Understanding the phase relations and cation disorder in LRE1+xBa2− xCu3O7+δ

Unlike Y123 which forms only a stochiometric compound, the light rare earth elements (LRE) form a solid solution LRE_1+xBa_2-xCu₃O_7+δ (LRE123ss), with increasing substitution of the LRE³⁺ for the Ba²⁺ with increasing ionic radii of the LRE. Charge balance is maintained by increasing oxygen occupation on the anti-chain sites. The range of solubility is partially controlled by the oxygen partial pressure (PO₂). The peritetic decomposition temperature also increases with increasing ionic radii. At doping levels of 0 > × > 0.1, there is an increase in T_c when the high temperature annealing (T ∼ 940‡C) is performed in low PO₂ (> 0.1 bar). The maximum T_c occurs at a doping level of ∼x < 0.05 for Nd and Gd. When annealing is performed in 1 bar PO₂, there is a gradual decrease in T_c with increasing x. These phenomenon can be understood in terms of the number and distribution of the LRE which substitute on the Ba site.     

A multivariate model for the analysis of sibship covariance structure using marker information and multiple quantitative traits

The creation of a cross-link containing a disulfide into hemoglobin has been accomplished with a site-directed reagent, N,N'-bis(Cbz-cystinyl)bis(methyl phosphate) (1). This is prepared from the reaction of the bis acid chloride of N-protected cystine with dimethyl phosphate followed by O-demethylation with methyl iodide in acetone. Reaction with deoxyhemoglobin produces two main products: cross-linked hemoglobin as the bis(cystinyl amide) of the epsilon-amino group of the side chain of Lys-82 of the two beta subunits as well as material that has each of the same amino groups modified as the cysteinyl amide but not cross-linked. Addition of 2-mercaptoethanol cleaves the disulfide in the material that is not cross-linked while leaving the disulfide intact in the cross-linked species. Dithiothreitol reduces the disulfide in the cross-linked species as well as in the species that is not cross-linked. Spontaneous oxidation in air converts all of the reduced material to the cross-linked bis(cystinyl amide) of hemoglobin. The reagent permits controlled introduction of cystinyl groups at lysyl residues, leading to formation of sulfhydryl groups by reduction and the possibility of re-forming the cross-links or forming conjugates.     

Down-regulating effects of IL-4 and IL-10 on the IFN-gamma response in atopic dermatitis

Atopic dermatitis (AD) is a chronic allergic disease associated with toxin (superantigen)-producing Staphylococcus aureus skin infections, impaired delayed hypersensitivity responses, and the expansion of IL-4-secreting Th2 cells, as well as diminished IFN-gamma synthesis. IL-12 is known to induce IFN-gamma synthesis and to augment Th1 responses. In this study, therefore, we examined the potential role of IL-12 in the immunopathogenesis of AD. We show that, after stimulation with staphylococcal toxic shock syndrome toxin-1 (TSST-1) or IL-12, PBMC from patients with AD are deficient in their ability to produce IFN-gamma. PBMC from AD patients, however, produced normal quantities of IL-12 and expressed normal levels of IL-12R. Induction of IFN-gamma by TSST-1 was decreased by neutralizing anti-IL-12 Ab in normal donors, but not in AD patients. The latter observation is consistent with a defective response to IL-12 in AD PBMC. Because AD is associated with increased production of IL-4 and IL-10, we examined the effect of IL-4 on IL-12- or TSST-1-induced IFN-gamma production in normal donors. IL-4 inhibited IL-12-induced IFN-gamma production. Furthermore, Ab neutralization of IL-4 caused increased production of IFN-gamma in AD PBMC. However, neutralization of IL-10 activity caused an even greater augmentation of IFN-gamma production. Our data suggest that despite normal levels of IL-12 production and IL-12R expression, PBMC from AD patients are unable to generate normal IL-12-induced IFN-gamma responses. This defective response may be due to the excess production of IL-4 and IL-10 in this common allergic condition.     

Effects of infraorbital nerve section on survival, growth, and suckling behaviors of developing rats.

