Reversed better-than-average effect in direct comparisons of nonsocial stimuli depends on the set size

Studies on direct comparative judgments typically show that, for items that are positively evaluated, a single item randomly drawn from a larger set of similar items tends to be judged as better than average (the BTA effect). However, Windschitl, Conybeare, and Krizan (2008) demonstrated that, under timing conditions that do not favor focusing attention on the single item, the reversal of the BTA effect occurs. We report two experiments showing that the magnitude of the reversed BTA effect increases as a function of the size of a multiitem referent with which a single item target is compared. Specifically, in direct comparative judgments of the attractiveness of positively evaluated objects (nice-looking cloth buttons, attractive buildings, or cupcakes), underestimation of the attractiveness of singletons, as compared with a multiitem set (reversed BTA effect), increased with the increased set size. Analysis of absolute judgments obtained for singletons and for small and large multiitem sets suggests that, for attractive stimuli, both the reversed BTA effect in comparative judgments and its sensitivity to set size occur as a result of a positive relationship between set size and perceived attractiveness in absolute judgments

Subunit composition, assembly and regulation of human TIP48 and TIP49 complexes

The two closely related eukaryotic AAA+ proteins, TIP48 and TIP49, are essential components of large multi-protein complexes that are involved in diverse cellular processes. Specific mechanisms for their activity in transcriptional regulation, chromatin remodelling, DNA repair and apoptosis have not yet been characterised; however, different oligomeric forms, sub-cellular localisation and post translational modification of TIP48 and TIP49 may be important in co-ordinating these functions. The assembly of the human TIP48 and TIP49 into different oligomers was studied. Both proteins were mainly monomeric in the absence of nucleotide cofactors. Incubation with ATP or ADP in the presence of Mg2+ modified the distribution of TIP48 oligomers to favour hexamers, but this did not occur with TIP49. The double hexameric complex of TIP48/TIP49 was also analysed and indicated a heterodisperse population of species, which provided clues about assembly pathways. TIP48 and TIP49 are structurally homologous to the bacterial branch migration motor RuvB. TIP48 and TIP49 do not incorporate the DNA binding domain present in RuvB, and instead have acquired a novel domain (Domain II) inserted between the Walker A and B ATPase motifs. Using mutants, we demonstrated that TIP48 Domain II is critical for regulating nucleotide dependent hexamerisation of TIP48. Furthermore, TIP48/TIP49 complexes lacking Domain II indicated that hexamer-hexamer interactions are not exclusively mediated by Domain II; this domain may regulate the assembly of different forms of the heteromeric complex. Interactions between TIP48 and TIP49 and several putative binding partners were tested in vitro. The ATPase activity and oligomerisation of TIP48 and TIP49 were assayed in the presence of Hint1, which was reported to disrupt the homotypic and heterotypic interactions within the TIP48/TIP49 complex. Finally, the sub-cellular localisation and post translational modification of TIP48 and TIP49 were analysed. Using immunofluorescence and GFP-tagged TIP49, we confirmed that TIP48 and TIP49 associate with the mitotic spindle; however, TIP48 accumulates at the midbody during cytokinesis, while TIP49 does not. Furthermore, we investigated potential modifications of TIP48 and TIP49 by 2-D polyacrylamide gel electrophoresis, which may account for the regulation of these distinct functions

Phenotypic Effects of Leptin in an Ectotherm: A New Tool to Study the Evolution of Life Histories and Endothermy?

Leptin is a hormone that regulates energy expenditure and body mass in mammals, and it has attracted considerable attention because of its potential in treating human obesity. Comprehensive data from both pathological and non-pathological systems strongly support a role for leptin in regulating energy metabolism, in thermoregulation and in regulating the onset of puberty. We report here that daily injections of recombinant murine leptin in fence lizards (Sceloporus undulatus) produce phenotypic effects similar to those observed when leptin injections are given to mice, Lizards injected with leptin had body temperatures 0.6 degrees C higher, ate 30 % less food and showed a 14 % reduction in activity rates, and females showed a 2.5-fold increase in resting metabolic rates, compared with lizards injected with vehicle only (phosphate-buffered saline). We also detected native lizard leptin using an immunoassay, Our results indicate that leptin is expressed in ectotherms and may be conserved both functionally and structurally. In the wake of unprecedented research activity on the role of leptin as a cause of, and potential treatment for, human obesity, we believe that other applications of leptin research have been ignored, For example, the response of lizards to leptin injection in our study has important implications for two broad areas of research in evolutionary biology: the evolution of age at first reproduction and of endothermy, We argue that research in these areas, previously limited to comparative approaches, may now benefit from experimental manipulations using leptin

