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The dynamics of the guanine-cytosine base pair has been studied in the time-dependent quantum approach. A six-dimensional model involving the nonlinear three hydrogen bridges has been utilized. The modifications induced in the hydrogen transfer from a base to the other by the explicit inclusion of the out-of-plane hydrogen atom position in the three bridges have been evidenced and the consequences on stacking interaction and base pair opening are considered. The relevance of these aspects in biological properties has been suggested. [ABSTRACT FROM AUTHOR]

Transition state dynamics of dissociation and association reactions N2O4⇋2NO2 in liquid state are studied by classical molecular dynamics simulations of reactive liquid NO2 at 298 K. An OSPP+LJ potential between NO2 molecules proposed in paper I [J. Chem. Phys. 115, 10852 (2001)], which takes into account the orientational sensitivity of the chemical bond, has been used in the simulation. The trajectory and energy evolution of various reactions are studied in the OSPP+LJ liquid, which reproduces both the observed liquid phase equilibrium constant and Raman band shape of the dissociation mode. It is found that a NO2 pair in reactive liquid NO2 is bound when ET<0 and dissociates when ET>0, and the dissociation of a reactant pair occurs when the transition state (TS) surface of ET=0 is crossed from negative to positive, where ET is the sum of the potential and kinetic energies of intermolecular motion of the pair. Two types of dissociation are found depending on the source of energy for dissociation; the first type D is the dissociation via collisional activation of the reactive mode by solvent molecules, and the second type T is the dissociation via bond transfer from a dimer to a monomer NO2 through the TS of NO2 trimer. It is concluded that the type T dissociation is found to be much more probable than the type D dissociation because of easy energy conservation. The reactant experiences the TS of NO2 trimer for a long time (1–10 ps) in NO2 mediated bond transfer reactions, and crossing and recrossing trajectories and dynamics in the TS neighborhood are studied. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

A wealth transfer from bondholders to stockholders is one of several hypotheses used to explain stockholder gains on the announcement of a spin-off. However, previous empirical research has not found systematic evidence supporting the wealth expropriation hypothesis. Using a larger sample with comprehensive bond data, we find evidence consistent with wealth expropriation. Bondholders, on average, suffer a significant negative abnormal return during the month of the spin-off announcement. However, even accounting for the loss to the bondholders, the aggregate value of the publicly traded debt and equity increases on a spin-off announcement, suggesting that the wealth expropriation hypothesis is not a complete explanation of the stockholder gains. In explaining the magnitude of the losses to bondholders, we find they are a function of the loss in collateral in the spun-off subsidiary and the level of financial risk of the parent firm. Consistent with a loss to bondholders, firms are more likely to have their credit rating downgraded than upgraded after a spin-off. Additionally, consistent with the wealth transfer hypothesis, losses to bondholders tend to be more severe, the larger the gains to shareholders. [ABSTRACT FROM AUTHOR]

Recent models of herding suggest that speculators may rationally trade on information unrelated to fundamentals when their trading horizons are short. This study provides an empirical example where this appears to be the case. Johnson Redbook's weekly retail sales figures predicted bond returns for a short time after a significant number of bond traders began purchasing and trading on the data. The significant relationship between the data and bond returns disappeared just after the Wall Street Journal started to report it. Meanwhile, there was little or no change in the relationship between the data and retailers' stock returns, perhaps because the data have long been followed by retail stock analysts, Johnson Redbook's original investor clientele. [ABSTRACT FROM AUTHOR]

