A Benefit of Context Reinstatement to Recognition Memory in Aging: The Role of Familiarity Processes

Reinstatement of encoding context facilitates memory for targets in young and older individuals (e.g., a word studied on a particular background scene is more likely to be remembered later if it is presented on the same rather than a different scene or no scene), yet older adults are typically inferior at recalling and recognizing target–context pairings. This study examined the mechanisms of the context effect in normal aging. Age differences in word recognition by context condition (original, switched, none, new), and the ability to explicitly remember target–context pairings were investigated using word–scene pairs (Experiment 1) and word–word pairs (Experiment 2). Both age groups benefited from context reinstatement in item recognition, although older adults were significantly worse than young adults at identifying original pairings and at discriminating between original and switched pairings. In Experiment 3, participants were given a three-alternative forced-choice recognition task that allowed older individuals to draw upon intact familiarity processes in selecting original pairings. Performance was age equivalent. Findings suggest that heightened familiarity associated with context reinstatement is useful for boosting recognition memory in aging

A benefit of context reinstatement to recognition memory in aging: the role of familiarity processes

Reinstatement of encoding context facilitates memory for targets in young and older individuals (e.g., a word studied on a particular background scene is more likely to be remembered later if it is presented on the same rather than a different scene or no scene), yet older adults are typically inferior at recalling and recognizing target–context pairings. This study examined the mechanisms of the context effect in normal aging. Age differences in word recognition by context condition (original, switched, none, new), and the ability to explicitly remember target–context pairings were investigated using word–scene pairs (Experiment 1) and word–word pairs (Experiment 2). Both age groups benefited from context reinstatement in item recognition, although older adults were significantly worse than young adults at identifying original pairings and at discriminating between original and switched pairings. In Experiment 3, participants were given a three-alternative forced-choice recognition task that allowed older individuals to draw upon intact familiarity processes in selecting original pairings. Performance was age equivalent. Findings suggest that heightened familiarity associated with context reinstatement is useful for boosting recognition memory in aging

Mass Measurement Using Energy Spectra in Three-body Decays

In previous works we have demonstrated how the energy distribution of massless decay products in two body decays can be used to measure the mass of decaying particles. In this work we show how such results can be generalized to the case of multi-body decays. The key ideas that allow us to deal with multi-body final states are an extension of our previous results to the case of massive decay products and the factorization of the multi-body phase space. The mass measurement strategy that we propose is distinct from alternative methods because it does not require an accurate reconstruction of the entire event, as it does not involve, for instance, the missing transverse momentum, but rather requires measuring only the visible decay products of the decay of interest. To demonstrate the general strategy, we study a supersymmetric model wherein pair-produced gluinos each decay to a stable neutralino and a bottom quark-antiquark pair via an off-shell bottom squark. The combinatorial background stemming from the indistinguishable visible final states on both decay sides can be treated by an "event mixing" technique, the performance of which is discussed in detail. Taking into account dominant backgrounds, we are able to show that the mass of the gluino and, in favorable cases, that of the neutralino can be determined by this mass measurement strategy.Comment: 42 pages, 12 figures, Journal-submitted versio

Specific and non specific hybridization of oligonucleotide probes on microarrays

Gene expression analysis by means of microarrays is based on the sequence specific binding of mRNA to DNA oligonucleotide probes and its measurement using fluorescent labels. The binding of RNA fragments involving other sequences than the intended target is problematic because it adds a "chemical background" to the signal, which is not related to the expression degree of the target gene. The paper presents a molecular signature of specific and non specific hybridization with potential consequences for gene expression analysis. We analyzed the signal intensities of perfect match (PM) and mismatch (MM) probes of GeneChip microarrays to specify the effect of specific and non specific hybridization. We found that these events give rise to different relations between the PM and MM intensities as function of the middle base of the PMs, namely a triplet- (C>G=T>A>0) and a duplet-like (C=T>0>G=A) pattern of the PM-MM log-intensity difference upon binding of specific and non specific RNA fragments, respectively. The systematic behaviour of the intensity difference can be rationalized on the level of base pairings of DNA/RNA oligonucleotide duplexes in the middle of the probe sequence. Non-specific binding is characterized by the reversal of the central Watson Crick (WC) pairing for each PM/MM probe pair, whereas specific binding refers to the combination of a WC and a self complementary (SC) pairing in PM and MM probes, respectively. The intensity of complementary MM introduces a systematic source of variation which decreases the precision of expression measures based on the MM intensities

The effect of paired comparisons on triple choice sets : a thesis presented in partial fulfilment of the requirements for the degree of Master of Business Studies in Marketing at Massey University, Palmerston North, New Zealand

As consumers become aware of different brands they might purchase, it is likely they will consider those brands by making a series of paired comparisons, before finally settling on one option they prefer most. Choice theory suggests that preferences are formed early, so by influencing a consumer to prefer one option in favour of other options at the start of a choice episode, this can have a systematic effect on subsequent, and in particular final choice. Simonson, Nowlis, and Lemon (1993) assert that consumers who make paired comparisons of alternatives that vary in price and quality before selecting from a triple set of the same options are more likely to choose the cheapest option, than those who evaluate just the triple set comprised of the same options. Four experiments tested this claim but the predicted effect failed to occur. Moreover, results from one experiment had the reverse effect, the preference share of the cheapest option decreased, while the share of the more expensive options increased. This was a statistically significant result. This contra finding is in agreement with the large body of published evidence that suggests consumers, when it is possible for them to do so, prefer higher quality to lower quality options. The effect of background factors on choice was of concern, so the effect of gender, household income, and age on choice was tested. Results from these tests were inconsistent, and showed that only young males from high-income households were significantly effected by the stepwise treatment. There was concern that heterogeneity in the sampled group of respondents might have confounded the measurement of treatment effects. To help reduce the influence of background factors, all results were weighted. However, Simonson et al. did not account for heterogeneity, so it is possible their treatments have interacted with some background factor associated with the context of choice, individual difference between respondents, or the product attributes. For this reason, the claim by Simonson et al. is open to criticism. Alternative explanations for Simonson et al. (1993) findings are advanced. New research is required into the effects of paired comparisons on choice

Faster computation of the Tate pairing

This paper proposes new explicit formulas for the doubling and addition step in Miller's algorithm to compute the Tate pairing. For Edwards curves the formulas come from a new way of seeing the arithmetic. We state the first geometric interpretation of the group law on Edwards curves by presenting the functions which arise in the addition and doubling. Computing the coefficients of the functions and the sum or double of the points is faster than with all previously proposed formulas for pairings on Edwards curves. They are even competitive with all published formulas for pairing computation on Weierstrass curves. We also speed up pairing computation on Weierstrass curves in Jacobian coordinates. Finally, we present several examples of pairing-friendly Edwards curves.Comment: 15 pages, 2 figures. Final version accepted for publication in Journal of Number Theor