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Reaction of the pincer-type ligand L3supported complex [L3PbBr][BArF24] (1) with Li[(C(═N2)TMS)] furnishes [L3Pb(C(═N2)TMS)][BArF24] (2). Diazo-compound 2eliminates dinitrogen upon irradiation affording formal plumba-alkyne 3, which persists in cold fluoroarene solutions. Variable temperature UV/Vis and NMR spectroscopies in combination with quantum-chemical calculations identify 3as a metal-substituted triplet carbene. In-crystallo irradiation of [L3Pb(C(═N2)TMS)(tol)][BArF24] (2·tol) provides a snapshot of intermolecular C–H bond insertion with toluene (4).

The diiron(II) complex, [(OCO)Fe(MeCN)]2(1, MeCN = acetonitrile), supported by the bis-phenolate carbene pincer ligand, 1,3-bis(3,5-di-tert-butyl-2-hydroxyphenyl)benzimidazolin-2-ylidene (OCO), was synthesized and characterized by single-crystal X-ray diffraction, 1H nuclear magnetic resonance, infrared (IR) vibrational, ultraviolet/visible/near-infrared (UV/vis/NIR) electronic absorption, 57Fe Mössbauer, X-band electron paramagnetic resonance (EPR) and SQUID magnetization measurements. Complex 1activates dioxygen to yield the diferric, μ-oxo-bridged complex [(OCO)Fe(py)(μ-O)Fe(O(C═O)O)(py)] (2) that was isolated and fully characterized. In 2, one of the iron–carbene bonds was oxidized to give a urea motif, resulting in an O(CNHC═O)O binding site, while the other Fe(OCO) unit remained unchanged. When the reaction is performed at −80 °C, an intensively colored, purple intermediate is observed (INT, λmax= 570 nm; ε = 5600 mol L–1cm–1). INTacts as a sluggish oxidant, reacting only with easily oxidizable substrates, such as PPh3or 2-phenylpropionic aldehyde (2-PPA). The identity of INTcan be best described as a dinuclear complex containing a closed diamond core motif [(OCO)FeIV(μ-O)2FeIV(OCO)]. This proposal is based on extensive spectroscopic [UV/vis/NIR electronic absorption, 57Fe Mössbauer, X-band EPR, resonance Raman (rRaman), X-ray absorption, and nuclear resonance vibrational (NRVS)] and computational studies. The conversion of the diiron(II) complex 1to the oxo diiron(IV) intermediate INTis reminiscent of the O2activation process in soluble methane monooxygenases (sMMO). Most importantly, the low reactivity of INTsupports the consensus that the [FeIV(μ-O)2FeIV] diamond core in sMMO is kinetically inert and needs to open up to terminal FeIV═O cores to react with the strong C–H bonds of methane.

Dimensionality reduction is often used to project time series data from multidimensional to two-dimensional space to generate visual representations of the temporal evolution. In this context, we address the problem of multidimensional time series visualization by presenting a new method to show and handle projection errors introduced by dimensionality reduction techniques on multidimensional temporal data. For visualization, subsequent time instances are rendered as dots that are connected by lines or curves to indicate the temporal dependencies. However, inevitable projection artifacts may lead to poor visualization quality and misinterpretation of the temporal information. Wrongly projected data points, inaccurate variations in the distances between projected time instances, and intersections of connecting lines could lead to wrong assumptions about the original data. We adapt local and global quality metrics to measure the visual quality along the projected time series, and we introduce a model to assess the projection error at intersecting lines. These serve as a basis for our new uncertainty visualization techniques that use different visual encodings and interactions to indicate, communicate, and work with the visualization uncertainty from projection errors and artifacts along the timeline of data points, their connections, and intersections. Our approach is agnostic to the projection method and works for linear and non-linear dimensionality reduction methods alike.

Molecular solar thermal energy storage (MOST) systems are rapidly becoming a feasible alternative to energy storage and net-zero carbon emission heating. MOST systems involve a single photoisomerization pair that incorporates light absorption, storage, and heat release processes in one recurring cycle. Despite significant recent advancements in the field, the catalytic back-reaction from MOST systems remains relatively unexplored. A wide range of applications is possible, contingent on the energy densities of the specific photoisomers. Here, we report platinum-, copper-, and nickel-based heterogeneous catalysts screened in batch conditions for the back-conversion reaction on the cyano-3-(4-methoxyphenyl)-norbornadiene/quadricyclane pair. Catalyst reactivities are investigated using structural characterization, imaging techniques, and spectroscopic analysis. Finally, the thermal stability is also explored for our best-performing catalysts.

