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Two-photon photopolymerization delivers prints without support structures and minimizes layering artifacts in a broad range of materials. This volumetric printing approach scans a focused light source throughout the entire volume of a resin vat and takes advantage of the quadratic power dependence of two photon absorption to produce photopolymerization exclusively at the focal point. While this approach has advantages, the widespread adoption of two photon photopolymerization is hindered by the need for expensive ultrafast lasers and extremely slow print speeds. Here we present an analogous quadratic process, triplet-triplet-annihilation-driven 3D printing, that enables volumetric printing at a focal point driven by

Sheared peridotites from the Kaapvaal craton may be broadly divided into two types: (1) high T and refertilized and (2) low T and highly depleted, which equilibrated at conditions lying either above or along the Kaapvaal craton conductive geotherm, respectively. Here, we have studied 14 low-T sheared peridotites from Kimberley entrained by several Late Cretaceous (90 Ma) kimberlites in order to constrain the nature and timing of the deformation. The sample suite comprises nine garnet peridotites (GPs) with various amounts of clinopyroxene ± isolated spinel, three garnet-free phlogopite peridotites (PPs) with minor amounts of spinel, one garnet–spinel peridotite (GSP) and one dunite. The peridotites have intense deformation textures, ranging from porphyroclastic to fluidal mosaic. Olivine and orthopyroxene compositions (Mg# = 91–94) indicate varying degrees of depletion, similar to coarse-grained peridotites from the same localities. Pre-deformation conditions of the GPs are preserved in the cores of large (>100 μm–mm diameter) porphyroclasts and give a range in temperature of 930–1000°C at pressures of 4.0 ± 0.4 GPa. The GSP was equilibrated at 840°C and 3.1 GPa. Projected onto a 40-mW/m2 geothermal gradient, the PP samples yield temperatures of 850–870°C at 3.3–3.4 GPa. Trace element measurements by laser ablation inductively coupled plasma mass spectrometry and electron microprobe indicate that the ‘cold’ sheared peridotites were influenced by several metasomatic events, ranging from ‘old’ pre-deformation metasomatism to interactions shortly before or during deformation. The old pre-deformation metasomatism is recorded in garnet, clinopyroxene and orthopyroxene porphyroclasts and implies interactions with phlogopite–ilmenite–clinopyroxene- or muscovite–amphibole–rutile–ilmenite–diopside-related metasomatic agents, which also led to crystallization of phlogopite in the garnet-free peridotites. A ‘young’ metasomatic event caused an enrichment in Fe, Ti, Ca and Y (+heavy rare earth elements) and is evident in zoned orthopyroxene and clinopyroxene and phlogopite, the crystallization of new clinopyroxene porphyroclasts and compositional heterogeneities in garnet. This young event marks the beginning of extensive kimberlite-related metasomatism in the late Cretaceous beneath Kimberley. The metasomatism caused the deformation (triggered by a kimberlite pulse?), resulting in the recrystallization of fine-grained, mainly olivine, neoblasts (down to

Triplet fusion upconversion (UC) allows for the generation of one high energy photon from two low energy input photons. This well-studied process has significant implications for producing high energy light beyond a material's surface. However, the deployment of UC materials has been stymied due to poor material solubility, high concentration requirements, and oxygen sensitivity, ultimately resulting in reduced light output. Toward this end, nanoencapsulation has been a popular motif to circumvent these challenges, but durability has remained elusive in organic solvents. Recently, a nanoencapsulation technique was engineered to tackle each of these challenges, whereupon an oleic acid nanodroplet containing upconversion materials was encapsulated with a silica shell. Ultimately, these nanocapsules (NCs) were durable enough to enable triplet fusion upconversion-facilitated volumetric three-dimensional (3D) printing. By encapsulating upconversion materials with silica and dispersing them in a 3D printing resin, photopatterning beyond the surface of the printing vat was made possible. Here, video protocols for the synthesis of upconversion NCs are presented for both small-scale and large-scale batches. The outlined protocols serve as a starting point for adapting this encapsulation scheme to multiple upconversion schemes for use in volumetric 3D printing applications.

Gaining chemical control over the thermodynamics and kinetics of photoexcited states is paramount to an efficient and sustainable utilization of photoactive transition metal complexes in a plethora of technologies. In contrast to energies of charge transfer states described by spatially separated orbitals, the energies of spin-flip states cannot straightforwardly be predicted as Pauli repulsion and the nephelauxetic effect play key roles. Guided by multireference quantum chemical calculations, we report a novel highly luminescent spin-flip emitter with a quantum chemically predicted blue-shifted luminescence. The spin-flip emission band of the chromium complex [Cr(bpmp)2]3+ (bpmp = 2,6-bis(2-pyridylmethyl)pyridine) shifted to higher energy from ca. 780 nm observed for known highly emissive chromium(III) complexes to 709 nm. The photoluminescence quantum yields climb to 20%, and very long excited state lifetimes in the millisecond range are achieved at room temperature in acidic D2O solution. Partial ligand deuteration increases the quantum yield to 25%. The high excited state energy of [Cr(bpmp)2]3+ and its facile reduction to [Cr(bpmp)2]2+ result in a high excited state redox potential. The ligand's methylene bridge acts as a Bronsted acid quenching the luminescence at high pH. Combined with a pH-insensitive chromium(III) emitter, ratiometric optical pH sensing is achieved with single wavelength excitation. The photophysical and ground state properties (quantum yield, lifetime, redox potential, and acid/base) of this spin-flip complex incorporating an earth-abundant metal surpass those of the classical precious metal [Ru(α-diimine)3]2+ charge transfer complexes, which are commonly employed in optical sensing and photo(redox) catalysis, underlining the bright future of these molecular ruby analogues.

