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Humans assess the credibility of information gained from others on a daily basis; this ongoing assessment is especially crucial for avoiding exploitation by others. We used a repeated, two-person bargaining game and a cognitive hierarchy model to test how subjects judge the information sent asymmetrically from one player to the other. The weight that they give to this information is the result of two distinct factors: their baseline suspicion given the situation and the suspicion generated by the other person's behavior. We hypothesized that human brains maintain an ongoing estimate of the credibility of the other player and sought to uncover neural correlates of this process. In the game, sellers were forced to infer the value of an object based on signals sent from a prospective buyer. We found that amygdala activity correlated with baseline suspicion, whereas activations in bilateral parahippocampus correlated with trial-by-trial uncertainty induced by the buyer's sequence of suggestions. In addition, the less credible buyers that appeared, the more sensitive parahippocampal activation was to trial-by-trial uncertainty. Although both of these neural structures have previously been implicated in trustworthiness judgments, these results suggest that they have distinct and separable roles that correspond to their theorized roles in learning and memory. [ABSTRACT FROM AUTHOR]

Recently, there has been significant interest in developing underwater vehicles inspired by jellyfish. One of these notable efforts includes the artificial Aurelia aurita (Robojelly). The artificial A. aurita is able to swim with similar proficiency to the A. aurita species of jellyfish even though its deformation profile does not completely match the natural animal. In order to overcome this problem, we provide a systematic finite element model (FEM) to simulate the transient behavior of the artificial A. aurita vehicle utilizing bio-inspired shape memory alloy composite (BISMAC) actuators. The finite element simulation model accurately captures the hyperelastic behavior of EcoFlex (Shore hardness-0010) room temperature vulcanizing silicone by invoking a three-parameter Mooney-Rivlin model. Furthermore, the FEM incorporates experimental temperature transformation curves of shape memory alloy wires by introducing negative thermal coefficient of expansion and considers the effect of gravity and fluid buoyancy forces to accurately predict the transient deformation of the vehicle. The actual power cycle used to drive artificial A. aurita vehicle was used in the model. The overall profile error between FEM and the vehicle profile is mainly due to the difference in initial relaxed profiles. [ABSTRACT FROM AUTHOR]

The management and manipulation of our own social image in the minds of others requires difficult and poorly understood computations. One computation useful in social image management is strategic deception: our ability and willingness to manipulate other people's beliefs about ourselves for gain. We used an interpersonal bargaining game to probe the capacity of players to manage their partner's beliefs about them. This probe parsed the group of subjects into three behavioral types according to their revealed level of strategic deception; these types were also distinguished by neural data measured during the game. The most deceptive subjects emitted behavioral signals that mimicked a more benign behavioral type, and their brains showed differential activation in right dorsolateral prefrontal cortex and left Brodmann area 10 at the time of this deception. In addition, strategic types showed a significant correlation between activation in the right temporoparietal junction and expected payoff that was absent in the other groups. The neurobehavioral types identified by the game raise the possibility of identifying quantitative biomarkers for the capacity to manipu- late and maintain a social image in another person's mind. [ABSTRACT FROM AUTHOR]

Research on emotion regulation has focused upon observers' ability to regulate their emotional reaction to stimuli such as affective pictures, but many other aspects of our affective experience are also potentially amenable to intentional cognitive regulation. In the domain of decision-making, recent work has demonstrated a role for emotions in choice, although such work has generally remained agnostic about the specific role of emotion. Combining psychologically-derived cognitive strategies, physiological measurements of arousal, and an economic model of behavior, this study examined changes in choices (specifically, loss aversion) and physiological correlates of behavior as the result of an intentional cognitive regulation strategy. Participants were on average more aroused per dollar to losses relative to gains, as measured with skin conductance response, and the difference in arousal to losses versus gains correlated with behavioral loss aversion across subjects. These results suggest a specific role for arousal responses in loss aversion. Most importantly, the intentional cognitive regulation strategy, which emphasized "perspective-taking," uniquely reduced both behavioral loss aversion and arousal to losses relative to gains, largely by influencing arousal to losses. Our results confirm previous research demonstrating loss aversion while providing new evidence characterizing individual differences and arousal correlates and illustrating the effectiveness of intentional regulation strategies in reducing loss aversion both behaviorally and physiologically. [ABSTRACT FROM AUTHOR]

The article examines the safety and efficacy of a two-week period of therapy with inhaled mannitol for patients with cystic fibrosis (CF). Research findings show that lung function in CF patients was significantly improved by the inhaled mannitol treatment, which was also found to be well tolerated and safe for patients.

