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Recent research has shown that there exists large heterogeneity in car-following behaviour such that different car-following models best describe different drivers' behaviour. A literature review reveals that current approaches to calibrate and compare different models for one driver do not take the complexity of the models into account or are only able to compare a specific set of models. This contribution applies Bayesian techniques to the calibration of car-following models. The Bayesian framework promotes models that fit the data well but punishes models with a high complexity, resulting in a measure called the evidence. This evidence quantifies how probable each model is to be the model that best describes the car-following behaviour of a single driver. It can be computed for any car-following model. When considered over multiple drivers, the evidences can be used to describe the heterogeneity of the driving population. In an experiment seven different car-following models are calibrated and compared using a data set that was collected with a helicopter. The results indicate that multi-leader models better describe the car-following models even if their higher complexity is accounted for, and that for the description of microscopic driving behaviour the reaction time is essential; models without a reaction time perform significantly worse.

Territory is a salient issue in post-communist countries in Europe, yet subnational elections have received surprisingly little attention. This article analyses congruence between national and regional elections in Croatia, the Czech Republic, Hungary, Poland, Romania and the Slovak Republic held between 1993 and 2010. The findings suggest that election incongruence can be partly explained by approaches which work well in the West European context – territorial cleavages, regional authority and the second-order election model – but in order to fully grasp regional election outcomes in post-communist countries one also needs to take into account electoral alliance strategies and party supply change.

A proposed lane change model can be integrated with a car-following model to form a complete microscopic driver model. The model resembles traffic better at a macroscopic level, especially regarding the amount of traffic volume per lane, the traffic speeds in different lanes, and the onset of congestion. In a new approach, lane change incentives are combined for determining a lane change desire. Included incentives are to follow a route, to gain speed, and to keep right. Classification of lane changes is based on behavior that depends on the level of lane change desire. Integration with a car-following model is achieved by influencing car-following behavior for relaxation and synchronization, that is, following vehicles in adjacent lanes. Other improvements of the model are trade-offs between lane change incentives and the use of anticipation speed for the speed gain incentive. Although all these effects are captured, the lane change model has only seven parameters. Loop detector data were used to validate and calibrate the model, and an accurate representation of lane distribution and the onset of congestion was shown.

The role of neutrophils as key players in the regulation of innate and adaptive immune responses is increasingly being recognized. We report that human neutrophils establish a network with both natural killer (NK) cells and 6-sulfo LacNAc+ dendritic cells (slanDCs), which ultimately serves to up-regulate NK-derived interferonγ (IFNγ). This network involves direct reciprocal interactions and positive amplification loops mediated by cell-derived cytokines. Accordingly, we show that after lipopolysaccharide + interleukin-2 (IL-2) or IL-15/IL-18 stimulation, neutrophils directly interact with and potentiate the activity of both slanDCs and NK cells. On the one hand, neutrophils augment the release of IL-12p70 by slanDCs via a CD18/ intercellular adhesion molecule-1 (ICAM-1) interaction that stimulates activated NK cells to produce IFNγ. IFNγ further potentiates the interaction between neutrophils and slanDCs and the release of slanDC-derived IL-12p70, thus creating a positive feedback loop. On the other hand, neutrophils directly costimulate NK cells via CD18/ICAM-3, leading to the production of IFNγ. Colocalization of neutrophils, NK cells, and slanDCs, as well as of IL-12p70 and IFNγ, in inflamed tissues of Crohn disease and psoriasis provides strong evidence for a novel cellular and cytokine cooperation within the innate immune system in which neutrophils act as amplifiers of NK cell/slanDC-mediated responses.