Time evolution of prestress loss and bond transfer length holds vital information concerning long-term performance of pretensioned prestressed concrete. In this paper, it is proposed to utilize long-term measurements of strand draw-in to extract this time-varying information, which could be more effectively obtained than concrete or strand surface strain measurements. Theoretical investigations combined with numerical studies of experimental data are carried out for this purpose. This study builds on Guyon’s boundary value problem (BVP) model which quantifies draw-in for instantaneous elastic response. A one-dimensional linear viscoelastic standard solid model is employed to model the creep of concrete, which is a simple but effective model of the time-dependent response of concrete. Guyon’s BVP model is generalized to include time dependence and then combined with an existing initial value problem (IVP) model for post-tensioned concrete leading to a new mixed model for time-dependent prestress loss and bond transfer in pretensioned concrete. Analysis is undertaken in this study to (i) quantify long-term prestress loss and bond-transfer behaviors by applying the proposed model and directly utilizing measured draw-in time history data, (ii) validate the proposed quantitative analysis by using scaled pretensioned concrete beams with different types of aggregates and strengths of concrete - among other factors, and (iii) offer discussion of future work. For example, introducing concrete drying shrinkage into the proposed simple model seems promising and is necessary to provide an improved representation of the time-dependent behavior of prestressed concrete. [ABSTRACT FROM AUTHOR]

Transfer hydrogenative coupling of styrene with primary alcohols using the precatalyst HClRu(CO)(PCy3)2 modified by AgOTf or HBF4 delivers branched or linear adducts from benzylic or aliphatic alcohols, respectively. Related 2-propanol mediated reductive couplings also are described. [ABSTRACT FROM AUTHOR]

The 133Cs magic-angle spinning NMR spectra of the paramagnetic compounds CsMII[MIII(CN)6], MII = Ni, Co, Fe, Mn; MII = Co, Fe, yield unusually large and temperature-dependent signal shifts (up to −950 ppm relative to CsCl at 298 K). Comparison with the spectra of the diamagnetic analogues CsM[Co(CN)6], M = Zn, Cd, shows that the shifts are largely due to the unpaired electrons. This is ascribed to through-bond transfer of spin to the Cs+ ions, while the through-space effect of the magnetic moments on the signal shifts is shown to be virtually negligible. The mechanism inducing negative spin at Cs+ is discussed. The magnitude of the spin density (average: |5.8 × 10-3| (a.u.) -3) suggests that Cs+ is involved in magnetic exchange interactions of corresponding Prussian blue derivatives. [ABSTRACT FROM AUTHOR]

Skeletal rearrangement of O-propargylic formaldoximes, in the presence of gold catalysts, afforded 4-methylene-2-isoxazolines in good to excellent yields by an intermolecular methylene transfer. In addition, the cascade reaction with maleimide in the presence of a gold catalyst afforded isoxazole derivatives by cyclization/methylene transfer and a subsequent ene reaction, whereas that using a copper catalyst gave oxazepines through a 2,3-rearrangement. [ABSTRACT FROM AUTHOR]

Aktivierung aromatischer Aldehyde: Die oxidative Aktivierung von 2 ‐ Methylindol ‐ 3 ‐ carboxaldehyd (I) durch ein N ‐ heterocyclisches Carben (NHC) führt zur Bildung eines heterocyclischen ortho ‐ Chinodimethan ‐ Derivats (II) als Schlüsselintermediat. Dieses reagiert in einer formalen [4+2] ‐ Cycloaddition mit Trifluormethylketonen oder Isatin, wodurch Lactone mit einem quartären Stereozentrum aufgebaut werden. [ABSTRACT FROM AUTHOR]

Highlights: [•] Using DFT to study the intermolecular methyl-to-double bond transfer. [•] One possible pathway is the methyl attack on the terminal carbon of the double bond. [•] The other is the formation of the bridged methylonium ion. [•] The transfer pathway is mainly associated with the type of alkene rather than that of methyl donor. [•] For S-substituted methylsulfonium ion, electron-withdrawing group can promote methyl transfer. [ABSTRACT FROM AUTHOR]

