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Additive Manufacturing (AM) has revolutionized the production industry by offering design freedom with shorter lead times and reduced material wastage. However, the damage tolerance (DT) of AM parts is a significant concern due to their microstructural and geometric complexities, which affect their mechanical performance. This article aims to provide a comprehensive overview of the manufacturing parameters affecting the components produced by AM specifically selective laser melting (SLM). Detailed discussions are presented on the effects of manufacturing attributes on the microstructure, defects, and mechanical characteristics of AM parts. Depending on these aspects, basic concepts are studied and critically explained specifically for AM materials. The basic criterion for damage‐tolerant component design, the criterion for fatigue and fracture properties, and the effect of the defects on fatigue life are critically presented. In addition, the effect of different types of gradation on the crack growth behavior of samples processed by SLM is also investigated in depth. There is currently a lack of a specific review study in the literature that establishes a connection between process attributes and metallographic properties, and their impact on the damage behavior of additively manufactured parts. This gap in research highlights the need for a comprehensive review to bridge this knowledge deficit and provide valuable insights for understanding the relationships between manufacturing processes, material characteristics, and the structural integrity of additively manufactured components. This review concludes by addressing the challenges and opportunities in designing and qualifying AM parts for damage tolerance. [ABSTRACT FROM AUTHOR]

The synthesis of the first terminal mono‐boryl complexes of nickel, which are not stabilized by a pincer ligand, is reported. The reaction of the nickel bis‐boryl complex cis‐[Ni(iPr2ImMe)2(Bcat)2] 1 (cat=1,2‐O2C6H4) with the small donor ligand PMe3 led to a complete ligand exchange at nickel with reductive elimination of B2cat2 and formation of the bis‐NHC adduct [B2cat2 ⋅ (iPr2ImMe)2] 3 and [Ni(PMe3)4] 2 as the metal‐containing species. Electrophilic attack of MeI on complex 1 or ligand dismutation of 1 with trans‐[Ni(iPr2ImMe)2Br2] led to loss of only one boryl ligand of 1 and afforded the nickel mono‐boryl complexes trans‐[Ni(iPr2ImMe)2(Bcat)Br] 4 a and trans‐[Ni(iPr2ImMe)2(Bcat)I] 4 b. [ABSTRACT FROM AUTHOR]

The orientation of internal metagrain boundary shows an important influence on shearing behaviors and mechanical performance of architected polycrystal lattice. This study designs four types of architected polycrystal lattices equipped with single boundary, multiple parallel boundaries, or multiple intersecting boundaries, with boundary orientations of 0°, 26.55°, 45°, 63.45°, or 90°. The compressive responses of these architected polycrystal lattices are investigated to reveal the effects of the boundary orientations. Especially the relations between the shearing deformation and the boundary orientation are clarified, and the underlying shearing mechanisms are discussed to provide a basis for predicting and explaining the energy absorbing capacity in the architected polycrystal lattice. For the architected polycrystal lattice consisting of +30° and −30° orientated metagrains with intrinsic shear bands of 60° and 75°, the 75° rather than 60° shear band is more likely to occur when the angle of the architected polycrystal boundary increases from 0° to 90°. Most importantly, the higher energy absorption prefers the shear band more horizontal and shorter, which can be realized by increasing the angle and the number of grain boundaries. This contributes to resisting catastrophic failure for lattice structures. These findings provide guidance for developing novel lattice structures with well‐controlled mechanical characteristics. [ABSTRACT FROM AUTHOR]

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The bimetallic, decanuclear Ni3Ga7‐cluster of the formula [Ni3(GaTMP)3(μ2‐GaTMP)3(μ3‐GaTMP)] (1, TMP=2,2,6,6‐tetramethylpiperidinyl) reacts reversibly with dihydrogen under the formation of a series of (poly‐)hydride clusters 2. Low‐temperature 2D NMR experiments at −80 °C show that 2 consist of a mixture of a di‐ (2Di), tetra‐ (2Tetra) and hexahydride species (2Hexa). The structures of 2Di and 2Tetra are assessed by a combination of 2D NMR spectroscopy and DFT calculations. The cooperation of both metals is essential for the high hydrogen uptake of the cluster. Polyhydrides 2 are catalytically active in the semihydrogenation of 4‐octyne to 4‐octene with good selectivity. The example is the first of its kind and conceptually relates properties of molecular, atom‐precise transition metal/main group metal clusters to the respective solid‐state phase in catalysis. [ABSTRACT FROM AUTHOR]

Two competing theories explain the other‐'race' effect (ORE) either by greater perceptual expertise to same‐'race' (SR) faces or by social categorization of other‐'race' (OR) faces at the expense of individuation. To assess expertise and categorization contributions to the ORE, a promising—yet overlooked—approach is comparing activations for different other‐'races'. We present a label‐based systematic review of neuroimaging studies reporting increased activity in response to OR faces (African, Caucasian, or Asian) when compared with the SR of participants. Hypothetically, while common activations would reflect general aspects of OR perception, 'race'‐preferential ones would represent effects of 'race'‐specific visual appearance. We find that several studies report activation of occipito‐temporal and midcingulate areas in response to faces across different other‐'races', presumably due to high demand on the visual system and category processing. Another area reported in response to all OR faces, the caudate nucleus, suggests the involvement of socio‐affective processes and behavioural regulation. Overall, our results support hybrid models—both expertise and social categorization contribute to the ORE, but they provide little evidence for reduced motivation to process OR faces. Additionally, we identify areas preferentially responding to specific OR faces, reflecting effects of visual appearance. [ABSTRACT FROM AUTHOR]

The capability to design and manufacture metal lattice structures is today one of the most promising targets of powder bed fusion technologies. Not only additively manufactured lattices offer great lightweighting possibilities but they also open the way to tailored and graded mechanical response. To best capitalize on this opportunity, research effort is first needed to assess the feasibility of reticular structures and to quantify the expected deviations from the nominal geometry, as a function of the cell topology and dimensions. Notwithstanding the inherent suitability of additive processes to complex shapes, this paper proposes a more exact definition of the technological boundaries for body‐centered cubic lattices, showing to what extent specific dimensional ratios, as well as a self‐supporting cell structure, can be favorable to minimize the deviation from the nominal reticulum in terms of dimensions, density, and presence of defects. [ABSTRACT FROM AUTHOR]

The C−F bond activation of pentafluoropyridine and 2,3,5,6‐tetrafluoropyridine at [Ni(cod)2] (cod=1,5‐cyclooctadiene) in the presence of the phosphine PPh2(Ind) (Ind=3‐methyl‐2‐indolyl) led to the formation of the nickel(II) fluorido bis(phosphine) complexes trans‐[Ni(F)(2‐C5NF4){PPh2(Ind)}2] and trans‐[Ni(F)(2‐C5HNF3){PPh2(Ind)}2]. The complexes are characterized by the presence of intramolecular hydrogen bonds between the NH group of the phosphine ligands and the fluorido ligand. Stochiometric model reactions of nickel(II) fluorido complexes with PhB(OH)2 revealed that the former can be considered as intermediates in Suzuki–Miyaura cross coupling reactions. Catalytic experiments were attempted using 10 mol‐% of trans‐[Ni(F)(2‐C5NF4){PPh2(Ind)}2] as catalyst and the activities of the PPh2(Ind) complex were compared to the ones of an analogous nickel(II) fluorido complex, bearing PPh3 instead of PPh2(Ind) as ligands. The latter exhibited a somewhat lower catalytic activity suggesting a slight influence of the H‐bonds in the outer coordination sphere. [ABSTRACT FROM AUTHOR]