In this paper, a reduced-complexity soft-interference- cancellation minimum mean-square-error (SIC-MMSE) iterative equalization method for severe time-dispersive multiple-input-multiple-output (MIMO) channels is proposed. To mitigate the severe time dispersiveness of the channel, a single carrier with cyclic prefix is employed, and the equalization is performed in the frequency domain. This simplifies the challenging problem of equalization in MIMO channels due to both the intersymbol interference (ISI) and the coantenna interference (CAl). The proposed iterative algorithm works in two stages. The first stage estimates the transmitted frequency-domain symbols using a low-complexity SIC-MMSE equalizer. The second stage converts the estimated frequency- domain symbols in the time domain and finds their means and variances to incorporate in the SIC-MMSE equalizer in the next iteration. Simulation results show the bit-/symbol-error-rate performance of the SIC-MMSE equalizer, with and without coding, for various modulation schemes. [ABSTRACT FROM AUTHOR]

Reinforcement learning models now provide principled guides for a wide range of reward learning experiments in animals and humans. One key learning (error) signal in these models is experiential and reports ongoing temporal differences between expected and experienced reward. However, these same abstract learning models also accommodate the existence of another class of learning signal that takes the form of a fictive error encoding ongoing differences between experienced returns and returns that ‘could-have-been-experienced’ if decisions had been different. These observations suggest the hypothesis that, for all real-world learning tasks, one should expect the presence of both experiential and fictive learning signals. Motivated by this possibility, we used a sequential investment game and fMRI to probe ongoing brain responses to both experiential and fictive learning signals generated throughout the game. Using a large cohort of subjects (n = 54), we report that fictive learning signals strongly predict changes in subjects' investment behavior and correlate with fMRI signals measured in dopaminoceptive structures known to be involved in valuation and choice. [ABSTRACT FROM AUTHOR]

The article focuses on the study that describes the impact of texturized vegetable protein (TVP) containing indigestible soy carbohydrate to blood insulin concentrations in dogs fed high fat diets. Methods of the study include examining the influence of high amounts of TVP on blood glucose and insulin properties following a meal for 6-12 hours after high-fat canned diets were fed to dogs. Results taken reveal that high fat complex diets fed to dogs influence blood glucose concentrations which decrease the effect of assessment of TVP on the hormonal response. On the other hand, soy carbohydrate may set an advantage to the regulation of hyperglycemia in dogs with diabetes.

Searching for the optimum tap-length that best balances the complexity and steady-state performance of an adaptive filter has attracted attention recently. Among existing algorithms that can be found in the literature, two of which, namely the segmented filter (SF) and gradient descent (GD) algorithms, are of particular interest as they can search for the optimum tap-length quickly. In this paper, at first, we carefully compare the SF and GD algorithms and show that the two algorithms are equivalent in performance under some constraints, but each has advantages/dis-advanges relative to the other. Then, we propose an improved vari- able tap-length algorithm using the concept of the pseudo fractional tap-length (FT). Updating the tap-length with instantaneous errors in a style similar to that used in the stochastic gradient [or least mean squares (LMS)] algorithm, the proposed FT algorithm not only retains the advantages from both the SF and the GD algorithms but also has significantly less complexity than existing algorithms. Both performance analysis and numerical simulations are given to verify the new proposed algorithm. [ABSTRACT FROM AUTHOR]

High-speed field-programmable gate array (FPGA) implementations of an adaptive least mean square (LMS) filter with application in an electronic support measures (ESM) digital receiver, are presented. They employ ‘fine-grained’ pipelining, i.e., pipelining within the processor and result in an increased output latency when used in the LMS recursive system. Therefore, the major challenge is to maintain a low latency output whilst increasing the pipeline stage in the filter for higher speeds. Using the delayed LMS (DLMS) algorithm, fine-grained pipelined FPGA implementations using both the direct form (DF) and the transposed form (TF) are considered and compared. It is shown that the direct form LMS filter utilizes the FPGA resources more efficiently thereby allowing a 120 MHz sampling rate. [ABSTRACT FROM AUTHOR]