Examined the role of tactile sensory processes by surgical section of the infraorbital nerve in Wistar rats at 17, 12, 7, and less than 1 day of postnatal age. All sectioned Ss showed anesthesia of snout, upper lip, and vibrissal pads, and severe impairment of nipple attachment for at least the 1st day after denervation. Seven-day-olds failed to recover, and all died after 3–6 days of relentless weight loss. 17-day-olds showed no weight loss after denervation if already weaned to solid food, but they lost weight for 2 days before recovering if fed solely by nursing. 12-day-olds lost weight for 3 days, and 25% failed to recover. Behavioral observations showed that denervated Ss were activated by the mother's ventrum; they probed for the nipple in the appropriate area, but failed to focus head sweeping or licking and mouthing on the nipple itself. Data show that tactile cues are necessary for normal nursing in the rat and suggest that important tactile sensorimotor adaptations may occur during the early and late phases of nursing. (16 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

On naming a giraffe a zebra: Picture naming errors across different object categories.

Two experiments examined naming to deadline for picture of objects from categories with structurally similar or dissimilar exemplars. In Exp 1, a wider range of naming errors were made for objects from structurally similar categories, consistent with those items having a broader set of structural neighbors. Also, only visual?+?semantic errors were made to structurally similar objects, whereas modal errors for some structurally dissimilar objects were either purely visual or purely semantically related to targets. In Exp 2, the names of visual?+?semantic primes occurred as perseverative responses to objects from both category types. The data fit a cascade model of picture naming, in which errors under deadline reflect the rate-limiting processes affecting naming. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

DIS today [Distributed interactive simulation]

As the power and potential to create robust distributed interactive simulation (DIS) environments using the technical principles introduced by the SIMNET project gains recognition, the need for establishing standards for the implementation of these principles has grown dramatically. Initially, the interest in achieving interoperability between many disparate simulation components drove the work in developing standards. More recently, an equally important aspect for establishing standards has been to expand the market opportunities for simulation component suppliers. During the past five years, Workshops on Standards for the Interoperability of Distributed Simulations have provided the forum for establishing standards for networking dissimilar simulations to create virtual worlds in which many subjects can interact. These virtual worlds can be used for training individuals, testing equipment, prototyping products, research and development or any application involving the interaction of groups of people in a common synthetic environment     

Effect of hyperthermia on the radiosensitivity of normal and malignant cells in mice

The effect of systemic hyperthermia on the in vivo radiation response of normal and malignant mouse cells was evaluated. X-irradiation of L1210 cells and Ehrlich ascites cells at body temperatures above 41 degrees C resulted in strongly enhanced tumor cell death. The magnitude of this thermal effect increased with increasing temperatures. Hypoxic tumor cells were particularly sensitive to combined heat-radiation treatment. L1210 leukemia cells did not become resistant to the sensitizing effects of hyperthermia even after repeated heat exposures over several transplant generations. The sensitizing action of hyperthermia varied with different heating strategies. Heating before or during irradiation did not materially alter the radiation response of tumor cells. Maximal potentiation of radiation damage was achieved only when the tumorous mice were subjected to at least 20 minutes heat incubation after irradiation. LD studies on ICR mice revealed that moderate hyperthermia (41.5 degrees C) does not alter the radiation response of normal body tissues. These findings indicate that it is possible to devise hyperthermic treatment regimens that drastically enhance radiation-induced tumor cell death in vivo without reducing the radioresistance of normal tissues.     

When to separate uncertainties and when not to separate

A simple introductory example illustrates when to separate and when not to. The underlying principle is shown to also hold in situations of practical relevance. For several such situations it is discussed when, why and how to separate uncertainties. It is also pointed out how the outcome of this separation is used in practice.Subsequently the relation to the terms ‘epistemic’ and ‘aleatory’ is briefly explained.     

Developing standards for computerized psychological testing

The growth of computerized psychological testing (CPT) requires that we analyze its ethical and legal ramifications. The response of the legal community and the profession of psychology is reviewed. There are potential problems with the administration of tests by computer, especially the interpretation of computer-administered tests with norms and validity data from paper-and-pencil administrations, and the impact of computerization on certain test-taker groups and item types. Criteria for assessing the adequacy of classification systems used to assign people to interpretive statements, and the validity of computer-generated reports, are analyzed. CPT users should review reports and developers should disclose the rationale underlying interpretations. Not only the scientific merit, but also the fairness and efficiency of CPT will determine whether its potential is fully realized.