The role of neutrophils as key players in the regulation of innate and adaptive immune responses is increasingly being recognized. We report that human neutrophils establish a network with both natural killer (NK) cells and 6-sulfo LacNAc+dendritic cells (slanDCs), which ultimately serves to up-regulate NK-derived interferonγ (IFNγ). This network involves direct reciprocal interactions and positive amplification loops mediated by cell-derived cytokines. Accordingly, we show that after lipopolysaccharide + interleukin-2 (IL-2) or IL-15/IL-18 stimulation, neutrophils directly interact with and potentiate the activity of both slanDCs and NK cells. On the one hand, neutrophils augment the release of IL-12p70 by slanDCs via a CD18/ intercellular adhesion molecule-1 (ICAM-1) interaction that stimulates activated NK cells to produce IFNγ. IFNγ further potentiates the interaction between neutrophils and slanDCs and the release of slanDC-derived IL-12p70, thus creating a positive feedback loop. On the other hand, neutrophils directly costimulate NK cells via CD18/ICAM-3, leading to the production of IFNγ. Colocalization of neutrophils, NK cells, and slanDCs, as well as of IL-12p70 and IFNγ, in inflamed tissues of Crohn disease and psoriasis provides strong evidence for a novel cellular and cytokine cooperation within the innate immune system in which neutrophils act as amplifiers of NK cell/slanDC-mediated responses.

Samenvatting: Elektronische netwerken in de zorg winnen aan belang. Zorgaanbieders kunnen via uitwisseling van informatie via een elektronisch netwerk de zorgverlening aan hun patiënten kwalitatief beter, efficiënter en veiliger doen verlopen. Ook zorgaanbieders die niet vanaf de oprichting van een netwerk zijn aangesloten, moeten in een later stadium alsnog onder voorwaarden kunnen aansluiten. In de praktijk blijkt deze toetreding niet altijd soepel te verlopen. Zowel de Nederlandse Mededingingsautoriteit (NMa) als de Nederlandse Zorgautoriteit (NZa) heeft aangegeven hoe zorgaanbieders die deelnemen aan een elektronisch netwerk moeten omgaan met zorgaanbieders die wensen toe te treden: het moet transparant zijn hoe een zorgaanbieder tot het netwerk kan toetreden en de voorwaarden voor toetreding moeten redelijk, objectief en niet discriminerend zijn. De regeling die de NZa hier in december 2009 voor heeft vastgesteld, moet ervoor zorgen dat toetreding in de praktijk vergemakkelijkt wordt. Dit artikel schetst de bredere context van deze voorwaarden aan elektronische netwerken en bespreekt wat toetreders van deelnemers aan een netwerk mogen verwachten.

Generating the transient electrophilic tungsten pentacarbonylphenylphosphinidene complex PhPWCO5in the presence of 2,7dimethylocta2,3,5,6tetraene leads to the formation of a 3,4disubstituted phosphole or a complexed phospholene, depending on the reaction conditions. The formation of the phospholene results from the reaction of PhPWCO5with the diallene, while the formation of the phosphole arises from reaction with 3,4diisopropylidenecyclobutene, which is formed in situfrom the isomerization of the conjugated allene.

Scanning probe microscopy is at the verge of revolutionizing microscopy once again. Video‐rate scanning tunneling microscope (STM) and video‐rate atomic force microscope (AFM) technology will enable the direct observation of many dynamic processes that are impossible to observe today, such as atom or molecule diffusion, real time film growth, or catalytic reactions. In this paper we discuss the critical aspects that have to be taken into account when working on increasing the imaging speed of scanning probe microscopes. We highlight the state‐of‐the‐art developments in the control of the piezoelectric scanning elements and describe the latest innovations regarding the design and construction of the whole mechanical loop including new scanner geometries. We identify critical aspects for which no obvious solution exists and aspects where advanced control engineering can help, like piezo non‐linearities, the acceleration limit and the challenging technical requirements for the preamplifiers that are needed for measuring a tunneling current. Finally, we provide an overview of a number of new directions that are being pursued to solve the problems currently encountered in scanning probe technology. Copyright © 2009 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society

1,2‐Addition of transient W(CO)5‐complexed phosphinidenes exoto hexamethyl Dewar benzene affords the novel 3‐phosphatricyclo[3.2.0.02,4]hept‐6‐ene complexes. The fused tricyclic phosphiranes are obtained as both the Zand the thermally less stable Eisomers, the 31P NMR chemical shifts of which differ by about 60 ppm. A computational investigation shows that the phosphorus pyramidalization and the presence of the γ double bond are responsible for this effect. The semiquantitative results contribute to a more systematic understanding of the structural influences on 31P chemical shieldings. The congested double bond of the Zisomer can be epoxidized with m‐chloroperbenzoic acid (MCPBA) to afford a fused tetracyclic P,O bis‐adduct.