The late Cretaceous climate is represented by an 8-10 °C decline of global mean temperatures that terminated global warmth of mid-Cretaceous times. Causal mechanisms of the cooling are still not well constrained and discussed in the interplay of reduced volcanic greenhouse gas emission and intensified silicate weathering as a global carbon cycle feedback. The lithium isotopic composition (δ7Li) of marine carbonates is a proxy for the chemical weathering intensity of silicate rocks, and thus provides information about the role of silicate weathering as thermostat and sink for atmospheric CO2.Here, we present the first detailed chalk-derived Late Cretaceous δ7Li record (91-66 Ma) of the boreal white chalk in Northern Germany (Lägerdorf-Kronsmoor-Hemmoor) and from sections in southern England as archive for the seawater lithium isotopic composition. In the course of this study, we will also analyze the archives of skeletal calcite from brachiopods, belemnites and rudists, which should enable us to identify systematic offsets among different calcifiers related to vital effects by the direct comparison of fossilized shells and their surrounding sediments.To handle the potential impact of clay contamination in bulk carbonates, we applied a pre-leaching and leaching procedure with 1 M ammonium acetate and 0.05 M nitric acid. The method was tested for a 1.85 Ma old sample of coccolith ooze from the Manihiki Plateau (equatorial West Pacific Ocean), which has consistent δ7Li values and shows a systematic negative 3-4 ‰ offset to modern seawater. In addition, the degree of potentially leached silicates is monitored by the analysis of E/Ca ratios, like Al/Ca.In total, our late Cretaceous lithium isotope record shows a trend of rising δ7Li values between +16 and +25 ‰. Superimposed, the curve displays a rise in the Santonian, a local maximum in the early Campanian followed by a drop to a local minimum in the late Campanian. Subsequently, the δ7Li values rise again towards elevated values in the Maastrichtian. Overall, the shape of the δ7Li curve strongly resembles the evolution of deep-sea temperatures based on benthic oxygen isotopes suggesting a close link between climate and weathering. Thereby, more positive δ7Li values correspond to cooling periods and the late Campanian lowering of δ7Li values parallels the intermittent deep-sea warming. Such a pattern points towards a strong relationship between the congruency of silicate weathering and climate on a multi-million year time scale.

Lanthanide-dependent enzymes and their biomimetic complexes have arisen as an interesting target of research in the past decade. These enzymes, specifically, pyrroloquinoline quinone (PQQ)-bearing methanol dehydrogenases, efficiently convert alcohols to the respective aldehydes. To rationally design bioinspired alcohol dehydrogenation catalysts, it is imperative to understand the species involved in catalysis. However, given the extremely flexible coordination sphere of lanthanides, it is often difficult to assess the number and nature of the active species. Here, we show how such questions can be addressed by using a combination of ion mobility spectrometry, mass spectrometry, and quantum-chemical calculations to study the test systems PQQ and lanthanide-PQQ-crown ether ligand complexes. Specifically, we determine the gas-phase structures of [PQQH

Photonen-Aufkonvertierung in hetero-oligonuklearen, Metallkomplex-Architekturen mit organischen Liganden ist ein interessantes, aber bisher selten beobachtetes Phanomen, trotz des grosen Potentials sowohl aus Sicht der Grundlagenforschung als auch aus der Anwendungsperspektive. Nun wurde ein neues photonisches Material aus molekularen Chrom(III)- und Ytterbium(III)-Komplexionen entwickelt. Dieses zeigt im Festkorper bei Raumtemperatur abhangig von der Anregungsleistungsdichte nach Anregung des 2F7/2! 2F5/2-3berganges des Ytterbiums bei ca. 980 nm eine kooperative Sensibilisierung der Chrom(III)-zentrierten 2E/2T1-Phosphoreszenz bei ca. 775 nm. Der Aufkonvertierungsprozess ist unempfindlich gegenuber Luftsauerstoff und kann in Gegenwart von Wassermolekulen im Kristallgitter beobachtet werden.

