Multi-Level Clustering and its Visualization for Exploratory Spatial Analysis

Exploratory spatial analysis is increasingly necessary as larger spatial data is managed in electro-magnetic media. We propose an exploratory method that reveals a robust clustering hierarchy from 2-D point data. Our approach uses the Delaunay diagram to incorporate spatial proximity. It does not require prior knowledge about the data set, nor does it require preconditions. Multi-level clusters are successfully discovered by this new method in only O(nlogn) time, where n is the size of the data set. The efficiency of our method allows us to construct and display a new type of tree graph that facilitates understanding of the complex hierarchy of clusters. We show that clustering methods adopting a raster-like or vector-like representation of proximity are not appropriate for spatial clustering. We conduct an experimental evaluation with synthetic data sets as well as real data sets to illustrate the robustness of our method.     

Fast Cluster Polygonization and its Applications in Data-Rich Environments

We develop a linear time method for transforming clusters of 2D-point data into area data while identifying the shape robustly. This method translates a data layer into a space filling layer where shaped clusters are identified as the resulting regions. The method is based on robustly identifying cluster boundaries in point data using the Delaunay Diagram. The method can then be applied to modelling point data, to displaying choropleth maps of point data without a reference map, to identifying association rules in the spatial dimension for geographical data mining, or to measuring a gap between clusters for cluster validity.

Home observations of family interactions of depressed women.

The family interactions of 27 intact families with clinically depressed mothers were compared with those of 25 normal families. Each family had at least one child between the ages of 3–16 years. Spouses in half of the depressed families were maritally distressed. A system of coding interactions was developed, and observations were conducted in each home on 10 separate days. Six categories of nonverbal affective behavior were analyzed. Depressed mothers emitted significantly higher rates of dysphoric affect and lower rates of happy affect than normal mothers. Among depressed families, the mother"s dysphoric affect appeared to suppress the family"s aggressive affect, whereas the family"s aggressive affect appeared to suppress the mother"s dysphoric affect. These data suggest that aversive behavior may function to provide brief respites from the aversive behavior of others. The presence of marital discord in depressed families appeared to exacerbate such problematic interaction. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Austenite stabilization in Cr 13% Ni 4–6% steels

The present article deals with the study of the effects of concentration changes taking place in the matrix during partial austenitization of Cr 13% Ni 4–6% steel, while it is tempered, in the range of intercritical temperatures, on the structural stability of forming austenite. In the investigation, the authors made use of some special techniques of the potential polarization method and electron microanalysis. Some geometrical factors, such as the morphology and distribution of austenite areas were also studied. Increased austenite content in the matrix provides for an increased level of plastic properties and for improved technological characteristics. The stability of austenite areas depends on their morphology, distribution and, above all, on their dimensions - their thickness should not exceed 0.15 to 0.20 μm. The increase in nickel content observed in these areas was as much as 100% compared with the nominal nickel content of this steel.     

A new look at motivated inference: Are self-serving theories of success a product of motivational forces?

People construct idiosyncratic, self-serving models of excellence or success in social domains, in part, to bolster self-esteem. In 3 studies, participants tended to articulate self-serving theories of success under experimental conditions in which pressures to maintain self-esteem were present, but not under conditions in which such pressures were absent. Participants assigned to role-play being a therapist were more self-serving in their assessments of the characteristics needed to be a "successful therapist" than were participants assigned to observe the role play (Study 1). Participants failing at an intellectual task articulated self-serving theories about the attributes crucial to success in marriage (Study 2) and evaluated targets similar to themselves more favorably than they did dissimilar targets (Study 3), tendencies not observed for participants succeeding at the task. Discussion centers on issues for future research suggested by these findings. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Interdialytic weight gain and nutritional parameters in chronic hemodialysis patients

The extent of interdialytic weight gain (IDWG) in chronic hemodialysis patients is usually attributed to the level of compliance with fluid restriction. However, in view of the substantial water content of food (and caloric content of beverages), IDWG also may be a function of calorie and protein intake and may reflect the nutritional state of patients. To investigate this theory, the relationship between 2-day IDWG and body weight, normalized protein catabolic rate (nPCR), serum albumin, and delivered Kt/V urea was assessed in a prospective, randomized study of 860 chronic hemodialysis patients in 56 dialysis units. Compared with patients having < 2 kg IDWG (n = 378), patients with > 3 kg IDWG (n = 138) weighed more (dry weight, 76.8 v 61.7 kg), had higher nPCR (1.15 v 0.96 g/kg/d), and had higher serum albumin levels (3.96 vs 3.79 g/dL) (all P < 0.001) but did not have different levels of Kt/V (1.04 v 1.06). When IDWG was assessed as a function of dry weight, patients with IDWG > 4.5% of dry weight (n = 151) had higher nPCR (1.17 v 0.94 g/kg/d) but weighed less (60.1 v 70.0 kg) and had a higher Kt/V (1.14 v 1.01) than patients with IDWG < 3% of dry weight (n = 355) (all P < 0.001). Artifactual association between IDWG and nPCR attributable to an accentuated two-pool effect from differing ultrafiltration requirements was unlikely as assessed by the relationship between modeled Kt/V and prescribed Kt/V determined using an anthropometric urea volume.(ABSTRACT TRUNCATED AT 250 WORDS)     

