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ZusammenfassungWir präsentieren zwei Fallberichte, bei denen in überraschender Weise lesbare Schrift bzw. Zahlen auf dem aspirierten Material nützliche Informationen zu den näheren Umständen der Aspiration lieferten.Im ersten Fall klagte die Patientin nach Benutzung eines Dosieraerosols über Fremdkörpergefühl. Wenige Stunden später wurde das anfangs unbekannte aspirierte Material durch flexible Bronchoskopie geborgen. Mithilfe des Textfragments auf dem Material konnte geschlossen werden, dass es sich um die Verpackungsfolie eines Bonbons handelte, die bei der Aufbewahrung in der Jackentasche der Patientin in das Mundstück des Dosieraerosols gelangt war.Im zweiten Fall traten bei dem Patienten über Jahre rezidivierend Pneumonien auf. Mithilfe der Seriennummer auf dem bronchoskopisch geborgenen Plastikmaterial konnte der genaue Zeitpunkt und Ort der Aspiration ermittelt werden. Der Patient hatte während seiner beruflichen Tätigkeit in einer Autowerkstatt das Plastiketikett eines Ersatzteils aspiriert.

We present two case reports in which, in a surprising way, readable writing or numbers on the aspirated material provided useful information about the more detailed circumstances of the aspiration.In the first case, the patient complained of foreign body sensation after using a metered dose inhaler. A few hours later, the initially unknown aspirated material was recovered by flexible bronchoscopy. With the help of the text fragment on the material, it could be concluded that it was the packaging foil of a candy, which had entered the mouthpiece of the metered dose inhaler while stored in the patient's jacket pocket.In the second case, the patient experienced recurrent pneumonia over a period of years. With the help of the serial number on the bronchoscopically recovered plastic material, the exact time and place of aspiration could be determined. The patient had aspirated the plastic label of a spare part during his occupational activity in a car repair shop.Wir präsentieren zwei Fallberichte, bei denen in überraschender Weise lesbare Schrift bzw. Zahlen auf dem aspirierten Material nützliche Informationen zu den näheren Umständen der Aspiration lieferten.Im ersten Fall klagte die Patientin nach Benutzung eines Dosieraerosols über Fremdkörpergefühl. Wenige Stunden später wurde das anfangs unbekannte aspirierte Material durch flexible Bronchoskopie geborgen. Mithilfe des Textfragments auf dem Material konnte geschlossen werden, dass es sich um die Verpackungsfolie eines Bonbons handelte, die bei der Aufbewahrung in der Jackentasche der Patientin in das Mundstück des Dosieraerosols gelangt war.Im zweiten Fall traten bei dem Patienten über Jahre rezidivierend Pneumonien auf. Mithilfe der Seriennummer auf dem bronchoskopisch geborgenen Plastikmaterial konnte der genaue Zeitpunkt und Ort der Aspiration ermittelt werden. Der Patient hatte während seiner beruflichen Tätigkeit in einer Autowerkstatt das Plastiketikett eines Ersatzteils aspiriert.

Termites are responsible for ∼1 to 3% of global methane (CH(4)) emissions. However, estimates of global termite CH(4) emissions span two orders of magnitude, suggesting that fundamental knowledge of CH(4) turnover processes in termite colonies is missing. In particular, there is little reliable information on the extent and location of microbial CH(4) oxidation in termite mounds. Here, we use a one-box model to unify three independent field methods—a gas-tracer test, an inhibitor approach, and a stable-isotope technique—and quantify CH(4) production, oxidation, and transport in three North Australian termite species with different feeding habits and mound architectures. We present systematic in situ evidence of widespread CH(4) oxidation in termite mounds, with 20 to 80% of termite-produced CH(4) being mitigated before emission to the atmosphere. Furthermore, closing the CH(4) mass balance in mounds allows us to estimate in situ termite biomass from CH(4) turnover, with mean biomass ranging between 22 and 86 g of termites per kilogram of mound for the three species. Field tests with excavated mounds show that the predominant location of CH(4) oxidation is either in the mound material or the soil beneath and is related to species-specific mound porosities. Regardless of termite species, however, our data and model suggest that the fraction of oxidized CH(4) (f(ox)) remains well buffered due to links among consumption, oxidation, and transport processes via mound CH(4) concentration. The mean f(ox) of 0.50 ± 0.11 (95% CI) from in situ measurements therefore presents a valid oxidation factor for future global estimates of termite CH(4) emissions.