The enantiomers of carboline-based cryptates were successfully resolved by chiral HPLC. These complexes show high configurational stability under harsh conditions and their absolute configuration was determined by comparing theoretical and experimental electronic circular dichroism spectra. The enantiopure cryptates exhibit strong circularly polarized luminescence with a maximum dissymmetry factor glum = 0.25 for the f-f transition 5D0→7F1 (λ = 594 nm) under visible light excitation at λex = 400 nm.

The upconversion of near-infrared (NIR) to visible (vis) photons is of interest for display technologies and energy conversion. Although triplet-triplet annihilation (TTA) offers a mechanism for upconversion that works efficiently at low incident irradiance flux densities, current strategies for NIR-vis upconversion based on TTA have fundamental limitations. Herein, we report a strategy for NIR-vis TTA based on lanthanide-containing complexes to sensitize the upconversion. We demonstrate a β-diketonate complex of Yb3+ paired with rubrene that emits yellow (λem = 559 nm) under NIR excitation (λexc = 980 nm). This corresponds to an exceptional anti-Stokes shift of just less than 1 eV. Thus, lanthanide complexes could unlock high-performance NIR-vis upconversion, with lanthanide sensitizers overcoming the energy loss, reabsorption, and short triplet lifetime that fundamentally limit porphyrin, nanocrystals, and direct S0-T1 sensitizers.

We present the results of geochemical analysis of silver coinage issued by Rome and dated between the fourth and second century BCE, which are complemented by data of coinage issued by Carthage, the Brettii, and the Greek colony of Emporion. Each of these minting authorities represents one of the major parties involved in the struggle for hegemony in the fourth to second centuries BCE Western Mediterranean region. This study retraces how the metal supply shifts in response to the transforming power relations and how this change is related to Rome's rise to the virtually uncontested ruler of the region.

The properties as well as solid‐state structures, singlet fission, and organic field‐effect transistor (OFET) performance of three tetrafluoropentacenes (1,4,8,11: 10, 1,4,9,10: 11, 2,3,9,10: 12) are compared herein. The novel compounds 10 and 11 were synthesized in high purity from the corresponding 6,13‐etheno‐bridged precursors by reaction with dimethyl 1,2,4,5‐tetrazine‐3,6‐dicarboxylate at elevated temperatures. Although most of the molecular properties of the compounds are similar, their chemical reactivity and crystal structures differ considerably. Isomer 10 undergoes the orbital symmetry forbidden thermal [4+4] dimerization, whereas 11 and 12 are much less reactive. The isomers 11 and 12 crystallize in a herringbone motif, but 10 prefers π–π stacking. Although the energy of the first electric dipole‐allowed optical transition varies only within 370 cm−1 (0.05 eV) for the neutral compounds, this amounts to roughly 1600 cm−1 (0.20 eV) for radical cations and 1300 cm−1 (0.16 eV) for dications. Transient spectroscopy of films of 11 and 12 reveals singlet‐fission time constants (91±11, 73±3 fs, respectively) that are shorter than for pentacene (112±9 fs). OFET devices constructed from 11 and 12 show close to ideal thin‐film transistor (TFT) characteristics with electron mobilities of 2×10−3 and 6×10−2 cm2 V−1 s−1, respectively., Under the influence of fluorine: The (photo‐)physical and chemical properties of tetrafluoropentacene regioisomers are altered considerably in dependence of the substitution pattern. The variation of the fluorination degree and pattern of pentacenes provides a useful model for gaining detailed insight into forces that control crystallization and for studying the structure–property relationships of these organic semiconductors.

A 2,2'-bipyridine-N,N'-dioxide-based cryptand has been found to exhibit exceptional apparent complex stability for Ca2+ and unusually shows very high selectivity for Ca2+ over trivalent lanthanoid cations. The calcium cryptate is kinetically inert to an extent that it even withstands competition experiments with a 77-fold excess of free DOTA ligand, which is currently the chelator with the highest formation constant for calcium.

Composite peening is a process to embed ceramic particles into the surface of materials with the aim to improve the mechanical and tribological properties. These properties depend essentially on the penetration depth of the particles. In order to investigate the penetration depth achieved with composite peening, micrographs were taken and evaluated employing digital image processing. In composite peening, the blasting particles penetrate the surface of the substrate depending on the process parameters. Models from the field of solid particle erosion were applied to predict the penetration depth of the particles. These analytical models can be used to evaluate the influence of specific process parameters on the penetration depth in composite peening. Furthermore, an additional model from ballistics was implemented. A good qualitative agreement was found between the analytical approaches and the experiments regarding the penetration depth after composite peening for the given system. In the future, this will allow estimating the penetration depth for other process parameters and materials for composite peening as well as for issues related to solid particle erosion.