Slabs are one of the main load-bearing elements in nearly every structure. Because of additional live loads or modifications of the building structure these slabs often have to be strengthened. Using externally bonded carbon-fiber reinforced polymer (CFRP) strips to strengthen existing concrete structures has become common practice. One of the main failure modes is the loss of the composite action between the concrete and the CFRP strip making the bond force transfer very important. This bond force transfer depends on many parameters including the concrete strength, the ratio between shear force, and bending moment. A new parameter recently discovered by the Technische Universität München (TUM) is the deflection of the structural elements themselves. Because of this deflection self-inducted contact pressure occurs. This contact pressure affects a higher bond transfer. The lower effective depth of slabs compared to beams causes higher deflections. In this article, first a few principles on the strengthening with adhesive-bonded CFRP strips and the characteristics of the bond are explained. Then, the basics of the bond force transfer, at the end anchorage and in the rest of the element, are summarized. Based on these essentials, as well as numerous experiments, the change in the bond force transfer at the structural element caused by the curvature is then derived. With these findings, a complete verification concept is presented, which is ideal for computerized calculations. This verification concept is finally compared to several full-scale test results presented in pertinent literature. [ABSTRACT FROM AUTHOR]

This note extends the solution concept of the core for traditional transferable-utility (TU) games to multi-choice TU games, which we name the unit-level-core. It turns out that the unit-level-core of a multi-choice TU game is a “replicated subset” of the core of a corresponding “replicated” TU game. We propose an extension of the theorem of Bondareva (Probl Kybern 10:119–139, 1963) and Shapley (Nav Res Logist Q 14:453–460, 1967) to multi-choice games. Also, we introduce the reduced games for multi-choice TU games and provide an axiomatization of the unit-level-core on multi-choice TU games by means of consistency and its converse. [ABSTRACT FROM AUTHOR]

Abstract: Regression results show that more unequal societies tend to spend comparatively more on higher levels of education. In a two-period model with heterogeneous agents, this paper investigates the political determinants of this bias. In the first period, public education is financed by the incumbent government by issuing bonds. Investments in basic and higher education have conflicting effects on future labour income distribution and net returns to these investments depend on the tax and transfers system being selected in the following period through the democratic process. Our idea is that public investment in basic education, by decreasing future labour income inequality, may induce future policy-makers to redistribute resources through financial rents taxation, thus making unfeasible the issuing of debt to finance basic education. This will be the more probable the greater wealth inequality is. [Copyright &y& Elsevier]

Concrete-filled steel tube (CFT) components provide an attractive alternative to conventional methods of construction. The steel tube serves as formwork and reinforcement to the concrete fill. The fill delays local buckling of the tube and increases the compressive strength, stiffness and ductility of the CFT member if composite action is achieved. As such, the benefits of using CFT components include their efficiency, economy and ability to provide rapid construction. The primary obstacles to using CFT components relate to achieving adequate shear-stress transfer between the two materials needed for composite behavior and to developing robust, constructible connections. There is considerable interaction between this stress transfer and the connections joining CFT members to other structural elements. In many cases, natural bond stress, primarily friction, is adequate to ensure good structural performance of the CFT member, but in other cases mechanical interlock or bearing between the steel and concrete is required. While some mechanical transfer elements may supplement the natural bond transfer, others may destroy this beneficial effect. Additionally, natural bond may be dramatically enhanced by bending of the CFT member and by using appropriate connections to join other members to the CFT element. Therefore, proper quantification and understanding of natural, enhanced and mechanical sources of bond stress are needed to develop robust CFT structural components and their connections. [ABSTRACT FROM AUTHOR]

The article discusses the purpose of the transfer bond statute, the problems that arise when it is applied to actual cases, and the potential solutions to the failures of the current statutory model in Florida. It states that the objective of the statute is to allow a property owner facing a claim of lien to transfer that lien off the property to other security. It suggests that changes to the statute should involve simplification of the administration of transfer bonds by courts and litigants.

