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The present ERP study investigated the retrieval of task-irrelevant exemplar-specific information under implicit and explicit memory conditions. Subjects completed either an indirect memory test (a natural/artificial judgment) or a direct recognition memory test. Both test groups were presented with new items, identical repetitions, and perceptually different but conceptually similar exemplars of previously seen study objects. Implicit and explicit memory retrieval elicited clearly dissociable ERP components that were differentially affected by exemplar changes from study to test. In the indirect test, identical repetitions, but not different exemplars, elicited a significant ERP repetition priming effect. In contrast, both types of repeated objects gave rise to a reliable old/new effect in the direct test. The results corroborate that implicit and explicit memory fall back on distinct cognitive representation and, more importantly, indicate that these representations differ in the type of stimulus information stored. Implicit retrieval entailed obligatory access to exemplar-specific perceptual information, despite its being task irrelevant. In contrast, explicit retrieval proved to be more flexible with conceptual and perceptual information accessed according to task demands. [ABSTRACT FROM AUTHOR]

Episodic memory for intrinsic item and extrinsic context information is postulated to rely on two distinct types of representation: object and episodic tokens. These provide the basis for familiarity and recollection, respectively. Electrophysiological indices of these processes (ERP old-new effects) were used together with behavioral data to test these assumptions. We manipulated an intrinsic object feature (color; Experiment 1) and a contextual feature (background; Experiments 1 and 2). In an inclusion task (Experiment 1), the study-test manipulation of color affected object recognition performance and modulated ERP old-new effects associated with both familiarity and recollection. In contrast, a contextual manipulation had no effect, although both intrinsic and extrinsic information was available in a direct feature (source memory) test. When made task relevant (exclusion task; Experiment 2), however, context affected the ERP recollection effect, while still leaving the ERP familiarity effect uninfluenced. We conclude that intrinsic features bound in object tokens are involuntarily processed during object recognition, thus influencing familiarity, whereas context features bound in episodic tokens are voluntarily accessed, exclusively influencing recollection. Figures depicting all the electrodes analyzed are available in an online supplement at www.psychonomic.org/archive. [ABSTRACT FROM AUTHOR]

A series of experiments compared short-term memory for object locations in the auditory and visual modalities. The stimulus materials consisted of sounds and pictures presented at different locations in space. Items were presented in pure- or mixed-modality lists of increasing length. At test, participants responded to renewed presentation of the objects by indicating their original position. If two independent modality-specific and resource-limited short-term memories support the remembering of locations, memory performance should be higher in the mixed-modality than in the pure-modality condition. Yet, memory performance was the same for items in both types of list. In addition, responses to the memory load manipulation in both modalities showed very similar declines in performance. The results are interpreted in terms of objectifies binding object and location information in episodic working memory, independently of the input modality. [ABSTRACT FROM AUTHOR]

If configurations of objects are presented in a S1–S2 matching task for the identity of objects a spatial mismatch effect occurs. Changing the (irrelevant) spatial layout lengthens response times. We investigated what causes this effect. We observed a reliable mismatch effect that was not influenced by a secondary task during maintenance. Neither articulatory suppression (Experiment 1), nor unattended (Experiments 2 and 6) or attended visual material (Experiment 3) reduced the effect, and this was independent of the length of the retention interval (Experiment 6). The effect was also rather independent of the visual appearance of the local elements. It was of similar size with color patches (Experiment 4) and with completely different surface information when testing was cross modal (Experiment 5), and the nameability of the global configuration was not relevant (Experiments 6 and 7). In contrast, the figurative similarity of the configurations of S1 and S2 systematically influenced the size of the spatial mismatch effect (Experiment 7). We conclude that the spatial mismatch effect is caused by a mismatch of the global shape of the configuration stored together with the objects of S1 and not by a mismatch of templates of perceptual records maintained in a visual cache. [ABSTRACT FROM AUTHOR]

Memory for action phrases is better if the actions are enacted in subject-performed tasks (SPTs) than if they are only listened to in verbal tasks (VTs). This effect is ascribed to better item-specific en- coding of SPTs than of VTs. The role of interitem relational information is controversial, and the findings of clustering with categorically structured lists are inconsistent (see Engeilcamp, 1998). The present study contributes to clarifying these effects by demonstrating that intentional relational encoding can be used more efficiently in VTs than in SPTs and influences the degree of clustering, If the list structure is not obvious, inducing intentional encoding by presenting the category labels prior to list presentation and asking subjects to use this preinformation increases clustering in VTs but not in SPTs. Without preinformation, clustering scores of VTs and SPTs did not differ with preinformation, clustering of VTs was stronger than that of SPTs. The authors suggest how the inconsistent findings with regard to clustering effects can be explained. [ABSTRACT FROM AUTHOR]

