Two component hydrogels

Summary This and the subsequent papers concern with two component hydrogels, consisting of a polymer backbone built up by one polymer component, which is crosslinked by bridges of another polymer with varying length. In order to understand the effects of the crosslinker chain length on the networks as a whole the thermodynamic interaction parameters for the system, with special reference to the swelling behaviour, have to be determined first. By adapting and extending Sakurada' s method the equations of state for the ternary system waterlinear crosslinker- one component gel are developped first.     

Setting an uncorrected visual acuity standard for police officer applicants

The Madelung deformity can result in pain and decreased function of the wrist and hand. None of the surgical techniques available has been shown consistently to improve grip strength, range of movement or relieve pain. In this prospective study we have treated 18 patients with the Madelung deformity (25 wrists) by wedge subtraction osteotomy of the radius and shortening of the ulna. Our results show statistically significant improvement in grip strength and range of movement of the wrist and forearm. Pain improved in 80% of the patients and 88% were satisfied with the appearance. One patient had a wound infection and another developed reflex sympathetic dystrophy. Two had some recurrence due to continued growth of the ulna and it is recommended that the procedure be delayed until skeletal maturity, or else combined with epiphysiodesis of the ulna.     

Schools make a difference: Evidence, criticism, and new directions.

Examines recent research on school effectiveness and emphasizes how variation in school processes affect student achievement. Although the review indicates that there is meaningful variation across schools in student achievement, it is argued that there are conceptual and methodological limitations of the research, such as its atheoretical nature and the instability of outcomes, that must be considered when findings are used for policy and program development. New directions for school research are discussed, including the need to study a wide range of student outcomes other than student performance on standardized achievement tests and the need to identify how classroom and school processes combine to create an effective learning environment. (29 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

An increase in basal glucocorticoid concentration with age induces suppressor macrophages with high-density Fc gamma RII/III

BACKGROUND: The diagnosis of Tourette syndrome may be overlooked in patients with severe psychopathologic disorder but mild motor manifestations of Tourette syndrome. OBJECTIVE: To describe 4 patients with long-lasting general psychopathologic disorder and previously unrecognized mild motor and phonic tics exacerbated during adulthood by the onset of tremor; all of the patients had been referred for the evaluation of psychogenic tremor. SUBJECTS: Four adult patients, with previous psychiatric diagnoses of depression (2 cases), generalized anxiety disorder (3 cases), malingering (1 case), and conversion disorder (3 cases). METHODS: Single case studies. RESULTS: Clinical interviews disclosed that the 4 patients had positive family histories of Tourette syndrome, and all had mild motor and phonic tics that had started before the age of 18 years. On neurologic examination, 2 patients had bilateral postural tremor of the hands that varied in frequency, rhythmicity, and amplitude, and the other 2 had resting tremor mimicking parkinsonism. All 4 patients described involuntary somatic sensations of the affected limbs, which they attempted to alleviate by executing movements. No consistent positive placebo response was observed, but in all patients tremoric movements improved with haloperidol. CONCLUSIONS: These cases illustrate an unusual movement disorder (tremor as a "tic equivalent") in adults with Tourette syndrome and emphasize that cases of the syndrome with mild tics often go unrecognized, precluding adequate treatment.     

Differential effects of ibotenic acid lesions of the hippocampus and blockade of N-methyl-D-aspartate receptor-dependent long-term potentiation on contextual processing in rats

The contextual specificity of appetitive conditioned responding was examined in rats undergoing chronic intracerebroventricular infusion of 15 or 30 mM D-2-amino-5-phosphonopentanoic acid (D-AP5) or with excitotoxic hippocampal lesions. The magnitude of conditioned responding by control rats and rats infused with D-AP5 to a conditioned stimulus (CS) trained in Context A was attenuated when the same stimulus was presented in Context B. By contrast, hippocampal-lesioned rats displayed comparable levels of responding to the CS when presented in either Context A or B. Subsequent in vivo electrophysiological investigations showed that the D-AP5 concentrations were effective in blocking long-term potentiation (LTP) in the dentate gyrus. Results indicate that rats are capable of processing contextual information in the absence of N-methyl-D-aspartate (NMDA) receptor-dependent LTP and demonstrate an important dissociation between the effects of hippocampal lesions and the blockade of NMDA receptors in the hippocampus.     