Metasomatized mantle wedge peridotites exhumed within high-pressure terranes of continental collision zones provide unique insights into crust-mantle interaction and attendant mass transfer, which are critical to our understanding of terrestrial element cycles. Such peridotites occur in high-grade gneisses of the Ulten Zone in the European Alps and record metasomatism by crustal fluids at 330 Ma and high-pressure conditions (2.0 GPa, 850 °C) that caused a transition from coarse-grained, garnet-bearing to fine-grained, amphibole-rich rocks. We explored the effects of crustal fluids on canonically robust Lu-Hf peridotite isotope signatures in comparison with fluid-sensitive trace elements and Nd-Li isotopes. Notably, we found that a Lu-Hf pseudo-isochron is created by a decrease in bulk-rock 176Lu/177Hf from coarse- to fine-grained peridotite that is demonstrably caused by heavy rare earth element (HREE) loss during fluid-assisted, garnet-consuming, amphibole-forming reactions accompanied by enrichment in fluid-mobile elements and the addition of unradiogenic Nd. Despite close spatial relationships, some peridotite lenses record more intense fluid activity that causes complete garnet breakdown and high field strength element (HFSE) addition along with the addition of crust-derived unradiogenic Hf, as well as distinct chromatographic light REE (LREE) fractionation. We suggest that the observed geochemical and isotopic provinciality between peridotite lenses reflects different positions relative to the crustal fluid source at depth. This interpretation is supported by Li isotopes: inferred proximal peridotites show light δ7Li due to strong kinetic Li isotope fractionation (−4.7–2.0‰) that accompanies Li enrichment, whereas distal peridotites show Li contents and δ7Li similar to those of the depleted mantle (1.0–7.2‰). Thus, Earth's mantle can acquire significant Hf-Nd-Li-isotopic heterogeneity during locally variable ingress of crustal fluids in continental subduction zones.

Correction for ‘Distinct photodynamics of κ-N and κ-C pseudoisomeric iron(ii) complexes’ by Philipp Dierks et al., Chem. Commun., 2021, 57, 6640–6643, https://doi.org/10.1039/D1CC01716K.

Photoactive metal complexes employing Earth‐abundant metal ions are a key to sustainable photophysical and photochemical applications. We exploit the effects of an inversion center and ligand non‐innocence to tune the luminescence and photochemistry of the excited state of the [CrN6] chromophore [Cr(tpe)2]3+ with close to octahedral symmetry (tpe=1,1,1‐tris(pyrid‐2‐yl)ethane). [Cr(tpe)2]3+ exhibits the longest luminescence lifetime (τ=4500 μs) reported up to date for a molecular polypyridyl chromium(III) complex together with a very high luminescence quantum yield of Φ=8.2 % at room temperature in fluid solution. Furthermore, the tpe ligands in [Cr(tpe)2]3+ are redox non‐innocent, leading to reversible reductive chemistry. The excited state redox potential and lifetime of [Cr(tpe)2]3+ surpass those of the classical photosensitizer [Ru(bpy)3]2+ (bpy=2,2′‐bipyridine) enabling energy transfer (to oxygen) and photoredox processes (with azulene and tri(n‐butyl)amine)., Super‐long luminescence lifetime (4500 μs) at room temperature, high quantum yield (8.2 %) and reversible redox chemistry in the complex [Cr(tpe)2]3+ containing an Earth‐abundant first row transition metal ion is enabled by ligand bite angle, inversion symmetry and ligand non‐innocence (tpe=1,1,1‐tris (pyrid‐2‐yl)ethane). [Cr(tpe)2]3+ is competent in light‐induced energy and electron transfer processes similar to classical noble metal ion complexes.

tRNAs from all domains of life contain modified nucleotides. However, even for the experimentally most thoroughly characterized model organism Escherichia coli not all tRNA modification enzymes are known. In particular, no enzyme has been found yet for introducing the acp3U modification at position 47 in the variable loop of eight E. coli tRNAs. Here we identify the so far functionally uncharacterized YfiP protein as the SAM-dependent 3-amino-3-carboxypropyl transferase catalyzing this modification and thereby extend the list of known tRNA modification enzymes in E. coli. Similar to the Tsr3 enzymes that introduce acp modifications at U or m1Ψ nucleotides in rRNAs this protein contains a DTW domain suggesting that acp transfer reactions to RNA nucleotides are a general function of DTW domain containing proteins. The introduction of the acp3U-47 modification in E. coli tRNAs is promoted by the presence of the m7G-46 modification as well as by growth in rich medium. However, a deletion of the enzymes responsible for the modifications at position 46 and 47 in the variable loop of E. coli tRNAs did not lead to a clearly discernible phenotype suggesting that these two modifications play only a minor role in ensuring the proper function of tRNAs in E. coli.