Animals, such as termites, have largely been overlooked as global-scale drivers of biogeochemical cycles1,2, despite site-specific findings3,4. Deadwood turnover, an important component of the carbon cycle, is driven by multiple decay agents. Studies have focused on temperate systems5,6, where microbes dominate decay7. Microbial decay is sensitive to temperature, typically doubling per 10°C increase (decay effective Q10 = ~2)8–10. Termites are important decayers in tropical systems3,11–13 and differ from microbes in their population dynamics, dispersal, and substrate discovery14–16, meaning their climate sensitivities also differ. Using a network of 133 sites spanning 6 continents, we report the first global field-based quantification of temperature and precipitation sensitivities for termites and microbes, providing novel understandings of their response to changing climates. Temperature sensitivity of microbial decay was within previous estimates. Termite discovery and consumption were both much more sensitive to temperature (decay effective Q10 = 6.53), leading to striking differences in deadwood turnover in areas with and without termites. Termite impacts were greatest in tropical seasonal forests and savannas and subtropical deserts. With tropicalization17 (i.e., warming shifts to a tropical climate), the termite contribution to global wood decay will increase as more of the earth’s surface becomes accessible to termites. Acknowledgements. For materials, field, and lab assistance, we thank the Australian Landscape Trust Team, Juan Martínez de Aragón, Eric Roy, Hugh Wilson, Kylie Brice, Bethanie Coleman, Brendan Delroy, Coline Deveautour, Suzanne Donn, Generci Assis Neves, Ricardo Marques Barreiros, Ricardo Marques Barreiros, Generci Assis Neves from Resineves Agroflorestal company, Alfred Lochner, Pousada Vale do Céu, Humberto Robles, María M. Rivera, and Grant Kirker. Steve Allison and Tom Crowther provided comments on the manuscript and Abbey Yatsko helped with figure and manuscript formatting. Funding for this work was provided by US National Science Foundation (DEB-1655759, 2149151, 1713502, 1713435, 1647502, 1546686, 1831952), George Washington University, USDA Forest Service, Centre College Faculty Development Funds, Australia Terrestrial Ecosystem Research Network (TERN) National Collaborative Research Infrastructure Strategy (NCRIS), Royal Society-FCDO Africa Capacity Building Initiative, New Phytologist Foundation, Fondecyt grant:1160329, Coordenação de Aperfeiçoamento de Pessoal de Nível Superior, Brasil (CAPES), Department of Ecology and Conservation of the Federal University of Lavras, CNPq, FAPEMIG, Australian Academy of Science 2017 Thomas Davies Research Grant, Australian Research Council (DP160103765), UK National Environment Research Council (NE/L000016/1), Fundação de Amparo à Pesquisa do Estado de São Paulo, Brazil (NERC - FAPESP)19/07773-1, Environment Research and Technology Development Fund (ERTDF; JPMEERF15S11420) of the Environmental Restoration and Conservation Agency (ERCA) of Japan, COLCIENCIAS (No. FP44842-046-2017), Spanish Government (grant PID2019-110521GB-I00), Catalan Government (grant SGR 2017-1005), Fundación Ramón Areces (grant ELEMENTAL-CLIMATE), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Agencia Nacional de Promoción Científica y Tecnológica (ANPCyT) PICT 2019- 2472, National Agency for the Promotion of Research, Technological Development and Innovation, Scientific and Technological Research Project 2018-01561 (PICT 2018- 01561), iDiv German Research Foundation (DFG– FZT 118, 202548816), European Research Council (ERC), European Union's Horizon 2020 research and innovation program (grant agreement no. 677232).

Chronic foot and leg ulcers are a common health problem worldwide. A mainstay of chronic ulcer therapy is sharp mechanical wound debridement requiring potent analgesia. In this prospective, controlled, single-centre, crossover design study, patients were assigned to either the administration of topical analgesia with 5% lidocaine/prilocaine cream or the inhalation of an analgesic 50% N2 O/O2 gas premix. Primary outcome parameter was level of pain at maximum wound depth during debridement as measured by a visual analogue scale. Secondary outcomes included level of pain after debridement, overall duration of treatment session, duration and completeness of debridement, and the patient's subjective perception of analgesic quality during debridement. Pain level increased from 0·60/0·94 (first/second debridement; baseline) to 1·76/2·50 (debridement) with 5% lidocaine/prilocaine and from 1·00/1·35 (baseline) to 3·95/3·29 (debridement) with 50% N2 O/O2 gas premix. Patient satisfaction was 90·48%/94·44% (first/second debridement) with topical 5% lidocaine/prilocaine analgesia and 90·48%/76·47% with the inhalation of 50% N2 O/O2 gas premix. Debridement was completed in a significantly higher percentage of 85·71%/88·89% (first/second debridement) with 5% lidocaine/prilocaine than with 50% N2 O/O2 gas premix (42·86%/58·82%) (odds ratio 6·7; P = 0·001). This study provides sound evidence that analgesia with topically administered 5% lidocaine/prilocaine cream is superior to the use of inhaled 50% N2 O/O2 gas premix in chronic leg ulcer debridement.