An efficient pathway to a new family of fluorinated polyheteroaromatic D‐A molecules has been developed. The method is based on the Rh(III)‐catalyzed regioselective [4+2]‐annulation of N‐(pivaloyloxy)‐benzamides with 4‐ethynyl‐5,6‐difluoro‐7‐(p‐methoxyphenyl)‐2,1,3‐benzothiadiazole as a key step followed by the aromatization/Suzuki coupling sequence to furnish the target D‐A systems with modifiable acceptor block. The discovered difference in reactivity between ArB(OH)2 and ArBPin allows performing a divergent modification of BTD acceptor block by the manipulation of aryl boronic reagents in the ortho‐selective C−F activation of the fluorinated BTD moiety under Suzuki reaction conditions to furnish new D1‐π‐A‐D2 systems in good yields. Such step‐by‐step modification of the acceptor block has been achieved by Pd‐catalyzed C−F bond activation under isoquinoline ring assistance for the first time. [ABSTRACT FROM AUTHOR]

A series of five new homoleptic, linear nickel d9‐complexes of the type [NiI(NHC)2]+ is reported. Starting from the literature known Ni(0) complexes [Ni(Mes2Im)2] 1, [Ni(Mes2ImH2)2] 2, [Ni(Dipp2Im)2] 3, [Ni(Dipp2ImH2)2] 4 and [Ni(cAACMe)2] 5 (Mes2Im=1,3‐bis(2,4,6‐trimethylphenyl)‐imidazolin‐2‐ylidene, Mes2ImH2=1,3‐bis(2,4,6‐trimethylphenyl)‐imidazolidin‐2‐ylidene, Dipp2Im=1,3‐bis(2,6‐diisopropylphenyl)‐imidazolin‐2‐ylidene, Dipp2ImH2=1,3‐bis(2,6‐diisopropylphenyl)‐imidazolidin‐2‐ylidene, cAACMe=1‐(2,6‐diisopropylphenyl)‐3,3,5,5‐tetramethylpyrrolidin‐2‐yliden), their oxidized Ni(I) analogues [NiI(Mes2Im)2][BPh4] 1+, [NiI(Mes2ImH2)2][BPh4] 2+, [NiI(Dipp2Im)2][BPh4] 3+, [NiI(Dipp2ImH2)2][BPh4] 4+ and [NiI(cAACMe)2][BPh4] 5+ were synthesized by one‐electron oxidation with ferrocenium tetraphenyl‐borate. The complexes 1+–5+ were fully characterized including X‐ray structure analysis. The complex cations reveal linear geometries in the solid state and NMR spectra with extremely broad, paramagnetically shifted resonances. DFT calculations predicted an orbitally degenerate ground state leading to large magnetic anisotropy, which was verified by EPR measurements in solution and on solid samples. The magnetic anisotropy of the complexes is highly dependent from the steric protection of the metal atom, which results in a noticeable decrease of the g‐tensor anisotropy for the N‐Mes substituted complexes 1+ and 2+ in solution due to the formation of T‐shaped THF adducts. [ABSTRACT FROM AUTHOR]

Lattice structures are known for their superior performance in weight reduction, stiffness, and increased manufacturability, but when materials need to be adaptive, multifunctional, and with tunable properties, functionally graded lattice structures (FGLS) play a crucial role in innovative solutions. Recent digital manufacturing technologies offer ideal conditions for creating lattice structures with high geometrical complexity and functional gradients. However, the design and development of these inherently complex structures often require the use of specialized methods and software tools. As researchers venture from diverse areas into the research of FGLS in search of novel applications, it is important to choose adequate design tools. Herein, an overview of methods and software for the design of FGLS is presented, identifying geometrical parameters of common lattice topologies and ways to manipulate them to create functional gradients. Fifty software applications or methods are listed, dedicated to the design of single material lattices produced by additive manufacturing processes. Typical applications of the reviewed software are identified, and FGLS design methods are compared. Generative Design seems more suited as an explorative process, Topology Optimization is an established efficiency‐focused design process, and Machine Learning is considered a promising data‐driven approach for the design of innovative FGLS. [ABSTRACT FROM AUTHOR]

The numerical techniques required to prove the single‐photon emission from any type of quantum emitter (QE) after being coupled to any nanostructure are presented in this paper. The Purcell effect modifies the emission characteristics of QEs, such as color centers in nanodiamonds, for example, nitrogen‐vacancy (NV) centers, silicon vacancy (SiV) centers, and so forth, or semiconductor quantum dots. Our numerical approach is based on the unique QEs' experimental photophysics parameters and numerical analysis software, which are MATLAB and Quantum Toolbox in Python (QuTiP). Our results show a comparable g(2) (τ) behavior between our proposed numerical model and the other two experimental results for the QE before and after coupling to a plasmonic waveguide with subwavelength dimensions. Our proposed method is essential to prove the single‐photon emission of modeled single‐photon source (SPS) in an on‐chip polarization‐dependent quantum key distribution system (QKD). [ABSTRACT FROM AUTHOR]

Systemic environmental disadvantage relates to a host of health and functional outcomes. Specific structural factors have seldom been linked to neural structure, however, clouding understanding of putative mechanisms. Examining relations during childhood/preadolescence, a dynamic period of neurodevelopment, could aid bridge this gap. A total of 10,213 youth were recruited from the Adolescent Brain and Cognitive Development study. Self‐report and objective measures (Census and Federal bureau of investigation metrics extracted using geocoding) of environmental exposures were used, including stimulation indexing lack of safety and high attentional demands, discrepancy indexing social exclusion/lack of belonging, and deprivation indexing lack of environmental enrichment. Environmental measures were related to cortical thickness, surface area, and subcortical volume regions, controlling for other environmental exposures and accounting for other brain regions. Self‐report (|β| =.04–.09) and objective (|β| =.02–.06) environmental domains related to area/thickness in overlapping (e.g., insula, caudal anterior cingulate), and unique regions (e.g., for discrepancy, rostral anterior and isthmus cingulate, implicated in socioemotional functions; for stimulation, precuneus, critical for cue reactivity and integration of environmental cues; and for deprivation, superior frontal, integral to executive functioning). For stimulation and discrepancy exposures, self‐report and objective measures showed similarities in correlate regions, while deprivation exposures evidenced distinct correlates for self‐report and objective measures. Results represent a necessary step toward broader work aimed at establishing mechanisms and correlates of structural disadvantage, highlighting the relevance of going beyond aggregate models by considering types of environmental factors, and the need to incorporate both subjective and objective measurements in these efforts. [ABSTRACT FROM AUTHOR]

The activation and functionalization of C−F bonds in various fluoroorganics were found to be a daunting task owing to their innate inertness. Harnessing the C−F bonds will alleviate the toxicity and environmental issues posed by them, and provide new pathways to access value‐added products. Although several strategies have been employed such as metal complexes, Brønsted acids, Lewis acids, and photocatalyst to activate the C−F bonds, however, the use of NHC or Metal‐NHC is relatively scarce. NHCs based catalytic C−F activation stands out owing to its easy accessibility, stability, and facile reactivity. Metal‐NHCs were exploited in hydrodefluorination, C−C, and C−B coupling reactions. Additionally, R−M(F)(NHC), an oxidative‐addition intermediate that was conveniently isolated allows to decode catalytic C−F functionalization pathways. This minireview provides the prominence of NHC and metal‐NHC in the area of catalytic C−F bond functionalization. [ABSTRACT FROM AUTHOR]

