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Repeated formation and subsequent dissolution of romantic relationships is common in humans across a lifetime. The socially monogamous prairie vole (Microtus ochrogaster) is used to study mechanisms of these bonds. At least in the laboratory, male prairie voles form bonds with a new female partner after loss of a previous partner. Initial bond formation depends on activation of dopamine D2-like receptors in the nucleus accumbens. Blocking activity of this receptor subtype disrupts formation of an animal's first pair bond. It is not known if these same D2-like receptors facilitate pair bonding with a subsequent partner after previous partner loss. This study examined the effects of D2-like receptor blockade on repeated pair bonding in male prairie voles. Males were paired with an initial female and allowed to mate before being separated. After a 5-day separation, males were then treated with either saline or eticlopride, a selective D2-receptor antagonist, prior to being paired with a second female and being allowed to mate. After a second separation, males were tested to determine if they developed a preference for spending time with their first or second mate. Eticlopride-treated males spent more time in a cage containing one of their previous partners compared to time in an empty cage but did not form a selective preference for either partner. Saline-treated males preferred their second, more recent partner. D2 receptor antagonism, then, disrupts bond formation in a second pairing but does not help to maintain a bond with the initial partner.

USE OF THE VERBAL REINFORCEMENT TECHNIQUE (VRT) IN DEVELOPMENTAL, PERSONALITY, AND SOCIALIZATION STUDIES OFTEN RESTS ON TENUOUS AND UNTESTED ASSUMPTIONS. THIS STUDY EXAMINED FIVE VARIABLES WHICH HYPOTHETICALLY RELATE TO PERFORMANCE UNDER REINFORCEMENT--SELF-ESTEEM OF S. TASK-INVOLVEMENT, EXPERIMENTER, ORDINAL POSITION, AND FAMILY SIZE. THE METHOD CONTROLLED AGAINST INFORMATIONAL ADVANTAGES FOR THE NEGATIVE OR POSITIVE REINFORCEMENT CONDITIONS. SS WERE COLLEGE MALES. POSTEXPERIMENTAL DATA (FROM AN INTERVIEW) INDICATED INDUCTION OF ALL THE MPUTED VARIABLES. RESULTS WERE THAT VR HAD A MAIN EFFECT ON PERFORMANCE (DIGIT-SYMBOL TASK). NEGATIVE REINFORCEMENT WAS SUPERIOR TO BOTH POSITIVE REINFORCEMENT AND TO NONEVALUATIVE INSTRUCTIONS, SUGGESTING A PSYCHOLOGICAL DIFFERENCE BETWEEN CRITICISM AND PRAISE. LOW SELF-ESTEEM SS IMPROVED MORE UNDER CRITICISM THAN DID HIGH SELF-ESTEEM SS. THE ONLY OTHER VARIABLE INTERACTING WITH REINFORCEMENT WAS FAMILY SIZE. SAMLL-FAMILY SS RESPONDED MORE TO REINFORCEMENT PER SE AND SPECIFICALLY TO POSITIVE REINFORCEMENT THAN LARGE-FAMILY SS. THIS FINDING APPEARS INCONSISTENT WITH THE SATIATION HYPOTHESIS. FAILURE OF OTHER VARIABLES TO INTERACT WITH VR, IN SPITE OF EVIDENCE THAT THESE VARIABLES WERE SUCCESSFULLY MANIPULATED, SUGGESTS THE ASSUMPTIONS OF MUCH VR RESEARCH NEED MORE DIRECT TESTING. (AUTHOR)