Energy Budgets, Growth Rates, and the rmal Constraints: toward an Integrative Approach to the Study of Life-History Variation

Variation in thermal constraints on activity has been hypothesized to be an important ecological source of geographic variation in growth rates of juvenile eastern fence lizards Sceloporus undulatus. However, most of the evidence to support this hypothesis is either inferential or indirect. In this study, I quantitatively compared thermal constraints on activity and their relationship to growth rates of free-ranging juvenile fence lizards from two extremes of the range of variation in growth rate (Nebraska and New Jersey) used in a reciprocal transplant experiment. I also examined energy allocation made to growth and storage by yearling lizards. Reduced growth rates in New Jersey of normally fast-growing hatchlings from Nebraska were associated with a more stringent thermal constraint on activity corresponding to a 2-3-h shorter predicted daily activity period in New Jersey compared to Nebraska. The thermal constraint on activity was particularly strong (24% less time available in New Jersey compared to Nebraska) during the period when hatchling lizards emerge (August-October). An 8% reduction in total activity lime available over the course of a single year was associated with a 7% reduction in the total amount of energy accumulated by lizards in New Jersey. Differences in the total amount of energy available for allocation were also accompanied by differences in how energy was allocated. Lizards from New Jersey had an allocatable energy pool of approximately 40.34 kJ (88% to growth, 12% to storage, and 0% to reproduction). Lizards from Nebraska had an allocatable pool of 43.44 kJ (22% to growth, 18% to storage, and 60% to reproduction). This study joins others in advocating and illustrating an integrative approach to determining the causes and consequences of life-history variation by combining experimental, comparative, and phylogenetic methods in a single system

Selected Factors Determining the Adaptability of the Gdańsk School Under Sails Participants and Their Temperamental Correlates

Research objectives and problems: The purpose of the study was to test the impact of a high seas cruise on a traditional sailing ship, during which sail training is implemented, on selected characteristics of the participants. It was thought that significant, positive changes would emerge in terms of decision-making, perception of the future, resistance to change, and proactivity – and that these changes would be related to temperament. Research methods: Using the General Decision Making Style instrument, the Consideration of Future Consequences Scale, the Resistance to Change Scale, and the Proactivity Scale, a questionnaire with repeated measurement was administered to two groups of adolescents taking part in a sea cruise (Group 1: 14-day cruise, 11 boys, 8 girls, M age=17.1; Group 2: 7-day cruise, 13 boys, 7 girls, M age = 21.9). Measurements were taken on the first and last day of the cruise and one month after the cruise. Multilevel modeling was used to examine how temperament moderates changes in decision-making style, consideration of future consequences, resistance to change, and level of proactivity. Structure of the article: The text provides information on sail training, including the historical context, previous research, and impact on youths’ development. The role of temperament in shaping behavior and its relevance to sail training are introduced. The theoretical constructs investigated, and the tools used in the research are described. The research objectives are stated and the sample and procedure are explained. The results are presented and discussed. Limitations and conclusions are indicated. Research findings and their impact: Emotional reactivity significantly moderated the increase in dependent and avoidant decision-making styles and short-term focus, while it decreased cognitive rigidity and proactivity. Activity counteracted growth in avoidant decision-making style, reduced resistance to change, routine seeking, and emotional reactivity to change, lowered short-term focus, and supported growth in proactivity. Resilience counteracted the positive development of proactivity. Conclusions and recommendations: Temperament traits can be mediators of change in terms of the constructs discussed herein. The results allow us to look at sail training from a new perspective, though further research on a regular School Under Sails and aboard other sailing ships is needed to formulate indisputable conclusions

Immunohistochemical localization of fibronectin as a tool for the age determination of human skin wounds

We analyzed the distribution of fibronectin in routinely embedded tissue specimens from 53 skin wounds and 6 postmortem wounds. In postmortem wounds a faint but focal positive staining was exclusively found at the margin of the specimens which dit not extend into the adjacent stroma. Vital wounds were classified into 3 groups. The first comprising lesions with wound ages ranging from a few seconds to 30 min, the second comprising those with wound ages upt to 3 weeks, and the third group with lesions more than 3 weeks old. Ten out of 17 lesions with a wound age up to 30 min showed a clear positive reaction within the wound area. Three specimens in this group were completely negative, while in 4 additional cases the result was not significantly different from postmortem lesions. These 7 cases were characterized by acute death with extremely short survival times (only seconds). In wounds up to 3 weeks old fibronectin formed a distinct network containing an increasing number of inflammatory cells corresponding to the wound age. In 2 cases with a survival time of 17 days and in all wounds older than 3 weeks fibronectin was restricted to the surface of fibroblasts and to parallel arranged fibers in the granulation tissue without any network structures. We present evidence that fibronectin is a useful marker for vital wounds with a survival time of more than a few minutes. Fibronectin appears before neutrophilic granulocytes migrate into the wound area. Since a faint positive fibronectin staining is seen in postmortem lesions and bleedings, we propose that only those wounds which show strong positive fibronectin staining also extending into the adjacent stroma should be regarded as vital