Enacting action phrases in subject-performed tasks (SPTs) leads to better free recall than hearing or reading the same materials in verbal tasks (VTs). This enactment effect is usually explained by better item-specific information in SPTs than in VTs. The role of relational information is controversial. In the present paper, we will take the multiple recall approach to study the role of item and relational information in memory for actions by computing the number of item gains and the number of item losses over trials. This approach has previously been applied to lists of unrelated action phrases. We applied it to categorically related lists, also allowing a measure of relational information by clustering scores. It was found that SPTs produced more item gains than VTs. This finding confirmed the assumption that SPTs provide better item-specific information than VTs. The number of item losses did not differ between VTs and SPTs. This finding suggests that relational information is equally provided by VTs and SPTs. However, the organizational scores showed a more differentiated picture. Clustering was greater in SPTs than in VTs with randomly presented lists, but not with blocked lists. We suggested that these results, as well as other findings from the literature, could be explained by distinguishing automatic and strategic processes and the types of item associations that are addressed by these processes. [ABSTRACT FROM AUTHOR]

In three experiments, we investigated the influence of the overt performance of signs on memory. Deaf and hearing participants studied lists of action phrases (Experiment 1) or nouns (Experiment 2) under standard verbal instruction, under the instructions to sign the verbal phrase, to symbolically perform the denoted action, or to carry out a prototypical action corresponding to each noun. Higher recall and recognition performances were observed when actions were performed than in the verbal encoding condition, and signing was as effective for memory as was enactment. Thus, overt signing can induce an enactment effect. In contrast, Experiment 3 demonstrated that performing an unrelated action did not. A unique but unrelated action was not memory efficient. [ABSTRACT FROM AUTHOR]

A new approach was taken to study the question whether the free recall advantage of enacting actions (SPT), over only listening to their verbal descriptions (VT), is due to better relational encoding of SPTs than of VTs. The approach consisted of studying related lists and manipulating the degree of relational encoding by repeated list presentation in Experiment 1 and by presenting the list items at random or blocked in Experiment 2. In both experiments, free recall and adjusted ratio of clustering (ARC) scores increased as to be expected with repeated list presentation and blocking. However, these effects proved to be independent of the type of encoding. There was a clear SPT effect in free recall, but in contrast a slight though nonsignificant advantage of VTs over SPTs in ARC scores. Altogether, the experiments show that the SPT effect in free recall is not due to better relational encoding in SPTs than in VTs, in line with the assumption that this effect is due to good item-specific encoding. [ABSTRACT FROM AUTHOR]

We present recent observations of the plasma parameters in coronal holes at the origin of the fast solar wind and in the interplanetary medium. A model based on the heat conductivity law in a dilute plasma shows the coherency of the electron and proton temperature observations from coronal holes to the interplanetary medium. These new observations are severe constraints for any model of the expansion of the fast solar wind. We discuss why and how non-equilibrium multispecies Fokker-Planck approach must be developed and present a generalized Grad's solution. [ABSTRACT FROM AUTHOR]

Educational offerings that utilize environmental and agricultural themes can reinforce basic education for students in kindergarten through twelfth grade (K-12) while also teaching about the environment and agricultural methods and products. A curriculum guide about the environment and food and fiber production was created for K-12 teachers. These materials were evaluated for their effectiveness in increasing student knowledge using elementary classes in several states. It was noted through pre/post tests that younger students, in general, made greater gains. Within five thematic areas, the greatest overall improvement was shown in themes related to the environment. Environmental topics covered, all in the context of agricultural themes, included the need to preserve shared natural resources including land, water, and air as well as the managing of the ecosystem and the use of non-renewable energy resources. Clearly such classroom guides have utility in teaching young students about environmental issues and their relationship to other important topics. This guide and its corresponding Website enhance both opportunities to transmit new knowledge as well as assess performance and impact on behavior. [ABSTRACT FROM AUTHOR]

Focuses on the process by which archaea and some bacteria synthesize Asn-tRNA and Gln-tRNA. Importance of the formation of aminoacyl-transfer RNA to the accuracy of protein synthesis; Details of a study which found that all archaea possess a heterodimeric amidotransferase for Gln-tRNA formation; Differing processes for Asn-tRNA synthesis in archaea.

Investigates the size of the levels-of-processing effects in subject-performed tasks compared to those in standard verbal learning tasks. Interaction between the congruity and the type of encoding with a conceptual orienting task; Low accessibility of items in nonconceptual tasks.