Dietary supplements are widely used to enhance sport performance and the combination of carbohydrate and caffeine (CHO+CAF) has yielded particularly high performance gains. Though the effects of a CHO+CAF supplement have been studied in a laboratory environment, little research exists on the effects of supplementation during competition. Therefore, the purpose of this study was to determine the effects of a CHO+CAF supplement on athletic performance in competition. Eight female collegiate volleyball players completed three testing sessions under three different conditions separated by approximately one week each: CHO+CAF supplement, placebo (PBO), and control (CTL) using a randomized, cross-over design. Blood glucose (BG) was assessed prior to supplementation and immediately after set three. The supplement and PBO were administered prior to play and between sets two and three. Following three sets of play, three performance tests were completed: vertical jump (VJ), agility (AGL), and repeated 30-m sprint ability (RSA). While CHO+CAF supplementation significantly increased BG, the performance tests were not different (p>.05) among the testing conditions. These findings suggest that the amount of the supplement used in this study is not beneficial to VJ, AGL, and RSA in female volleyball players. As these performance tests were largely anaerobic and non-glycolytic in nature, the ergogenicity of the supplement may have been underutilized. Additionally, coaches and athletes should not only be aware of what ingredients are in the supplements they choose, but the amount of those ingredients as they may modify the efficacy of the supplement to impact performance.

rice (Oryza sativa L.) is one of the most impor - tant staple food crops. Its cultivation requires a relatively high input of N fertilizers; however, rice plants do not absorb a significant proportion of added fertilizers, resulting in soil and water pol - lution. The use of diazotrophic (N-fixing) endo - phytes can provide benefits for rice cultivation by reducing the demand of N fertilizers. Diazo - trophic endophytes from the early successional plant species poplar ( Populus trichocarpa Torr. & A. Gray) and willow ( Salix sitchensis C. A. San- son ex Bong.) were added to rice seedlings. Inoculated rice plants were grown in N-limited conditions in the greenhouse, and plant physical characteristics were assessed. Endophyte-inoc - ulated rice plants had greater biomass, higher tiller numbers, and taller plant stature than mock- inoculated controls. Endophyte populations were quantified and visualized in planta within rice plants using fluorescent microscopy. The endo - phytes colonized rice plants effectively in both roots and foliage. These results demonstrated that diazotrophic endophytes of the eudicots poplar and willow can colonize rice plants and enhance plant growth in N-limited conditions.

The purpose of this article is to propose a community structural intervention for low-income families who present to therapy with the concern of an adolescent at risk for gang involvement. Families are affected by multiple interacting systems. In congruence with systems theory, changing a part of the system will essentially affect the interrelated parts of the system. The proposed intervention utilizes structural family therapy and community family therapy as a model to impact change at the family system, its interrelated systems, and the system at which the family is embedded.

Summary Background Benign lichenoid keratoses (BLKs) are solitary skin lesions which have been proposed to represent a regressive form of pre-existent epidermal tumours such as solar lentigo or seborrhoeic keratosis. However, the genetic basis of BLK is unknown. Objectives FGFR3, PIK3CA and RAS mutations have been shown to be involved in the pathogenesis of seborrhoeic keratosis and solar lentigo. We thus investigated whether these mutations are also present in BLK. Methods After manual microdissection and DNA isolation, 52 BLKs were screened for FGFR3, PIK3CA and RAS hotspot mutations using SNaPshot® multiplex assays. Results We identified 6/52 (12%) FGFR3 mutations, 10/52 (19%) PIK3CA mutations, 6/52 (12%) HRAS mutations and 2/52 (4%) KRAS mutations. FGFR3 and RAS mutations were mutually exclusive. One BLK showed a simultaneous PIK3CA and HRAS mutation. In nine BLKs with a mutation, nonlesional control tissue from the epidermal margin and the dermal lymphocytic infiltrate were wild-type, indicating that these mutations are somatic. To demonstrate that these findings are specific, 10 samples of lichen planus were analysed without evidence for FGFR3, PIK3CA or RAS mutations. Conclusions Our results indicate that FGFR3, PIK3CA and RAS mutations are present in approximately 50% of BLKs. These findings support the concept on the molecular genetic level that at least a proportion of BLKs represents regressive variants resulting from former benign epidermal tumours such as seborrhoeic keratosis and solar lentigo.