The TonB-dependent transport of scarcely available substrates across the outer membrane is a conserved feature in Gram-negative bacteria. The plasma membrane-embedded TonB-ExbB-ExbD accomplishes complex functions as an energy transducer by physically interacting with TonB-dependent outer membrane transporters (TBDTs). TonB mediates structural rearrangements in the substrate-loaded TBDTs that are required for substrate translocation into the periplasm. In the model heterocyst-forming cyanobacterium Anabaena sp. strain PCC 7120, four TonB-like proteins have been identified. Out of these TonB3 accomplishes the transport of ferric schizokinen, the siderophore which is secreted by Anabaena to scavenge iron. In contrast, TonB1 (SjdR) is exceptionally short and not involved in schizokinen transport. The proposed function of SjdR in peptidoglycan structuring eliminates the protein from the list of TonB proteins in Anabaena. Compared with the well-characterized properties of SjdR and TonB3, the functions of TonB2 and TonB4 are yet unknown. Here, we examined tonB2 and tonB4 mutants for siderophore transport capacities and other specific phenotypic features. Both mutants were not or only slightly affected in schizokinen transport, whereas they showed decreased nitrogenase activity in apparently normal heterocysts. Moreover, the cellular metal concentrations and pigment contents were altered in the mutants, most pronouncedly in the tonB2 mutant. This strain showed an altered susceptibility toward antibiotics and SDS and formed cell aggregates when grown in liquid culture, a phenotype associated with an elevated lipopolysaccharide (LPS) production. Thus, the TonB-like proteins in Anabaena appear to take over distinct functions, and the mutation of TonB2 strongly influences outer membrane integrity. IMPORTANCE The genomes of many organisms encode more than one TonB protein, and their number does not necessarily correlate with that of TonB-dependent outer membrane transporters. Consequently, specific as well as redundant functions of the different TonB proteins have been identified. In addition to a role in uptake of scarcely available nutrients, including iron complexes, TonB proteins are related to virulence, flagellum assembly, pilus localization, or envelope integrity, including antibiotic resistance. The knowledge about the function of TonB proteins in cyanobacteria is limited. Here, we compare the four TonB proteins of Anabaena sp. strain PCC 7120, providing evidence that their functions are in part distinct, since mutants of these proteins exhibit specific features but also show some common impairments.

Novel BN-doped compounds based on chiral, tetrasubstituted [2.2]paracyclophane and NBN-benzo[f,g]tetracene were synthesized by Sonogashira-Hagihara coupling. Conjugated ethynyl linkers allow electronic communication between the π-electron systems through-bond, whereas through-space interactions are provided by strong π-π overlap between the pairs of NBN-building blocks. Excellent optical and chiroptical properties in racemic and enantiopure conditions were measured, with molar absorption coefficients up to ϵ=2.04×10

The TonB-dependent transport of scarcely available substrates across the outer membrane is a conserved feature in Gram-negative bacteria. The plasma membrane-embedded TonB-ExbB-ExbD accomplishes complex functions as an energy transducer by physically interacting with TonB-dependent outer membrane transporters (TBDTs). TonB mediates structural rearrangements in the substrate-loaded TBDTs that are required for substrate translocation into the periplasm. In the model heterocyst-forming cyanobacterium Anabaena sp. strain PCC 7120, four TonB-like proteins have been identified. Out of these TonB3 accomplishes the transport of ferric schizokinen, the siderophore which is secreted by Anabaena to scavenge iron. In contrast, TonB1 (SjdR) is exceptionally short and not involved in schizokinen transport. The proposed function of SjdR in peptidoglycan structuring eliminates the protein from the list of TonB proteins in Anabaena. Compared with the well-characterized properties of SjdR and TonB3, the functions of TonB2 and TonB4 are yet unknown. Here, we examined tonB2 and tonB4 mutants for siderophore transport capacities and other specific phenotypic features. Both mutants were not or only slightly affected in schizokinen transport, whereas they showed decreased nitrogenase activity in apparently normal heterocysts. Moreover, the cellular metal concentrations and pigment contents were altered in the mutants, most pronouncedly in the tonB2 mutant. This strain showed an altered susceptibility toward antibiotics and SDS and formed cell aggregates when grown in liquid culture, a phenotype associated with an elevated lipopolysaccharide (LPS) production. Thus, the TonB-like proteins in Anabaena appear to take over distinct functions, and the mutation of TonB2 strongly influences outer membrane integrity. IMPORTANCE The genomes of many organisms encode more than one TonB protein, and their number does not necessarily correlate with that of TonB-dependent outer membrane transporters. Consequently, specific as well as redundant functions of the different TonB proteins have been identified. In addition to a role in uptake of scarcely available nutrients, including iron complexes, TonB proteins are related to virulence, flagellum assembly, pilus localization, or envelope integrity, including antibiotic resistance. The knowledge about the function of TonB proteins in cyanobacteria is limited. Here, we compare the four TonB proteins of Anabaena sp. strain PCC 7120, providing evidence that their functions are in part distinct, since mutants of these proteins exhibit specific features but also show some common impairments.

