Lipids fromPlasmodium vinckei-infected erythrocytes and their susceptibility to oxidative damage

The constituent lipids of plasma and red blood cells (RBC) from mice late in infection with the malarial parasitePlasmodium vinckei were analyzed and compared with those obtained from uninfected animals. On a dry weight basis, the total extractable lipids of RBC increased three-fold during infection, while those of the plasma did not change significantly. In general, changes in individual plasma lipid constituents paralleled those found in RBC of infected mice but were of smaller magnitude. While the increase in the total lipids of parasitized RBC was largely attributable to an increase of more than fourfold in total phospholipids, a significant increase in neutral lipids was also observed. Phosphatidylcholine and phosphatidylethanolamine were the major phospholipids present within RBC, and their total and relative concentrations increased as a result of the infection. A parallel increase occurred in the ratio of unsaturated to saturated fatty acids in the parasitized RBC phospholipids. Infection was also associated with decreases in the relative amount of cholesterol present in RBC and in the ratio of cholesterol to phospholipid. Consistent with this, the fluorescence polarization of 1[4-(trimethylamino)phenyl]-6-phenylhexa-1,3,5-triene within parasitized RBC plasma membranes was decreased in comparison with its value in noninfected RBC, indicating that malarial infection decreases the “order” of membrane lipids. These modifications, in conjunction with the increased levels of vitamin E and malonyldialdehyde reported elsewhere, are important determinants of the susceptibility of the different membrane compartments within infected RBC to peroxidative damage.     

Modeling of the mechanical alloying process

Two programs have been developed to compute the dimensional and property changes that occur with repetitive impacts during the mechanical alloying process. The more sophisticated of the programs also maintains a running count of the fractions of particles present and from this calculates a population distribution. The programs predict powder particle size and shape changes in accord with the accepted stages of powder development during mechanical alloying of ductile species. They also predict hardness and lamellar thickness changes with processing, again with reasonable agreement with experimental results. The benefits of these predictions are twofold. First, they offer support of the model (and thereby give insight into the possible “actual” happenings of mechanical alloying) and hence allow refinement and calibration of the myriad aspects of the model. Second, they provide a vehicle for establishing control over the dimensions and properties of the output powders used for consolidation, thereby facilitating optimization of the consolidation process.     

Naissance de l'ordre scolaire aux XVIIe et XVIIIe siècles et évolution des représentations psychosociales de l'enfance.

Describes the development of educational concepts and methods during the 17th and 18th centuries, with an emphasis on the origin of the differentiation between "normal" and "abnormal" school children. Psychosocial conceptualizations of childhood and educational concepts and methods that have led to the gradual integration of abnormal children into the regular school system are emphasized. (English abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Silk maysin content and resistance of commercial corn [maize] hybrids to kernel contamination by aflatoxin

Several phenols and related compounds have been shown to have detrimental effects on insects while others have antibiotic activity against fungi which attack higher plants. Insects have also been implicated as contributors to preharvest contamination of corn [maize], Zea mays L, by aflatoxin. The objectives, therefore, were to determine (a) if commercial corn hybrids vary in their silk maysin content and aflatoxin contamination of the grain, and (b) if grain aflatoxin contamination is correlated with maysin and related compounds. During 4 years of testing, 16 corn hybrids varied significantly for silk maysin content and grain aflatoxin contamination. Based on correlations, grain aflatoxin content of the hybrids tested was not significantly associated with maysin, chlorogenic acid, and 3′-methoxymaysin contents. It was concluded that other untested phenolic compounds in the category of compounds analyzed in the present study could be involved in resistance to aflatoxin formation, and that other classes of compounds should also now be assessed to locate major chemical resistance components.     

Constancy of psychotic syndromes in men and women.

Interview behavior ratings were obtained on the Inpatient Multidimensional Psychiatric Scale for 375 male and 448 female psychotics from 16 state and university hospitals. An hypothesis-testing factor analysis confirmed 11 of the 12 factors (syndromes) hypothesized. The congruency coefficients indicated essential constancy between men and women across the 11 syndromes established. 4 similar 2nd order factors accounted for the correlations among the factor scores in both groups. Comparisons of the 2 sexes as to score level revealed that the males were more retarded, while the females were more excited. Thus, men and women are quite similar as to the kinds of psychotic behaviors they exhibit. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Equalization issues in multicarrier transmission using filter banks

In multicarrier data transmission using filter banks, adaptive equalizers can be introduced in the receiver in every subchannel, to achieve high bit rates. Following conventional data transmission techniques, two approaches can be envisaged, namely the double sampling equalizer and the critical sampling equalizer. Both schemes are discussed and assessed in the present paper, in the multicarrier context. Estimations are given for the lengths of the equalizers as a function of the channel distortion and of the roll-off factor of the prototype filter in the receiver filter bank. The importance of the roll-off factor is stressed, since it controls the computational complexity of the system. Simulation results associated with two channel models are given to support the theoretical analysis. They show that the critical sampling approach has an advantage in computation rate over the double sampling scheme, when the prototype filter roll-off is above 0.5 and when the mean square output error is the performance criterion and no timing offset is introduced.     

Etude tachistoscopique de la spécialisation hémisphérique chez l'agénésique du corps calleux.

A brother (aged 9 yrs) and his sister (aged 18 yrs) with total agenesis (nondevelopment) of the corpus callosum and matched IQs (77–78 points) were administered a hemispheric-specialization task, using tachistoscopic presentation of visual stimuli, to investigate hemispheric specialization in callosal agenesis. A group of normal controls also completed the task for comparison. No differences were found between siblings and controls in terms of response accuracy. However, the 2 siblings showed abnormally long RTs and engaged more frequently in ocular scanning than controls. When a motor response was required, the siblings displayed a left visual-field superiority, regardless of the stimulus nature. Results are discussed in terms of abnormal organization of hemispheric function in callosal agenesis. (23 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)