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In this paper, we present new interval oscillation criteria related to integral averaging technique for second order partial differential equations with delays that are different from most known ones in the sense that they are based on the information only on a sequence of subintervals of [t0,∞), rather than on whole half-line. Our results are sharper than some previous results and handles the cases which are not covered by known criteria.

In this paper, we propose a new feature extraction method-parameterized direct linear discriminant analysis (PD-LDA) for small sample size problems. Similar to direct LDA (D-LDA), PD-LDA is a modification of KLB (the Karhunen-Loeve expansion based on the between-class scatter matrix). As an improvement of D-LDA and KLB, PD-LDA inherits two important advantages of them. That is, it can be directly applied to high-dimensional input spaces and implemented with great efficiency. Meanwhile, experimental results conducted on two benchmark face image databases, i.e., AR and FERET, demonstrate that PD-LDA is much more effective and robust than D-LDA. In addition, it outperforms state-of-the-art facial feature extraction methods such as KLB, eigenfaces, and Fisherfaces.

Feature selection has been extensively applied in statistical pattern recognition as a mechanism for cleaning up the set of features that are used to represent data and as a way of improving the performance of classifiers. Four schemes commonly used for feature selection are Exponential Searches, Stochastic Searches, Sequential Searches, and Best Individual Features. The most popular scheme used in text categorization is Best Individual Features as the extremely high dimensionality of text feature spaces render the other three feature selection schemes time prohibitive. This paper proposes five new metrics for selecting Best Individual Features for use in text categorization. Their effectiveness have been empirically tested on two well- known data collections, Reuters-21578 and 20 Newsgroups. Experimental results show that the performance of two of the five new metrics, Bayesian Rule and F-one Value, is not significantly below that of a good traditional text categorization selection metric, Document Frequency. The performance of another two of these five new metrics, Low Loss Dimensionality Reduction and Relative Frequency Difference, is equal to or better than that of conventional good feature selection metrics such as Mutual Information and Chi-square Statistic.

Using a generalized Riccati transformation, some new oscillation criteria for second order partial differential equations with delays are found through the method of integral average. These results can be considered as generalizations and improvements of the results due to Kamenev in ordinary differential equations cases.

This paper investigates the global regulation problem for a class of nonlinear systems with integral input-to-state stable (iISS) dynamic uncertainty. By designing a reduced-order observer, a systematic output feedback control strategy is proposed. The designed dynamic controller can achieve the global set-point regulation control and guarantee all signals of the closed-loop systems bounded. The developed control schemes find its application in the pendulum control system. Simulation results verify its effectiveness.

The paper aims to discover the development rule of fetal parital bone. One hundred and eighty parietal bones of 5-38th weeks old were observed and measured. With the Noback's method every fetus was made transparent and then dyed dark red by the Alizarin red. The measured data are added to differential and integral calculus formula to calculate parietal ossification length and make correlated regression analysis. The results show that the time of ossification of different parts of fetal parietal bones are between the 9th and the 38th week. The parietal sagittal ossification length is 85.12 1.07mm an d the coronary ossification length is 82.62 1.24 mm. from the 37th to the 38th week, parietal coronary ossification bending appears. from the 13rd to the 14th week with the bending height being 3.74 0. 47, and sagittal ossification bending occurs from the 17th to the18th week with the bending height being 1.60  0. 45. Correlation analysis shows that parietal sagittal ossification length and coronary ossification length have highly positive correlation with gestational age respectively(r=0.9926, 0.9869,P ﹤0.01). Two regression equations are established, and parietal ossification diameter length can be estimated. It can be concluded that fetal parietal sagittal ossification length is greater than coronary ossification length. Coronary ossification bending appears earlier than sagittal ossification bending but sagittal bending height is greater than coronary bending height.

As an effective technique for feature extraction and pattern classification Fisher linear discriminant (FLD) has been successfully applied in many fields. However, for a task with very high-dimensional data such as face images, conventional FLD technique encounters a fundamental difficulty caused by singular within-class scatter matrix. To avoid the trouble, many improvements on the feature extraction aspect of FLD have been proposed. In contrast, studies on the pattern classification aspect of FLD are quiet few. In this paper, we will focus our attention on the possible improvement on the pattern classification aspect of FLD by presenting a novel linear discriminant criterion called maximum scatter difference (MSD). Theoretical analysis demonstrates that MSD criterion is a generalization of Fisher discriminant criterion, and is the asymptotic form of discriminant criterion: large margin linear projection. The performance of MSD classifier is tested in face recognition. Experiments performed on the ORL, Yale, FERET and AR databases show that MSD classifier can compete with top-performance linear classifiers such as linear support vector machines, and is better than or equivalent to combinations of well known facial feature extraction methods, such as eigenfaces, Fisherfaces, orthogonal complementary space, nullspace, direct linear discriminant analysis, and the nearest neighbor classifier.