Abstract In a delayed matching task, the influence of spatial congruence between study and test on visual short-term memory for geometric figures and words was investigated. Subjects processed series of pictures which showed three words or three geometric figures arranged as rows or as triangular configurations. At test, the elements were presented in the identical or in the alternative configuration as at study. In the non-matching case, one of the studied elements was exchanged. The delay was 5 s. Subjects judged whether the elements were the same as during study, independent of their configuration. In Exp. l, pictures of figures and words were mixed within one list. For both modalities, the response times were longer if the configuration at test was incongruent to the one at study. This contradicts the results of Santa, who observed effects of spatial congruency for figures, but not for words. In Exp. 2 we therefore presented the same material as in Exp. 1, but now the lists were modality-pure, as in the experiment of Santa i.e., words and figures were shown in different lists. This time, spatial incongruency impaired recognition of the figures, but not recognition of the words. These results show that in a non-verbal context, isolated visually presented words are spatially encoded as nonverbal stimuli (figures) are. However, the word stimuli are encoded differently if the task is a pure verbal one. In the latter case, spatial information is discarded. [ABSTRACT FROM AUTHOR]

Presents two analyses of recognition performance. Enhancement of recognition through actions; Effects to memory of actions enacted prior to recognition to recognition; Bizarreness effect in verbal coding task; Reduction of the effect of enactment to recognition.

The Spatio-Temporal Analysis of Field Fluctuations (STAFF) experiment is one of five experiments which together comprise the Wave Experiment Consortium (WEC). STAFF consists of a three-axis search coil magnetometer to measure magnetic fluctuations at frequencies up to 4 kHz, and a spectrum analyser to calculate in near-real time aboard the spacecraft, the complete auto- and cross-spectral matrices using the three magnetic and two electric components of the electromagnetic field. The magnetic waveform at frequencies below either 10 Hz or 180 Hz is also transmitted. The sensitivity of the search coil is adapted to the phenomena theo be studied: the values 3 × 10-3 nT Hz-1/2 and 3 × 10-5 nT Hz-1/2 are achieved respectively at 1 Hz and 100 Hz. The dynamic range of the STAFF instruments is about 96 dB in both waveform and spectral power, so as to allow the study of waves near plasma boundaries. Scientific objectives of the STAFF investigations, particularly those requiring four point measurements, are discussed. Methods by which the wave data will be characterised are described with emphasis on those specific to four-point measurements, including the use of the Field Energy Distribution function. [ABSTRACT FROM AUTHOR]

A Boltzmann H-functional is derived in the so called physical representation introduced by Prigogine et al. It is proved that at equilibrium it contains the potential contributions to the specific entropy of the moderately dense gas. We shall discuss its validity in the linear domain of irreversible processes. [ABSTRACT FROM AUTHOR]

The article describes the use of spliced mixed lineage leukemia (MLL) fusions to generate functional chimeric MLL-MLLT1 transcripts in 40 acute leukemia patients carrying the t(11;19)(q23; 13.3) chromosomal translocation. Transcriptional read-through and subsequent splicing to other transcription units is a novel property of disrupted MLL genes in order to create functional MLL fusions.

OBJECTIVE:: To determine the prevalence and clinical features of malnutrition and its relationship with the CFTR genotype in a cystic fibrosis (CF) adult population. DESIGN:: Cross-sectional study. SETTING:: Department of Pulmonology, Cochin Hospital, Paris, France. SUBJECTS:: 163 CF adults seen between 1997 and 1999. RESULTS:: Mean age was 28.8?y. Mean body mass index (BMI) was 19.1?kg/m2. Malnutrition (BMI<18.5?kg/m2) was seen in 81 patients (49.7%). Its severity was associated with diagnosis of CF before the age of 18?y (P<0.01), FEV1 values below 30%(P<0.01), the yearly decline of FEV1 (P<0.01), pancreatic insufficiency (P<0.01) and gastro-oesophageal reflux (P<0.01). Malnutrition was observed in 58.7%of patients with a severe CFTR genotype but in 28.6%of patients with a mild genotype (P<0.001). CONCLUSION:: Malnutrition remains frequent in adults with CF except in patients presenting with a mild CFTR genotype (leading to a mild phenotype and to later diagnosis). SPONSORSHIP:: None.European Journal of Clinical Nutrition (2005) 59, 152-154. doi:10.1038/sj.ejcn.1602039 Published online 15 September 2004 [ABSTRACT FROM AUTHOR]

Through exomic sequencing of ten hepatitis C virus (HCV)-associated hepatocellular carcinomas (HCC) and subsequent evaluation of additional affected individuals, we discovered novel inactivating mutations of ARID2 in four major subtypes of HCC (HCV-associated HCC, hepatitis B virus (HBV)-associated HCC, alcohol-associated HCC and HCC with no known etiology). Notably, 18.2% of individuals with HCV-associated HCC in the United States and Europe harbored ARID2 inactivation mutations, suggesting that ARID2 is a tumor suppressor gene that is relatively commonly mutated in this tumor subtype. [ABSTRACT FROM AUTHOR]