Purification and properties of brain alkaline phosphatase

Alkaline phosphatase from sheep brain has been purified to homogeneity. The method includes butanol extraction, fractional ethanol precipitation, ion-exchange chromatography on DEAE-cellulose, and on DEAE-Sephadex followed by Sephadex G-200 filtration. By these steps, the enzyme is purified 22,920-fold with 15% recovery. The homogeneous enzyme is shown to be a sialoglycoprotein in nature. Neuraminidase treatment reduces the electrophoretic mobility of the enzyme. The enzyme shows pyridoxal phosphate phosphatase activity along with p-nitrophenylphosphate phosphatase activity. Both these compounds behave as mutual alternate competitive substrates. The general properties of the enzyme are described

Fluorescence studies on the interaction of some ligands with carcinoscorpin, the sialic acid specific lectin, from the horseshoe crab, Carcinoscorpius rotundacauda

The binding affinities of some ligands towards the sialic acid-specific lectin carcinoscorpin, from hemolymph of the horseshoe crab Carcinoscorpius rotundacauda have been determined by protein fluorescence quenching in presence of ligands. Among the ligands studied, the disaccharide O-(N-acetylneuraminyl)-(2→6)-2-acetamido-2-deoxy-D-galactitol has the highest Ka (l.15 × 106 M−1) for carcinoscorpin. Studies on the effect of pH on Ka values of disaccharide suggests the possible involvement of amino acid residues having pKa values around 6.0 and 9.0 in the binding activity of carcinoscorpin. There were distinct changes in the accessibility of the fluorescent tryptophan residues of carcinoscorpin by ligand-binding as checked through potassium iodide quenching

Two Qubits in the Dirac Representation

A general two qubit system expressed in terms of the complete set of unit and fifteen traceless, Hermitian Dirac matrices, is shown to exhibit novel features of this system. The well-known physical interpretations associated with the relativistic Dirac equation involving the symmetry operations of time-reversal T, charge conjugation C, parity P, and their products are reinterpreted here by examining their action on the basic Bell states. The transformation properties of the Bell basis states under these symmetry operations also reveal that C is the only operator that does not mix the Bell states whereas all others do. In a similar fashion, expressing the various logic gates introduced in the subject of quantum computers in terms of the Dirac matrices shows for example, that the NOT gate is related to the product of time-reversal and parity operators.Comment: 11 page

Is surgery the only option for unstable ankle fracture?

Background: Ankle fracture is one of the most common injuries in sports and daily activity. Unstable ankle fracture that are displaced fracture of the lateral malleolus and most bimalleolar or trimalleolar fractures need surgical reduction and fixation.Methods: It is a single centre study in which all unstable ankle fracture above the age of 18 and not associated with any other injury were included in the study. Following fixation patients were followed up at 6 weeks, 3 months and 6 months and functional outcome was assessed with American Orthopaedic Foot and Ankle score (AOFAS).Results: Supination external rotation injury was most common type. Mean AOFAS score at the end of six months was found to be best in supination adduction type. Posterior malleolus fixation with screw were found to have maximum AOFAS score.Conclusions: Surgical outcome in unstable ankle fracture are proved to have good functional outcome

Entangling capacity of global phases and implications for Deutsch-Jozsa algorithm

We investigate the creation of entanglement by the application of phases whose value depends on the state of a collection of qubits. First we give the necessary and sufficient conditions for a given set of phases to result in the creation of entanglement in a state comprising of an arbitrary number of qubits. Then we analyze the creation of entanglement between any two qubits in three qubit pure and mixed states. We use our result to prove that entanglement is necessary for Deutsch-Jozsa algorithm to have an exponential advantage over its classical counterpart.Comment: All 8 figures at the en

Analysis of Density Matrix reconstruction in NMR Quantum Computing

Reconstruction of density matrices is important in NMR quantum computing. An analysis is made for a 2-qubit system by using the error matrix method. It is found that the state tomography method determines well the parameters that are necessary for reconstructing the density matrix in NMR quantum computations. Analysis is also made for a simplified state tomography procedure that uses fewer read-outs. The result of this analysis with the error matrix method demonstrates that a satisfactory accuracy in density matrix reconstruction can be achieved even in a measurement with the number of read-outs being largely reduced.Comment: 7 pages, title slightly changed and references adde