A case study on the effect of the employment of two different NHC ligands in complexes [Ni(NHC)2] (NHC=iPr2ImMe1Me, Mes2Im 2) and their behavior towards alkynes is reported. The reaction of a mixture of [Ni2(iPr2ImMe)4(μ‐(η2 : η2)‐COD)] B/ [Ni(iPr2ImMe)2(η4‐COD)] B' or [Ni(Mes2Im)2] 2, respectively, with alkynes afforded complexes [Ni(NHC)2(η2‐alkyne)] (NHC=iPr2ImMe: alkyne=MeC≡CMe 3, H7C3C≡CC3H74, PhC≡CPh 5, MeOOCC≡CCOOMe 6, Me3SiC≡CSiMe37, PhC≡CMe 8, HC≡CC3H79, HC≡CPh 10, HC≡C(p‐Tol) 11, HC≡C(4‐tBu‐C6H4) 12, HC≡CCOOMe 13; NHC=Mes2Im: alkyne=MeC≡CMe 14, MeOOCC≡CCOOMe 15, PhC≡CMe 16, HC≡C(4‐tBu‐C6H4) 17, HC≡CCOOMe 18). Unusual rearrangement products 11 a and 12 a were identified for the complexes of the terminal alkynes HC≡C(p‐Tol) and HC≡C(4‐tBu‐C6H4), 11 and 12, which were formed by addition of a C−H bond of one of the NHC N‐iPr methyl groups to the C≡C triple bond of the coordinated alkyne. Complex 2 catalyzes the cyclotrimerization of 2‐butyne, 4‐octyne, diphenylacetylene, dimethyl acetylendicarboxylate, 1‐pentyne, phenylacetylene and methyl propiolate at ambient conditions, whereas 1Me is not a good catalyst. The reaction of 2 with 2‐butyne was monitored in some detail, which led to a mechanistic proposal for the cyclotrimerization at [Ni(NHC)2]. DFT calculations reveal that the differences between 1Me and 2 for alkyne cyclotrimerization lie in the energy profile of the initiation steps, which is very shallow for 2, and each step is associated with only a moderate energy change. The higher stability of 3 compared to 14 is attributed to a better electron transfer from the NHC to the metal to the alkyne ligand for the N‐alkyl substituted NHC, to enhanced Ni‐alkyne backbonding due to a smaller CNHC−Ni−CNHC bite angle, and to less steric repulsion of the smaller NHC iPr2ImMe. [ABSTRACT FROM AUTHOR]

The activation of a carbon‐fluorine bond is one of the most challenging topics in modern synthetic organic chemistry due to their low reactivity compared to other carbon‐halogen bonds. In this review, we present the recent developments since 2015 on cross‐coupling reactions that form C−C bonds via cleavage of C(sp2)−F bonds. Not only the conventional activation of C(sp2)−F bonds, but also decarbonylative or carbonyl‐retentive cleavage of C(acyl)−F bonds will be introduced. This paper mainly describes new protocols for the formation of C(sp2)−C(sp3), C(sp2)−C(sp2), and C(sp2)−C(sp) bonds via transition‐metal‐catalyzed cleavage of C(sp2)−F bonds. [ABSTRACT FROM AUTHOR]

The addition of PPh2H, PPhMeH, PPhH2, P(para‐Tol)H2, PMesH2 and PH3 to the two‐coordinate Ni0 N‐heterocyclic carbene species [Ni(NHC)2] (NHC=IiPr2, IMe4, IEt2Me2) affords a series of mononuclear, terminal phosphido nickel complexes. Structural characterisation of nine of these compounds shows that they have unusual trans [H−Ni−PR2] or novel trans [R2P−Ni−PR2] geometries. The bis‐phosphido complexes are more accessible when smaller NHCs (IMe4>IEt2Me2>IiPr2) and phosphines are employed. P−P activation of the diphosphines R2P−PR2 (R2=Ph2, PhMe) provides an alternative route to some of the [Ni(NHC)2(PR2)2] complexes. DFT calculations capture these trends with P−H bond activation proceeding from unconventional phosphine adducts in which the H substituent bridges the Ni−P bond. P−P bond activation from [Ni(NHC)2(Ph2P−PPh2)] adducts proceeds with computed barriers below 10 kcal mol−1. The ability of the [Ni(NHC)2] moiety to afford isolable terminal phosphido products reflects the stability of the Ni−NHC bond that prevents ligand dissociation and onward reaction. [ABSTRACT FROM AUTHOR]

Deficits in facial emotion recognition occur frequently after stroke, with adverse social and behavioural consequences. The aim of this study was to investigate the neural underpinnings of the recognition of emotional expressions, in particular of the distinct basic emotions (anger, disgust, fear, happiness, sadness and surprise). A group of 110 ischaemic stroke patients with lesions in (sub)cortical areas of the cerebrum was included. Emotion recognition was assessed with the Ekman 60 Faces Test of the FEEST. Patient data were compared to data of 162 matched healthy controls (HC's). For the patients, whole brain voxel‐based lesion–symptom mapping (VLSM) on 3‐Tesla MRI images was performed. Results showed that patients performed significantly worse than HC's on both overall recognition of emotions, and specifically of disgust, fear, sadness and surprise. VLSM showed significant lesion–symptom associations for FEEST total in the right fronto‐temporal region. Additionally, VLSM for the distinct emotions showed, apart from overlapping brain regions (insula, putamen and Rolandic operculum), also regions related to specific emotions. These were: middle and superior temporal gyrus (anger); caudate nucleus (disgust); superior corona radiate white matter tract, superior longitudinal fasciculus and middle frontal gyrus (happiness) and inferior frontal gyrus (sadness). Our findings help in understanding how lesions in specific brain regions can selectively affect the recognition of the basic emotions. [ABSTRACT FROM AUTHOR]

Lattice structure has a broad application in the fields of aerospace, automobile, bio‐medical treatment and energy. It is very suitable for the applications of secondary load‐bearing components, because of its characteristics of low density, high specific strength, and high specific stiffness. The flexural property is an important index of the material used in the secondary load‐bearing components. In this study, the flexural properties of ARCH lattice structure fabricated by selective laser melting (SLM) under different loading directions and with different relative densities are simulated and experimentally researched. The results show that ARCH lattice structure has better flexural properties under Y loading direction. The relative density has a great influence on the flexural properties of ARCH lattice structures. Moreover, the Gibson–Ashby equation is also established to estimate the flexural properties of the lattice structures with different relative densities, which can provide a theoretical basis and reference to the engineering application of ARCH lattice structures. [ABSTRACT FROM AUTHOR]

The synthesis and characterization of Lewis acid/base adducts between tris(pentafluoroethyl)difluorophosphorane PF2(C2F5)3 and selected N‐heterocyclic carbenes (NHCs) R2Im (1,3‐di‐organyl‐imidazolin‐2‐ylidene) and phosphines are reported. For NHCs with small alkyl substituents at nitrogen (R=Me, nPr, iPr) the adducts NHC ⋅ PF2(C2F5)3 (2 a–h) were isolated. The reaction with the sterically more demanding NHCs Dipp2Im (1,3‐bis‐(2,6‐di‐iso‐propylphenyl)‐imidazolin‐2‐ylidene) (1 i) and tBu2Im (1,3‐di‐tert‐butyl‐imidazolin‐2‐ylidene) (1 j) afforded the aNHC adducts 3 i and 3 j (a denotes "abnormal" NHC coordination via a backbone carbon atom). The use of tBuMeIm (1‐tert‐butyl‐3‐methyl‐imidazolin‐2‐ylidene) (1 m) led to partial decomposition of the NHC and formation of the salt [tBuMeIm−H][MeIm ⋅ PF2(C2F5)3] (4 m). The phosphorane PF2(C2F5)3 forms adducts with PMe3 but does not react with PPh3 or PCy3. The mer‐cis isomer of literature‐known Me3P ⋅ PF2(C2F5)3 (5 a) was structurally characterized. Mixtures of the phosphorane PF2(C2F5)3 and the sterically encumbered NHCs tBu2Im, Dipp2Im, and Dipp2ImH2 (1,3‐bis‐(2,6‐di‐iso‐propylphenyl)‐imidazolidin‐2‐ylidene) (1 k) showed properties of FLPs (Frustrated Lewis Pairs) as these mixtures were able to open the ring of THF (tetrahydrofuran) to yield NHC−(CH2)4O−PF2(C2F5)36 i–k. Furthermore, the deprotonation of the weak C−H acids CH3CN, acetone, and ethyl acetate was achieved, which led to the formation of the corresponding imidazolium salts and the phosphates [PF2(C2F5)3(CH2CN)]− (7), [PF2(C2F5)3(OC(=CH2)CH3)]− (8) and [PF2(C2F5)3(CH2CO2Et)]− (9). [ABSTRACT FROM AUTHOR]