Monocationic bis(hydrocarbyl)yttrium complexes [YR2(THF)2][A] (R = CH2SiMe3, CH2C6H4-o-NMe2; A = weakly coordinating anion) underwent hydrogenolysis using dihydrogen or phenylsilane to give a mixture of polynuclear solvent-stabilized dihydride cations [YH2(THF)2]n[A]n. The mixture composition as well as the nuclearity n depended on the starting material, solvent, and reaction conditions. NMR spectroscopic data in solution and X-ray diffraction data suggested that the main product was tetranuclear, although conclusive structural data were not obtained. DFT calculations supported a closo-type tetrahedral [YH2(THF)2]44+ core. The hydridic character of these cations was revealed by their reaction with benzophenone to give the bis(diphenylmethoxy) cation [Y(OCHPh2)2(THF)4][AlR4]. The reaction of this cluster with the (NNNN)-type macrocycle Me4TACD under dihydrogen gave the dinuclear tetrahydride dication with quadruply bridging hydride ligands, [Y2(μ-H)4(Me4TACD)2][A]2, analogous to the previously characterized lutetium derivative. NH-acidic (Me3TACD)H gave the dinuclear dihydride dication [Y2(μ-H)2(Me3TACD)2(THF)2][A]2.

Im Rahmen der Konzernweiten globalen Vereinheitlichung des Produktportfolios entwickelt die Daimler AG eine neue Motorenbaureihe — die „Heavy Duty Engine Platform” fur den Einsatz in schweren Nutzfahrzeugen. Mit der Vorstellung des Detroit Diesel DD15 wurde aktuell der erste Motor dieser Motorenfamilie mit 14,8 l Hubraum auf dem nordamerikanischen Markt eingefuhrt. Weitere Varianten dieser Plattform werden mit den Hubraumen 15,6 l, 12,8 l sowie 10,6 l folgen. Diese Motoren halten dann Schritt fur Schritt Einzug in alle Lkw der Daimler AG.

As part of the group-wide global standardization of the product portfolio, Daimler AG is developing a new engine series — the Heavy Duty Engine Platform (HDEP) for use in heavy commercial vehicles. With the unveiling of the Detroit Diesel DD15, the first engine in this family, with a capacity of 14.8 l, was introduced on the North American market. Additional variations of this platform will follow with displacements of 15.6 l, 12.8 l and 10.6 l. These engines will then be introduced gradually in all Daimler AG trucks.

Due to their ploidy levels, their morphological and anatomical characters and their distribution the central alpine Festuca stricta subsp. bauzanina (2n = 8x = 56) and Festuca ovina var. guinochetii (2n = 10x = 70), both belonging to the Festuca valesiaca group, are raised to the specific level. As a new subspecies Festuca bauzanina subsp. rhaetica is described here. The taxa of the polyploid Festuca valesiaca group are morphologically, anatomically and chorologically characterised and an identification key for these taxa in the central Alps is presented.

We have prepared tungsten bispyrrolyl (Pyr) or bis-2,5-dimethylpyrrolyl (Me2Pyr) complexes W(NAr)(CHCMe2Ph)(η1-Pyr)2(DME) (1), W(NAr)(CHCMe2Ph)(η1-Me2Pyr)(η5-Me2Pyr) (2), W(NArCl)(CHCMe3)(η1-Pyr)2(DME) (3b), and W(NArCl)(CHCMe3)(η1-Me2Pyr)(η5-Me2Pyr) (4) (Ar = 2,6-diisopropylphenyl, ArCl = 2,6-dichlorophenyl) in excellent yields by treating the appropriate W(NR)(CHCMe2R‘)(OTf)2(DME) species with LiPyr or LiMe2Pyr. Compounds 2 and 4 react with ethylene slowly to yield stable methylene complexes, W(NAr)(CH2)(η1-Me2Pyr)(η5-Me2Pyr) (5) and W(NArCl)(CH2)(η1-Me2Pyr)(η5-Me2Pyr) (6). In contrast, treatment of what is believed to be a fortuitous 1:1 mixture of 3b and [W(NArCl)(CHCMe3)(η1-Pyr)2][W(NArCl)(CHCMe3)(η1-Pyr)(η5-Pyr)] with ethylene leads to formation of [W(μ-NArCl)(η1-Pyr)2]2 (7) in moderate (54%) yield. Compounds 2 and 4 react with [HNMe2Ph][B(ArF)4] (ArF = 3,5-(CF3)2C6H3) in dichloromethane to yield cationic species that contain one η5-Me2Pyr ligand and one 2,5-dimethylpyrrolenine ligand formed through...

Tungsten alkylidene complexes that contain the 2,6-dichlorophenylimido ligand (NArCl), W(NArCl)(CHCMe3)(ORF6)2 and W(NArCl)(CHCMe3)(Biphen)(THP) (ORF6 = OCMe(CF3)2; Biphen2- = 3,3‘-di-t-Bu-5,5‘,6,6‘-tetramethyl-1,1‘-biphenyl-2,2‘-diolate; THP = tetrahydropyran), have been prepared from W(NArCl)(CHCMe3)(OSO2CF3)2(dme). Reaction of W(NArCl)(CHCMe3)(ORF6)2 with excess ethylene gave the tungstacyclobutane complex W(NArCl)(ORF6)2(C3H6), while reaction of W(NArCl)(CHCMe3)(ORF6)2 with internal olefins gave the dimer, [W(μ-NArCl)(ORF6)2]2. W(NArCl)(CHCMe3)(Biphen)(THP) reacted with excess ethylene to give W(NArCl)(Biphen)(C3H6), which yielded W(NArCl)(Biphen)(C2H4)(THF) upon addition of THF. The tungstacyclopentane complex, W(NArCl)(Biphen)(C4H8), was formed upon treatment of W(NArCl)(Biphen)(C2H4)(THF) with ethylene. W(NArCl)(Biphen)(C3H6) decomposed to yield (inter alia) the dimeric, heterochiral methylidene complex, [W(NArCl)(Biphen)(μ-CH2)]2, which decomposed further to yield homochiral [W(NArCl)(Biphen)]2(μ-...