Responses of Mole Salamanders to Clearcutting: Using Field Experiments in Forest Management

Impacts of forest management practices on amphibian populations have received growing attention in the last 10 yr. However, to date, measured responses include only comparisons of species diversity indices and population counts without true spatial and temporal controls. We used an experimental approach to test for differences in growth rate, fecundity, age at maturity, and whole-body storage lipids in individual mole salamanders, Ambystoma talpoideum, placed in differently managed habitats. Four 100-m(2) field enclosures were built in each of two habitats, a 4-mo-old clearcut and an adjacent 40-yr-old pine forest. On 19 July 1994, 80 recently metamorphosed and individually marked, weighed, and measured (snout-vent length) A. talpoideum were randomly assigned to field enclosures (n = 640 salamanders). Between 31 October 1994 and 31 March 1995, salamanders were collected from the enclosures using pitfall traps. Body mass and length, whole-body nonpolar storage lipids, clutch size, and egg nonpolar lipids were determined for sexually mature salamanders. After an average of 5-6 mo exposure to clearcut and 40-yr-old pine forest, there were no significant differences between habitats for number of recaptured salamanders, final body mass, final body length, percent whole-body storage lipid, clutch size, or percent storage lipid of eggs. Our results suggest, in contrast to expectations based on many comparative studies with other species, that habitat modification resulting from clearcutting may not have detrimental effects on newly metamorphosed A. talpoideum. We contrast our experimental approach, with its strengths and weaknesses, to previous comparative studies and identify the inherent complexities involved in establishing a causal link between habitat management (clearcutting) and effects on amphibians

Analysis of the distribution of word sentences for the purpose of detecting verbs

This paper presents analysis of the results of detection of verbs deduced by a text-mining mechanism based on the model of the characteristics of words in sentences, based on a relational database structure. Attempt is made to build a mechanism to detect the words based on their statistical distribution in sentences. In article where analyzed Polish and German feuilletons of the various fields of life, in a representative number of 50 Polish articles and 50 German articles.Artykuł przedstawia analizę wyników próby detekcji czasowników wyprowadzonych przez mechanizm typu text mining, oparty o model cech wyrazów w zdaniach, bazujący na strukturze relacyjnej bazy danych. Podjęta została próba stworzenia mechanizmu wykrywającego czasowniki w oparciu o ich rozmieszczenie statystyczne w zdaniach. W artykule przeanalizowane zostały dokumenty tekstowe polskie i niemieckie, będące felietonami o tematyce z różnych dziedzin życia, w reprezentatywnej liczbie 50 artykułów polskich i 50 artykułów niemieckich

The role of thermal niche selection in maintenance of a colour polymorphism in redback salamanders (Plethodon cinereus)

BACKGROUND: In eastern North America two common colour morphs exist in most populations of redback salamanders (Plethodon cinereus). Previous studies have indicated that the different morphs may be adapted to different thermal niches and the morphological variation has been linked to standard metabolic rate at 15°C in one population of P. cinereus. It has therefore been hypothesized that a correlated response to selection on metabolic rate across thermal niches maintains the colour polymorphism in P. cinereus. This study tests that hypothesis. RESULTS: We found that the two colour morphs do sometimes differ in their maintenance metabolic rate (MMR) profiles, but that the pattern is not consistent across populations or seasons. We also found that when MMR profiles differ between morphs those differences do not indicate that distinct niches exist. Field censuses showed that the two colour morphs are sometimes found at different substrate temperatures and that this difference is also dependent on census location and season. CONCLUSION: While these morphs sometimes differ in their maintenance energy expenditures, the differences in MMR profile in this study are not consistent with maintenance of the polymorphism via a simple correlated response to selection across multiple niches. When present, differences in MMR profile do not indicate the existence of multiple thermal niches that consistently mirror colour polymorphism. We suggest that while a relationship between colour morph and thermal niche selection appears to exist it is neither simple nor consistent