905 resultados para kidding interval


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This study examined the effect of schemas on consistency and accuracy of memory across interviews, providing theoretical hypotheses explaining why inconsistencies may occur. The design manipulated schema-typicality of items (schema-typical and atypical), question format (free-recall, cued-recall and recognition) and retention interval (immediate/2 week and 2 week/4 week). Consistency, accuracy and experiential quality of memory were measured. ^ All independent variables affected accuracy and experiential quality of memory while question format was the only variable affecting consistency. These results challenge the commonly held notion in the legal arena that consistency is a proxy for accuracy. The study also demonstrates that other variables, such as item-typicality and retention interval have different effects on consistency and accuracy in memory. ^

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The purpose of this study was to determine the extent to which oceanic anoxic events (OAE's) are recorded in deep-water deposits of the former western Tethyan Sea, by investigating the Cenomanian-Turonian time interval characterized by the worldwide OAE 2 event. The study improved our knowledge of the possible controlling mechanisms that triggered this event at these sites, and furthered our understanding of this global phenomenon. This was examined by high-resolution, multi-proxy analyses of sediments at DSDP Sites 386 and 144, including sedimentology, scanning electron microscopy, stable isotopes, bulk and clay mineralogy, major and trace element geochemistry, biomarkers, and paleontological data. ^ The results provide a better stratigraphic resolution for the Cenomanian-Turonian, which allowed for more precise determination of chronologic boundaries, sedimentation rates at DSDP Site 386, and a more accurate calculation of the frequency of the cycles recorded in the sequence, which fall predominantly within the precession (∼23 kyr) and short eccentricity (∼100 kyr) ranges. The combined proxies allow assessment of the correlation of δ13Corg, and major and trace elements with the predominance of cyanobacteria. These organisms were the main producers of the organic matter during the dysoxic and euxinic conditions of OAE 2 at DSDP Site 386. A huge amount of microcrystalline quartz of eolian origin is also associated with OAE 2. The geochemical proxies further provide evidence that OAE 2 was linked to increased volcanism outside the deep water of the proto-Atlantic Ocean. The clays in the Turonian sediments are terrigenous and derived predominantly from eolian transport. Comparing DSDP Site 386 and 144 with stratotype sections, the δ13C org and TOC data indicate that OAE 2 seems diachronous throughout the proto-Atlantic Ocean. ^ This study concludes that the development of anoxic conditions in the deep water of the Atlantic during the latest Cenomanian-Turonian resulted from a combination of factors related to local oceanic setting and mitigated by global tectonism and climate. The data provide a more comprehensive view of the interacting factors that led to sustained high productivity of the cyanobacteria and photosynthetic protists that produced organic-carbon-rich deposits in the world's oceans. ^

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This dissertation presents a unique research opportunity by using recordings which provide electrocardiogram (ECG) plus a reference breathing signal (RBS). ECG derived breathing (EDR) is measured and correlated against RBS. Standard deviations of multiresolution wavelet analysis coefficients (SDMW) are obtained from heart rate and classified using RBS. Prior works by others used select patients for sleep apnea scoring with EDR but no RBS. Another prior work classified select heart disease patients with SDMW but no RBS. This study used randomly chosen sleep disorder patient recordings; central and obstructive apneas, with and without heart disease.^ Implementation required creating an application because existing systems were limited in power and scope. A review survey was created to choose a development environment. The survey is presented as a learning tool and teaching resource. Development objectives were rapid development using limited resources (manpower and money). Open Source resources were used exclusively for implementation. ^ Results show: (1) Three groups of patients exist in the study. Grouping RBS correlations shows a response with either ECG interval or amplitude variation. A third group exists where neither ECG intervals nor amplitude variation correlate with breathing. (2) Previous work done by other groups analyzed SDMW. Similar results were found in this study but some subjects had higher SDMW, attributed to a large number of apneas, arousals and/or disconnects. SDMW does not need RBS to show apneic conditions exist within ECG recordings. (3) Results in this study support the assertion that autonomic nervous system variation was measured with SDMW. Measurements using RBS are not corrupted due to breathing even though respiration overlaps the same frequency band.^ Overall, this work becomes an Open Source resource which can be reused, modified and/or expanded. It might fast track additional research. In the future the system could also be used for public domain data. Prerecorded data exist in similar formats in public databases which could provide additional research opportunities. ^