Halide mixing is one of the most powerful techniques to tune the optical bandgap of metal-halide perovskites. However, halide mixing has commonly been observed to result in phase segregation, which reduces excited-state transport and limits device performance. While the current emphasis lies on the development of strategies to prevent phase segregation, it remains unclear how halide mixing may affect excited-state transport even if phase purity is maintained. Here, we study exciton transport in phase pure mixed-halide 2D perovskites of (PEA)2Pb(I1-xBrx)4. Using transient photoluminescence microscopy, we show that, despite phase purity, halide mixing inhibits exciton transport. We find a significant reduction even for relatively low alloying concentrations. By performing Brownian dynamics simulations, we are able to reproduce our experimental results and attribute the decrease in diffusivity to the energetically disordered potential landscape that arises due to the intrinsic random distribution of alloying sites, This work has been supported by the Spanish Ministry of Economy and Competitiveness through the “Mari ́ a de Maeztu” Program for Units of Excellence in R&D (MDM-2014-0377). M.S. acknowledges the financial support through a Doc.Mobility Fellowship from the Swiss National Science Foundation (SNF) with grant number 187676. In addition, M.S. acknowledges the financial support of a fellowship from ”la Caixa” Foundation (ID 100010434). The fellowship code is LCF/BQ/IN17/11620040. Further, M.S. has received funding from the European Union’s Horizon 2020 research and innovation program under the Marie Skłodowska-Curie grant agreement No. 713673. F.P. acknowledges support from the Spanish Ministry for Science, Innovation, and Universities through the state program (PGC2018-097236-A-I00) and through the Ramón y Cajal program (RYC-2017-23253), as well as the Comunidad de Madrid Talent Program for Experienced Researchers (2016-T1/IND-1209). M.M., N.C., and R.D.B. acknowledge support from the Spanish Ministry of Economy, Industry, and Competitiveness through Grant FIS2017-86007-C3-1-P (AEI/FEDER, EU). D.N.C. acknowledges the support of the Rowland Fellowship at the Rowland Institute at Harvard University and the Department of Electrical Engineering at Stanford University. M.K.G. acknowledges the support of National Science Foundation Track 1 EPSCoR funding under the grant no. 1757220. D.A.K. acknowledges the support of a Rowland Foundation Postdoctoral Fellowship

Zusammenfassung: Die Diagnose der Polymyalgia rheumatica (PMR) basiert auf der typischen Klinik und den erhöhten Entzündungsparametern im Blut. Allerdings sind beide unspezifisch. Daher stellt die gute Differenzialdiagnose der Erkrankung auch heute noch eine Herausforderung für den Kliniker dar. Offensichtlich tragen die neuen 2012 formulierten Konsensus-Klassifikationskriterien von European League Against Rheumatism (EULAR) und American College of Rheumatology (ACR) zu einer verbesserten Diagnostik der PMR sowohl hinsichtlich Sensitivität (92,6 %) als auch Spezifität (91,2 %) bei. Als Standardtherapie gelten nach wie vor Glukokortikoide und alternativ auch Methotrexat und möglicherweise in Zukunft auch eine Anti-IL-6-Therapie.

Gaining chemical control over the thermodynamics and kinetics of photoexcited states is paramount to an efficient and sustainable utilization of photoactive transition metal complexes in a plethora of technologies. In contrast to energies of charge transfer states described by spatially separated orbitals, the energies of spin-flip states cannot straightforwardly be predicted as Pauli repulsion and the nephelauxetic effect play key roles. Guided by multireference quantum chemical calculations, we report a novel highly luminescent spin-flip emitter with a quantum chemically predicted blue-shifted luminescence. The spin-flip emission band of the chromium complex [Cr(bpmp)

Five luminescent tris(bipyridine)-based cryptates with the lanthanoids Eu and Nd have been prepared with a systematic increase in the number of 2,2'-bipyridine-N,N'-dioxide units and with different deuteration levels in the complexing cryptands for the europium species. Careful analysis of the radiative lifetime τrad in these systems reveals that an increase in N-oxide units around the metal centers uniformly lowers τrad by about 30-40 %. The potential involvement of nephelauxetic effects is discussed. Exchange of 30 C-D for C-H oscillators around the europium centers does not affect the radiative lifetimes but decreases non-radiative deactivation and increases the overall luminescence quantum yield in D2 O by 45 %.

Composite peening describes a modified process based on micro shot peening. This process allows the controlled penetration of ceramic particles into areas of metallic matrix materials close to the surface layer. Composite material produced by composite peening promises a high application potential in the fields of lightweight, wear-resistant and durable materials. The use of ceramic reinforcing particles is expected to significantly improve thermal stability compared to conventional surface hardening processes. In addition, composite peening offers the possibility of cost-effectively reinforcing components and can even be applied subsequently in highly stressed surface layers. The material combination selected for this study was technically pure aluminum as model and matrix material and alumina as abrasive respectively reinforcement material. The influence on the particle density and the particle gradient was achieved by varying the process parameters, such as the process temperature and the peening pressure. A maximum penetration depth of almost 30 μm could be observed at high homologous temperatures. In light and scanning electron microscopy it was observed that the ceramic particles might break on impact with the surface of the blasting material. This causes a drastic reduction of the particle size, which initially had a size of 10 μm. This reduction of particle size promises advantages, particularly with cyclic loads.