Myokines are muscle‐derived cytokines and chemokines that act extensively on organs and exert beneficial metabolic functions in the whole‐body through specific signal networks. Myokines as mediators provide the conceptual basis for a whole new paradigm useful for understanding how skeletal muscle communicates with other organs. In this review, we summarize and discuss classes of myokines and their physiological functions in mediating the regulatory roles of skeletal muscle on other organs and the regulation of the whole‐body energy metabolism. We review the mechanisms involved in the interaction between skeletal muscle and nonmuscle organs through myokines. Moreover, we clarify the connection between exercise, myokines and disease development, which may contribute to the understanding of a potential mechanism by which physical inactivity affects the process of metabolic diseases via myokines. Based on the current findings, myokines are important factors that mediate the effect of skeletal muscle on other organ functions and whole‐body metabolism. [ABSTRACT FROM AUTHOR]

Fluoride abstraction from different types of transition metal fluoride complexes [LnMF] (M=Ti, Ni, Cu) by the Lewis acid tris(pentafluoroethyl)difluorophosphorane (C2F5)3PF2 to yield cationic transition metal complexes with the tris(pentafluoroethyl)trifluorophosphate counterion (FAP anion, [(C2F5)3PF3]−) is reported. (C2F5)3PF2 reacted with trans‐[Ni(iPr2Im)2(ArF)F] (iPr2Im=1,3‐diisopropylimidazolin‐2‐ylidene; ArF=C6F5, 1 a; 4‐CF3‐C6F4, 1 b; 4‐C6F5‐C6F4, 1 c) through fluoride transfer to form the complex salts trans‐[Ni(iPr2Im)2(solv)(ArF)]FAP (2 a‐c[solv]; solv=Et2O, CH2Cl2, THF) depending on the reaction medium. In the presence of stronger Lewis bases such as carbenes or PPh3, solvent coordination was suppressed and the complexes trans‐[Ni(iPr2Im)2(PPh3)(C6F5)]FAP (trans‐2 a[PPh3]) and cis‐[Ni(iPr2Im)2(Dipp2Im)(C6F5)]FAP (cis‐2 a[Dipp2Im]) (Dipp2Im=1,3‐bis(2,6‐diisopropylphenyl)imidazolin‐2‐ylidene) were isolated. Fluoride abstraction from [(Dipp2Im)CuF] (3) in CH2Cl2 or 1,2‐difluorobenzene led to the isolation of [{(Dipp2Im)Cu}2]2+2 FAP− (4). Subsequent reaction of 4 with PPh3 and different carbenes resulted in the complexes [(Dipp2Im)Cu(LB)]FAP (5 a–e, LB=Lewis base). In the presence of C6Me6, fluoride transfer afforded [(Dipp2Im)Cu(C6Me6)]FAP (5 f), which serves as a source of [(Dipp2Im)Cu)]+. Fluoride abstraction of [Cp2TiF2] (7) resulted in the formation of dinuclear [FCp2Ti(μ‐F)TiCp2F]FAP (8) (Cp=η5‐C5H5) with one terminal fluoride ligand at each titanium atom and an additional bridging fluoride ligand. [ABSTRACT FROM AUTHOR]

A catalytic defluorinative hydroarylation of alkenes with polyfluoroarenes in the presence of dppbz‐ligated Cu catalyst and silanes was developed. This method provides a straightforward and alternative avenue to synthetic important polyfluorinated arenes with readily available and bench‐stable alkenes as latent nucleophiles, and therefore avoids conventional reliance on stoichiometric quantities of organometallic reagents. This reaction proceeds under very mild conditions and exhibits good functional group compatibility and high level of regioselectivity. The synthetic potential of this method was further demonstrated by a gram‐scale synthesis, and an array of experimental studies were also carried out to elaborate the probable mechanism. [ABSTRACT FROM AUTHOR]

A catalytic defluorinative hydroarylation of alkenes with polyfluoroarenes in the presence of dppbz‐ligated Cu catalyst and silanes was developed. This method provides a straightforward and alternative avenue to synthetic important polyfluorinated arenes with readily available and bench‐stable alkenes as latent nucleophiles, and therefore avoids conventional reliance on stoichiometric quantities of organometallic reagents. This reaction proceeds under very mild conditions and exhibits good functional group compatibility and high level of regioselectivity. The synthetic potential of this method was further demonstrated by a gram‐scale synthesis, and an array of experimental studies were also carried out to elaborate the probable mechanism. [ABSTRACT FROM AUTHOR]

The work describes unexpected stoichiometric C–F bond cleavage reactions of beryllium, magnesium, gallium, hafnium and thorium halides with α,α,α‐trifluorotoluene. The reaction of BeBr2 / GaBr3 or MgBr2 / GaBr3 mixtures as well as neat GaI3 with α,α,α‐trifluorotoluene in the presence of (OSi2Me4)2 (I) yields the carbenium ion containing compounds [Ph‐C(O2Si2Me4)][GaX4] (X = Br: 1, X = I/F: 2). Both compounds were successfully characterized and a defluorination type reaction under incorporation of a siloxy unit was observed. Compound 1 was also characterized by single‐crystal X‐ray diffraction analysis. The conversion of α,α,α‐trifluorotoluene with BeI2, HfI4 or ThI4 turned out to be a halodefluorination‐type reaction with formation of α,α,α‐triiodotoluene (3). An adequate NMR spectroscopic and the X‐ray crystallographic characterization of 3 were performed for the first time. [ABSTRACT FROM AUTHOR]

