A formula for thermal stability (Tm) prediction of PNA/DNA duplexes

An empirical formula for thermal stability (T m) prediction of PNA/DNA duplexes has been derived. The model is based on the T m as calculated for the corresponding DNA/DNA duplex employing a nearest neighbour approach, by including terms for the pyrimidine content and length of the PNA to take into account the increased thermostability of PNA/DNA hybrids and the asymmetry of the PNA-DNA heteroduplex. The predictive power of the T m prediction formula was challenged with an independent data set not used for model building. The T m of >90% of the sequences was predicted within 5 K; 98% of the predicted T ms differ by not more than 10 K from the experimentally determined T m.     

Raised cerebrovascular resistance in idiopathic orthostatic intolerance: evidence for sympathetic vasoconstriction

We examined the gelatinolytic activity in human oral squamous-cell carcinoma tissues in order to evaluate the capability of intravasation and extravasation of cancer cells. By a microdissection-zymography, we demonstrated separately the gelatinolytic activities in cancer cell nests and stroma adjacent to the cancer cells. The gelatinolytic activities, such as pro-matrix metalloproteinase (MMP)9 and active-MMP2 in most of cancer cell nests were much higher than those of normal gingival epithelium. Moreover, the activities of active-MMP2 in cancer cell nests of metastatic cancers were significantly higher than those of non-metastatic cancers (p<0.05). These results suggest that active-MMP2 in cancer cells can be a predictive marker for metastasis formation in oral squamous-cell carcinoma patients.     

Gender, motivation, and coping in the evaluation of leadership effectiveness.

Examined the effects of gender, coping, and motivational orientation in evaluating individual leadership. Ss were 17 female and 31 male graduate students in an intensive leadership development program at a leading business school. The Shanan Sentence Completion Technique, Jackson's Personality Research Form, and Raven's Advanced Progressive Matrices were used to predict peer ratings of leadership at the end of the 9-mo program. The data reveal significant gender differences on the measures of motivation, with men showing higher levels of agentic instrumental tendencies and women exhibiting higher levels of communal-social qualities. These qualities, in turn were differentially correlated with evaluations of leadership. Women exhibiting strong agentic characteristics were negatively perceived as leaders. There was no relationship between agentic or communal qualities and evaluations of leadership received by male leaders. Finally, individuals with active coping tendencies were evaluated as more effective leaders for both genders. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Local linear perceptrons for classification

A structure composed of local linear perceptrons for approximating global class discriminants is investigated. Such local linear models may be combined in a cooperative or competitive way. In the cooperative model, a weighted sum of the outputs of the local perceptrons is computed where the weight is a function of the distance between the input and the position of the local perceptron. In the competitive model, the cost function dictates a mixture model where only one of the local perceptrons give output. Learning of the local models' positions and the linear mappings they implement are coupled and both supervised. We show that this is preferable to the uncoupled case where the positions are trained in an unsupervised manner before the separate, supervised training of mappings. We use goodness criteria based on the cross-entropy and give learning equations for both the cooperative and competitive cases. The coupled and uncoupled versions of cooperative and competitive approaches are compared among themselves and with multilayer perceptrons of sigmoidal hidden units and radial basis functions (RBFs) of Gaussian units on the application of recognition of handwritten digits. The criteria of comparison are the generalization accuracy, learning time, and the number of free parameters. We conclude that even on such a high-dimensional problem, such local models are promising. They generalize much better than RBF's and use much less memory. When compared with multilayer perceptrons, we note that local models learn much faster and generalize as well and sometimes better with comparable number of parameters.     

Analysis of cylindrical-to-plane-wave conversion by volume holograms

The properties of volume holograms produced by the interference of a cylindrical and a plane wave are studied. By analogy with Kogelnik's treatment of the plane wave, coupled differential equations are derived, and solved, for a transmission hologram illuminated by a cylindrical wave.     

Production of highly-sinterable rare-earth oxide powders by controlled humidity dewatering of precursors

The sintering behavior of rare-earth oxide powders produced from reverse strike hydroxide, oxalate and carbonate precursors was studied. The influences of controlled humidity dewatering of precursors on powder morphology and sintering behavior were extensively studied, and were compared with those produced by oven drying or dewatering by using organic washes (ATA method). Significant differences in behavior were observed for hydroxide- and carbonate-derived powders dewatered in different ways; oxalate-derived powders showed little behavioral dependence on dewatering method. In general, controlled humidity dewatering proved effective in leading to highly-sinterable powders from any of the three precursors investigated, ATA treatment was effective for hydroxide and oxalate precursors, and oven drying generally led to good sinterability only for oxalate-derived powders. Compaction behavior and surface area of the powders were also determined and attempts were made to correlate these characteristics with sintering behavior.     

Apparatus and instruments for the laboratory study of multi–anchored flexible retaining walls

Details are presented of the apparatus and instruments developed for the study of the behaviour of laboratory scale multi–anchored flexible retaining walls. The instruments enabled measurements to be made of the earth pressures on and the bending moments in very flexible walls. The shearing and thrust forces at wall base level and the individual anchor wire loads, as well as the movements of the wall and the retained sand, were also monitored throughout a simulated wall construction sequence.