This paper presents coefficient filtering techniques in the least mean squares (LMS) algorithm to improve adaptive predictor tracking performance for time-varying chirped signals. The example application used in this paper is an electronic support measure (ESM) receiver for detecting radar chirped pulses. The leakage LMS, momentum LMS, and the proposed future-state coefficient (FC-LMS) filtering algorithms have been studied. The leakage LMS algorithm has the ability to remove the memory effect of the initial converged time-varying frequency of the chirped signal, thus Improving the radar pulse detection performance. The momentum LMS is able to search for the time-varying optimum weight solution more efficiently, and the FC-LMS uses a parallel technique to retain the LMS throughput while being able, to show a better tracking performance for chirped' signals compared with the standard LMS algorithm. [ABSTRACT FROM AUTHOR]

The detailed analysis of team interactions can be a source of insight into team processes and how teams interact with technology. Video recordings afford an exciting medium for such analysis. We describe a study of team leadership in the highly dynamic, high-stakes environment of trauma resuscitation. The study was conducted through video recording team activities in actual work settings and analysing the video data using a grounded theory approach. The primary research questions were: what are the functions of team leadership and how do they vary according to task situations? A corpus of 152 video segments from 18 trauma patient resuscitation cases was compiled to address these research questions. A catalog of team leadership functions was developed, along with a categorisation of the task situations in which team leadership occurred. The implications of this catalog and the mapping between leadership and task situations are discussed in relation to the findings from an interview study and a survey study on team leadership. The methodological advantages of a grounded theory approach for in-context video analysis for studying work are also discussed. [ABSTRACT FROM AUTHOR]

Five chemically modified heparins were derived from native pig mucosal heparin (pig heparin IH). These were de-N-sulphated heparin (heparin IH), N-acetylheparin (heparin IA), de-N/O-sulphated heparin (heparin lVH), de[O-sulphated heparin (heparin IVs) and de-O-sulphated N-acetyl-heparin (heparin IVA). Their structures were studied by 13C-NMR spectroscopy at 90.56 MHz. Native heparin and the derivatives were incubated with Flavobacterium heparinase II at 25°C. The progress of degradation was followed by the Δ A235 and the final composition examined by gel filtration with Bio-Gel P-4. Native heparin (Is) was readily degraded by heparinase II and, with the exception of heparin IVH for which degradation was negligible, the chemically modified derivatives were also degraded. Approximately 90% of the saccharides from heparins Is, IA, IVs and IVA were disaccharides and tetrasaccharides. For heparin IH, which was degraded more slowly, the proportion was 65%. Heparins Is, IVs and IVA underwent initial rapid degradation. The digestion of heparin IA proceeded rapidly after an initial lag phase. The undegraded polymers produced similar elution profiles from Bio-Gel P-4. Following the action of heparinase II on heparins Is, IA, lVs and IVA, the elution profiles revealed a major peak of disaccharides and minor peaks of higher oligomers. The profile of heparin 1H revealed a greater proportion of intermediate- molecular-mass saccharides. Our results demonstrate a broad specificity for heparinase 11. It is capable of lysing both N-acetylated and N- sulphated heparins independent of O-sulphation. Heparinase II will also degrade heparin derivatives that are non- N-substituted provided that they are O-sulphated. [ABSTRACT FROM AUTHOR]

The capacity of in vitro cultured common wheat (Triticum aestivum L.) endosperms to incorporate starch and protein precursors was investigated, isolated 2-3 week-old endosperms were cultured up to 2 weeks in a liquid medium containing labelled (14C)-sucrose and 3H)-glutamine. Cultured endosperms were separated into ethanolsoluble, starch and protein fractions and the incorporation of the label into each of these fractions was assessed at different times! after commencement of culture. The same medium was introduced through the peduncle into normally-developing grains, which were then similarly analyzed. Accumulation of both 14C and 3H in the ethanol- soluble fraction occurred, at a decreasing rate, only during the first 3 days, and then ceased. The accumulated label in the starch fraction, which originated mainly as sucrose, proceeded at a relatively constant rate for one week and reached only about 1/5 of the expected in vivo starch production. Incorporation of both isotopes into the protein fraction reflected similar utilization of sucrose and glutamine from the medium (molar base), decreasing in rate with time. Culturing beyond one week produced deteriorated endosperms. Compared to cultured endosperms, normally-developing grains incorporated proportionally less precursors into the ethanol-soluble and more into the insoluble fraction. It is suggested that the reduced starch and protein synthesis in cultured grains stems from impaired capacity of the biosynthetic machinery rather than from low availability of precursors. [ABSTRACT FROM AUTHOR]