Investigations concerning the reactivity of Ni(0) complexes [Ni(NHC)2] of NHCs (N‐heterocyclic carbene) of different steric demand, Mes2Im (= 1,3‐dimesitylimidazoline‐2‐ylidene) and iPr2Im (= 1,3‐diisopropyl‐imidazoline‐2‐ylidene), with olefins, ketones and aldehydes are reported. The reaction of [Ni(Mes2Im)2] 1 with ethylene or methyl acrylate afforded the complexes [Ni(Mes2Im)2(η2‐C2H4)] 3 and [Ni(Mes2Im)2(η2‐(C,C)‐H2C=CHCOOMe)] 4, as it was previously reported for [Ni2(iPr2Im)4(µ‐(η2:η2)‐COD)] 2 as a source for [Ni(iPr2Im)2]. In contrast to 2, complex 1 does not react with sterically more demanding olefins such as tetramethylethylene, 1,1‐diphenylethylene and cyclohexene. The reaction of [Ni(NHC)2] with more π‐acidic ketones or aldehydes led to formation of complexes with side‐on η2‐(C,O)‐coordinating ligands: [Ni(iPr2Im)2(η2‐O=CHtBu)] 5, [Ni(iPr2Im)2(η2‐O=CHPh)] 6, [Ni(iPr2Im)2(η2‐O=CMePh)] 7, [Ni(iPr2Im)2(η2‐O=CPh2)] 8, [Ni(iPr2Im)2(η2‐O=C(4‐F‐C6H4)2)] 9, [Ni(iPr2Im)2(η2‐O=C(OMe)(CF3))] 10 and [Ni(Mes2Im)2(η2‐O=CHPh)] 11, [Ni(Mes2Im)2(η2‐O=CH(CH(CH3)2))] 12, [Ni(Mes2Im)2(η2‐O=CH(4‐NMe2‐C6H4))] 13, [Ni(Mes2Im)2(η2‐O=CH(4‐OMe‐C6H4))] 14, [Ni(Mes2Im)2(η2‐O=CPh2)] 15 and [Ni(Mes2Im)2(η2‐O=C(4‐F‐C6H4)2)] 16. The reaction of 1 and 2 with these simple aldehydes and ketones does not lead to a significantly different outcome, but NHC ligand rotation is hindered for the Mes2Im complexes 3, 4 and 11–16 according to NMR spectroscopy. The solid‐state structures of 3, 4, 11 and 12 reveal significantly larger CNHC‐Ni‐CNHC angles in the Mes2Im complexes compared to the iPr2Im complexes. As electron transfer in d8‐ (or d10‐) ML2 complexes to π‐acidic ligands depends on the L–M–L bite angle, the different NHCs lead thus to a different degree of electron transfer and activation of the olefin, aldehyde or ketone ligand, i.e., [Ni(iPr2Im)2] is the better donor to these π‐acidic ligands. Furthermore, we identified two different side products from the reaction of 1 with benzaldehyde, trans‐[Ni(Mes2Im)2H(OOCPh)] 17 and [Ni2(Mes2Im)2(µ2‐CO)(µ2‐η2‐C,O‐PhCOCOPh)] 18, which indicate that radical intermediates and electron transfer processes might be of importance in the reaction of 1 with aldehydes and ketones. [ABSTRACT FROM AUTHOR]

A study on the reactivity of the N‐heterocyclic silylene Dipp2NHSi (1,3‐bis(diisopropylphenyl)‐1,3‐diaza‐2‐silacyclopent‐4‐en‐2‐yliden) with the transition metal complexes [Ni(CO)4], [M(CO)6] (M=Cr, Mo, W), [Mn(CO)5(Br)] and [(η5‐C5H5)Fe(CO)2(I)] is reported. We demonstrate that N‐heterocyclic silylenes, the higher homologues of the now ubiquitous NHC ligands, show a remarkably different behavior in coordination chemistry compared to NHC ligands. Calculations on the electronic features of these ligands revealed significant differences in the frontier orbital region which lead to some peculiarities of the coordination chemistry of silylenes, as demonstrated by the synthesis of the dinuclear, NHSi‐bridged complex [{Ni(CO)2(μ‐Dipp2NHSi)}2] (2), complexes [M(CO)5(Dipp2NHSi)] (M=Cr 3, Mo 4, W 5), [Mn(CO)3(Dipp2NHSi)2(Br)] (9) and [(η5‐C5H5)Fe(CO)2(Dipp2NHSi‐I)] (10). DFT calculations on several model systems [Ni(L)], [Ni(CO)3(L)], and [W(CO)5(L)] (L=NHC, NHSi) reveal that carbenes are typically the much better donor ligands with a larger intrinsic strength of the metal–ligand bond. The decrease going from the carbene to the silylene ligand is mainly caused by favorable electrostatic contributions for the NHC ligand to the total bond strength, whereas the orbital interactions were often found to be higher for the silylene complexes. Furthermore, we have demonstrated that the contribution of σ‐ and π‐interaction depends significantly on the system under investigation. The σ‐interaction is often much weaker for the NHSi ligand compared to NHC but, interestingly, the π‐interaction prevails for many NHSi complexes. For the carbonyl complexes, the NHSi ligand is the better σ‐donor ligand, and contributions of π‐symmetry play only a minor role for the NHC and NHSi co‐ligands. [ABSTRACT FROM AUTHOR]

The reaction of zerovalent nickel compounds with white phosphorus (P4) is a barely explored route to binary nickel phosphide clusters. Here, we show that coordinatively and electronically unsaturated N‐heterocyclic carbene (NHC) nickel(0) complexes afford unusual cluster compounds with P1, P3, P5 and P8 units. Using [Ni(IMes)2] [IMes=1,3‐bis(2,4,6‐trimethylphenyl)imidazolin‐2‐ylidene], electron‐deficient Ni3P4 and Ni3P6 clusters have been isolated, which can be described as superhypercloso and hypercloso clusters according to the Wade–Mingos rules. Use of the bulkier NHC complexes [Ni(IPr)2] or [(IPr)Ni(η6‐toluene)] [IPr=1,3‐bis(2,6‐diisopropylphenyl)imidazolin‐2‐ylidene] affords a closo‐Ni3P8 cluster. Inverse‐sandwich complexes [(NHC)2Ni2P5] (NHC=IMes, IPr) with an aromatic cyclo‐P5− ligand were identified as additional products. [ABSTRACT FROM AUTHOR]

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A novel, useful in situ synthesis for NHC nickel allyl halide complexes [Ni(NHC)(η3‐allyl)(X)] starting from [Ni(CO)4], NHC and allyl halides is presented. The reaction of [Ni(CO)4] with (i) one equivalent of the corresponding NHC and (ii) with an excess of the corresponding allyl chloride at room temperature leads with elimination of carbon monoxide to complexes of the type [Ni(NHC)(η3‐allyl)(X)]. This approach was used to synthesize the complexes [Ni(tBu2Im)(η3‐H2C‐C(Me)‐CH2)(Cl)] (2), [Ni(iPr2ImMe)(η3‐H2C‐C(Me)‐CH2)(Cl)] (3), [Ni(iPr2Im)(η3‐H2C‐C(Me)‐CH2)(Cl)] (4), [Ni(iPr2Im)(η3‐H2C‐C(H)‐C(Me)2)(Br)] (5), [Ni(Me2ImMe)(η3‐H2C‐C(Me)‐CH2)(Cl)] (6), and [Ni(EtiPrImMe)(η3‐H2C‐C(Me)‐CH2)(Cl)] (7). The complexes 1 to 7 were characterized using NMR and IR spectroscopy and elemental analysis, and the molecular structures are provided for 2 and 7. The allyl nickel complexes 1–7 are stereochemically non‐rigid in solution due to (i) NHC rotation about the nickel‐carbon bond, (ii) allyl rotation about the Ni–η3‐allyl axis and (iii) π–σ–π allyl isomerization processes. The allyl halide complexes can be methylated as was demonstrated by the methylation of a number of the complexes [Ni(NHC)(η3‐allyl)(X)] with methylmagnesium chloride or methyllithium, which led to isolation of the complexes [Ni(Me2Im)(η3‐H2C‐C(Me)‐CH2)(Me)] (8), [Ni(tBu2Im)(η3‐H2C‐C(Me)‐CH2)(Me)] (9), [Ni(iPr2ImMe)(η3‐H2C‐C(Me)‐CH2)(Me)] (10), [Ni(iPr2Im)(η3‐H2C‐C(Me)‐CH2)(Me)] (11), [Ni(iPr2Im)(η3‐H2C‐C(H)‐C(Me)2)(Me)] (12), and [Ni(EtiPrImMe)(η3‐H2C‐C(Me)‐CH2)(Me)] (13). These complexes were fully characterized including X‐ray molecular structures for 10 and 11. [ABSTRACT FROM AUTHOR]

It has been recently demonstrated that yeast cells are able to partially regress chromosome segregation in telophase as a response to DNA double‐strand breaks (DSBs), likely to find a donor sequence for homology‐directed repair (HDR). This regression challenges the traditional concept that establishes anaphase events as irreversible, hence opening a new field of research in cell biology. Here, the nature of this new behavior in yeast is summarized and the underlying mechanisms are speculated about. It is also discussed whether it can be reproduced in other eukaryotes. Overall, this work brings forwards the need of understanding how cells attempt to repair DSBs when transiting the latest stages of mitosis, i.e., anaphase and telophase. [ABSTRACT FROM AUTHOR]