Rare-earth metal alkyl tri(tert-butoxy)silanolate complexes [Ln{mu,eta2-OSi(O(t)Bu)3}(CH2SiMe3)2]2 (Ln = Y (1), Tb (2), Lu (3)) were prepared via protonolysis of the appropriate tris(alkyl) complex [Ln(CH2SiMe3)3(thf)2] with tri(tert-butoxy)silanol in pentane. Crystal structure analysis revealed a dinuclear structure for with square pyramidal geometry at the yttrium centre. The silanolate ligand coordinates in an eta2-bridging coordination mode giving a 4-rung truncated ladder and non-crystallographic inversion centre. Addition of two equiv. of 12-crown-4 to a pentane solution of 1 or 3 respectively gave [Ln{OSi(O(t)Bu)(3)}(CH2SiMe3)2(12-crown-4)].12-crown-4 (Ln = Y (4), Lu (5)). Crystal structure analysis of 5 showed a slightly distorted octahedral geometry at the lutetium centre. The silanolate ligand adopts an eta(1)-terminal coordination mode, whilst the crown ether unit coordinates in an unusual kappa3-fashion. Reaction of 1-3 with [NEt3H]+[BPh4]- in thf yielded the cationic derivatives [Ln{OSi(O(t)Bu)3}(CH2SiMe3)(thf)4]+[BPh4]- (Ln = Y (6), Tb (7) and Lu (8)); coordination of crown ether led to compounds of the form [Ln{OSi(O(t)Bu)3}(CH2SiMe3)(L)(thf)n]+[BPh4]- (Ln = Y, Lu, L = 12-crown-4, n = 1 (9,10); Ln = Y, Lu, L = 15-crown-5, n = 0 (11,12)). Reaction of 1 with [NMe2PhH]+[B(C6F5)4]-, [Al(CH2SiMe3)3] or BPh3 in thf gave the ion pairs [Y{OSi(O(t)Bu)3}(CH2SiMe3)(thf)4]+[A]- ([A]- = [B(C6F5)4]- (13), [Al(CH2SiMe3)4]- (14), [BPh3(CH2SiMe3)]- (15)), whilst two equiv. [NMe2PhH]+[BPh4]- with 1 in thf produced the dicationic ion triple [Y{OSi(O(t)Bu)3}(thf)6]2+[BPh4]-2 (16). Crystal structure analysis revealed that 16 is mononuclear with pentagonal bipyramidal geometry at the yttrium centre. The silanolate ligand coordinates in an eta(1)-terminal fashion. All diamagnetic compounds have been characterized by NMR spectroscopy. 1, 3, 4, 6 and 13 were tested as olefin hydrosilylation pre-catalysts with a variety of substrates; 1 was found to be highly active in 1-decene hydrosilylation.

Cationic alkyl complexes of the rare-earth metals [LnRm(L)n](3–m)+ (R=alkyl; m=1, 2; L=Lewis base) were virtually unknown species until recently. Because of their increased Lewis acidity/electrophilicity they should have considerable potential as homogeneous catalysts in olefin polymerization and in organic transformations. They can be generated by treating the neutral rare-earth metal precursors containing at least two alkyl groups R with suitable Lewis or Bronsted acids in the presence of weakly coordinating anions. Not only monocationic but also dicationic alkyl derivatives have been shown to be accessible. In the context of modeling homogeneous ethylene polymerization using a mixture consisting of LnR3/AlR3/[NMe2HPh][B(C6F5)4], such dications were discovered. Some thermally robust examples of mono- and dicationic alkyl complexes have been structurally characterized as solvent-separated ion pairs. Neutral and monoanionic macrocycles such as crown ethers or aza-crown ethers as well as amidinato, β-diketiminato, and substituted cyclopentadienyl ligands are suitable ancillary ligands to stabilize the cationic alkyl fragments.

Rare-earth metal complexes of the type [Ln{η5:η1-C5Me4SiMe2(C4H3O-2)}(CH2SiMe3)2(THF)] (Ln = Y, Lu) were prepared by σ-bond metathesis of [Ln(CH2SiMe3)3(THF)2] with the 2-furyl-functionalized tetramethylcyclopentadiene (C5Me4H)SiMe2(C4H3O-2) and isolated as colorless crystals. Single-crystal X-ray structure analysis of the lutetium complex confirmed the coordination of the furyl group and THF to give a molecule of trigonal bipyramidal geometry with the oxygen donor atoms in the apical positions. The lability of the oxygen donor atoms results in fluxional behavior. Reaction with triphenylborane in THF gave thermally robust mono(alkyl) cations [Ln{η5:η1-C5Me4SiMe2(C4H3O-2)}(CH2SiMe3)(THF)n]+. Unexpectedly, the reaction of [Ln(CH2SiMe3)3(THF)2] with the 5-methylfuryl-functionalized tetramethylcyclopentadiene (C5Me4H)SiMe2{(C4H2MeO-5)-2} gave yne-enolate complexes [Ln{η5:η1-C5Me4SiMe2C⋮CCHCMeO)}(CH2SiMe3)]2 under elimination of 2 equiv of SiMe4. Single-crystal X-ray structure analysis of the yttrium complex r...

