Instrumented capsule for in-reactor fuel creep studies at high fission rates

An instrumented capsule for in-reactor creep studies of ceramic nuclear fuels at high fission rates has been designed, fabricated and succesfully operated. The capsule contains a device for loading the creep specimen in compression from 0 to 13,000 psi. The temperature is adjusted by means of both internal electrical heaters and a gas gap. The deformation of the specimen during creep is continuously measured by means of a constant gas flow, variable orifice device.Creep studies have been conducted in the Battelle Research Reactor on UO₂-22 w/o PuO₂ in the temperature range of 350 to 600°C, the stress range of 4000 to 8000 psi and the fission rate of 3.8 × 10¹³ fissions/cm³ sec. The creep rate under these conditions was found to be substantially increased as a result of the fission process.     

Scientific and practical advantages of comparative design in psychotherapy outcome research.

Examination of the scientific basis of both control group designs and comparative designs (CDs) in outcome research reveals that CDs generally have fewer threats to validity and provide a more efficient means of control for nonspecific treatment factors. Added to the ethical and practical advantages of CDs, these scientific advantages indicate that CD studies warrant a larger role in the study of psychotherapy, particularly in evaluative research. Research strategies utilizing CDs are described, and some implications of the use of comparative methodology for the researcher–practitioner split in clinical psychology are discussed. (43 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A massively multi-scale approach to characterizing tissue architecture by synchrotron micro-CT applied to the human placenta

Multi-scale structural assessment of biological soft tissue is challenging but essential to gain insight into structure–function relationships of tissue/organ. Using the human placenta as an example, this study brings together sophisticated sample preparation protocols, advanced imaging and robust, validated machine-learning segmentation techniques to provide the first massively multi-scale and multi-domain information that enables detailed morphological and functional analyses of both maternal and fetal placental domains. Finally, we quantify the scale-dependent error in morphological metrics of heterogeneous placental tissue, estimating the minimal tissue scale needed in extracting meaningful biological data. The developed protocol is beneficial for high-throughput investigation of structure–function relationships in both normal and diseased placentas, allowing us to optimize therapeutic approaches for pathological pregnancies. In addition, the methodology presented is applicable in the characterization of tissue architecture and physiological behaviours of other complex organs with similarity to the placenta, where an exchange barrier possesses circulating vascular and avascular fluid spaces.     

A simple, quantitative, reproducible avidin-biotin ELISA for the evaluation of group B streptococcus type-specific antibodies in humans

Type-specific antibodies to the capsular polysaccharides (CP) of group B Streptococcus (GBS) are protective. Historically, the radioactive antigen-binding assay (RABA) has been used to determine GBS antibody levels. This method measures total immunoglobulin and employs the use of radioactive materials. We have developed an avidin-biotin ELISA that is less hazardous and is able to measure GBS Ia, Ib, II or III CP specific IgG. To avoid inconsistent binding to the plate, the CPs from GBS Ia, Ib, II and III were derivatized using adipic acid dihydrazide (ADH) and subsequently biotinylated without altering their antigenic epitopes and bound to avidin coated plates. Plasma from three different human subjects immunized with a tetravalent CP vaccine were used to prepare IgG references for Ia, II and III, respectively, thus rendering the assay quantitative for those types. The assay is able to detect nanograms per milliliter of GBS Ia, Ib, II or III specific antibody. This method is reproducible, sensitive and correlates with RABA by 76%.     

Assessing social support: The Social Support Questionnaire.

Describes the Social Support Questionnaire (SSQ) and 4 empirical studies employing it. The SSQ yields scores for (a) perceived number of social supports and (b) satisfaction with social support that is available. Three studies (N?=?1,224 college students) dealt with the SSQ's psychometric properties, its correlations with measures of personality and adjustment, and the relation of the SSQ to positive and negative life changes. The 4th study (40 Ss) was an investigation of the relation between social support and persistence in working on a complex, frustrating task. The research reported suggests that the SSQ is a reliable instrument and that social support is (a) more strongly related to positive than negative life changes, (b) more related in a negative direction to psychological discomfort among women than men, and (c) an asset in enabling a person to persist at a task under frustrating conditions. Clinical implications are discussed. (47 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The intrinsic structure and stability of out-of-alternation base pairs in Z-DNA