In terms of environmental mineralogy, the environmental properties of metallic minerals, including chemical activation, adsorption, pore effect and nanometer effect, have been analyzed. On the basis of the analysis of environmental properties of metallic minerals, the applications of iron-bearing sulfides, iron and manganese oxides in the purification of wastewaters containing heavy metal ions (Cr6+, Hg2+, Pb2+, etc.) have been summarized. Moreover, research on the application of metallic minerals in environmental protection has been anticipated. It should be a piece of dominating work for environmental mineralogic researchers in the future to lucubrate systematically the physical and chemical characteristics of the metallic mineral surfaces, further reveal the reciprocity process between metallic minerals and water surface, perfect the theory and model of the metallic minerals to remove contaminants, intensify study on the facilities and techniques of metallic minerals to remove contaminants, and entail well the extension and propagation of achievements.

Teratomas are congenital tumors that derive from all 3 germ layers. Most teratomas of the head and neck present in the pediatricage group. We report a case of a 5-month-old infant who presented with a teratoma showing possible obstruction of the airway. The tumor was successfully resected under general anesthesia. The postoperative course was uneventful, and she was fine at a 3-year follow-up.

Some oscillation criteria are given for the second order matrix differential system Y + Q ( t ) Y = 0 Y+Q(t) Y=0 , where Y Y and Q Q are n × n n\times n real continuous matrix functions with Q ( t ) Q(t) symmetric, t ∈ [ t 0 , ∞ ) t\in [t_0,\infty ) . These results improve oscillation criteria recently discovered by Erbe, Kong and Ruan by using a generalized Riccati transformation V ( t ) = a ( t ) { Y ′ ( t ) Y − 1 ( t ) + f ( t ) I } V(t)=a(t)\{Y’(t) Y^{-1}(t) +f(t)I\} , where I I is the n × n n\times n identity matrix, f ∈ C 1 f\in C^1 is a given function on [ t 0 , ∞ ) [t_0,\infty ) and a ( t ) = exp ⁡ { − 2 ∫ t f ( s ) d s } a(t)=\exp \{-2 \int ^t f(s)\,ds\} .

The mediorostral neostriatum/hyperstriatum ventrale (MNH) and neostriatum dorsocaudale (Ndc) of the domestic chick are crucially involved in auditory filial imprinting, whereas the lobus parolfactorius (LPO) seems to be involved in the emotional modulation of behavior. Because there is evidence that MNH and Ndc are akin to higher association areas in mammals, the present study evaluates the dopaminergic and thalamic input to these areas, as well as to the avian caudate/putamen homologue LPO, by using retrograde pathway tracing, together with dopamine (DA) and tyrosine hydroxylase (TH) immunohistochemistry. By combining DA immunohistochemistry with retrograde fluorescent tracing, we demonstrated that dopaminergic afferents to the MNH and Ndc arise mainly from the area ventralis, whereas the main dopaminergic input to the LPO arises from the substantia nigra. The main thalamic input to the MNH and LPO arises from the dorsal thalamic nuclei, n. dorsomedialis anterior and n. dorsolateralis anterior, whereas the thalamic input to the Ndc arises from the n. dorsolateralis posterior and n. subrotundus. Furthermore, there are reciprocal intratelencephalic connections between distinct parts of the neostriatum caudale and the mediorostral neostriatum. DA-immunoreactive (ir) fibers are present at moderate densities in the MNH and Ndc and at high densities in the LPO. At the ultrastructural level, DA- and TH-ir axon terminals in the MNH and Ndc form predominantly symmetric synaptic contacts with dendritic shafts, which are often situated in close vicinity to unstained terminals. These results indicate that the general organization of dopaminergic afferents to the chick telecephalon is similar to that of the mesotelencephalic dopaminergic subsystems in mammals such as the mesostriatal and mesolimbocortical DA system. © 1996 Wiley-Liss, Inc.

It has been suggested that in skeletal muscle the force-velocity relationship may not be a simple hyperbolic one, as defined by Hill's equation. To determine whether smooth muscle demonstrated the same properties, quick-release force-velocity curves were obtained from canine tracheal smooth muscle. The results showed that the observed data points for tracheal smooth muscle systematically deviated from a hyperbola. Such deviation occurred at values of force (P) approaching maximum isometric force (Po) for curves elicited by quick release at 2 and 10 s in the course of isometric contractions. Shortening velocities under a given afterload were overestimated at the high-force end (P > 75% Po) by Hill's equation; this implied that a relationship more complex than a simple hyperbola was involved at high loads. We next focused on finding an equation to also fit those directly measured data points that did not conform to a hyperbola. Our rationale in developing the equation was that a plot of the linearized transform of Hill's equation should yield a straight line over the entire range of loads at which velocities were measured. The plot demonstrated that, in the low-load high-velocity portion of the curve, a peak value was reached at 70–80% Po, which decreased as load increased in the high-load low-velocity portion.(ABSTRACT TRUNCATED AT 250 WORDS)

