Ascorbic acid turnover in the ocular tissues of some fishes

The ascorbic acid turnover from the ocular tissues of 11 species of fishes from a culture pond and the river Godavari (Andhra Pradesh, India) has been studied. The free ascorbic acid and ascorbigen contents were more in the case of bottom or deep dwelling fishes and the least in the case of surface living forms, depending upon the light penetration in the area that each species inhabits. The enzymic utilization and ascorbic acid-macromolecule complex varied among the fishes possibly depending upon individual energy requirements and not upon light intensity. No size-related or sex-related variation was observed. No variation was observed between riverine and pond-reared fishes of the same species.

Intra- and interspecific variation of the CCR5 gene in higher primates

We have evaluated the molecular evolution of the chemokine receptor CCR5 in primates. The chemokine receptor CCR5 serves as a major co-receptor for human immunodeficiency virus/simian immunodeficiency virus (HIV/SIV) infection. Knowledge of evolution of the CCR5 molecule and selection on the CCR5 gene may shed light on its functional role. The comparison of differences between intraspecific polymorphisms and interspecific fixed substitutions provides useful information regarding modes of selection during the course of evolution. There is marked polymorphism in the CCR5 gene sequence within different primate species, whereas sequence divergence between different species is small. By using contingency tests, we compared synonymous (SS) and nonsynonymous (NS) CCR5 mutations occurring within and between a broad range of primates. Our results demonstrate that CCR5 evolution did not follow expectations, of strict neutrality at the level of the whole gene. The proportion of NS to SS at the intraspecific level was significantly higher than that observed at the interspecific level. These results suggest that most CCR5 NS polymorphisms are slightly deleterious. However, at domains more closely correlated with its known biological functions, there was no obvious evidence to support deviation from neutrality.

Genetic variation survey of intra-specific (Sepia pharaonis) in the Persian Gulf and the Oman Sea using PCR-RFLP

This research was conducted to identify Cuttlefish population (Sepia pharaonis) in The Persian Gulf and the Oman Sea using PCR-RFLP. Specimens were collected from )0 different stations. Bottom trawling method was used for sampling from different zones of the Persian Gulf and the Oman Sea, and finally specimens from S. Pharaonis were collected at each station . DNA was extracted by phenol—Coloroform method. One pair primer was designed based on 1As rRNA gene nucleotide sequences. The results obtained from 1 As rRNA gene RFLP, which was reproduced by PCR technique, were analyzed and utilized for study of diversity of the Cuttlefish population. PCR product with o pair base in length achieved for all specimens, which was subjected to enzymatic digestion by A restriction action enzymes: Alu I-Taq I-Mnl I-Rsa I-Hind III-Dra I-vu II and Hae II DNA bands patterns in all specimens digested by those enzymen showed similarity with no any polymorphism. From this result, it can be concluded that there is not any possibility to isolate different populations in the studied Cuttlefish species under exploitation of rRNA gene.

Unsupervised intra-lingual and cross-lingual speaker adaptation for HMM-based speech synthesis using two-pass decision tree construction

Hidden Markov model (HMM)-based speech synthesis systems possess several advantages over concatenative synthesis systems. One such advantage is the relative ease with which HMM-based systems are adapted to speakers not present in the training dataset. Speaker adaptation methods used in the field of HMM-based automatic speech recognition (ASR) are adopted for this task. In the case of unsupervised speaker adaptation, previous work has used a supplementary set of acoustic models to estimate the transcription of the adaptation data. This paper first presents an approach to the unsupervised speaker adaptation task for HMM-based speech synthesis models which avoids the need for such supplementary acoustic models. This is achieved by defining a mapping between HMM-based synthesis models and ASR-style models, via a two-pass decision tree construction process. Second, it is shown that this mapping also enables unsupervised adaptation of HMM-based speech synthesis models without the need to perform linguistic analysis of the estimated transcription of the adaptation data. Third, this paper demonstrates how this technique lends itself to the task of unsupervised cross-lingual adaptation of HMM-based speech synthesis models, and explains the advantages of such an approach. Finally, listener evaluations reveal that the proposed unsupervised adaptation methods deliver performance approaching that of supervised adaptation.

A controller for a miniature intra-aortic ventricular assist device.

Two control algorithms have been developed for a minimally invasive axial-flow ventricular assist device (VAD) for placement in the descending aorta. The purpose of the device is to offload the left ventricle and to augment lower body perfusion in patients with moderate congestive heart failure. The VAD consists of an intra-aortic impeller with a built-in permanent magnet rotor and an extra-aortic stator. The control algorithms, which use pressure readings upstream and downstream of the VAD to determine the pump status, have been tested in a mock circulatory system under two conditions, namely with or without afterload sensitivity. The results give an insight into controller design for an intra-aortic blood pump working in series with the heart.

Design method of an innovative motor for an intra-aortic ventricular assist device

A permanent-magnet motor has been designed for an innovative axial-flow ventricular assist device (VAD), to be placed in the descending aorta, intended to offload the left ventricle and augment renal perfusion in patients with congestive heart failure (CHF). For this application, an intra-aortic impeller with a built-in permanent magnet rotor is driven by an extraaortic stator working in synchronism with the natural heart. To meet this need, a two-dimensional analytical model has been developed in the MATLAB environment to estimate machine parameters; finite element analysis (FEA) has been used to refine the results. A prototype blood pump equipped with an innovative motor designed from the procedure above has been tested in a mock loop representing the human circulatory system. The performance of VAD incorporating the motor is presented. © 2009 IEEE.