Phosphorus-based macrocycles with acetylenic scaffolds have been built from acetylene-substituted phosphane oxides that were formed from diisopropylphosphoramidic dibromide (3) and an acetylenic Grignard reagent. The four- and six-edged macrocycles 15 and 16, in which the iPr2NP(O) units are connected through 1,3-butadiyne rods, were obtained from the monosilylated derivative of iPr2NP(O)(C2H)2 (7) by multiple acetylene coupling reactions under oxidative Hay conditions. Reaction of iPr2NP(O)(Br)2 (3) with lithiated 1,2-diethynylbenzene gave a mixture of cis and trans monocyclic bis(phosphane oxide) 18. An X-ray crystal structure determination of the trans isomer shows the ring structure to adopt a puckered form.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)

Novel transient phosphinidene complex Ph−PMo(CO)4PMe3, generated from a 7-phosphanorbornadiene precursor, adds to CC and CC bonds to give Mo(CO)4PMe3-complexed phosphiranes and phosphirenes. The cis-PMe3ligand weakens the interaction between the molybdenum complex and the three-membered ring. Under mild CO pressure the Mo(CO)4PMe3transition metal group detaches from the phosphorus center of the ring structure by selective CO substitution. The resulting byproduct Mo(CO)5PMe3can be reused in the synthesis of the phosphinidene precursor.

Intramolecular phosphinidene addition to the CC bond of Mo‐complexed, seven‐membered phosphorus heterocycles affords three novel [(diphos)Mo(CO)4] complexes (18–20). The three bidentate phosphorus baskets differ in the composition of the seven‐membered ring: one of the phosphorus atoms is flanked by CH2, NCH3, or O. The unsaturated tetrahydrophosphepine precursors are synthesized by either ring‐closing metathesis (C and N derivatives) or by a cyclization sequence (O derivative). The crystal structures of the nitrogen‐ (19) and oxygen‐containing (20) baskets have relatively small P‐Mo‐P angles of 76.240(13)° and 77.626(12)°, respectively, and complex 20has slightly shortened MoP bond lengths.

Novel, highly stable, linear and branched mono‐ and diphospha[n]triangulanes were synthesized in high yields by the CuCl‐catalyzed phosphinidene addition to spirocyclopropanated methylenecyclopropanes and bicyclopropylidenes. The effect of spirofusion on the electronic properties of these esthetically attractive phosphacycles is apparent from X‐ray single crystal structure analyses, which reveals a tightening of the phosphirane ring on additional spirocyclopropanation, and from the NMR features that show deshielded chemical shifts for the ring‐phosphorus and ‐carbon atoms. Steric factors play a role in the addition reaction when the substrate alkene carries a second sphere of spirocyclopropane rings and causes the formation of 2‐phosphabicyclo[3.2.0]heptenes in small amounts. These by‐products most probably result from addition of the [PhP(Cl)W(CO)5]‐Cu‐L (L=alkene or solvent) reagent to the spirocyclopropanated bicyclopropylidene to give an intermediate σ‐complex, which subsequently, facilitated by steric factors, undergoes a cyclopropylcarbinyl to cyclobutyl ring expansion followed by a [1,3]‐sigmatropic shift.

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A phosphaspiropentene is the plausible kinetic product from the addition of dichlorocarbene to a phosphatriafulvene, which rearranges to a novel P-substituted triafulvene. The calculated barrier of 18.6 kcal mol^-1 for this process is consistent with the temperature of −40 °C at which this reaction proceeds.