The inv(16) and related t(16;16) are found in 10% of all cases with de novo acute myeloid leukemia. In these rearrangements the core binding factor beta (CBFB) gene on 16q22 is fused to the smooth muscle myosin heavy chain gene (MYH11) on 16p13. To gain insight into the mechanisms causing the inv(16) we have analysed 24 genomic CBFB-MYH11 breakpoints. All breakpoints in CBFB are located in a 15-Kb intron. More than 50% of the sequenced 6.2 Kb of this intron consists of human repetitive elements. Twenty-one of the 24 breakpoints in MYH11 are located in a 370-bp intron. The remaining three breakpoints in MYH11 are located more upstream. The localization of three breakpoints adjacent to a V(D)J recombinase signal sequence in MYH11 suggests a V(D)J recombinase-mediated rearrangement in these cases. V(D)J recombinase-associated characteristics (small nucleotide deletions and insertions of random nucleotides) were detected in six other cases. CBFB and MYH11 duplications were detected in four of six cases tested.     

Clinical utility of the MMPI research scales in the assessment of adolescent acting out behaviors.

The substantial number of MMPI research scales developed during the last 50 yrs provides a unique opportunity to compare the practical value of a large number of related scales and the methodologies used to develop them. To this end, the concurrent validity of 93 MMPI scales as measures of acting out (aggressiveness, chemical dependency, delinquency, family conflict, and school behavior problems) was evaluated in a sample of 327 adolescent inpatients. Results generally support the construct validity of the Psychopathic Deviate scale but also reveal several research scales that function well as broad measures of acting out. There were, however, relatively few scales that were narrowly related to specific behavioral tendencies. Scales consisting exclusively of face-valid items generally performed better in this regard than did scales including "subtle" items, and they appear to have greater clinical utility with this population. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Antigenic determinants of Staphylococcus aureus type 5 and type 8 capsular polysaccharide vaccines

Bacterial capsular polysaccharides (CP) are carbohydrate polymers comprised of repeating saccharide units. Several of these CP have side chains attached to their backbone structures. The side chains may include O-acetyl, phosphate, sialic acid, and other moieties. Those moieties represent the immunodominant epitopes and the most functional ones. The clinically significant Staphylococcus aureus type 5 CP (CP 5) and type 8 CP (CP 8) are comprised of a trisaccharide repeat unit with one O-acetyl group attached to each repeat unit. The immunogenicity of these CP and the functionality of antibodies to the backbone and the O-acetyl moieties were investigated. Immunization with the native CP conjugates (CP with 75% O-acetylation) elicited a high proportion of antibodies directed against the O-acetyl moiety. Nonetheless, all of the vaccinees produced antibodies to the backbone moieties as well. Conjugate vaccines made of de-O-acetylated CP elicited backbone antibodies only. Antibodies to both backbone and O-acetyl groups were found to be opsonic against S. aureus strains which varied in their O-acetyl content. Absorption studies with O-acetylated and de-O-acetylated CP showed that (i) native CP conjugates generated antibodies to both backbone and O-acetyl groups and (ii) O-acetylated isolates were opsonized by both populations of antibodies while the non-O-acetylated strains were predominantly opsonized by the backbone antibodies. These results suggest that S. aureus CP conjugate vaccines elicit multiple populations of antibodies with diverse specificities. Moreover, the antibodies of different specificities (backbone or O-acetyl) are all functional and efficient against the variations in bacterial CP that may occur among clinically significant S. aureus pathogenic isolates.     

The Watcombe housing study: the short-term effect of improving housing conditions on the indoor environment

A three-year study (1999-2001) was initiated in the UK to assess the effect of improving housing conditions in 3-4 bedroom, single-family unit, social rented sector houses on the health of the occupants. The houses were randomised into two groups. Phase I houses received extensive upgrading including wet central heating, on demand ventilation, double-glazed doors, cavity wall and roof/loft insulation. An identical intervention for Phase II houses was delayed for one year. As part of this randomised waiting list study, discrete measurements were made of indoor environmental variables in each house, to assess the short-term effects of improving housing conditions on the indoor environment. Variables representative of indoor environmental conditions were measured in the living room, bedroom and outdoors in each of the three years of the study. In 2000, there was a significant difference between the changes from 1999 to 2000 between Phase I (upgraded) and II (not then upgraded) houses for bedroom temperatures (p=0.002). Changes in wall surface dampness and wall dampness in Phase I houses were also significantly different to the change in Phase II houses in 2000 (p=0.001), but by 2001 the Phase I houses had reverted to the same dampness levels they had before upgrading. The housing upgrades increased bedroom temperatures in all houses. Other indoor environmental variables were not affected.