We construct an approximate Riemann solver for scalar advection–diffusion equations with piecewise polynomial initial data. The objective is to handle advection and diffusion simultaneously to reduce the inherent numerical diffusion produced by the usual advection flux calculations. The approximate solution is based on the weak formulation of the Riemann problem and is solved within a space–time discontinuous Galerkin approach with two subregions. The novel generalized Riemann solver produces piecewise polynomial solutions of the Riemann problem. In conjunction with a recovery polynomial, the Riemann solver is then applied to define the numerical flux within a finite volume method. Numerical results for a piecewise linear and a piecewise parabolic approximation are shown. These results indicate a reduction in numerical dissipation compared with the conventional separated flux calculation of advection and diffusion. Also, it is shown that using the proposed solver only in the vicinity of discontinuities gives way to an accurate and efficient finite volume scheme.

Complexes of iron in high oxidation states are captivating research subjects due to their pivotal role as active intermediates in numerous catalytic processes. Structural and spectroscopic studies of well-defined model complexes often provide evidence of these intermediates. In addition to the fundamental molecular and electronic structure insights gained by these complexes, their reactivity also affects our understanding of catalytic reaction mechanisms for small molecule and bond-activation chemistry. Here, we report the synthesis, structural and spectroscopic characterization of a stable, octahedral Fe(VI) nitrido complex and an authenticated, unique Fe(VII) species, prepared by one-electron oxidation. The super-oxidized Fe(VII) nitride rearranges to an Fe(V) imide through an intramolecular amination mechanism and ligand exchange, which is characterized spectroscopically and computationally. This enables combined reactivity and stability studies on a single molecular system of a rare high-valent complex redox pair. Quantum chemical calculations complement the spectroscopic parameters and provide evidence for a diamagnetic (S= 0) d2Fe(VI) and a genuine S= 1/2, d1Fe(VII) configuration of these super-oxidized nitrido complexes.

Zusammenfassung: Literaturrecherchen und eigene Erfahrungen bestätigen die Bedeutung von Kombinationen im Bereich der stationären und der ambulanten Psychotherapie. Im stationären Bereich stellen Kombinationen von Verfahren wie Einzeltherapie, Gruppentherapie, kreative Verfahren und Sport einen wesentlichen Teil der Behandlung dar. Im ambulanten Bereich sind solche Kombinationen untersagt; einzelne speziell geregelte Ausnahmen bestätigen die berufspolitisch gewollte Separierung. Noch seltener wird die unvermeidliche sequenzielle Kombination von Settings, d. h. die Übergänge von stationärer, tagesklinischer und ambulanter Psychotherapie, thematisiert. Bei der Durchführung von Therapien müssen eventuell gleichzeitig stattfindende Therapien sowie die bisherigen Therapien und deren Effekte auf die Patienten berücksichtigt werden. Zu diesem versorgungspolitisch wichtigen Thema liegen fast keine empirischen Daten vor, sieht man von der Kombination mit Psychopharmaka ab.

The chemistry of carbon is governed by the octet rule, which refers to its tendency to have eight electrons in its valence shell. However, a few exceptions do exist, for example, the trityl radical (Ph3C∙) (ref. 1) and carbocation (Ph3C+) (ref. 2) with seven and six valence electrons, respectively, and carbenes (R2C:)—two-coordinate octet-defying species with formally six valence electrons3. Carbenes are now powerful tools in chemistry, and have even found applications in material and medicinal sciences4. Can we undress the carbene further by removing its non-bonding electrons? Here we describe the synthesis of a crystalline doubly oxidized carbene (R2C2+), through a two-electron oxidation/oxide-ion abstraction sequence from an electron-rich carbene5. Despite a cumulenic structure and strong delocalization of the positive charges, the dicoordinate carbon centre maintains significant electrophilicity, and possesses two accessible vacant orbitals. A two-electron reduction/deprotonation sequence regenerates the parent carbene, fully consistent with its description as a doubly oxidized carbene. This work demonstrates that the use of bulky strong electron-donor substituents can simultaneously impart electronic stabilization and steric protection to both vacant orbitals on the central carbon atom, paving the way for the isolation of a variety of doubly oxidized carbenes.

