Improvement of microstructure and coercivity for Nd-Fe-B sintered magnets by boundary introducing low melting point alloys

Different from the grain boundary diffusion process(GBDP),which is suitable for modifying thin magnet,a green-pressing agents permeation process(GAPP) that uses low melting point alloys was applied to the Nd-Fe-B green compact with a thickness over 15 mm to reconstruct the boundary microstructure of a sintered Nd-Fe-B magnet.The coercivity increases from 12.3 kOe for the sample free of Pr_(80)Al_(20) to16.8 kOe for the sample with 2 wt% Pr_(80)Al_(20).By further increasing the Pr_(80)Al_(20) content to 3 wt%,the coercivity increases slightly,but the remanence and H_k/H_(cj) deteriorate obviously.The optimal comprehensive properties of H_(cj)=16.8 kOe,B_r=13.4 kG and H_k/H_(cj)=0.975 are obtained at 2 wt% Pr_(80)Al_(20),since matrix phase grains are separated by relatively continuous thin grain boundary layers,which weaken the magnetic coupling between adjacent grains.The coercivities of the samples from the GAPP that use2 wt% Pr_(80)Al_(20),Pr_(70)Al_(30) and Pr_(60)Tb_(20)Al_(20) alloys,respectively,can be enhanced to a large extent.However,the coercivity of the magnet reconstructed with Pr_(80)Al_(20) is lower than that of the sample with Pr_(60)Tb_(20)Al_(20) but is higher than that of the sample reconstructed with Pr_(70)Cu_(30) alloy.Moreover,the coercivity of the sample from the GAPP using 2 wt% Pr_(80)Al_(20) is much higher than that of the sample from the GBDP,which is due to a nearly uniform boundary microstructure from the surface to the interior of the thick magnet from the GAPP,thus providing new insights into the fabrication of thick and bulky permanent magnets with high coercivity.     

Communication of emotional intent by facial expression.

An experiment to: (a) ascertain the extent to which college students (expressors) can convey to other students (judges) via facial expressions alone, their emotional intent and (b) determine some correlates of this enactment ability. 50 expressors portrayed 10 emotions to 4 judges. Results: (a) The expressors were all able to enact recognizably at levels better than chance, but there were considerable individual differences in this ability. (b) Happiness, love, fear, and determination were more often accurately recognized than disgust, contempt, and suffering. (c) For these enactments, the Woodworth-Schlosberg scale was found to contain 5 rather than 6 categories and was not circular. (d) Contrary to expectation, no personality correlates of enactment ability were found. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Positive and negative reinforcement with short- and long-term hospitalized schizophrenics in a probability learning situation.

Groups of 40 long-term (LT) and 40 short-term (ST) schizophrenics were randomly assigned to positive (PR) and negative (NR) extrinsic reinforcement conditions during a probability learning task. Prior to experimental conditions, paper-and-pencil test measures of neuroticism, extroversion, paranoia, and process-reactive were administered. The results supported the major hypotheses that (a) ST schizophrenics are more responsive to PR than NR, (b) LT schizophrenics are more responsive to NR than PR, and (c) ST schizophrenics are more responsive to both PR and NR than LT schizophrenics. None of the correlations between personality variables and responsiveness to PR or NR were significant. The significant interaction between length of hospitalization and type of reinforcement was interpreted as reflecting schizophrenics' adjustment to the hospital environment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The development of a goal to become a teacher.

The purpose of this project was to investigate how the goal of becoming a teacher emerges. The study used interviews to develop goal histories for 8 preservice teachers. There tended to be 4 sources of influence for their goal to become a teacher: (a) family influences, (b) teacher influences, (c) peer influences, and (d) teaching experiences. The categories developed from the interviews to describe the types of influences those sources provided were (a) suggesting that the person become a teacher, (b) encouraging the person to become a teacher, (c) modeling teaching behavior, (d) exposing the person to teaching experiences, and (e) discouraging the person from becoming a teacher. In addition, influences such as critical incidents, emotions, and social-historical factors, such as the status and pay of teachers, were prominent in the goal histories of the participants. Finally, the results of the study are discussed within the context of goals and self-directed behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Rethinking shared environment as a source of variance underlying attention-deficit/hyperactivity disorder symptoms: Comment on Burt (2009).

