Serbian Autobiographical Studies \u2013 A Survey

A survey of Serbian autobiographical studie

Expanding a fluorescent RNA alphabet: synthesis, photophysics and utility of isothiazole-derived purine nucleoside surrogates.

A series of emissive ribonucleoside purine mimics, all comprised of an isothiazolo[4,3-d]pyrimidine core, was prepared using a divergent pathway involving a key Thorpe-Ziegler cyclization. In addition to an adenosine and a guanosine mimic, analogues of the noncanonical xanthosine, isoguanosine, and 2-aminoadenosine were also synthesized and found to be emissive. Isothiazolo 2-aminoadenosine, an adenosine surrogate, was found to be particularly emissive and effectively deaminated by adenosine deaminase. Competitive studies with adenosine deaminase with each analogue in combination with native adenosine showed preference for the native substrate while still deaminating the isothiazolo analogues

Analysis of stray current induced by cathodic protection on steel-framed masonry structures

Cathodic protection (CP) has been successfully employed to protect steel-framed masonry buildings from corrosion related damage. When a CP system is installed to protect the structural members, other metallic items which are within the fabric of the structure but are not in direct electrical continuity may suffer from stray current interactions, resulting in accelerated corrosion of the discontinuous items. Therefore, these must be considered when CP systems are designed prior to installation. This paper presents both experimental and numerical studies into the risk and extent of stray current corrosion in steel-framed masonry structures when subject to impressed current cathodic protection. The objective is to allow CP systems to be optimised so that interference is minimised without compromising the technical or cost benefits of this method of corrosion control

Influence of shear reinforcement corrosion on the performance of under-reinforced concrete beams

The in-service performance of reinforced concrete beams can be severely affected through cor-rosion of the steel reinforcement when it becomes subjected to harsh corrosive environments containing chlo-rides and carbon dioxide. In such instances, corrosion is likely to occur in the steel reinforcement, with the expansive nature of the corrosion products likely to induce cracking and spalling of the concrete. A loss of structural integrity (stiffness) will occur and this can severely influence the serviceability of the member. The purpose of this paper is to investigate the relationship between degree of corrosion and loss of stiffness in corrosion damaged under-reinforced concrete beams. Beams (100mm x 150mm cross section) were subjected to accelerated corrosion in the laboratory and subsequently tested in flexure to failure. The paper reports on the results of these tests and relates the degree of corrosion in the main steel to the percentage loss in stiffness in the concrete beams

The Fractional Ornstein-Uhlenbeck Process: Term Structure Theory and Application

The paper revisits dynamic term structure models (DTSMs) and proposes a new way in dealing with the limitation of the classical affine models. In particular, this paper expands the flexibility of the DTSMs by applying a fractional Brownian motion as the governing force of the state variable instead of the standard Brownian motion. This is a new direction in pricing non defaultable bonds with offspring in the arbitrage free pricing of weather derivatives based on fractional Brownian motions. By applying fractional Ito calculus and a fractional version of the Girsanov transform, a no arbitrage price of the bond is recovered by solving a fractional version of the fundamental bond pricing equation. Besides this theoretical contribution, the paper proposes an estimation methodology based on the Kalman filter approach, which is applied to the US term structure of interest rates.Fractional bond pricing equation; fractional Brownian motion; fractional Ornstein-Uhlenbeck process; long memory; Kalman filter

Debt and Taxes: Evidence from bank-financed unlisted firms

This paper analyzes the capital structure decision of non-listed bank-financed firms using a rich and unique new data set of Portuguese firms. These firms are rarely studied in capital structure contexts and differ from large listed firms in terms of agency and asymmetric information problems and funding sources. It is argued that the solution of agency and asymmetric information problems for large firms shows up on the balance sheet (as restrictions on debt) whereas for small firms these problems are solved by financial institutions and are therefore less apparent on the balance sheet. This makes it easier for small firms to exploit tax advantages of debt. The empirical analysis shows that debt tax shields and provisions for tax loss carry-forwards have an important impact on the capital structure of small firms. It is also found that the balance sheet variables used for large listed firms in different countries to model agency costs and asymmetric information do not work well for small non-listed firms. The only significant variables (besides tax variables) for small firms are bankruptcy (collateral) variablesCapital Structure; Debt; Marginal Tax Rate; Trade-off Theory;

Investment Timing, Liquidity, and Agency Costs of Debt

This paper examines the effect of debt and liquidity on corporate investment in a continuous- time framework. We show that stockholder-bondholder agency conflicts cause investment thresholds to be U-shaped in leverage and decreasing in liquidity. In the absence of tax effects, we derive the optimal level of liquid funds that eliminates agency costs by implementing the first-best investment policy for a given capital structure. In a second step we generalize the framework by introducing a tax advantage of debt, and we show that an interior solution for liquidity and capital structure optimally trades off tax benefits and agency costs of debtinvestment timing; liquidity; agency costs of debt; capital structure; real options

A Consistent Pricing Model for Index Options and Volatility Derivatives

We propose and study a flexible modeling framework for the joint dynamics of an index and a set of forward variance swap rates written on this index, allowing options on forward variance swaps and options on the underlying index to be priced consistently. Our model reproduces various empirically observed properties of variance swap dynamics and allows for jumps in volatility and returns. An affine specification using L´evy processes as building blocks leads to analytically tractable pricing formulas for options on variance swaps as well as efficient numerical methods for pricing of European options on the underlying asset. The model has the convenient feature of decoupling the vanilla skews from spot/volatility correlations and allowing for different conditional correlations in large and small spot/volatility moves. We show that our model can simultaneously fit prices of European options on S&P 500 across strikes and maturities as well as options on the VIX volatility index. The calibration of the model is done in two steps, first by matching VIX option prices and then by matching prices of options on the underlyingNo keywords;

Dispersed Trading and the Prevention of Market Failure: The Case of the Copenhagen Stock Exchange

With augmented demands on power grids resulting in longer and larger blackouts combined with heightened concerns of terrorist attacks, trading institutions and policy makers have widened their search for systems that avoid market failure during these disturbing events. We provide insight into this issue by examining trading behavior at the Copenhagen Stock Exchange during a major blackout. We find that although market quality declined, markets remained functional and some price discovery occurred during the blackout period suggesting that the NOREX structure of interlinked trading systems combined with widely dispersed trading locations may be a viable means of protection against market failure during massive power disruptions or terrorist attacks.Power failure; Fragmented markets; Market failure;