory simulations highlights the role of van der Waals interactions in the self-assembly of an aminohelicene on Cu(100) and Au(111).

The controlled crystallization of enantiomers of an organic compound (a cyclic phosphoric acid derivative) on templated micro-patterned functionalised surfaces is demonstrated. Areas where a complementary chiral thiol has been located were effective heterogeneous nucleation centres when a solution of the compound is evaporated slowly. Various organic solvents were employed, which present a challenge with respect to other examples when water is used. The solvent and the crystallization method have an important influence on the crystal growth of these compounds. When chloroform was employed, well-defined crystals grow away from the surface, whereas crystals grow in the plane from solutions in isopropanol. In both cases, nucleation is confined to the polar patterned regions of the surface, and for isopropanol growth is largely limited within the pattern, which shows the importance of surface chemistry for nucleation and growth. The apparent dependence on the enantiomer used in the latter case could imply stereo-differentiation as a result of short-range interactions (the templating monolayer is disordered, even at the nanometre scale). The size of the pattern of chiral monolayer also determines the outcome of the crystallization; 5 μm dots are most effective. Despite the low surface tension of the samples (relative to the high surface tension of water), differential solvation of the polar and hydrophobic layers of the solvents allows crystallization in the polar regions of the monolayer, therefore the polarity of the regions in which heterogeneous nucleation takes place is indeed very important. Despite the complex nature of the crystallization process, these results are an important step towards to the use of patterned surfaces for heterogeneous selective nucleation of enantiomers., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A new chiral nonracemic thiol derived from a popular acidic resolving agent that incorporates a cyclic disubstituted phosphate group (phencyphos) has been prepared in enantiomerically pure form. The stereochemistry and absolute configuration were established by performing a single-crystal X-ray structural analysis of a synthetic intermediate. The thiol compound was used for the preparation of self-assembled monolayers (SAMs) on both monocrystalline and polycrystalline metallic gold, which have very different surface roughness. The monolayers were used to promote the nucleation and growth of crystals from nonaqueous solutions of an organic molecule (the parent phencyphos) of similar structure to the compound present in the monolayer. The template layers influence the nucleation and growth of the phencyphos crystals despite the lack of two-dimensional order in the surfaces. Heterogeneous nucleation of phencyphos takes place upon evaporation of either CHCl(3) or isopropanol solutions of the compound on the SAM surfaces, where the evaporation rate merely influences the size and homogeneity of the crystals. The roughness of the surface also plays an important role; the polycrystalline gold produces more homogeneous samples because of the greater number of nucleation sites. Clear evidence for nucleation and growth on the surfaces is shown by scanning electron microscopy. The variation in crystal form achieved by using different surfaces and solvents suggests that the layers are applicable for the preparation of organic crystals from organic solutions., (Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The possibility of modifying the intermolecular interactions of absorbed benzene-carboxylic acids from coordination to hydrogen bonding by changing their surface coverage is demonstrated through a combination of scanning tunnelling microscopy, X-ray photoemission spectroscopy and density functional theory calculations., (This journal is © The Royal Society of Chemistry 2012)

Magnetic atoms at surfaces are a rich model system for solid-state magnetic bits exhibiting either classical or quantum behaviour. Individual atoms, however, are difficult to arrange in regular patterns. Moreover, their magnetic properties are dominated by interaction with the substrate, which, as in the case of Kondo systems, often leads to a decrease or quench of their local magnetic moment. Here, we show that the supramolecular assembly of Fe and 1,4-benzenedicarboxylic acid molecules on a Cu surface results in ordered arrays of high-spin mononuclear Fe centres on a 1.5 nm square grid. Lateral coordination with the molecular ligands yields unsaturated yet stable coordination bonds, which enable chemical modification of the electronic and magnetic properties of the Fe atoms independently from the substrate. The easy magnetization direction of the Fe centres can be switched by oxygen adsorption, thus opening a way to control the magnetic anisotropy in supramolecular layers akin to that used in metallic thin films.

The primary prevention of childhood obesity requires combined efforts by stakeholders at various societal levels, based on the knowledge from multiple disciplines. The goal of the present study was therefore to analyze current preventive approaches and delineate implications for future prevention research and practice by integrating knowledge from genetics, law, economics, psychology, and social ethics. Inconclusive evidence on the etiology of obesity, a complex, multifactorial condition, likely complicates prevention, leading to a lack of specificity regarding target groups, focus, and techniques. It is recommended to increase the specificity of prevention by explicitly considering risk factor evidence, including evidence on genetic factors. Because the institutional and legal framework of primary obesity prevention in children is insufficient in many countries, considering the risk factors for childhood obesity is also crucial for establishing a basis for legal regulations. Companies from sectors concerned with food intake and physical activity may be involved in preventive action, e.g., for initiating self-defeating sanctions. Long-term behavior change may be enhanced through the systematic application of behavior modification techniques within primary prevention programs. Overall, an interdisciplinary perspective furthers understanding of the complexity of this condition and can inform public health strategies on the primary prevention of childhood obesity., (Copyright 2008 S. Karger AG, Basel.)

We report on the induced ordering of dispersed chiral diphenylalanine (Phe-Phe) chains grown on the anisotropic Cu(110) and isotropic Cu(100) surfaces. Scanning tunneling microscopy (STM) data reveal that 2D extended hybrid molecular motifs can be fabricated by utilizing terephthalic acid (TPA) molecules as linkers. These act as a molecular "glue" to bridge the isolated Phe-Phe chains without altering the global chirality of the final structures. Our results demonstrate the applicability and effectiveness of this 2D analogue of the 3D cocrystallization approach.

The adsorption of trimesic acid (TMA) on Cu(110) has been studied in the temperature range between 130 and 550 K and for coverages up to one monolayer. We combine scanning tunneling microscopy (STM), low-energy electron diffraction (LEED), reflection absorption infrared spectroscopy (RAIRS), X-ray photoemission spectroscopy (XPS), and density functional theory (DFT) calculations to produce a detailed adsorption phase diagram for the TMA/Cu(110) system as a function of the molecular coverage and the substrate temperature. We identify a quite complex set of adsorption phases, which are determined by the interplay between the extent of deprotonation, the intermolecular bonding, and the overall energy minimization. For temperatures up to 280 K, TMA molecules are only partly deprotonated and form hydrogen-bonded structures, which locally exhibit organizational chirality. Above this threshold, the molecules deprotonate completely and form supramolecular metal-organic structures with Cu substrate adatoms. These structures exist in the form of single and double coordination chains, with the molecular coverage driving distinct phase transitions.