Abstract: External bonding of FRP plates or sheets has emerged as a popular method for strengthening reinforced concrete structures. Debonding along the FPR–concrete interface can lead to premature failure of the structures. In this study, a combined cohesive/bridging zone model is presented to simulate the debonding procedure between the FRP and concrete interface. In this model, the crack processing zone of the interface is modeled by a cohesive zone model and the particle interlocking zone of the interface is modeled by a bridging zone model. Two different linearly softening bond stress–slip laws are used to describe these two different zones. Closed-form solutions of interfacial stress, FRP stress and ultimate load are obtained for a typical single-lap specimen and verified with experimental results. The pulling force applied to the FRP plate is found to be proportional to the square root of the energy release rate at the debonding tip for this model. Such a relationship is then extended to any general shapes of bond stress–slip law through J-integral method. A new approach to experimentally determine the bond stress–slip law is also proposed. [Copyright &y& Elsevier]

In this paper we propose a discrete-time model with fixed maximum time to maturity of traded bonds. At each trading time, a bond matures and a new bond is introduced in the market, such that the number of traded bonds is constant. The entry price of the newly issued bond depends on the prices of the bonds already traded and a stochastic term independent of the existing bond prices. Hence, we obtain a bond market model for the reinvestment risk, which is present in practice, when hedging long term contracts. In order to determine optimal hedging strategies we consider the criteria of super-replication and risk-minimization. [ABSTRACT FROM AUTHOR]

The article provides information on the Article 8 of the Uniform Commercial Code (UCC) governing investment securities in the U.S. In 2006, the New York Court of Appeals decided to classify promissory notes as Article 8 securities after the sale of the Schneider family's apparel companies to McNaughton Apparel Group. Under the Section 8-401, the issuer must register transfer of a certified security if certain conditions are meet. Court cases regarding attachment are also discussed.

An experimental program on 12 series of specimens with different embedment lengths to determine the transfer length was conducted. Transfer length test results of seven-wire strand on twelve different concrete mixtures were analyzed. A testing technique based on the analysis of bond behavior by means of measuring the force supported by the tendon has been used. The specimens had been instrumented with slip measurement devices at each end of the specimen. A sequence of slip values at each end of the specimen after release versus the embedment length has been analyzed. The expressions relating the transfer length to the tendon end slip are presented. A value of Guyon's factor for tendon stress distribution shape has been obtained. Two criteria to determine the transfer length from the slip sequences at both ends of the specimens have been analyzed. [ABSTRACT FROM AUTHOR]

A fragment of the structure of a sulfo cation exchanger, which is the basis of most cation-exchange membranes, is calculated by an ab initio method. An analysis of interatomic bonds in the structure shows that, to detach a mobile ion from a fixed ion, it is necessary to break the hydrogen bond between hydration water molecules of the counterion in addition to overcoming the electrostatic attraction. As the hydrogen bond cleavage work for simple hydrated ions is ten times the electrostatic attraction energy, an elementary act of ion transport in a cation-exchange membrane is considered mostly as the hydrogen bond transfer reaction. [ABSTRACT FROM AUTHOR]

Objectives. Evaluation of a new surface treatment method to obtain a good bond strength between a luting composite and several ceramics.Methods. Specimen preparation and test procedure were done according to ISO 10477 Amendment 1. The surfaces of Empress II, InCeram-Alumina, InCeram-Zirconia and Frialit (ZrO2) were ground under water-cooling with 400 grit grinding paper, afterwards polished with 800 grit and air-dried. Each ceramic material investigated was divided into three groups of 10 specimens each. Group 1 was flame-treated with the PyrosilPen for 2.5 s, group 2 for 5 s and group 3 for 10 s/cm2. After the flame treatment, a methacryl silane was applied followed by a luting composite. Prior to measuring shear bond strength, the specimens were thermocycled 5000 times in a water-bath between +5 and +55 °C. Furthermore, SEM- and Fourier-transform infrared spectrophotometer (FT-IR)-investigations were done. As a control, Empress II etched and silaned was used.Results. Shear bond strength measurements indicated that the optimal treatment time was 5 s/cm2. Regarding this time the following bond strength values between the luting composite and the various ceramics were obtained: Empress II 23 (5) MPa, InCeram-Alumina 23 (5) MPa, InCeram-Zirconia 13 (8) MPa, and Frialit 16 (6) MPa. The control achieved 27 (6) MPa. On all surfaces of the flamed specimens Si could be detected by FT-IR.Significance. The PyrosilPen-Technology is an easy and effective method for surface-treating silicate, aluminum oxide and zirconium oxide ceramics to obtain good bonding to luting composites. [Copyright &y& Elsevier]