Reaction of the transient phosphinidene complexes R‐PW(CO)5with N‐substituted‐diphenylketenimines leads unexpectedly to the novel 2‐aminophosphindoles, as confirmed by an X‐ray crystal structure determined for one of the derivatives. Experimental evidence for a methylene‐azaphosphirane intermediate was found by using the iron‐complexed phosphinidene iPr2N‐PFe(CO)4, which affords the 2‐aminophosphindole together with the novel methylene‐2,3‐dihydro‐1H‐benzo[1,3]azaphosphole. Analysis of the reaction pathways with DFT indicates that the initially formed methylene‐azaphosphirane yields both phosphorus heterocycles by way of a [1,5]‐ or [1,3]‐sigmatropic shift, respectively, followed by a H‐shift. Strain underlies both rearrangements, which causes these remarkably selective conversions that can be tuned by changing the substituents.

The synthesis of highly strained bicyclic phosphirane and phosphirene iron–tetracarbonyl complexes, that is, complexes with 2‐aza‐1‐phosphabicyclo[n.1.0]alkanes and ‐alkenes (n=3–5), is explored by using intramolecular cycloaddition of an in situ generated electrophilic phosphinidene complex, [R(iPr)NPFe(CO)4], to its CC‐ and CC‐containing R substituent. Saturated bicyclic complexes 7 a–cwith n=4–2 are remarkably stable, as illustrated by the X‐ray crystal structure for 7 b(n=3), yet all readily undergo retroaddition to react with phenylacetylene. Shuttling of the phosphinidene iron complex between two equivalent CC groups is demonstrated for a 1‐butene‐substituted 2‐aza‐1‐phosphabicyclo[3.1.0]hexane by selective 1H NMR magnetization transfer from the phosphirane protons to the olefinic protons. Even the more strained unsaturated bicycles 17 a,b(n=4,3) are surprisingly stable as illustrated by the X‐ray crystal structure for 17 a(n=4), but the smaller phosphabicyclo[3.1.0]hex‐5‐ene (17 c, n=2) dimerizes to tricyclic 19with a unique ten‐membered heterocyclic ring; an X‐ray crystal structure is reported. Like their saturated analogues also the bicyclic phosphirenes readily undergo retroaddition as shown by the reaction of their phosphinidene iron moiety with phenylacetylene.

Reaction of electrophilic phosphinidene complex [MePW(CO)5] with 1,6‐methano‐[10]annulene results in the sole formation of the isomeric CC insertion products 6 c(main) and 6 d(minor). The single‐crystal X‐ray structure of the complexed 1,7‐methano‐3‐phospha[11]annulene (6 c) shows a syn‐W(CO)5group at the exobent phosphorus. The structure displays CC bond alternation without bonding between the bridgehead carbon atoms. Density functional theory calculations indicate 6 cto result from a concerted disrotatory ring opening of an undetected tricyclic exo–synphosphirane intermediate. The endo–antiphosphirane cannot undergo ring expansion, due to the high barrier that is associated with an intramolecular antara–antararetro Diels–Alder reaction. The stabilizing effect of transition‐metal coordination is discussed.

The properties of the 16‐electron phosphinidene complex [CpRIrPR] were investigated experimentally and theoretically. Density functional theory calculations show a preferred bent geometry for the model complex [CpIrPH], in contrast to the linear structure of [CpIrNH]. Dimerization to give [{CpIrPH}2] and ligand addition to afford [Cp(L)IrPH] (L=PH3, CO) were calculated to give compounds that were energetically highly favorable, but which differed from the related imido complexes. Transient 16‐electron phosphinidene complex [Cp*IrPAr] could not be detected experimentally. Dehydrohalogenation of [Cp*IrCl2(PH2Ar)] in CH2Cl2at low temperatures resulted in the novel fused‐ring systems 17(Ar=Mes*) and 20(Ar=Mes), with dimeric [{Cp*IrPAr}2] being the likely intermediate. Intramolecular CH bond activation induced by steric factors is considered to be the driving force for the irreversible formation of 17and 20. ONIOM calculations suggest this arises because of the large steric congestion in [{Cp*IrPAr}2], which forces it toward a more reactive planar structure that is apt to rearrange.