The dimeric rare-earth hydrides [Ln(η^5:η^1-C_5Me_4SiMe_2NCMe_3)(THF)(μ-H)]_2 (Ln = Y, Yb) react with excess α-olefin H_2C ═ CHR (R = Et, ^nPr, ^nBu) in a 1,2-insertion to give the series of THF-free dimeric n-alkyl complexes [Ln(η^5:η^1-C_5Me_4SiMe_2NCMe_3)(μ-CH_2CH_2R)]_2 as isolable crystals. Single-crystal X-ray diffraction studies on the five derivatives [Y(η^5:η^1-C_5Me_4SiMe_2NCMe_2R‘)(μ-CH_2CH_2R)]_2 (R‘ = Me, R = Et, ^nBu; R‘ = Et, R = Et, ^nPr) and [Yb(η^5:η^1-C_5Me_4SiMe_2NCMe_3)(μ-CH_2CH_2^nBu)]_2 revealed that the centrosymmetric dimeric complexes consist of two trans-arranged [Ln(η^5:η^1-C_5Me_4SiMe_2NCMe_2R‘)] fragments connected by two μ-alkyl ligands. Most strikingly, there is an agostic interaction of the n-alkyl groups' β-CH_2 hydrogen atoms with the formally 12-electron lanthanide metal center. Variable-temperature NMR spectroscopic data suggest a fluxional process that interconverts the diastereotopic protons of the α-CH_2 group and a dynamic β-agostic interaction. Addition of >10 equiv of THF per yttrium to a solution of [Y(η^5:η^1-C_5Me_4SiMe_2NCMe_3)(μ-CH_2CH_2Et)]_2 results in the formation of the highly reactive, nonisolable, monomeric THF adduct [Y(η^5:η^1-C_5Me_4SiMe_2NCMe_3)(CH_2CH_2Et)(THF)]. Reaction of 1,2-dimethoxyethane (DME) with [Y(η^5:η^1-C_5Me_4SiMe_2NCMe_3)(μ-CH_2CH_2Et)]_2 forms the crystalline compound [Y(η^5:η^1-C_5Me_4SiMe_2NCMe_3)(CH_2CH_2Et)(DME)] with a terminal n-butyl group that contains a slightly distorted α-carbon atom according to a crystallographic study. α-Olefins having two or more substituents on the γ-carbon do not react with the hydride complexes. The role of these n-alkyl complexes in the controlled polymerization of styrene is discussed.

In order to understand the nature of the putative cationic 12-electron species [M(η 5 :η 1 -C 5 R 4 SiMe 2 NR′)R″] + of titanium catalysts supported by a linked amido-cyclopentadienyl ligand, several derivatives with different cyclopentadienyl C 5 R 4 and amido substituents R′ were studied systematically. The use of tridentate variants (C 5 R 4 SiMe 2 NCH 2 CH 2 X) 2− (C 5 R 4 =C 5 Me 4 , C 5 H 4 , C 5 H 3 t Bu ; X=OMe, SMe, NMe 2 ) allowed the NMR spectroscopic observation of the titanium benzyl cations [Ti(η 5 :η 1 -C 5 Me 4 SiMe 2 NCH 2 CH 2 X)(CH 2 Ph)] + . Isoelectronic neutral rare earth metal complexes [Ln(η 5 :η 1 -C 5 R 4 SiMe 2 NR′)R″] can be expected to be active for polymerization. To arrive at neutral 12-electron hydride and alkyl species of the rare earth metals, we employed a lanthanide tris(alkyl) complex [Ln(CH 2 SiMe 3 ) 3 (THF) 2 ] (Ln=Y, Lu, Yb, Er, Tb), which allows the facile synthesis of the linked amido-cyclopentadienyl complex [Ln(η 5 :η 1 -C 5 Me 4 SiMe 2 NCMe 3 )(CH 2 SiMe 3 )(THF)]. Hydrogenolysis of the linked amido-cyclopentadienyl alkyl complex leads to the dimeric hydrido complex [Ln(η 5 :η 1 -C 5 Me 4 SiMe 2 NCMe 3 )(THF)(μ-H)] 2 . These complexes are single-site, single-component catalysts for the polymerization of ethylene and a variety of polar monomers such as acrylates and acrylonitrile. Nonpolar monomers such as α-olefins and styrene, in contrast, give isolable mono-insertion products which allow detailed studies of the initiation process.

