In our experiment, LAD territory was larger than the AHA-proposed 17-segment model. The most specific segments were located at the anterior wall and supplied exclusively by LAD. No specific segment could be exclusively attributed to RCA or to LCx. Sometimes, LCx can be the most important artery for the blood supply of the inferior wall even if the origin of the posterior descending artery is the RCA.
In this work, the quantum confinement effect is proposed as the cause of the displacement of the vibrational spectrum of molecular groups that involve hydrogen bonds. In this approach the hydrogen bond imposes a space barrier to hydrogen and constrains its oscillatory motion. We studied the vibrational transitions through the Morse potential, for the NH and OH molecular groups inside macromolecules in situation of confinement (when hydrogen bonding is formed) and non-confinement (when there is no hydrogen bonding). The energies were obtained through the variational method with the trial wave functions obtained from Supersymmetric Quantum Mechanics (SQM) formalism. The results indicate that it is possible to distinguish the emission peaks related to the existence of the hydrogen bonds. These analytical results were satisfactorily compared with experimental results obtained from infrared spectroscopy.
This work addresses the task of feature extraction for classification when both labels and features are binary. Our approach aims to build features with reduced interaction effects, thus relieving the classifiers from dealing explicitly with interactions. We introduce a new technique for building binary features by means of a parity calculating matrix that changes the coordinates of a binary vector. That matrix can be built purposefully for manipulating specific information theoretic measures. The resulting transform gives rise to groups of binary variables. A new algorithm for independent component analysis of binary features is proposed, based on this technique. In the context of classification, a new algorithm is presented that reduces the conditional dependence of features, given the label. A third algorithm presented in this text reduces the Interaction Information between pairs of features, a measure associated with redundancy or collaboration among predictors. This algorithm is used in the context of designing two-level operators for binary images. This type of operator combines the responses of several first-level operators to create the output image. In this case, the interaction reducing algorithm handles the division of the image into subregions. A complete framework for designing these operators is provided, involving feature selection and model comparison techniques. Experimental results show that the proposed method generates more accurate operators, compared to the single-level ones.
Recently, we have presented a study that describes the use of an analytical technique to provide the shift on the frequency of the OH and NH groups present in a series of biological macromolecules. The shift in the vibrational frequency occurs because of the formation of hydrogen bonds between the group and a donor atom of the macromolecule, inducing quantum confinement. [1] To describe such proposition, we have used the variational method associated with Supersymmetric Quantum Mechanics which is essentially an algebraic method of quantum mechanics, to provide the energy spectra of the system before the hydrogen bond formation (system unconfined) and after the hydrogen bond formation (confined system). The main virtue of our method is its simplicity.The Schr€ odinger equation was written with the Morse potential, notably a phenomenological potential with exact analytical solution, introduced in 1929 by Morse to treat molecular problems. [2] The unconfined problem is, therefore, exact whereas the confined problem (with the hydrogen bond) has to have an approximation method to solve the Schr€ odinger equation in a region surrounded by infinite walls, characterizing the confinement space where the hydrogen vibrates. The infinite walls are settled at the edges of the two atoms around the hydrogen, meaning that the hydrogen cannot penetrate inside them. The main point is the use of the cut-off terms (y max 2 y) (y 2 y min ), which multiply the unconfined (exact) wave function to describe the confined wave function, where (y max 2 y min ) is the region of space where the hydrogen vibrates. These two parameters, y min and y max , are related to the covalent radius of the atom for which the hydrogen is chemically bound and the van der Waals radius complementary of hydrogen bond, respectively. The other parameters involved are the equilibrium distance, the energy dissociation, and the reduced mass, which are characteristic of the Morse potential.The variational functions imply an approximation of what would be the actual functions for the studied problem and thus imply the assumption that the function would be close to the real one. The variational parameters used to minimize the energy eigenvalues must also reflect the correction of any distortions that alienate such a solution from the real solution of the problem. There is no evidence that this does not occur in this study. Rather, the convergence between experimental and theoretical values indicates that the suggested wave functions are appropriate for describing the desired system.It should be remarked that the Morse potential is not a first principles potential but a potential constructed from the phenomenology. Seeking a conceptual reach the same potential is used for different environmental conditions where the hydrogen bonds appear. The quantitative results presented in the literature confirm this practice. There are no arguments or strong evidence at the moment to abandon this attitude in the incorporation of confinement to the description of hydrogen bonds in d...
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