Burt (2009) recently published a meta-analysis of twin studies on behaviors associated with childhood psychopathologies, concluding that the finding that traits associated with attention-deficit/hyperactivity disorder (ADHD) were the only behaviors that did not show a significant influence of shared environment (C) was surprising. We agree, highlighting four methodological issues that may account for this finding: (a) the use of nonlinear transformations to normalize skewed data; (b) low power to detect C and the subsequent presentation of reduced models; (c) the negative confounding of dominant genetic (D) and C influences in twin models with data exclusively from monozygotic and dizygotic twin pairs reared together; and (d) the correction used for contrast effects (a form of rater bias), which may lead to an overestimate of additive genetic (A) or D parameters at the expense of C. We offer suggestions for future research to address these issues, and we emphasize the need for additional research to examine possible shared environmental factors related to ADHD. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Juvenile transfer to adult courts: A look at the prototypes for dangerousness sophistication-maturity and amenability to treatment through a legal lens.

Juvenile court judges are often required to make distinctions as to whether certain adolescents should remain in the juvenile justice system or be transferred to adult courts. Typically, 3 broad factors weigh into juvenile court judges' decision making: (a) the level of danger the juvenile poses to the community, (b) the level of sophistication-maturity of the juvenile, and (c) the extent to which the juvenile is viewed as treatable. In an earlier study, knowledge of forensic and child psychologists was tapped to elucidate core characteristics related to the transfer process (R. T. Salekin et al, 2001). The current study augments that investigation. Judges provided (a) their perspective regarding the core criteria for dangerousness, sophistication-maturity, and amenability to treatment, and (b) data on the core characteristics of juveniles who were evaluated and subsequently judged to be appropriate for transfer to adult criminal courts. Policy implications for this increasingly critical interface between law and psychology are threefold: (a) Individualized assessments are key; (b) the adoption of a national standard for transfer to adult court is required; and (c) the development of treatment programs to improve the socialization of youth is necessary. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Dream reports and creative tendencies in students of the arts, sciences, and engineering.

105 students of arts, sciences, and engineering were asked to report a dream and to take a test which measures independence of judgment and relates to creativity. 4 predictions were stated: (a) (confirmed)—the proportion of dream recallers would be greatest among art students and least among engineering students; (b) (partially confirmed)—dream imaginativeness would be greatest among art students and least among engineering students; (c) (not confirmed)—dream recallers would have higher test scores than Ss who failed to recall a dream; (d) (confirmed)—there would be a positive relation between dream imaginativeness and test scores. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Increasing Substance Abuse Treatment Compliance for Persons With Traumatic Brain Injury.

This study compared 3 methods of increasing participation in substance abuse treatment for clients with traumatic brain injury. Participants (N = 195) were randomly assigned to 4 conditions: (a) motivational interview, (b) reduction of logistical barriers to attendance, (c) financial incentive, and (d) attention control. Four interviewers conducted structured, brief telephone interventions targeting the timeliness of signing an individualized service plan. Participants assigned to the barrier reduction (74%) and financial incentive (83%) groups were more likely to sign within 30 days compared with the motivational interview (45%) and attention control (45%) groups. Similar results were observed for time to signing, perfect attendance at appointments, and premature termination during the following 6 months. Extent of psychiatric symptoms was the only significant covariate. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Paving the Way for Public–Private Partnerships in Infrastructure Development

Infrastructure privatization has multidimensional impacts with long-term uncertainties and wide risk portfolios. A wide range of barriers to public–private partnerships (PPPs) in infrastructure development have been identified through a questionnaire survey, which are broadly classified into six aspects: (1) social, political, and legal risk; (2) unfavorable economic and commercial conditions; (3) inefficient public procurement framework; (4) lack of mature financial engineering techniques; (5) problems related to the public sector; and (6) problems related to the private sector. To explore measures for removing these barriers, a systematic research approach (literature review, case studies and interviews/correspondences with experts and experienced practitioners) has been taken to draw experience, learn lessons, and benchmark the best practices in international PPPs. An improved PPP protocol for infrastructure projects in general has been developed, addressing key issues in nine areas: (1) appropriate roles of governmental authorities; (2) best value for money approach; (3) effective management of adviser services; (4) formulation of appropriate PPP schemes; (5) use of relational contracts; (6) improvement of the procurement framework; (7) payment structure; (8) contract monitoring, termination, and step-in rights; and (9) transfer management. Effective measures for successful PPPs are identified in each of the nine areas.     