Optimization of culture conditions for exopolysaccharide (EPS) by Funalia trogii in submerged culture was investigated using one-factor-at-a-time method and uniform design (UD). Under the optimized conditions, the maximum concentration of EPS was 8.68 g/l. After EPS was deproteinized by Sevag method, two groups of EPSs (designated as Fr-I and Fr-II) were obtained from the culture filtrates by gel filtration chromatography on Sepharose CL-6B. Furthermore, EPSs were characterized by size exclusion chromatography (SEC) coupled with a multiangle laser-light scattering (MALLS) and refractive index (RI) detector system. The weight-average molar masses of the Fr-I and Fr-II were determined to be 1.007 × 10(5) and 2.393 × 10(4)g/mol, respectively. The root mean square (RMS) radii for both peaks ranged from 9.7 to 10.8 nm with no clear trends. Pharmacology experiments indicated F. trogii EPS were useful to the therapy of free radical injury and cancer diseases.

The sliding mode, which is caused by the switching law, is studied for the planar closed-loop switched systems. Some new conceptions are developed based on the Euclid geometry. Both the existence conditions and stablity conditions of the sliding mode region around the given switching boundries are obtained by these conceptions. And the state feedback switching laws are designed to make sure the existence and stability of the sliding mode region. As an application of the theorems, a numerical simulation is shown to validate the main results.

Juveniles of many species, including humans, display greater airway responsiveness than do adults. This may involve changes in airway smooth muscle function. In the present work we studied force production and shortening velocity in trachealis from 1-wk-old (1 wk), 3-wk-old (3 wk), and 3-mo-old (adult) guinea pigs. Strips were electrically stimulated (60 Hz, 18 V) at their optimal length ( l o) to obtain maximum active stress (Po) and rate of stress generation. Then, force-velocity curves were elicited at 2.5 s from the onset of the stimulus. By applying a recently developed modification of Hill's equation for airway smooth muscle, the maximum shortening velocity at zero load ( V o) and the value α ⋅ γ/β, an index of internal resistance to shortening (Rsi), were calculated (α, β, and γ are the constants of the equation). Poincreased little with maturation, whereas the rate of stress generation increased significantly (0.40 ± 0.03, 0.45 ± 0.03, 0.51 ± 0.03 P o/s for 1 wk, 3 wk, and adult animals). V o slightly increased early with maturation to decrease significantly later (1.79 ± 0.67, 2.45 ± 0.92, and 0.55 ± 0.09 l o/s for 1 wk, 3 wk, and adult animals), whereas the Rsi showed an opposite trend (14.98 ± 5.19, 8.99 ± 3.01, and 32.07 ± 5.54 mN ⋅ mm−2 ⋅ l o −1 ⋅ s for 1 wk, 3 wk, and adult animals). This early increase of force generation in combination with late increase of Rsi may explain the changes of V o with age. An elevated V o may contribute to the incidence of airway hyperresponsiveness in healthy juveniles.

For the analysis of learning processes and the underlying changes of the shape of excitatory synapses (spines), 3-D volume samples of selected dendritic segments are scanned by a confocal laser scanning microscope. For a more detailed analysis, such as the classification of spine types, binary images of higher resolution are required. Simple threshold methods have disadvantages for small structures because the microscope point spread function (PSF) causes a darkening and a spread. The direction-dependent PSF leads to shape errors. To reconstruct structures and edge positions with a resolution smaller than one voxel a parametric model for the dendrite and the spines is created. In our application we use the known tree-like structure of the nerve cell as a- priori information. To create the model, simple geometrical elements (cylinders with hemispheres at the ends) are connected. The model can be adapted for size and position in sub-pixel domain. To estimate the quadratic error between the microscope image and the model, the model is sampled with the same resolution as the microscope image and convolved by the microscope PSF. During an iterative process the parameters of the model are optimized. In contrast to other pixel-based methods. the number of variable parameters is much slower. The influence of small deviations in the microscope image (caused by the inhomogeneous biological materials) is reduced.

For the analysis of learning processes and the underlying changes of the shape of excitatory synapses (spines), 3-D volume samples of selected dendritic segments are scanned by a confocal laser scanning microscope. The images are unsharp because of the (direction dependent) resolution limit. A simple deconvolution is not sufficient for the needed resolution.

The generalized composite rectangle (constant) rule for the computation of Cauchy principal value integral with the singular kernel cot[(x−s)/2] is discussed. Our study is based on the investigation of the point-wise superconvergence phenomenon, i.e., when the singular point coincides with some a priori known point, the convergence rate of the midpoint rule is higher than what is globally possible. We show that the superconvergence rate of the composite midpoint rule occurs at certain local coordinate of each subinterval and obtain the corresponding superconvergence error estimate. Some numerical examples are provided to validate the theoretical analysis.