The aim of our study was to perform comparative investigation of the tissue safety of three different endoscopic lithotripter devices including a new single-probe/dual-energy lithotripter in an in vivo animal model. The Swiss LithoClast Trilogy was compared to the Storz Calcuson and the Swiss LithoClast Vario. The safety test simulated the accidental direct contact between lithotripter probes and the urothelium, which can occur when sliding off a stone or drilling through a calculus during lithotripsy. The safety test included a smallest (1.5 mm) and largest (3.3/3.4 mm) probe diameter per device. Testing was performed in nine pigs (three animals per device). The bladder tissue was exposed to direct lithotripter probe contact at maximum power for 10 s to produce visible tissue lesions. Acute tissue trauma was evaluated using a simplified scoring model describing the expected bladder wall injuries for histological examination. After 7 days, all animals were killed, necropsied and examined post mortem. For between-group comparisons regarding microscopic histopathologic features, a Chi-square test was used. A p value

The absorption and emission spectra of three Yb3+ complexes possessing D3, D2, and C2 symmetries were analyzed with the aid of ab initio calculations based on Complete Active Space (CAS) self-consistent field wave functions (CAS(13,7)). The absorption spectra present contributions from both cold and hot bands, involving thermally populated excited sublevels of the 2F7/2 manifold. The high-resolution emission spectrum of the tris-picolinate complex [Yb(DPA)3]3- recorded at 77 K presents four components, while the complexes with macrocyclic ligands show both cold and hot emission bands, resulting in more than four components for the 2F5/2 → 2F7/2 transition. The combined information provided by the absorption and emission spectra allowed to identify most of the crystal field sublevels of the 2F5/2 and 2F7/2 states. The energies of these crystal field components are well-reproduced by the ab initio calculations, with deviations typically lower than 100 cm-1. The crystal field splitting is very sensitive to subtle changes of the Yb3+ coordination environment. The magnetic anisotropy of [Yb(DPA)3]3- obtained with ab initio calculations was found to be extremely sensitive to changes in the twist angle of the upper and lower faces of the tricapped trigonal prismatic coordination polyhedron. Ab initio ligand field theory provides a straightforward chemical justification for the changes in magnetic anisotropy, which are responsible for the observed pseudocontact shifts in the NMR spectra.

Aortic valve replacement by way of a right anterior mini-thoracotomy (RAMT) has shown excellent results in terms of mortality and morbidity. The aim of the present study was to compare RAMT aortic valve replacement (AVR) with conventional full sternotomy in regards to early perioperative outcomes and mortality.This was a retrospective, observational, cohort study of prospectively collected data from patients who underwent isolated, first time AVR between January 2013 and October 2016. Fifty-three RAMT patients were matched to a control group (conventional full sternotomy) using propensity score analysis.The characteristics of the two cohorts were similar. The in-hospital mortality was 1.9% utilising the RAMT approach versus 5.7% using the sternotomy approach (p=0.34). Ventilation times were similar in both groups (7 [5-2] vs 8 [5-13] hrs; p=0.61). However, ICU length of stay was significantly longer in the RAMT group (median, 46.5 [23-59.5] vs 20 [14-23] hrs; p0.001), which translated into a significantly longer postoperative hospital length of stay for the RAMT group (median, 8 [6-12] vs 6 [5.5-9.5] days; p=0.04) compared to the sternotomy group. RAMT was associated with a trend towards a higher incidence of postoperative AF in comparison to the sternotomy group, although this was not statistically significant (41.5% vs 28.3%; p=0.17). Patients in the RAMT group had lower 4-hour chest drain output (102.5 vs 1141ml; p=0.0.07). There was no statistically significant difference in rates of non-red cell transfusions between the two groups, (17%vs28.3%; p=0.10). The occurrence of stroke, re-exploration for bleeding, red-cell transfusion and wound infection was similar in both groups.Right anterior mini-thoracotomy in patients undergoing isolated aortic valve surgery is a safe approach in select patients, although associated with longer cardiopulmonary bypass times and ICU length of stay.

The chiral spin-flip luminophore [Cr(ddpd)2]3+ can be resolved into enantiopure material by chiral HPLC. The corresponding enantiomers show very high luminescence dissymmetry factors of up to ∣glum ∣≈ 0.093 in circularly polarized luminescence (CPL) measurements for the "ruby-like" phosphorescence transition 2E/2T1 → 4A2 in the near-IR region around λ ≈ 775 nm.