Calculations at the B3LYP/6-311+G(d,p)//B3LYP/6-311+G(d,p) level involving the atoms-in-molecules (AIM) and electron localization function (ELF) methods have been carried out for a variety of PO-bond-containing molecules in an effort to further characterize the phosphoryl bond. One cannot distinguish the phosphoryl bond from a conventional PO double bond by comparing bond distances. Both the bond breaking energies and delocalization indices do divide into the three classes of single, double, and phosphoryl and tend to parallel each other. On the basis of the PO bond in HPO having a reference bond order of 2.0, the phosphoryl bond has a bond order of about 1.3. Examination of localized orbitals confirm our ideas that the phosphoryl bond is highly polar as, indeed, are the other PO bonds. What sets the phosphoryl bond apart is the high degree of back-bonding that contributes to the delocalization index (and covalent bond order) and provides for its stronger-than-single-bond character and short bond distance. [ABSTRACT FROM AUTHOR]

The intramolecular hydrogen bonds of 2-nitroresorcinol, I, 4,6-dinitroresorcinol, II, and 2-nitrophenol, III, have been studied, in gas phase and in water solution, at ab initio level using the DFT-B3LYP approach and the 6-31G** basis set. The strength of the hydrogen bridges has been evaluated according to the classic procedure and by comparing the barriers to internal rotation of the studied compounds and those of nitrobenzene, phenol and resorcinol. The anions deriving from mono- and double-deprotonation were also taken into account to evidence the role of the hydrogen bridge in damping the relevant O⋯O intramolecular repulsive interactions The investigation in water solution was carried out by means of the PCM-SCRF method. The obtained results do not reveal particularly important variations in the geometrical parameters with respect to those of the gas phase, but non-negligible changes occurs in the net charge densities, bond electron population and hydrogen bond energies. ΔGsolv and deprotonation energies are also reported. [Copyright &y& Elsevier]

The article discusses the fundamental principles of securitization and the challenges inherent in perfection of asset transfers. It offers an argument that contingent transfers do not yield the kind of credit enhancement in a transaction that is consistent with structured finance methodology. It mentions the possible link of the argument that favors contingent transfer arrangements in the belief that a transferor will only become insolvent.

The check-processing activity represents a major function in a commercial bank. If checks are quickly processed through the bank, then funds will be transferred to appropriate accounts and the bank will experience minimum float. This paper discusses the use of priority rules to maximize the dollar value of checks processed each day. A series of experiments are developed to test a set of priority rules (heuristics) under different operating conditions of check processing capacity, transit dollar levels, and branch characteristics. The results indicate that significant differences in performance are present for different rules. Also, the usefulness of some rules are dependent upon the commercial bank's operating characteristics, which has important implications for operating managers. [ABSTRACT FROM AUTHOR]

This study examines securityholder returns around nine major repurchase announcements and 10 other repurchase-related announcements by the Teledyne Corporation between 1972 and 1984. Statistically significant positive excess returns to common stock and convertible preferred stockholders are documented. Contrary to prior research that investigated the aver- age response to repurchase announcements, however, there is a wealth transfer from bond- holders to stockholders. Bondholder returns around the repurchase announcements are significantly negative. These returns are examined for each announcement and each bond issue. [ABSTRACT FROM AUTHOR]

Focuses on the problem on policy transfers in contemplation of death in life insurance premiums in the United States. Types of policy transfers; Classes of interest included in the gross estate; Valuation of the interests transferred.