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Accurate knowledge of the time since death, or postmortem interval (PMI), has enormous legal, criminological, and psychological impact. In this study, an investigation was made to determine whether the relationship between the degradation of the human cardiac structure protein Cardiac Troponin T and PMI could be used as an indicator of time since death, thus providing a rapid, high resolution, sensitive, and automated methodology for the determination of PMI. ^ The use of Cardiac Troponin T (cTnT), a protein found in heart tissue, as a selective marker for cardiac muscle damage has shown great promise in the determination of PMI. An optimized conventional immunoassay method was developed to quantify intact and fragmented cTnT. A small sample of cardiac tissue, which is less affected than other tissues by external factors, was taken, homogenized, extracted with magnetic microparticles, separated by SDS-PAGE, and visualized with Western blot by probing with monoclonal antibody against cTnT. This step was followed by labeling and available scanners. This conventional immunoassay provides a proper detection and quantitation of cTnT protein in cardiac tissue as a complex matrix; however, this method does not provide the analyst with immediate results. Therefore, a competitive separation method using capillary electrophoresis with laser-induced fluorescence (CE-LIF) was developed to study the interaction between human cTnT protein and monoclonal anti-TroponinT antibody. ^ Analysis of the results revealed a linear relationship between the percent of degraded cTnT and the log of the PMI, indicating that intact cTnT could be detected in human heart tissue up to 10 days postmortem at room temperature and beyond two weeks at 4C. The data presented demonstrates that this technique can provide an extended time range during which PMI can be more accurately estimated as compared to currently used methods. The data demonstrates that this technique represents a major advance in time of death determination through a fast and reliable, semi-quantitative measurement of a biochemical marker from an organ protected from outside factors. ^

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The three-parameter lognormal distribution is the extension of the two-parameter lognormal distribution to meet the need of the biological, sociological, and other fields. Numerous research papers have been published for the parameter estimation problems for the lognormal distributions. The inclusion of the location parameter brings in some technical difficulties for the parameter estimation problems, especially for the interval estimation. This paper proposes a method for constructing exact confidence intervals and exact upper confidence limits for the location parameter of the three-parameter lognormal distribution. The point estimation problem is discussed as well. The performance of the point estimator is compared with the maximum likelihood estimator, which is widely used in practice. Simulation result shows that the proposed method is less biased in estimating the location parameter. The large sample size case is discussed in the paper.

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Recent studies have shown the importance of the beat-by-beat changes in heart rate influenced by the autonomic nervous system (ANS), or heart rate variability (HRV). The purpose of this study was to examine the lasting effects of hypoxic exercise on HRV, and its influences on substrate usage. Results from this study could lead an increased understanding on this topic. Eight active healthy males (age: 31±11 years; height: 180±7 cm; weight: 83±8 kg; VO₂max (maximal oxygen consumption): 4.4±0.6 L•min⁻¹) underwent normoxic and hypoxic (FᵢO₂= 0.15) conditions during high-intensity interval (HIIT) cycling (70%-high interval, 35%-rest interval). Cycling intensity was determined by a peak power output cycling test. Each experimental session consisted of a basal metabolic rate determination, up to 45-minutes of HIIT cycling, and three 30-minute post-exercise metabolic rate measurements (spanning 3 hours and 15 minutes after exercise). During exercise, RPE was higher (p<0.01) and LAC (lactate) increased (p=0.001) at each point of time in hypoxia, with no change in normoxia. After hypoxic exercise, the SNS/PNS ratio (overall ANS activity) was significantly higher (p<0.01) and significantly decreased through time in both conditions (p<0.01). In addition, a significant interaction between time and conditions (p<0.02) showed a decrease in LAC concentration through time post-hypoxic exercise. The findings showed that a single bout of hypoxic exercise alters ANS activity post-exercise along with shifting substrate partitioning from glycolytic to lipolytic energy production. The significant decrease in LAC concentration post-hypoxic exercise supports the notion that hypoxic HIIT induces a greater muscle glycogen depletion leading to increased fat oxidation to sustain glycogenesis and gluconeogenesis to maintain blood glucose level during recovery.