In this study we have established a new method for in situ measurements of stable lithium (Li) isotope ratios at low Li concentration levels using UV-femtosecond laser ablation coupled with multiple collector inductively coupled plasma mass spectrometry (MC-ICP-MS). Highly precise in situ determination of Li isotope ratios is challenging due to low Li concentrations in most natural minerals and matrix effects typically occurring during the ablation process and in the ion source. Here we demonstrate that matrix-dependent isotope effects in the plasma can be largely suppressed by operating the plasma under cool conditions (900 W) and a laser beam which is focused ∼130 μm below the sample surface. Under such conditions, precise and accurate measurements of δ7Li with ∼2‰ (2σ) analytical uncertainty have been performed for various glass reference materials and olivine. Depending on the Li concentration of the investigated samples, detector combinations have been optimized in order to achieve the best precision. At Li concentrations ranging from 2 to 10 μg g−1 a combination of an ion counter for the determination of 6Li and a Faraday cup equipped with a 1013 Ω amplifier for 7Li has yielded the best precision. For Li concentrations > 10 μg g−1, Faraday cups equipped with a 1013 Ω amplifier for 6Li and a 1011 Ω amplifier for 7Li are recommended. Measurements applying a 1013 Ω amplifier require a tau correction due to the slower signal response of the amplifier. The accuracy of the here-established LA-MC-ICP-MS method was tested by comparing the results obtained for reference glasses that have been analyzed both in situ and with solution MC-ICP-MS (or other conventional methods, previously applied in other studies), and the results are overall in good agreement. The applicability to a zoned olivine phenocryst from the Massif Central volcanic region has been tested successfully.

In spite of intense, recent research efforts, luminescent transition metal complexes with Earth-abundant metals are still very rare owing to the small ligand field splitting of 3d transition metal complexes and the resulting non-emissive low-energy metal-centered states. Low-energy excited states decay efficiently non-radiatively, so that near-infrared emissive transition metal complexes with 3d transition metals are even more challenging. We report that the heteroleptic pseudo-octahedral d2-vanadium(iii) complex VCl3(ddpd) (ddpd = N,N′-dimethyl-N,N′-dipyridine-2-yl-pyridine-2,6-diamine) shows near-infrared singlet → triplet spin–flip phosphorescence maxima at 1102, 1219 and 1256 nm with a lifetime of 0.5 μs at room temperature. Band splitting, ligand deuteration, excitation energy and temperature effects on the excited state dynamics will be discussed on slow and fast timescales using Raman, static and time-resolved photoluminescence, step-scan FTIR and fs-UV pump-vis probe spectroscopy as well as photolysis experiments in combination with static quantum chemical calculations. These results inform future design strategies for molecular materials of Earth-abundant metal ions exhibiting spin–flip luminescence and photoinduced metal–ligand bond homolysis., Vanadium is an abundant and cheap metal but near-infrared luminescent vanadium complexes are extremely rare with largely unexplored photophysics and photochemistry. We delineate the photodynamics of VCl3(ddpd) to infer novel design strategies.

Composite peening is a novel process to introduce ceramic blasting particles into the surface of substrates. Depending on the process parameters, the penetration depth of the blasting particles can be several micrometers. In previous investigations by some of the authors, it has been found that the ceramic particles incorporated during composite peening are significantly smaller compared to 10 μm in size before peening. Herein, the microstructure after composite peening is highlighted. To investigate this microstructure, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) are performed. The subsequent X‐ray diffraction (XRD) analysis provides further evidence of a severely deformed, nanocrystalline ceramic layer consisting of fragmented blasting particles.

Two closely related FeII complexes with 2,6-bis(1-ethyl-1H-1,2,3-triazol-4yl)pyridine and 2,6-bis(1,2,3-triazol-5-ylidene)pyridine ligands are presented to gain new insights into the photophysics of bis(tridentate) iron(II) complexes. The [Fe(N^N^N)2]2+ pseudoisomer sensitizes singlet oxygen through a MC state with nanosecond lifetime after MLCT excitation, while the bis(tridentate) [Fe(C^N^C)2]2+ pseudoisomer possesses a similar 3MLCT lifetime as the tris(bidentate) [Fe(C^C)2(N^N)]2+ complexes with four mesoionic carbenes. Financial support from the Deutsche Forschungsge-meinschaft [DFG, Priority Program SPP 2102] "Light-controlled reactivity of metal complexes" (BA 4467/7-1, LO 714/11-1, KU 952/12-1, SE 1448/8-1, HE 2778/14-1) is gratefully acknowledged by M. B., O. K., S. L., M. S. and K. H. Scopus

Two-dimensional (2D) metal-halide perovskites are attractive for use in light harvesting and light emitting devices, presenting improved stability as compared to the more conventional three-dimensional perovskite phases. Significant attention has been paid to influencing the layer orientation of 2D perovskite phases, with the charge-carrier transport through the plane of the material being orders of magnitude more efficient than the interlayer transport. Importantly though, the thinnest members of the 2D perovskite family exhibit strong exciton binding energies, suggesting that interlayer energy transport mediated by dipole–dipole coupling may be relevant. We present transient microscopy measurements of the interlayer energy transport in the (PEA)2PbI4 perovskite. We find efficient interlayer exciton transport (0.06 cm2 s−1), which translates into a diffusion length that exceeds 100 nm and a sub-ps timescale for energy transfer. While still slower than the in-plane exciton transport (0.2 cm2 s−1), our results show that excitonic energy transport is considerably less anisotropic than charge-carrier transport for 2D perovskites.