Triple-helical polynucleotides. Mixed triplexes of the poly(uridylic acid)-poly(adenylic acid)-poly(uridylic acid) class

By the techniques of interferon induction in primary rabbit kidney cells "superinduced" with metabolic inhibitors, ultraviolet absorbance-temperature profiles, sensitivity to pancreatic ribonuclease A, and sucrose velocity gradient ultracentrifugation, a number of reactions between double-helical RNA and single-stranded RNA or DNA homopolymers were investigated. The polymers involved in these studies were poly(adenylic acid), poly(uridylic acid), poly(ribothymidylic acid), poly(5-bromouridylic acid), poly(deoxythymidylic acid), poly(deoxyuridylic acid), poly(3-methyluridylic acid), poly(2'-O-methyluridylic acid), and poly(2'-azido-2'-deoxyuridylic acid). Two different reaction courses, both leading to the formation of triple helices, were noted: (1) poly(Ux)-poly(A) + poly(Uy) leads to poly(Ux)-poly(A)-poly(Uy) if the Tm of poly(Ux)-poly(A) was higher than the Tm of poly(Uy)-poly(A); (2) poly(Ux)-poly(A) + poly(Uy) leads to poly(Uy)-poly(A)-poly(Ux) if the Tm of poly(Ux)-poly(A) was lower than the Tm of poly(Uy)-poly(A). In these equations, the homopolymer written to the left of poly(A) implies Watson-Crick hydrogen bonding whereas the polymer to the right of poly(A) is involved in Hoogsteen hydrogen bonding.     

Aspects of health education connected with the process of preparing for old age (author''s transl)]

Bilirubin kinetics were studied in an isolated, perfused rat liver system using unconjugated (14C) bilirubin (UC(14C)B) and delta-amino (4-14 C) levulinic acid (A(14 C)LA) to derive a suitable compartmental model. Plasma disappearance of UC(14C)B, plasma appearance of conjugated (14c) bilirubin (C(14C)B) and biliary excretion of C(14C)B were followed for 90-120 min following injection of UC(14C)B. Hepatic content of labeled bilirubin 12 min after the injection of UC(14C)B was determined directly in five separate perfusion experiments. UCB was found to reflux back to plasma from liver in two experiments using A(14C)LA. Bilirubin binding to red blood cells (6-8% of the perfusate level) and the components of the perfusion apparatus (4-6% of perfusate level) was estimated by performing a control experiment without the liver. A six compartment model was necessary and adequate to explain the experimental data and current knowledge of bilirubin metabolism: (1) UCB bound to red blood cells and the perfusion apparatus, (2) plasma UCB, (3) liver UCB, (4) liver CB, (5) plasma CB, and (6) bile CB. The proposed model could serve as a reference point for studies of bilirubin kinetics in whole animals for normal and abnormal states.     

The role of dorsal hippocampus and basolateral amygdala NMDA receptors in the acquisition and retrieval of context and contextual fear memories.

The authors used 3-phase context preexposure facilitation methodology to study the contribution of N-methyl-D-aspartate (NMDA) receptors in dorsal hippocampus (DH) and the basal lateral region of the amygdala (BLA) to (a) acquisition of the context memory, (b) retrieval of the context memory, (c) acquisition of context-shock association, and (d) retrieval of the context-shock association. The NMDA receptor antagonist D-2-amino-5 phosphonopentanoic acid (D-AP5) was injected into either the DH or BLA prior to (a) the context preexposure phase, (b) the immediate shock phase, or (c) the test for contextual fear. Antagonizing NMDA receptors in the DH impaired the acquisition of the context memory but did not affect its retrieval or retrieval of the fear memory. Antagonizing NMDA receptors with D-AP5 in the BLA impaired acquisition of the context-shock association but had no effect on the expression of fear. However, both DL-AP5 and L-AP5 reduced the expression of fear when they were injected into the amygdala prior to testing for contextual fear. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Real–Time Speciation of Uranium during Active Bioremediation and U(IV) Reoxidation

The biological reduction of uranium from soluble U(VI) to insoluble U(IV) has shown potential to prevent uranium migration in groundwater. To gain insight into the extent of uranium reduction that can occur during biostimulation and to what degree U(IV) reoxidation will occur under field relevant conditions after biostimulation is terminated, X-ray absorption near edge structure (XANES) spectroscopy was used to monitor: (1) uranium speciation in situ in a flowing column while active reduction was occurring; and (2) in situ postbiostimulation uranium stability and speciation when exposed to incoming oxic water. Results show that after 70 days of bioreduction in a high (30?mM) bicarbonate solution, the majority (>90%) of the uranium in the column was immobilized as U(IV). After acetate addition was terminated and oxic water entered the column, in situ real-time XANES analysis showed that U(IV) reoxidation to U(VI) (and subsequent remobilization) occurred rapidly (on the order of minutes) within the reach of the oxygen front and the spatial and temporal XANES spectra captured during reoxidation allowed for real-time uranium reoxidation rates to be calculated.     