Identification of a graft versus host disease-associated human minor histocompatibility antigen

Minor histocompatibility antigen disparities between human leukocyte antigen (HLA)-matched bone marrow donors and recipients are a major risk factor for graft versus host disease (GVHD). An HLA-A2.1-restricted cytotoxic T cell clone that recognized the minor histocompatibility antigen HA-2 was previously isolated from a patient with severe GVHD after HLA-identical bone marrow transplantation. The HLA-A2.1-bound peptide representing HA-2 has now been identified. This peptide appears to originate from a member of the non-filament-forming class I myosin family. Because HA-2 has a phenotype frequency of 95 percent in the HLA-A2.1-positive population, it is a candidate for immunotherapeutic intervention in bone marrow transplantation.     

Steering rules for AGV based on primitive function and elementary movement control

The complete structure of an AGV control system is described in the first part of this paper. The AGV control system is hierarchical and consists of five levels. The structure of one level does not depend on the structures of the other levels. This means that the control system depends on the design of the AGV at the lowest level only, at the actuator servo-control level and its coordination in realizing AGV primitive functions.The second part of the paper describes rules applicable to AGV steering. The structure of these rules depends on two groups of factors. The first group is dependent on information groups fed to the AGV processor by the position sensor. The second group of factors represents aims and conditions and AGV steering such as positioning accuracy, positioning time, allowed room for maneuver, the shape of the given trajectory, etc. The AGV steering rules contain sequences of primitive functions. These primitive functions are of such types as “turn left”, “straighten” (correct), “go straight on”, etc. Trajectory, as one of the basic factors, is defined at the level of controlling an elementary movement. The term “to control an elementary movement” means to select a transport road throughout the transport network and to code it using “elementary movement” such as “go straight” (relating to road section), “turn left” (relating to turning at a crossroad) etc.The results of the AGV steering simulation are presented in the third part of the paper. An exact kinematic AGV model used for stimulating control models is also presented.     

Solution of combinatorial optimization problems with minimax criterion

We consider the combinatorial optimization problem with a single criterion and with an ordered system of criteria (OSC) including minimax criteria (MMC) and minimum sum criteria (MSC). An algorithm is developed reducing MMC to MSC while preserving the set of optima. This leads to a technique for scalarizing the OSC to a single MSC.Translated from Kibernetika, No. 3, pp. 71–77, May–June, 1989.     

Functional connectivity between tRNA binding domains in glutaminyl-tRNA synthetase

The structure of Escherichia coli glutaminyl-tRNA synthetase (GlnRS) in complex with tRNAGln and ATP has identified a number a sequence-specific protein-tRNA interactions. The contribution to glutamine identity has previously been determined for the nucleotides in tRNAGln. Here, we report the mutational analysis of residues in all three tRNA recognition domains of GlnRS, thus completing a survey of the major sequence-specific contacts between GlnRS and tRNAGln. Specifically, we analyzed the GlnRS determinants involved in recognition of the anticodon which is essential for glutamine identity and in the communication of anticodon recognition to the acceptor binding domain in GlnRS. A combined in vivo and in vitro approach has demonstrated that Arg341, which makes a single sequence-specific hydrogen bond with U35 in the anticodon of tRNAGln, is involved in initial RNA recognition and is an important positive determinant for this base in both cognate and non- cognate tRNA contexts. However, Arg341, as well as Arg402, which interacts with G36 in the anticodon, are negative determinants for non-cognate nucleotides at their respective positions. Analysis of acceptor-anticodon binding double mutants and of a mutation of Glu323 in the loop-strand-helix connectivity subdomain in GlnRS has further implicated this domain in the functional communication of anticodon recognition. The better than expected activity (anticooperativity) of these double mutants has led us to propose an "anticodon-independent" mechanism, in which the removal of certain synthetase interactions with the anticodon eliminates structural constraints, thus allowing the relaxed specificity mutants in the acceptor binding domain ot make more productive interactions.