I. Introduction 1953II. Overview of Synthesis, Structure, and Properties 1954A. Synthetic Methods 1954B. Ligands and Structures 1955III. Halo Complexes 1956A. General 1956B. Divalent Halo Complexes 1956C. Trivalent Halo Complexes 1957IV. Chalcogenido Complexes 1958A. General 1958B. Divalent Chalcogenido Complexes 1958C. Trivalent Chalcogenido Complexes 1959V. Pnicogenido Complexes 1960A. General 1960B. Divalent Amido and Phosphido Complexes 1960C. Trivalent Pnicogenido Complexes 19611. Bis(amido) Complexes 19612. Mixed Halo and Chalcogenido Complexes 1962VI. Hydrocarbyl and Silyl Complexes 1963A. General 1963B. Divalent Complexes 19631. Metallacarbaboranes 19632. Bimetallic Naphthalene Complexes 19643. Silyl Complexes 1964C. Bis(Hydrocarbyls) 19641. Bis(alkyl), Bis(aryl), and Anionic Tris(alkyl)Complexes19642. Allyl and Anionic Tris(allyl) Complexes 19653. Metallacyclopentenes 19654. Metallacarbaboranes 19655. Fullerides 1966D. Hydrocarbyl Complexes with Rare-EarthMetal to Chlorine, Oxygen, and NitrogenBonds19661. Aryloxo, Silylamido, and AmidinatoComplexes19662. Linked Pnicogenido CyclopentadienylComplexes1966VII. Hydrido Complexes 1968A. General 1968B. Complexes with a [Ln(

The reaction of the half-sandwich alkyl complex [Y(η5:η1-C5Me4SiMe2NCMe3)(CH2SiMe3)(THF)] with furan and thiophene gives metalation products [Y(η5:η1-C5Me4SiMe2NCMe3)(μ-2-C4H3X)]2 (X=O, S) which are sparingly soluble in hydrocarbons due to the dimeric structure. Single crystal X-ray structure analysis of the 2-thienyl complex confirms a six-membered core with bridging sulfur atoms and trans-disposed amido-tetramethylcyclopentadienyl ligands. In contrast to THF and pyridine, 1,2-dimethoxyethane (DME) forms isolable, crystalline adducts [Y(η5:η1-C5Me4SiMe2NCMe3)(2-C4H3X)(DME)]. Single crystal X-ray structure analysis of the 2-furyl derivative shows a four-legged piano stool configuration. The reaction of [Y(η5:η1-C5Me4SiMe2NCMe3)(CH2SiMe3)(THF)] with excess DME gives the isolable, five-coordinate complex [Y(η5:η1-C5Me4SiMe2NCMe3)(CH2SiMe3)(DME)] that does not react with furan or thiophene, indicating an associative mechanism. [Y(η5:η1-C5Me4SiMe2NCMe3)(CH2SiMe3)(THF)] reacts with pyrrole to give the sparingly soluble pyrrolide that can be studied by crystallography as a DME adduct [Y(η5:η1-C5Me4SiMe2NCMe3)(η1-κN-C4H4N)(DME)]. The reaction of [Y(η5:η1-C5Me4CH2SiMe2NCMe3)(CH2SiMe3)(THF)] that contains the longer CH2SiMe2-bridge reacts with furan to a mixture of a hydrocarbon-soluble dimer and the labile THF adduct, whilst the reaction with thiophene results in the selective formation of the monomeric [Y(η5:η1-C5Me4CH2SiMe2NCMe3)(2-C4H3S)(THF)] which was characterized by crystallography.

The synthesis of rare earth metal half-sandwich hydrido complexes [Ln (h5:h1-C5Me 4SiMe2NCMe3) (THF) (µ-H) ] 2 (Ln = Y, Lu) through s-bond metathesis of the easily accessible alkyl complexes [Ln (h5:h1-C5Me 4SiMe2NCMe3) (CH2 SiMe3) (THF) ] was developed. The dimeric yttrium hydrido complexes are highly fluxional, and a monomer-dimer equilibrium is present. They were tested as single-site, single-component catalysts for the polymerization of ethylene and styrene, as well as alkyl acrylate and acrylonitrile. The hydrido complexes polymerize ethylene slowly and form isolable mono (insertion) products with styrene. The yttrium n-alkyl complexes [Y (h5:h1-C5Me 4SiMe2NCMe3) (R) (THF) ] [R = (CH2) nCH3, n = 3-9], prepared by the mono (insertion) of a-olefins, initiate polymerization in a relatively controlled manner. Thus, styrene was polymerized by the n-alkyl complex to give atactic polystyrenes with somewhat enriched syndiotacticities.

Dimeric hydrido complexes of lutetium, ytterbium, and yttrium containing a linked amido−cyclopentadienyl ligand, [Ln(η5:η1-C5Me4SiMe2NCMe2R)(L)(μ-H)]2 (Ln = Lu, Yb, Y; R = Me, Et; L = THF, PMe3), w...

Misunderstandings have occurred regarding the conclusions of the paper by S. Arndt, W. Dappen and A. Nayfonov 1998, ApJ 498, 349. At occasions, its results were interpreted as if it had shown basic flaws in the general theory of dynamical screening. The aim of this comment is to emphasize in which connection the conclusions of the paper have to be understood in order to avoid misinterpretations.