Bioreduction of Hexavalent Chromium in Flow-Through Quartz Sand Columns

Hexavalent chromium (Cr(VI)) contamination of soil and groundwater is a major environmental concern for some industrial sites and most of the U.S. Department of Energy sites. Cr(VI) is toxic and fairly mobile in groundwater. Bioreduction of Cr(VI) to less toxic and less mobile Cr(III) is considered to be a feasible option. Among the Cr(VI) reducing bacteria, Shewanella oneidensis MR-1 (MR-1) has been shown to be effective in metal reduction under anaerobic conditions. Data on bioreduction of Cr(VI) by MR-1 in a flow-through soil column that better approximates the subsurface condition are not available. The objective of this research project was to study the bioreduction of Cr(VI) by MR-1 in a continuous-flow quartz sand column system. MR-1 was found to be very effective in reducing Cr(VI) to Cr(III) for concentrations ranging from 0.055 mM (2.85?mg/L) to 0.006 mM (0.31?mg/L). The amount of Cr(VI) reduced prior to its breakthrough was found to be inversely proportional to its concentration in the feed due to increased inhibition of microbial activity and a residual reduction of 20–45% of Cr(VI) was observed even after its breakthrough.     

Surface-effect on detection ability of fluorescent Eu(btc) metal-organic frameworks to metal ions

Eu(btc)metal organic frameworks(MOFs)were prepared by co-precipitation method via 1,2,4-benzenetricarboxylic acids(H3btc)connecting with Eu³⁺ions,and the morphology was controlled from compact spherical to irregular honeycomb by adjusting the pH of reaction solutions.The luminescence properties of Eu(btc)MOFs are found to be related to the surface morphology of products,and the compact spherical one performs stronger emission intensity.The sensing ability of Eu(btc)MOFs to 11 kinds of metal ions was investigated and a prominent quenching effect occurrs in Fe³⁺,or Ni²⁺solutions.Based on UV—vis absorption analysis,an“ion-fence”model presents the competition to absorb exciting light between Eu(btc)MOFs and adsorbed metal ions.Based on Stern-Volmer equation,the Eu(btc)detection is found with higher Ksv value and a lower detection limit.Meanwhile,a higher sensing efficiency is confirmed in the Eu(btc)MOFs with loose honeycomb due to aggravating porous surface offering much more sites for metal ions.     

Enrichment process of lanthanum as a nonessential trace element in leaf cells of lettuce (Lactuca sativa L.)

Rare earth elements (REEs) as nonessential trace elements are enriched in living organisms and threaten their health. To early detect and reduce REE enrichment in living organisms, scientists are focused on clarifying the enrichment process of REEs in living organisms and its risks. However, the enrichment process of REEs in edible plant cells has remained unclear. Herein, by using interdisciplinary methods and techniques, the enrichment process of lanthanum (La(III)) in the leaf cells of lettuce (Lactuca sativa L.) was investigated. (1) When La(III) exposure dose is 0.5–5 μmol/L, La(III) is enriched outside the plasma membrane (PM). In this zone, La(III) is bound to vitronectin-like protein (VN) to form La–VN complexes; (2) When La(III) exposure dose is 5–20 μmol/L, besides the zone outside the PM, La(III) is also enriched on the PM and bound to arabinogalactan proteins (AGPs) to form La–AGPs complexes; (3) When La(III) exposure dose is 20–140 μmol/L, besides the zone outside and on the PM, La(III) is enriched inside the PM; (4) When La(III) exposure dose is 60–140 μmol/L, malondialdehyde content (an important indicator of invisible damage) significantly increases. Thus, as La(III) exposure dose increases, La(III) gradually migrates from outside the PM to the PM and inside the PM, enriching in these zones in turn. The enriched La(III) will cause invisible damage to lettuce leaf cells and even enter human bodies along food chains. These results provide references for investigating the enrichment process of REEs in plants and its environmental risks, and finding strategies to early detect and reduce REE enrichment in plants.     

Fear of failure, achievement motivation, and aspiring to prestigeful occupations.