Abstract: Background: Major abdominal surgery is associated with early postoperative gastrointestinal dysfunction, which may lead to abdominal distention and vomiting, requiring nasogastric (NGT) tube insertion. This study aimed to compare the rates of early postoperative NGT insertion after open and laparoscopic colorectal surgery. Methods: A retrospective chart review was performed for patients who underwent colorectal surgery with removal of the NGT at completion of surgery. Patients who required reinsertion of the NGT in the early postoperative course were identified. The reinsertion rate for patients who underwent laparoscopic surgery was compared with that for the open group. Results: There were 103 patients in the open group and 227 in the laparoscopic group. In the laparoscopic group, 42 patients underwent conversion to open surgery. Reinsertion of the NGT was required for 18.4% of the patients in the open group, compared with 8.6% of the patients for whom the procedure was completed laparoscopically (p = 0.02). Conversion to open surgery resulted in a reinsertion rate of 17%. Conclusion: Laparoscopic colorectal surgery is associated with decreased postoperative gastrointestinal dysfunction, resulting in a significantly lower NGT reinsertion rate.

ABSTRACTThis study engaged in ethnographic observation and qualitative interviewing research practices to examine an educational program involving self-identified LGBTQ individuals who participate on classroom panel discussions and question/answer sessions about their coming out experiences. By observing ten LGBTQ discussion panels and conducting 35 interviews with panelists and student audience members, we explored the classroom as a space capable of allowing for nuanced understanding of gender and sexual minoritized experiences. Our observations sensitized us to the LGBTQ panelists’ stories and student audience members’ insights. Thematic analysis of fieldnotes and interview transcripts led to the emergence of three themes: creating conditions for engagement, establishing accountability, and witnessing stories of difference. Implications for future research are also offered.

Palladium complexes with one N-heterocyclic carbene (NHC) and a pyridine ancillary ligand are powerful cross-coupling precatalysts. Herein, we report such complexes with a cyclic (alkyl)(amino)carbene (CAAC) ligand replacing the NHC. We find that the alleged reduced form, (CAAC)Pd(py), disproportionates to the (CAAC)2Pd0complex and palladium nanoparticles. This notwithstanding, they are potent catalysts in the Buchwald–Hartwig amination with aryl chlorides under mild conditions (60 °C). In the presence of dioxygen, these complexes catalyze the formation of diazenes from anilines. The catalytic activities of the NHC- and CAAC-supported palladium(0) and palladium(II) complexes are similar in the cross-coupling reaction, yet the CAAC complexes are superior for diazene formation.

The synthesis, characterization, and reactivity of a series of cobalt terminal imido complexes supported by an N-anchored tripodal tris(carbene) chelate is described, including a Co-supported singlet nitrene. Reaction of the CoIprecursor [(TIMMNmes)CoI](PF6) (TIMMNmes= tris-[2-(3-mesityl-imidazolin-2-ylidene)-methyl]amine) with p-methoxyphenyl azide yields a CoIIIimide [(TIMMNmes)CoIII(NAnisole)](PF6) (1). Treatment of 1with 1 equiv of [FeCp2](PF6) at −35 °C affords a formal CoIVimido complex [(TIMMNmes)Co(NAnisole)](PF6)2(2), which features a bent Co–N(imido)–C(Anisole) linkage. Subsequent one-electron oxidation of 2with 1 equiv of AgPF6provides access to the tricationic cobalt imido complex [(TIMMNmes)Co(NAnisole)](PF6)3(3). All complexes were fully characterized, including single-crystal X-ray diffraction (SC-XRD) analyses, infrared (IR) vibrational, ultraviolet/visible (UV/vis) electronic absorption, multinuclear NMR, X-band electron paramagnetic resonance (EPR), electron nuclear double resonance (ENDOR), and high-energy-resolution fluorescence-detected X-ray absorption spectroscopy (HERFD XAS). Quantum chemical calculations provide additional insight into the electronic structures of all compounds. The dicationic CoIVimido complex 2exhibits a doublet ground state with considerable imidyl character as a result of covalent Co–NAnisole bonding. At room temperature, 2readily converts to a CoIIamine complex involving intramolecular C–H bond amination. Electronically, tricationic complex 3can be understood as a singlet nitrene bound to CoIIIwith significant CoIVimidyl radical character. Verifying the pronounced electrophilicity, nucleophiles such as H2O and tBuNH2add to 3─analogous to the parent free nitrene─in the paraposition of the aromatic substituent, thus, clearly corroborating singlet nitrene-type reactivity.

AI is transforming the way we live and work, with the potential to improve our lives in many ways. However, there are risks associated with AI deployments including failures of model robustness and security, explainability and interpretability, bias and fairness, and privacy and ethics. While there are international efforts to define governance standards for responsible AI, these are currently only principles‐based, leaving organizations uncertain as to how they can prepare for emerging regulations or evaluate their effectiveness. We propose the use of anticipatory thinking and a flexible model risk audit (MRA) framework to bridge this gap and enable organizations to take an advantage of the benefits of responsible AI. This approach enables organizations to characterize risk at the model level and to apply the anticipatory thinking employed by high reliability organizations to achieve responsible AI deployments.