The activation of pyridine by the dicationic yttrium methyl complex [YMe(THF)6]2+[BPh4]-2 to give the structurally characterized cationic rare-earth metal η2-pyridyl complex [Y{η2-(C,N)-C5H4N}(C5H5N)6]2+[BPh4]-2 is reported. The pyridyl complex adopts a pentagonal bipyramidal coordination geometry with the pyridyl ligand in the axial position; kinetic data demonstrate that this complex forms via the formation of the substitution product [YMe(C5H5N)6]2+[BPh4]-2.

A neural network which models multistable perception is presented. The network consists of sensor and inner neurons. The dynamics is established by a stochastic neuronal dynamics, a formal Hebb-type coupling dynamics and a resource mechanism that corresponds to saturation effects in perception. From this a system of coupled differential equations is derived and analyzed. Single stimuli are bound to exactly one percept, even in ambiguous situations where multistability occurs. The network exhibits discontinuous as well as continuous phase transitions and models various empirical findings, including the percepts of succession, alternative motion and simultaneity; the percept of oscillation is explained by oscillating percepts at a continuous phase transition.

I. Introduction 1953II. Overview of Synthesis, Structure, and Properties 1954A. Synthetic Methods 1954B. Ligands and Structures 1955III. Halo Complexes 1956A. General 1956B. Divalent Halo Complexes 1956C. Trivalent Halo Complexes 1957IV. Chalcogenido Complexes 1958A. General 1958B. Divalent Chalcogenido Complexes 1958C. Trivalent Chalcogenido Complexes 1959V. Pnicogenido Complexes 1960A. General 1960B. Divalent Amido and Phosphido Complexes 1960C. Trivalent Pnicogenido Complexes 19611. Bis(amido) Complexes 19612. Mixed Halo and Chalcogenido Complexes 1962VI. Hydrocarbyl and Silyl Complexes 1963A. General 1963B. Divalent Complexes 19631. Metallacarbaboranes 19632. Bimetallic Naphthalene Complexes 19643. Silyl Complexes 1964C. Bis(Hydrocarbyls) 19641. Bis(alkyl), Bis(aryl), and Anionic Tris(alkyl)Complexes19642. Allyl and Anionic Tris(allyl) Complexes 19653. Metallacyclopentenes 19654. Metallacarbaboranes 19655. Fullerides 1966D. Hydrocarbyl Complexes with Rare-EarthMetal to Chlorine, Oxygen, and NitrogenBonds19661. Aryloxo, Silylamido, and AmidinatoComplexes19662. Linked Pnicogenido CyclopentadienylComplexes1966VII. Hydrido Complexes 1968A. General 1968B. Complexes with a [Ln(

Nicht immer ist der Wille des Erblassers aus einer letztwilligen Verfugung eindeutig zu erkennen. Haufig lasst die Formulierung eines Testaments Raum fur verschiedene Interpretationsmoglichkeiten und der Wille des Erblassers ist daher zweifelhaft. In diesem Fall muss das Testament ausgelegt werden.

Unter bestimmten Voraussetzungen konnen Testamente und sonstige Verfugungen von Todes wegen angefochten werden. Anfechtungsberechtigt sind diejenigen, die durch den Fortfall der angefochtenen Verfugung einen Vorteil haben wurden, und – im Ausnahmefall – auch der Verfugende selbst.

Der Gesetzgeber tragt der besonderen Situation Minderjahriger im Erbrecht in zweifacher Weise Rechnung: Zum einen berucksichtigt er, dass Minderjahrige auch schon vor Eintritt der Volljahrigkeit in der Lage sein konnen, ihren letzten Willen zu formulieren, daher verlagert er den Zeitpunkt, zu dem Minderjahrige ein Testament wirksam errichten konnen, vor den Eintritt der Volljahrigkeit. Zum anderen berucksichtigt der Gesetzgeber die besondere Schutzbedurftigkeit Minderjahriger und hat durch das Minderjahrigenhaftungsbeschrankungsgesetz vom 25.08.1998 Regelungen zur Moglichkeit der Haftungsbeschrankung von minderjahrigen Erben im Erbfall vorgesehen.

Eine Schenkung, die mit der Bedingung verknupft wird, dass der Beschenkte den Schenker uberlebt, wird als „Schenkungsversprechen von Todes wegen“ bezeichnet.

Das deutsche Erbrecht wird von einigen Grundprinzipien beherrscht. Ihre Kenntnis erleichtert das Verstandnis der Einzelregelungen und damit letztlich den Umgang mit dem Erbrecht. Sie sollen daher zunachst erlautert werden.

Testamentarische Anordnungen oder Verfugungen in Erbvertragen konnen von vorneherein unwirksam sein oder dies auch zukunftig werden.