From a list of 40 occupations, 67 male undergraduates were asked (a) which occupation was nearest the one they intended to strive for, (b) what satisfaction could be expected from each occupation listed, (c) which were realistically attainable, and (d) which would they settle for if the stress of occupational achievement could be avoided. As fear of failure (FF) increased (a) the prestige of aspired-to occupations decreased, (b) willingness to settle for less satisfying and less prestigeful occupations increased, and (c) the person became more likely to perceive that occupations with extremely low probabilities of attainment were within his reach. Effects of achievement motivation were very weak but generally in a direction opposite to that of FF. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Chemistry of urinary mannosides excreted in mannosidosis

Mannose-rich oligosaccharides have been isolated from urines of 5 patients with mannosidosis. Their compositon and structure were determined. Three of them have been previously described by Norden et al: alpha p-Manp-(1 leads to 3) beta-d-Manp-(1 leads to 4) d-GlcNAcp; alpha-p-Manp-(1 leads to 2), alpha-d-Manp-(1 leads to 3) beta-d-Manp-(1 leads to 4) d-GlcNAc and alpha-d-Manp-(1 leads to 2) alpha-d-Manp-(1 leads to 2) alpha-d-Manp-(1 leads to 3) beta-d-Manp-(1 leads to 4) d-GlcNAcp, but the four others are new entities: alpha-d-Manp-(1 leads to 3) (alpha-d-Manp-(1 leads to 2) alpha-d-Manp-(1 leads to 2) alpha-d-Manp-(1 leads to 6) beta-d-Manp-(1 leads to 4) GlcNAcp; alpha-d-Manp-(1 leads to 2) alpha-d-Manp-(1 leads to 3) (alpha-d-Manp-(1 leads to 2) alpha-d-Manp-(1 leads to 6) beta-d-Manp-(1 leads to 4) GlcNAcp; alpha-d-Manp-(1 leads to 2), alpha-d-Man-(1 leads to 3) (alpha-d-Manp-(1 leads to 6) beta-d-Manp-(1 leads to 4) GlcNAp and alpha-d-Manp-(1 leads to 2) alpha-d-Manp-(1 leads to 3) (alpha-d-Manp-(1 leads to 6) beta-d-Manp-(1 leads to 4) GlcNAcp. These structures are related to the glycans of "oligomannosidic type" present in numerous glycoproteins. All possess a N-acetylglucosamine residue in terminal reducing position and reinforce the hypothesis of Kobata et al. and Montreuil et al. that catabolism of glycans N-glucosidically linked to the protein moiety begins by the aciton of a beta-endo-N-acetylglucosaminidase.     

Topography of spatially directed conditioned responding: Effects of context and trial duration.

Domesticated quail (Coturnix japonica) received a discrete conditioned stimulus (CS) at one end of the experimental chamber paired with the opportunity to copulate with a female quail (the unconditioned stimulus) in a goal box located 112 cm away. Approach to the CS (sign tracking) and approach to the goal area (goal tracking) were measured. The duration of exposure to the experimental context (C) was varied in Experiment 1, and the duration of the conditioning trials (T) was varied in Experiment 2 for independent groups, creating C/T ratios of 1.0, 1.5, 4.5, 45, and 180. Contrary to previous reports of a direct relation between the C/T ratio and conditioned responding, in the present experiments, a shift in the topography and stimulus control of conditioned behavior occurred. Low C/T ratios (1.0–4.5) produced goal tracking controlled by contextual cues, whereas high C/T ratios (45 and 180) produced sign tracking controlled by the discrete CS. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Fictions and Facts About Evolutionary Approaches to Human Behavior: Comment on Lickliter and Honeycutt (2003).

Six misconceptions about evolutionary approaches to human behavior are exposed. Evidence is adduced to support the assertions that evolutionary approaches do not (a) adopt a reductionistic "gene-centered" level of analysis, (b) assume that natural selection is the only process that creates and designs ontogenetic processes and phenotypic outcomes, (c) assume that genes are the only agents responsible for the transgenerational inheritance of phenotypic traits and characteristics, (d) assume that genes are self-contained and impervious to extragenetic influences, (e) posit a strong form of genetic determinism, or (f) pay lip service to the role of the environment. Building straw men and knocking them down is an inherently destructive enterprise; integrating different approaches is a more constructive way of contributing to the growth of knowledge. (PsycINFO Database Record (c) 2010 APA, all rights reserved)