•Cumulative recording of proliferation and differentiation in situ shows that primitive HSCs are not activated by inflammation or blood loss.

The authors present the methods and outcomes from six institutes where M-Tang repairs with early active flexion exercise are used for zone 2 digital flexor tendon repair. The authors had close to zero repair ruptures, and few digits needed tenolysis. The excellent to good results are generally between 80% and 90%. In the pandemic period, less stringent therapy supervision might have allowed some patients to move too aggressively, with repair ruptures not seen before the pandemic in one institute. In Nantong, Yixing, and Saint John, the rupture incidence is zero to 1%. In Florence and Heidelberg, the rupture incidence was 3%.

ABSTRACTUNESCO heritage policies encourage the idea that heritage should be ‘shared’ at the international scale, and invite states and the involved actors to adopt this vision. Yet, ‘sharedness’ can be understood in many different ways. This paper explores several territorial and political issues related to this notion of sharedness. A focus on the uses of a particular UNESCO tool – ‘multinational nominations’ – sheds a light on transnational cultural practices and examines forms of cooperation within communities and between states in the framework of the Convention for the Safeguarding of the Intangible Cultural Heritage (ICH). Specifically, it analyses the work of a French commission for the ICH as well as the nomination processes of three different cultural practices to the ICH lists: flamenco, falconry and alpinism. It is argued that ‘shared heritage’ is interpreted in a variety of ways, leading to contrastive appropriations and competing territorial scenarios among the various protagonists.

Rational innovation of electrocatalysts requires detailed knowledge of spatial property variations across the solid–electrolyte interface. We introduce correlative atomic force microscopy (AFM) to simultaneously probe, in situand at the nanoscale, electrical conductivity, chemical-frictional, and morphological properties of a bimetallic copper–gold system for CO2electroreduction. In air, water, and bicarbonate electrolyte, current–voltage curves reveal resistive CuOxislands in line with local current contrasts, while frictional imaging indicates qualitative variations in the hydration layer molecular ordering upon change from water to electrolyte. Nanoscale current contrast on polycrystalline Au shows resistive grain boundaries and electrocatalytically passive adlayer regions. In situconductive AFM imaging in water shows mesoscale regions of low current and reveals that reduced interfacial electric currents are accompanied by increased friction forces, thus indicating variations in the interfacial molecular ordering affected by the electrolyte composition and ionic species. These findings provide insights into how local electrochemical environments and adsorbed species affect interfacial charge transfer processes and support building in situstructure–property relationships in catalysis and energy conversion research.

As key intermediates in metal-catalyzed nitrogen-transfer chemistry, terminal imido complexes of iron have attracted significant attention for a long time. In search of versatile model compounds, the recently developed second-generation N-anchored tris-NHC chelating ligand tris-[2-(3-mesityl-imidazole-2-ylidene)-methyl]amine (TIMMNMes) was utilized to synthesize and compare two series of mid- to high-valent iron alkyl imido complexes, including a reactive Fe(V) adamantyl imido intermediate en route to an isolable Fe(V) nitrido complex. The chemistry toward the iron adamantyl imides was achieved by reacting the Fe(I) precursor [(TIMMNMes)FeI(N2)]+(1) with 1-adamantyl azide to yield the corresponding trivalent iron imide. Stepwise chemical reduction and oxidation lead to the isostructural series of low-spin [(TIMMNMes)Fe(NAd)]0,1+,2+,3+(2Ad–5Ad) in oxidation states II to V. The Fe(V) imide [(TIMMNMes)Fe(NAd)]3+(5Ad) is unstable under ambient conditions and converts to the air-stable nitride [(TIMMNMes)FeV(N)]2+(6) via N–C bond cleavage. The stability of the pentavalent imide can be increased by derivatizing the nitride [(TIMMNMes)FeIV(N)]+(7) with an ethyl group using the triethyloxonium salt Et3OPF6. This gives access to the analogous series of ethyl imides [(TIMMNMes)Fe(NEt)]0,1+,2+,3+(2Et–5Et), including the stable Fe(V) ethyl imide. Iron imido complexes exist in a manifold of different electronic structures, ultimately controlling their diverse reactivities. Accordingly, these complexes were characterized by single-crystal X-ray diffraction analyses, SQUID magnetization, and electrochemical methods, as well as 57Fe Mössbauer, IR vibrational, UV/vis electronic absorption, multinuclear NMR, X-band EPR, and X-ray absorption spectroscopy. Our studies are complemented with quantum chemical calculations, thus providing further insight into the electronic structures of all complexes.