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Reaction of an in situ generated phosphinidene complex [PhPW(CO)5] with the aromatic azulene and guaiazulene leads to unexpected 1,4‐adducts of the seven‐membered ring and to CH bond insertion of the five‐membered ring. A DFT analysis suggests that the reaction is initiated by formation of a η1‐complex between the phosphinidene and the five‐membered ring of the aromatic substrate. Four conformations of this complex were identified. Two convert without barrier to the slightly more stable syn‐and anti‐1,2‐adducts. These undergo pericyclic 1,7‐sigmatropic rearrangements with remarkably low barriers to give 1,4‐adducts, with an inverted configuration at the phosphorus center. An X‐ray crystal structure is presented for one of the 1,4‐adducts of guaiazulene. The other two η1‐complexes insert with modest barriers into a CH bond of the five‐membered ring.

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The novel phosphinidene complex [Cp*(NHC)Ir&dbond;PMes*] (3; NHC=1,3-diisopropyl-4,5-dimethylimidazol-2-ylidene) was prepared in high yield from [Cp*(NHC)IrCl2] (2) and [LiPHMes*]·3 THF. It represents the first example of an NHC ligated transition metal phosphinidene complex. The X-ray crystal structure for 3 is also reported. DFT calculations on the N-heterocyclic carbene containing parent complexes [Cp(NHC)Ir&dbond;E] (E=PH, NH, CH2) show that the NHC ligand acts as good σ-donor/weak π-acceptor ligand and forms strong Ir&bond;C(NHC) single bonds. The Ir&dbond;E double bonds result from strong triplet–triplet interactions between [Cp(NHC)Ir] and E.

Novel, very stable ruthenium and osmium containing terminal phosphinidene complexes [(η6‐Ar)(L)MPMes*] (Ar=benzene, p‐cymene; L=PR3, CO, and RNC) have been prepared by dehydrohalogenation of novel [(η6‐Ar)MX2(PH2Mes*)] complexes in the presence of a stabilizing ligand. Xray crystal structures are reported for [(η6‐C6H6)(PPh3)RuPMes*] (9) and [(η6‐pCy)(PPh3)OsPMes*] (4). Dehydrohalogenation in the absence of a stabilizing ligand resulted in the new Pspiroannulated Ru2P2‐ring structure 16. Dehydrohalogenation in the presence of but‐2‐yne gave a novel phosphaallyl complex [(η6‐Ar)Ru(η3‐R2PC(Me)CHMe)] 26, for which an Xray crystal structure is reported. The mechanism by which 16and 26are obtained is presumed to involve the intermediate formation of the 16‐electron (η6‐benzene)RuPMes* phosphinidene complex.

Novel terminal rhodium- and cobalt-complexed phosphinidenes, Cp*(PR3)Rh&dbd;PAr (3−5) and Cp(PPh3)Co&dbd;PAr (8), were obtained by dehydrohalogenation of the primary phosphine complexes Cp*RhCl2(PH2Ar) (2) and CpCoI2(PH2Ar) (7) in the presence of a phosphine. X-ray crystal structures are reported for Cp*(PPh3)Rh&dbd;PMes* (3) and Cp(PPh3)Co&dbd;PMes* (8). A comparative reactivity study and a computational survey were performed on the Co-, Rh-, and Ir-containing phosphinidene complexes. All react with organic dihalides to form phosphaalkenes, with the rhodium congener being far more reactive than the iridium and cobalt complexes. Density functional theory calculations give geometrical parameters and ³¹P NMR chemical shifts in good agreement with experimental data. The rhodium congeners exhibit the most pronounced charge separation of the Rh&dbd;P bond, which may explain its higher reactivity. The M−L bond is strong in all Cp(L)M&dbd;PH (M = Co, Rh, Ir) complexes and inhibits reactivity at the metal center. Comparisons with the Zr-containing complex Cp2(PH3)Zr−PH are made.