The head‐to‐tail autocondensation of 4‐fluoroacetophenone in the KOH/DMSO superbase suspension stops on dimerization step affording 4‐acetylbenzyl‐4'‐fluorophenylketone in 96 % yield. Further condensation of the diketone formed is prevented by a weaker electron‐withdrawing effect of enolate spacer, –CH=C(OK)–. 2‐Fluoro‐ and 3‐fluoroacetophenones are inactive in this reaction. Other superbases of the type MOR/DMSO (M = Na, K; R = H, OBut) are inferior in promotion of this reaction providing 71–76 % yields of the dimeric ketone. Other weak acids like non‐fluorinated acylbenzenes prove to be also capable of forming Csp2–Csp3 bond with 4‐fluoroacetophenone under similar conditions. This new group of fluorine substitution (SNAr) reaction opens a short and simple route to so far inaccessible aromatic diketones via the nucleophilic substitution of fluorine atom in 4‐fluoroacetophenone by available acylbenzenes. The quantum‐chemical rationale of the observed substitution process as competing with aldol condensation is suggested. [ABSTRACT FROM AUTHOR]

Due to advances in captive nonhuman primate (NHP) medical care, the number of geriatric chimpanzees (≥35‐years old) is growing. With old age comes a variety of physical conditions, including arthritis, stroke, and mobility impairments. Programs aimed at enhancing the welfare of geriatric chimpanzees are now quite common, but there are few published empirical evaluations of the efficacy of such programs. The current study aimed to create, implement, and evaluate the effects of participation in a physical therapy (PT) program on physical health, mobility, welfare, and behavior. Nine chimpanzees with mobility impairments participated in personalized PT routines (using positive reinforcement training) twice per week for 5 months. Additionally, nine control chimpanzees (non‐mobility‐impaired, matched with PT chimpanzees on age and gender) participated in body exam behavior sessions (also using positive reinforcement training) twice per week. All chimpanzees were rated on 14 health, well‐being, and behavior items, as well as level of mobility throughout the PT program. Chimpanzees that participated in the PT program showed significant increases in ratings of physical health, well‐being, and activity levels across phases of the program. Furthermore, compared to control chimpanzees, PT chimpanzees showed significant increases in ratings of ease of movement. Because raters were not blind to physical therapy treatment, our results represent an initial evaluation of the program that may suggest that participation in the PT program has physical, behavioral, and welfare benefits. Assessments of novel geriatric‐focused care strategies and programs are essential to further enhance the welfare of the captive chimpanzee population, which is currently comprised of many geriatric animals, whose proportion of the captive population will only increase. Research Highlights: Twice per week, nine mobility‐impaired chimpanzees participated in physical therapy sessions, including squats, weight shifts, standing, and stretching exercises, and nine control chimpanzees participated in positive reinforcement training sessions.Among chimpanzees that participated in physical therapy, results showed significant increases in physical health, well‐being, ease of movement, and activity levels across successive phases of the program. [ABSTRACT FROM AUTHOR]

The reaction of sym‐dimethyltetraphenyl carbodiphosphorane (CDPMe) with [Ni(CO)4] under standard conditions yields the CDPMe‐ and carbon monoxide‐bridged dinickel pentacarbonyl complex [Ni2(CO)4(µ2‐CO)(µ2‐CDPMe)] (2). However, under an atmosphere of CO(g), reaction of [Ni(CO)4] with CDPMe gives the primal target complex [CDPMe‐Ni(CO)3] (3). The complexes were examined in solution (ESI‐MS, NMR) and in the solid state (IR, X‐ray diffraction analysis). The resulting Tolman electronic parameter (TEP) and percentage buried volume value (%Vbur) of CDPMe are presented and compared with hexaphenyl carbodiphosphorane (CDPPh). DFT calculations were performed to analyze the bonding situation in complexes 2 and 3. [ABSTRACT FROM AUTHOR]

We herein demonstrate that the amide base generated in situ from CsF and N(TMS)3 catalyzes the deprotonative coupling reactions of terminal alkynes with polyfluoroarenes, wherein mono‐ and dialkynylations occur efficiently for penta‐ and hexafluorobenzenes, respectively. Tetraalkynylated products could also be synthesized from dialkynylated compounds. [ABSTRACT FROM AUTHOR]

The reactivity of [Ni(iPr2Im)4(µ‐COD)] 1 (iPr2Im = 1,3‐diisopropyl‐imidazolin‐2‐ylidene, COD = 1,4‐cyclooctadiene) in Hiyama‐ and Negishi‐type cross‐coupling reactions as well as the synthesis of several novel nickel fluoroaryl alkyl complexes is reported. Hiyama coupling of 1.1 equiv. perfluoroaromatics and 1 equiv. PhSi(OR)3 (R = Me, Et) with 5 mol‐% of 1 as catalyst leads to the C–C coupling product ArF–Ph in good to fair yields. In presence of the additive NMe4F alkoxy transfer from PhSi(OR)3 to the perfluoroarene occurs to yield ArF–OR and PhSiF(OR)2. Negishi cross‐coupling between C6F6 or C7F8 (1 equiv.), diorganozinc reagents [ZnR2] (R = Me, Et) (2.1 equiv.) and 5 mol‐% 1 as the catalyst in toluene at 115 °C leads to ArF–R only in traces. However, NMR experiments revealed that nickel alkyl complexes are readily formed from the reaction of trans‐[Ni(iPr2Im)2(F)(ArF)] with [ZnR2] (R = Me, Et). In course of these investigations, a series of novel nickel alkyl complexes trans‐[Ni(iPr2Im)2(R)(ArF)] (R = Me, ArF = C6F52, C7F73, C12F94; R = Et, ArF = C6F55, C7F76, C12F97) have been synthesized in stoichiometric reactions starting from trans‐[Ni(iPr2Im)2(F)(ArF)] (ArF = C6F5, C7F7, C12F9) and [ZnR2] (R = Me, Et) in thf at –78 °C. As these nickel alkyl complexes 2–7 are stable at room temperature in solution for several days with respect to reductive elimination, their thermal stability was investigated. Heating trans‐[Ni(iPr2Im)2(Me)(C6F5)] 2 for 24 hours at 100 °C leads to 91 % unreacted complex 2 and only traces of reductive elimination product, i.e. C6F5Me, are formed. Furthermore, the nickel ethyl complex trans‐[Ni(iPr2Im)2(Et)(C6F5)] 5 is also very stable, even with respect to β‐hydride elimination. After heating this complex to 100 °C for 24 hours there is still 26 % unreacted 5 left. The reactivity of [Ni(iPr2Im)4(µ‐COD)] 1 (iPr2Im = 1,3‐diisopropyl‐imidazolin‐2‐ylidene, COD = 1,4‐cyclooctadiene) in Hiyama‐ and Negishi‐type cross‐coupling reactions of perfluoroaromatics as well as the synthesis and investigations concerning the stability in solution of several novel nickel fluoroaryl alkyl complexes is reported. [ABSTRACT FROM AUTHOR]