Die Stigmatisierung von Patient:innen mit Hauterkrankungen rückte erst unlängst in den Fokus der Forschung. Dabei sind sowohl die Fremdstigmatisierung durch die Gesellschaft als auch die Selbststigmatisierung durch die Betroffenen selbst bei Hauterkrankungen weit verbreitet. Viele Studien zeigen, dass das Erleben von Stigmatisierung durch andere sowie durch die eigene Person in dieser Patient:innen-Gruppe mit psychosozialer Belastung, z. B. sozialen Ängsten, einhergeht. Dies ist häufig unabhängig von der Sichtbarkeit der Hautläsionen. Aus der Belastung der Betroffenen können sich psychische Komorbiditäten wie Depressionen oder Angststörungen entwickeln, weshalb es wichtig ist, Patient:innen im dermatologischen Setting auf das Vorliegen dieser Erkrankungen zu untersuchen. Interventionen zur Reduktion der Fremd- und Selbststigmatisierung wurden bereits entwickelt. Es sind allerdings weitere randomisierte kontrollierte Studien zur Überprüfung der Wirksamkeit solcher Maßnahmen erforderlich.

The discovery of genetic loci associated with complex diseases has outpaced the elucidation of mechanisms of disease pathogenesis. Here we conducted a genome-wide association study (GWAS) for coronary artery disease (CAD) comprising 181,522 cases among 1,165,690 participants of predominantly European ancestry. We detected 241 associations, including 30 new loci. Cross-ancestry meta-analysis with a Japanese GWAS yielded 38 additional new loci. We prioritized likely causal variants using functionally informed fine-mapping, yielding 42 associations with less than five variants in the 95% credible set. Similarity-based clustering suggested roles for early developmental processes, cell cycle signaling and vascular cell migration and proliferation in the pathogenesis of CAD. We prioritized 220 candidate causal genes, combining eight complementary approaches, including 123 supported by three or more approaches. Using CRISPR–Cas9, we experimentally validated the effect of an enhancer in MYO9B, which appears to mediate CAD risk by regulating vascular cell motility. Our analysis identifies and systematically characterizes >250 risk loci for CAD to inform experimental interrogation of putative causal mechanisms for CAD.

Atrial septal defects (ASDs) encounter for 10–15% of congenital heart defects [1].

Chlorhexidine skin antisepsis is frequently recommended for most surgical procedures; however, it is unclear if these recommendations should apply to surgery involving traumatic contaminated wounds where povidone-iodine has previously been preferred. We aimed to compare the effect of aqueous 10% povidone-iodine versus aqueous 4% chlorhexidine gluconate on the risk of surgical site infection in patients who required surgery for an open fracture.

The aim of this study was to adapt the CROPGRO model to simulate growth and development processes of Amaranthusspp. under central European conditions. In 2017 and 2018, two field experiments with two amaranth cultivars (grain type, A. hypochondriacusL. Neuer Typ [NT]; fodder type, A. caudatusL. K63 [K63]) were conducted in southern Germany. Based on experimental and literature data, parameter coefficients that drive physiological processes at species, cultivar, and ecotype levels were calibrated to predict the time series experimental observations of various growth and development traits. Statistical evaluation of the model adaptation was performed using root mean square error (RMSE, in variable units, 0 equals perfect fit) and the Willmott agreement index (d‐Stat., range from 0 to 1, 1 equals perfect fit). For NT and K63, respectively, the model adaptation led to accurate predictions of canopy height (RMSE, 0.07 and 0.24 m; d‐Stat.,0.98 and 0.92), panicle weight (RMSE, 2,034 and 1,153 kg ha–1; d‐Stat., 0.92 and 0.94), panicle harvest index (RMSE, 0.05 and 0.06; d‐Stat., 0.99 and 0.96), leaf N concentration (RMSE, 0.38 and 0.40%; d‐Stat., 0.94 and 0.92) and aboveground biomass (RMSE, 2,948 and 2,572 kg ha–1; d‐Stat., 0.88 and 0.91). In summary, the CROPGRO model was successfully adapted for Amaranthusspp. The adapted model can be further improved as it is made available for evaluation in different locations and environments including limited soil N supply. A physiological process‐based mechanistic model was adapted to Amaranthusssp. for the first time.Panicle weight and harvest index, leaf N concentration, and aboveground biomass were accurately predicted.Amaranth showed a low requirement for N and considerable drought tolerance.