Superfluid phase transitions are discussed from a geometrical perspective as envisaged by Onsager. The approach focuses on vortex loops which close to the critical temperature form a fuctuating vortex tangle. As the transition is approached, vortex lines proliferate and thereby disorder the superfluid state, so that the system reverts to the normal state. It is shown in detail that loop proliferation can be described in exactly the same way as cluster percolation. Picturing vortex loops as worldlines of bosons, with one of the spatial coordinates interpreted as the time coordinate, a quantitative description of vortex loops can be given. Applying a rotation (to superfluids) or a magnetic field (to superconductors), which suppresses the formation of vortex loops and instead can lead to open vortex lines along the field direction, is shown to be equivalent to taking the nonrelativistic limit. The nonrelativistic theory is the one often used to study vortex lattice melting and to describe the resulting entangled vortex liquid.

Stable, crystalline iridium-complexed phosphinidenes, Cp*(L)Ir&dbd;PR, are readily synthesized by (a) the reaction of Cp*(L)IrCl2 (2, L = PPh3) with LiPHMes* and (b) dehydrohalogenation of Cp*(PH2R)IrCl2 (5, R = Mes*, Is, Mes) with in situ capturing of transient Cp*Ir&tbd1;PR (4) with phosphines, phosphites, arsines, isocyanides, and carbon monoxide (L). Cp*Ir&tbd1;PR eluded direct detection. The X-ray crystal structures are reported for Cp*(PPh3)Ir&dbd;PMes* (3) and Cp*(CO)Ir&dbd;PMes* (15). The more congested 3 has an E configuration for its Ir&dbd;P bond, whereas 15 is obtained in its Z form. The ³¹P NMR chemical shifts and ²JPP coupling constants are diagnostic for the E and Z forms. More shielded phosphinidene resonances and larger coupling constants are typical for the E isomers. These iridium-complexed phosphinidenes react with gem-diiodides to form phosphaalkenes, but not with carbonyl groups.

Soft PVC children's products are usually plasticized with phthalates. As young children suck and chew on toys, they extract and ingest certain quantities of the plasticizers. Some phthalates are suspected to affect the kidneys and liver and cause testicular damage. Therefore, the EC has prohibited the sale of toys and childcare articles intended to be placed in the mouth by children <3 years of age made of soft PVC containing >0.1% by weight of six phthalates (1999/815/EC). The aim was to study the materials and plasticizers used in soft children's products. In February 2001, a market surveillance was performed in The Netherlands and 62 soft toys were sampled. Forty-seven of these toys contained plasticized PVC. Diisononylphthalate (DINP) and di(2-ethylhexyl)phthalate (DEHP) were the predominant plasticizers and were usually found in concentrations between 30 and 45% by weight. One teething ring was made of PVC plasticized with 45% by weight of DINP and was not in compliance with Decision 1999/815/EC. The DINP and DEHP migration was determined in saliva simulant using the 'Head over Heels' agitation method. All toys complied with the Scientific Committee on Toxicity, Ecotoxicity and the Environment (SCTEE) guidance release value of 6.7 µg min-1 10 cm-2. The DEHP migration of six toys exceeded the SCTEE guidance release value of 1.7 µg min-1 10 cm-2. Substitutes found for phthalates plasticizers are acetyltributylcitrate, tributylcitrate and diisononyladipate. In addition, other plasticizers and additives were found in minor amounts. The toxicity and the migration behaviour of these substances is less known and requires more attention. To ensure the safety of PVC toys, these substances should also be regulated.

The electrophilic phosphinidene complex PhPW(CO)5 reacts with bis(imine) 5, possessing a single carbon spacer, to give the C−N insertion product 6. B3LYP/6-31G* calculations indicate that this process occurs by way of a 2,3-sigmatropic shift from the initially formed phosphane ylide. The alternative, 1,3-dipolar cycloaddition, followed by ring-opening of the bicyclic structure, can be ruled out since both steps are energetically much more demanding. Ring-closure to an azaphosphirane is also less favorable than the C−N insertion, which is in agreement with the absence of such a product in the experiment. (© Wiley-VCH Verlag GmbH, 69451 Weinheim, Germany, 2002)