A β‐diketiminato‐based tridentate pincer‐type nickel(II) complex Ni‐NNP was prepared by the reaction of the nickel(II) precursor [NiCl2(2,4‐lutidine)2] with the lithiated NNP ligand, which was generated in situ by the reaction of the NNP pro‐ligand H‐NNP with nBuLi. H‐NNP was prepared by the condensation of 4‐[(2,4,6‐trimethylphenyl)amino]pent‐3‐en‐2‐one with 2‐(diphenylphosphanyl)ethylamine. Ni‐NNP was characterized spectroscopically and by X‐ray diffraction, revealing a slightly distorted square‐planar geometry around the nickel center. Density functional theory calculations indicated that the highest occupied molecular orbital in Ni‐NNP is located at higher energy than those of three other homologous nickel(II) complexes, i.e., Ni‐ONN, Ni‐ONP, and Ni‐NNN, which contain β‐aminoketonato‐ or β‐diketiminato‐based pincer‐type ligands. The electronic and steric properties of Ni‐NNP effectively facilitated the cross‐coupling of aryl fluorides with aryl Grignard reagents. A β‐diketiminato‐based pincer‐type nickel(II) complex was synthesized, and its catalytic performance in the cross‐coupling of aryl fluorides with aryl Grignard reagents was investigated. [ABSTRACT FROM AUTHOR]

Dopamine‐ and cAMP‐regulated phosphoprotein (Mr 32 kDa, DARPP‐32) is an integrator of multiple neuronal signals and plays a crucial role particularly in mediating the dopaminergic component of the systems involved in the evaluation of stimuli and the ensuing elaboration of complex behavioral responses (e.g., responses to reinforcers and stressors). Dopamine neurons can fire tonically or phasically in distinct timescales and in specific brain regions to code different behaviorally relevant information. Dopamine signaling is mediated mainly through the regulation of adenylyl cyclase activity, stimulated by D1‐like or inhibited by D2‐like receptors, respectively, that modulates cAMP‐dependent protein kinase (PKA) function. The activity of DARPP‐32 is finely regulated by its phosphorylation at multiple sites. Phosphorylation at the threonine (Thr) 34 residue by PKA converts DARPP‐32 into an inhibitor of protein phosphatase 1, while the phosphorylation at the Thr75 residue turns it into an inhibitor of PKA. Thus, DARPP‐32 is critically implicated in regulating striatal output in response to the convergent pathways that influence signaling of the cAMP/PKA pathway. This review summarizes some of the landmark and recent studies of DARPP‐32‐mediated signaling in the attempt to clarify the role played by DARPP‐32 in the response to rewarding natural stimuli. Particularly, the review deals with data derived from rodents studies and discusses the involvement of the cAMP/PKA/DARPP‐32 pathway in: 1) appetitive food‐sustained motivated behaviors, 2) motivated behaviors sustained by social reward, 3) sexual behavior, and 4) responses to environmental enrichment. Dopamine‐ and cAMP‐regulated phosphoprotein (Mr 32 kDa, DARPP‐32) is an integrator of multiple neuronal signals, in particular of dopaminergic and glutamatergic transmissions, and its activity is finely regulated by phosphorylation at multiple sites [threonine (Thr) 34 and 75; serine (Ser) 97 and 130]. This review discusses the role of DARPP‐32 in mediating biochemical, electrophysiological, transcriptional, and behavioral effects of dopamine. The evidences available on rodents, and some indirect evidence in humans, on the role played by DARPP‐32 in the integration of the responses to rewarding natural stimuli such as food, social and sexual interactions, and environmental enrichment are presented. [ABSTRACT FROM AUTHOR]

We present herein the utilization of NHC‐stabilized alane adducts of the type (NHC)·AlH3 [NHC = Me2Im (1), Me2ImMe (2), iPr2Im (3), iPr2ImMe (4), Dipp2Im (5)] and (NHC)·AliBu2H [NHC = iPr2Im (6), Dipp2Im (7)] as novel hydride transfer reagents in the hydrodefluorination (HDF) of different fluoroaromatics and hexafluoropropene. Depending on the alane adduct used, HDF of pentafluoropyridine to 2,3,5,6‐tetrafluoropyridine in yields of 15–99 % was observed. The adducts 1, 2, and 5 achieved a quantitative conversion into 2,3,5,6‐tetrafluoropyridine at room temperature immediately after mixing the reactants. Studies on the HDF of fluorobenzenes with the (NHC)·AlH3 adducts 1, 3, and 5 and (Dipp2Im)·AliBu2H (7) showed the decisive influence of the reaction temperature on the H/F exchange and that 135 °C in xylene afforded the best product distribution. Although the HDF of hexafluorobenzene yielded 1,2,4,5‐tetrafluorobenzene in moderate yields with traces of 1,2,3,4‐tetrafluorobenzene and 1,2,4‐trifluorobenzene, pentafluorobenzene was converted quantitatively into 1,2,4,5‐tetrafluorobenzene, with (Dipp2Im)·AliBu2H (7) showing the highest activity and reaching complete conversion after 12 h at 135 °C in xylene. The HDF of hexafluoropropene with (Me2Im)·AlH3 (1) occurred even at low temperatures and preferably at the CF2 group with the formation of 1,2,3,3,3‐pentafluoropropene (with 0.4 equiv. of 1) or 2,3,3,3‐tetra‐fluoropropene (with 0.9 equiv. of 1) as the main product. [ABSTRACT FROM AUTHOR]

A Ni-catalyzed C-F bond functionalization of unactivated aryl fluorides with oxazoles as coupling partners was developed. Various arylated oxazoles could be obtained in moderate to good yields in the presence of Ni(cod)2/IMes catalytic system. A rapid synthesis of natural product texaline was also demonstrated using this protocol. This transformation could be potentially utilized in regioselective introduction of an oxazole group in late-stage synthetic applications. [ABSTRACT FROM AUTHOR]

Readily accessed cobalt pre-catalysts with N-heterocyclic carbene ligands catalyze the Suzuki cross-coupling of aryl chlorides and bromides with alkyllithium-activated arylboronic pinacolate esters. Preliminary mechanistic studies indicate that the cobalt species is reduced to Co0 during the reaction. [ABSTRACT FROM AUTHOR]

Readily accessed cobalt pre-catalysts with N-heterocyclic carbene ligands catalyze the Suzuki cross-coupling of aryl chlorides and bromides with alkyllithium-activated arylboronic pinacolate esters. Preliminary mechanistic studies indicate that the cobalt species is reduced to Co0 during the reaction. [ABSTRACT FROM AUTHOR]

The first synthesis of cyclic (alkyl)(amino)carbenes (cAACs) was reported in 2005, and since then this class of carbenes has been on a victory tour in main-group-element and transition-metal chemistry. CAACs are easy to synthesize and among the most nucleophilic (s-donating) and simultaneously most electrophilic (p-accepting) carbenes known to date. These properties have led to a vast number of applications of cAACs in main-group-element chemistry in, for example, the activation of small-molecule compounds and enthalpically strong bonds, as well as in the stabilization of highly reactive main-groupelement compounds. They also proved to possess outstanding ligand properties in transition-metal chemistry in, for example, the stabilization of unusual low-valent transition-metal complexes, leading to enormously highly active but robust catalysts. Here a brief overview of cAAC-ligated transition-metal compounds, mainly in low oxidation states, with an emphasis on nickel complexes, is provided, and a personal account of some of the recent developments in the use of cAACs in coordination chemistry and catalysis is given. [ABSTRACT FROM AUTHOR]

Motor and nonmotor symptoms associated with Parkinson disease place individuals at greater risk of sedentary behaviors and comorbidities. Physical activity is one modifiable means of improving health and reducing the risk of morbidity. We applied a behavioral framework to classify existing research on physical activity and Parkinson disease to describe the current evolution and inform knowledge gaps in this area. Research placed in phase 1 establishes links between physical activity and health-related outcomes; phase 2 develops approaches to quantify physical activity behavior; phase 3 identifies factors associated with implementation of physical activity behaviors; phase 4 assesses the effectiveness of interventions to promote activity; and phase 5 disseminates evidence-based recommendations. Peer-reviewed literature was identified by searching PubMed, Google Scholar, and EBSCO-host. We initially identified 287 potential articles. After further review, we excluded 109 articles, leaving 178 included articles. Of these, 75.84% were categorized into phase 1 (n = 135), 10.11% in phase 2 (n = 18), 9.55% into phase 3 (n = 17), 3.37% into phase 4 (n = 6), and 1.12% into phase 5 (n = 2). By applying the behavioral framework to the physical activity literature for people with Parkinson disease, we suggest this area of research is nascent with more than 75% of the literature in phase 1.Level Of Evidence: III. [ABSTRACT FROM AUTHOR]