Im Unterschied zu Kapitalgesellschaften (AG,GmbH,KGaA) sind Anteile an Personengesellschaften nicht ohne weiteres vererblich. Der Grund hierfur besteht in dem strukturellen Unterschied zwischen den beiden Gesellschaftstypen. Wahrend die Kapitalgesellschaft weitgehend unabhangig von den Gesellschaftern operieren kann – je nach Rechtsform mehr oder weniger ausgepragt – und die kapitalistische Beteiligung des Gesellschafters im Vordergrund der Beteiligung steht, ist die Personengesellschaft – jedenfalls im Grundsatz – durch die personliche Verbundenheit der Gesellschafter gepragt, sichtbar an dem nach dem Grundtypus vorgesehenen personlichen Einsatz und der personlichen Haftung der Gesellschafter. Dies hat den Gesetzgeber veranlasst, die Anteile an einer Personengesellschaft – anders als die der Kapitalgesellschaft – nicht von vorneherein fur vererblich zu erklaren. Gleichwohl gibt es – je nach Form der Personengesellschaft – Unterschiede, die auf den Grad der personlichen Verbundenheit und der personlichen Haftung zuruckzufuhren sind.

Nicht immer ist eine Erbschaft willkommen. Es sind Falle denkbar, in denen der Bedachte von dem Verstorbenen keine Vermogenswerte ubernehmen will – etwa aus personlichen oder aus steuerlichen Grunden – z. B. zur Rettung steuerlicher Freibetrage bei den Kindern. Weitaus haufiger sind indes Falle, in denen die Annahme der Erbschaft fur den Bedachten wirtschaftlich nachteilig ware. Das sind Falle, in denen der Nachlass neben Vermogenswerten auch finanzielle Verbindlichkeiten oder sonstige Verpflichtungen beinhaltet, die den Wert des Aktivvermogens unter Umstanden sogar ubersteigen. In diesen Fallen muss es dem Erben moglich sein, seine Erbenstellung zu beseitigen.

In einem Testament oder Erbvertrag kann der Erblasser die unterschiedlichsten Regelungen treffen, um seine Vermogensnachfolge individuell und personlich zu regeln. Solche individuellen Regelungen gehen der gesetzlichen Erbfolge vor. Mit dem Prinzip der Testierfreiheit hat sich der Gesetzgeber entschieden, dem Willen des Einzelnen Vorrang vor den Anordnungen des Gesetzgebers zu geben. Inhaltliche Grenzen ergeben sich aus dem im Erbrecht geltenden Typenzwang (vgl.§ 1 E.), aus dem Verbot sittenwidriger und gesetzeswidriger Verfugungen (§§ 134, 138 BGB) sowie aus dem zumindest im Grundsatz nicht entziehbaren Pflichtteilsrechten der nachsten Angehorigen.

Synthesis, structure, and reactivity of two families of rare-earth metal complexes containing discrete methyl cations [LnMe(2-x)(thf)n]((1+x)+) (x = 0, 1; thf = tetrahydrofuran) have been studied. As a synthetic equivalent for the elusive trimethyl complex [LnMe3], lithium methylates of the approximate composition [Li3LnMe6(thf)n] were prepared by treating rare-earth metal trichlorides [LnCl3(thf)n] with 6 equiv of methyllithium in diethyl ether. Heteronuclear complexes of the formula [Li3Ln2Me9L(n)] (Ln = Sc, Y, Tb; L = Et2O, thf) were isolated by crystallization from diethyl ether. Single crystal X-ray diffraction studies revealed a heterometallic aggregate of composition [Li3Ln2Me9(thf)n(Et2O)m] with a [LiLn2Me9](2-) core (Ln = Sc, Y, Tb). When tris(tetramethylaluminate) [Ln(AlMe4)3] (Ln = Y, Lu) was reacted with less than 1 equiv of [NR3H][BPh4], the dimethyl cations [LnMe2(thf)n][BPh4] were obtained. The coordination number as well as cis/trans isomer preference was studied by crystallographic and computational methods. Dicationic methyl complexes of the rare-earth metals of the formula [LnMe(thf)n][BAr4]2 (Ln = Sc, Y, La-Nd, Sm, Gd-Lu; Ar = Ph, C6H4F-4) were synthesized, by protonolysis of either the ate complex [Li3LnMe6(thf)n] (Ln = Sc, Y, Gd-Lu) or the tris(tetramethylaluminate) [Ln(AlMe4)3] (Ln = La-Nd, Sm, Dy, Gd) with ammonium borates [NR3H][BAr4] in thf. The number of coordinated thf ligands varied from n = 5 (Ln = Sc, Tm) to n = 6 (Ln = La, Y, Sm, Dy, Ho). The configuration of representative examples was determined by X-ray diffraction studies and confirmed by density-functional theory calculations. The highly polarized bonding between the methyl group and the rare-earth metal center results in the reactivity pattern dominated by the carbanionic character and the pronounced Lewis acidity: The dicationic methyl complex [YMe(thf)6](2+) inserted benzophenone as an electrophile to give the alkoxy complex [Y(OCMePh2)(thf)5](2+). Nucleophilic addition of the soft anion X(-) (X(-) = I(-), BH4(-)) led to the monocationic methyl complexes [YMe(X)(thf)5](+).