Heating the nonchelating cis-bis-7-phosphanorbornadiene-[Mo(CO)4] complex (13) results in the thermal decomposition of one of the 7-phosphanorbornadiene groups. The phosphinidene thus generated adds intramolecularly to a C=C bond of the other ligand to give the novel diphosphorus complex 14. This reaction constitutes a metal-template-directed synthesis. Likewise, the intramolecular phosphinidene addition to the C=C bond of a Mo-phospholene ligand affords the diphos complex 18. Its crystal structure exhibits an extremely small P-Mo-P bite-angle for a five-membered chelate ring. The similar intramolecular 1,2-addition to a C=C bond of a phosphole ligand gives a highly strained, unstable intermediate product. Scission of its P−Mo bond generates a free coordination site, which is then occupied by either CO or a phosphole to yield complexes 22 and 23, respectively. The analogous intermolecular addition of [PhPW(CO)5] to a [phosphole-W(CO)5] complex gives the di-[W(CO)5] complexed adduct 28. The directing effect of the metal on the intra- and intermolecular additions is discussed.

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The terminal phosphinidene complex PhPW(CO)5 adds to the imine bond of PhHC=N−Ph to give 3-membered ring azaphosphiridines, which undergo ring-expansion with an additional imine to yield a set of four isomeric five-membered ring diazaphospholanes. Treatment with the diimines PhHC=N-(CH2)n-N=CHPh (n=2,3,4) results instead—in all three cases—in only a single isomer of the (CH2)n bridged diazaphospholane. For n=2 or 3, this aminal group is easily hydrolyzed to afford new 6- and 7-membered ring heterocycles. No intermediate azaphosphiridine complex is observed during the addition reaction to the diimines. B3LYP/6–31G* calculations on an unsubstituted, uncomplexed system suggest that the initially formed P,N-ylide of the H2C=N-(CH)2-N=CH2 diimine both kinetically and thermodynamically favors an intramolecular 1,3-dipolar cycloaddition over an imine insertion into the CPN ring of an intermediate azaphosphiridine. Single-crystal X-ray structures for the (CH2)2-bridged azaphospholane complex and the HCl adduct of the 7-membered hydrolysis product are presented.

The terminal phosphinidene complex PhPW(CO)5 reacts with 2,4,6-tri-tert-butyl-1,3,5-triphosphabenzene to give two unexpected multicyclic organophosphorus compounds. One of them results from an initial 1,2-addition, followed by an intramolecular rearrangement. B3LYP/6–31G* calculations on simplified parent systems suggest that the reaction follows a unique concerted reaction pathway. The second, and major, product is a tetraphosphaquadricyclane derivative, which presumably results from an intramolecular [2+2] cycloaddition of an intermediate tetraphosphanorbornadiene complex. Single-crystal X-ray structures are presented for both products.

Maintenance of a food and nutrient database for dietary research involves providing the right foods and nutrients for study participants, while keeping the database a size and format that can be updated rapidly and completely. The database must include (1) foods reported by study participants, (2) new foods that appear in the marketplace, (3) nutrients of research interest, and (4) for each food, a nutrient profile with no missing values. For efficient and timely updating, the database is kept to a manageable size by (1) grouping foods of similar nutrient content into a single database entry; (2) adding only foods widely consumed by most study participants; (3) including foods as usually prepared; (4) including foods only if adequate nutrient data are available; (5) allowing ingredients to be varied to provide multiple nutrient profiles from a single recipe, and (6) providing researchers the ability to add foods specific to their study to their individual database. The Nutrition Data System for Research (NDS-R) maintained by the Nutrition Coordinating Center at the University of Minnesota is a research tool used to collect and analyze dietary intake data. The food and nutrient database within NDS-R includes commodity and brand name foods commonly consumed in the United States, as well as foods for special ethnic and age group populations. Currently, this database contains 108 nutrients or food components for 17 000 foods.

Abstract:: A stack of tensionless membranes with nonlinear curvature energy and vertical harmonic interaction is studied. At low temperatures, the system forms a lamellar phase. At a critical temperature, the stack disorders vertically in a melting-like transition.

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Kinetics of Lewis base(LB) complexed primary and secondary σ‐alkyllithiums (RLi) with triphenylmethane (TPMH) are reported. Among the properties investigated are the effective reaction orders (see diagram), precomplexation and mechanism, and relative reactivities of tetrameric and dimeric RLis, both for primary and secondary R.