Male gender role conflict: Psychometric issues and relations to psychological distress.

Two distinct deficits in research on male gender role conflict are addressed: (a) lack of psychometric information and (b) lack of research involving clinical samples. First, using 1,043 men across 3 samples, the psychometric properties of the Gender Role Conflict Scale (GRCS) were examined through confirmatory factor analyses, internal consistency estimation, and construct validation. Next, using 130 male university counseling center clients across 2 samples, the relation between gender role conflict and psychological distress was examined. The GRCS demonstrated good internal consistency and was best modeled as 4 intercorrelated factors, as originally proposed by J. M. O'Neil, B. Helms, R. Gable, L. David, and L. Wrightsman (1986). Construct validity was supported through correlations with attitudes about masculinity, fear of intimacy, and social desirability in expected directions. However, reservations about the Conflicts Between Work and Family Relations subscale are noted. Male gender role conflict was significantly related to psychological distress, with the Restrictive Emotionality subscale being the best predictor of distress level. Implications for mental health practice and future research are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Assessment for instructional decisions: Toward a proactive/prevention model of decision-making for early literacy skills.

Uses a case study to illustrate a problem solving model of educational decision making using Dynamic Indicators of Basic Early Literacy Skills (DIBELS) measures to provide a local normative context, to monitor progress, and to evaluate the effects of interventions on an individual basis. The linkage between assessment information and educational decisions is demonstrated in the 4 phases of the problem solving model: Problem Identification, Problem Validation, Exploring Solutions, and Evaluating Solutions. For the case study, the problem solving model using DIBELS measures of phonological awareness provided important information regarding who to target for intervention, what skill to target in the intervention, and which interventions were effective. Using DIBELS measures of early literacy skills, educators can intervene early to prevent serious reading difficulties later. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Integration of geometric with luminance information in the rat: Evidence from within-compound associations.

In two experiments, rats first received preexposure to a rectangular arena in which the geometrically equivalent corner pairs (G1 and G2) were coincident with different luminance characteristics (C1 and C2, respectively). In Experiment 1, rats were then placed in a uniform gray rectangular arena where food was located in one geometrically equivalent pair of corners (G1), but not another (G2). Finally, rats were tested in a square arena with C1 and C2 and preferred to search in C1 rather than C2. In Experiment 2, following preexposure to G1C1 and G2C2, rats received pairings of C1 with food and C2 with no food in a square arena. During testing, rats preferred to search in G1 rather than G2 in a gray rectangular arena. These results demonstrate that reciprocal within-compound associations develop between geometric and luminance information and thereby challenge the view that there is a dedicated geometric module that is impenetrable to information that is not geometric. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Analytically predicted versus measured response of a free-standing steel containment vessel subjected to safety-relief valve discharge loads

Following the actuation of safety-relief valves in BWR nuclear power plants, first water then air and steam are cleared from the discharge lines through quencher devices into a suppression pool. This clearing results in water spike, air bubble, and condensation pressure loads applied to structures in the pool, and the surrounding containment vessel.The Leibstadt Nuclear Power Plant has the only free-standing steel Mark III containment vessel in the world. All other steel Mark III containment vessels have concrete backing in the suppression pool region, which dampens clearing load responses. As such, it is of interest to note how this steel vessel responds to discharge pressures, and compare these responses to analytically predicted results.The purpose of this paper is to compare the analytical results used to design the steel containment vessel with the responses measured during in-plant testing. The analytical methods considered the effects of fluid-structure interaction. The test program included initial and consecutive actuations of a single valve, and initial actuation of multiple (four) valves. The conclusion of the comparison is that, in general, there are large conservatisms in the analytical predictions versus measured responses.