A variety of NiII complexes with a wide range of electronic and steric properties, bearing picolylimidazolidene ligands (a-g) and Cp (Cp = η5-C5H5; 2a-f ) or Cp* (Cp* = η5- C5Me5; 3a, c, g) groups, have been synthesised and characterised by using NMR spectroscopy and single-crystal X-ray crystallography. The complexes have been used as precatalysts for a wide range of catalytic transformations, which most likely involve a Ni0/NiII catalytic cycle. In particular, the new welldefined 2a, 2c, 3a and 3c complexes have demonstrated great efficiency and versatility towards Suzuki-Miyaura coupling reactions, hydroamination of activated olefins and C-S cross-coupling reactions of aryl halides and thiols under mild conditions. [ABSTRACT FROM AUTHOR]

C−F and C−H bond activation reactions of polyfluoroaromatics at the cyclic (alkyl)(amino)carbene (cAAC) cAACmethyl ( 1) are reported. Studies on the C−F bond activation using the cAAC-stabilized nickel(0) complex [Ni(cAACmethyl)2] ( 2) have shown that 2 does not react with fluorinated arenes. However, these investigations led to the observation of C−F bond cleavage of perfluorinated arenes by the carbene ligand cAACmethyl ( 1) itself. The reaction of 1 with C6F6, C6F5−C6F5, C6F5−CF3, and C5F5N afforded the insertion products of cAAC into one of the C−F bonds of the substrate, that is, the C−F bond activation products (cAACmethyl)F(Arf) (Arf=C6F5 4 a, C6F4−C6F5 4 b, C6F4−CF3 4 c, C5F4N 4 d). These products decompose readily upon heating to 80 °C within a few hours in solution with formation of ionic iminium salts [(cAACmethyl)(Arf)][X] 6 a- d or neutral alkenyl perfluoroaryl imine compounds 7 a- d. The compounds (cAACmethyl)F(Arf) 4 a- d readily transfer fluoride, which has been exemplified by the fluoride transfer of all compounds using BF3 etherate as fluoride acceptor. Fluoride transfer has also been achieved starting from (cAACmethyl)F(C6F4-CF3) ( 4 c) or (cAACmethyl)F(C5F4N) ( 4 d) to other selected substrates such as trimethylchlorosilane, benzoyl chloride and tosyl chloride. Instead of C−F bond activation, insertion of the cAAC into the C−H bond was observed if 1 was treated with the partially fluorinated arenes C6F5H, 1,2,4,5-C6F4H2, 1,3,5-C6F3H3, and 1,3-C6F2H4. The compounds (cAACmethyl)H(Arf) (Arf=C6F5 12 e, 2,3,5,6-C6F4H 12 f, 2,4,6-C6F3H2 12 g and 2,6-C6F2H3 12 h) have been isolated in good yields and have been characterized including X-ray analysis. Fluorobenzene C6FH5 (p Ka ≈37), the least C−H acidic fluoroarene used in this study, does not react. In order to investigate the scope and limitations of this type of cAAC C−H bond activation reaction, cAACmethyl ( 1) was treated with several other reagents of different C−H acidity such as imidazolium salts, imidazoles, esters, and trimethylphosphine. These investigations led to the isolation and characterization of the compounds [(cAACmethyl)H(R2ImMe2)]X ( 13 a,b), (cAACmethyl)H(ImR2) ( 14 a- c), (cAACmethyl)H(CH(COOCH3)2) ( 15 b) and (cAACmethyl)H(CH2-PMe2) ( 16). Deprotonation of [(cAACmethyl)H(Me2ImMe2)][BF4] ( 13 a) at the cAAC carbon atom using KHMDS as a base led to isolation and structural characterization of the cAACmethyl-NHC heterodimer ( 17). [ABSTRACT FROM AUTHOR]

Most nations of the world are undergoing rapid and dramatic population ageing, which presents great socio-economic challenges, as well as opportunities, for individuals, families, governments and societies. The prevailing biomedical strategy for reducing the healthcare impact of population ageing has been 'compression of morbidity' and, more recently, to increase healthspan, both of which seek to extend the healthy period of life and delay the development of chronic diseases and disability until a brief period at the end of life. Indeed, a recently established field within biological ageing research, 'geroscience', is focused on healthspan extension. Superimposed on this background are new attitudes and demand for 'optimal longevity' - living long, but with good health and quality of life. A key obstacle to achieving optimal longevity is the progressive decline in physiological function that occurs with ageing, which causes functional limitations (e.g. reduced mobility) and increases the risk of chronic diseases, disability and mortality. Current efforts to increase healthspan centre on slowing the fundamental biological processes of ageing such as inflammation/oxidative stress, increased senescence, mitochondrial dysfunction, impaired proteostasis and reduced stress resistance. We propose that optimization of physiological function throughout the lifespan should be a major emphasis of any contemporary biomedical policy addressing global ageing. Effective strategies should delay, reduce in magnitude or abolish reductions in function with ageing (primary prevention) and/or improve function or slow further declines in older adults with already impaired function (secondary prevention). Healthy lifestyle practices featuring regular physical activity and ideal energy intake/diet composition represent first-line function-preserving strategies, with pharmacological agents, including existing and new pharmaceuticals and novel 'nutraceutical' compounds, serving as potential complementary approaches. Future research efforts should focus on defining the temporal patterns of functional declines with ageing, identifying the underlying mechanisms and modulatory factors involved, and establishing the most effective lifestyle practices and pharmacological options for maintaining function. Continuing development of effective behavioural approaches for enhancing adherence to healthy ageing practices in diverse populations, and ongoing analysis of the socio-economic costs and benefits of healthspan extension will be important supporting goals. To meet the demands created by rapid population ageing, a new emphasis in physiological geroscience is needed, which will require the collaborative, interdisciplinary efforts of investigators working throughout the translational research continuum from basic science to public health. [ABSTRACT FROM AUTHOR]

Standardized methods for prescribing and monitoring exercise intensity are needed to advance exercise research in Alzheimer's disease ( AD). The purpose of this study was to evaluate the concurrent validity of a modified 1-10 Rating of Perceived Exertion ( RPE) scale against heart rate ( HR) in older adults with mild-to-moderate AD ( N = 8, age 77-87 years). RPE and HR were assessed every 5 min during each exercise session with 3,988 data pairs. Pearson and Spearman correlations and mixed models for correlated data were used for analysis. Results show the correlation between RPE and HR and between RPE and change in HR from resting was −.11 ( SE = .15) and −.31 ( SE = .17), respectively. The proportions of variance explained by RPE overall, RPE within participant, and RPE within session were only 4.0, 5.3, and 6.7%, respectively. We conclude that the modified 1-10 RPE scale did not show concurrent validity to HR, with large between-individual variability. [ABSTRACT FROM AUTHOR]

This paper presents an overview on the experimental investigation of the response of composite materials under multiaxial cyclic loading, starting from the pioneering works in the early 1970s to arrive to the research activities run in these days by the scientific community and concluding with the areas still open. The experimental techniques and sample geometries are compared, illustrating advantages and drawbacks of each solution, also with reference to the outcomes of the research. The influence of the main design parameters are illustrated, taking advantage of experimental results from the extensive investigation carried out in the last years at the University of Padova. Needs of future research are eventually addressed. [ABSTRACT FROM AUTHOR]