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The last glacial millennial climatic events (i.e. Dansgaard-Oeschger and Heinrich events) constitute outstanding case studies of coupled atmosphere-ocean-cryosphere interactions. Here, we investigate the evolution of sea-surface and subsurface conditions, in terms of temperature, salinity and sea ice cover, at very high-resolution (mean resolution between 55 and 155 years depending on proxies) during the 35-41 ka cal BP interval covering three Dansgaard-Oeschger cycles and including Heinrich event 4, in a new unpublished marine record, i.e. the MD99-2285 core (62.69°N; -3.57s°E). We use a large panel of complementary tools, which notably includes dinocyst-derived sea-ice cover duration quantifications. The high temporal resolution and multiproxy approach of this work allows us to identify the sequence of processes and to assess ocean-cryosphere interactions occurring during these periodic ice-sheet collapse events. Our results evidence a paradoxical hydrological scheme where (i) Greenland interstadials are marked by a homogeneous and cold upper water column, with intensive winter sea ice formation and summer sea ice melting, and (ii) Greenland and Heinrich stadials are characterized by a very warm and low saline surface layer with iceberg calving and reduced sea ice formation, separated by a strong halocline from a less warm and saltier subsurface layer. Our work also suggests that this stadial surface/subsurface warming started before massive iceberg release, in relation with warm Atlantic water advection. These findings thus support the theory that upper ocean warming might have triggered European ice-sheet destabilization. Besides, previous paleoceanographic studies conducted along the Atlantic inflow pathways close to the edge of European ice-sheets suggest that such a feature might have occurred in this whole area. Nonetheless, additional high resolution paleoreconstructions are required to confirm such a regional scheme.

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Acknowledgments We thank A. B. Duthie, S. Losdat, and M. E. Wolak for useful discussions and comments and the European Research Council for funding. We also thank the two reviewers, whose suggestions greatly improved the manuscript.

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Acknowledgments We thank A. B. Duthie, S. Losdat, and M. E. Wolak for useful discussions and comments and the European Research Council for funding. We also thank the two reviewers, whose suggestions greatly improved the manuscript.

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The standard difference model of two-alternative forced-choice (2AFC) tasks implies that performance should be the same when the target is presented in the first or the second interval. Empirical data often show “interval bias” in that percentage correct differs significantly when the signal is presented in the first or the second interval. We present an extension of the standard difference model that accounts for interval bias by incorporating an indifference zone around the null value of the decision variable. Analytical predictions are derived which reveal how interval bias may occur when data generated by the guessing model are analyzed as prescribed by the standard difference model. Parameter estimation methods and goodness-of-fit testing approaches for the guessing model are also developed and presented. A simulation study is included whose results show that the parameters of the guessing model can be estimated accurately. Finally, the guessing model is tested empirically in a 2AFC detection procedure in which guesses were explicitly recorded. The results support the guessing model and indicate that interval bias is not observed when guesses are separated out.

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Humans and animals have remarkable capabilities in keeping time and using time as a guide to orient their learning and decision making. Psychophysical models of timing and time perception have been proposed for decades and have received behavioral, anatomical and pharmacological data support. However, despite numerous studies that aimed at delineating the neural underpinnings of interval timing, a complete picture of the neurobiological network of timing in the seconds-to-minutes range remains elusive. Based on classical interval timing protocols and proposing a Timing, Immersive Memory and Emotional Regulation (TIMER) test battery, the author investigates the contributions of the dorsal and ventral hippocampus as well as the dorsolateral and the dorsomedial striatum to interval timing by comparing timing performances in mice after they received cytotoxic lesions in the corresponding brain regions. On the other hand, a timing-based theoretical framework for the emergence of conscious experience that is closely related to the function of the claustrum is proposed so as to serve both biological guidance and the research and evolution of “strong” artificial intelligence. Finally, a new “Double Saturation Model of Interval Timing” that integrates the direct- and indirect- pathways of striatum is proposed to explain the set of empirical findings.

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The sediments within Toolik Lake in arctic Alaska are characterized by extremely low rates of organic matter sedimentation and unusually high concentrations of iron and manganese. Pore water and solid phase measurements of iron, manganese, trace metals, carbon, nitrogen, phosphorus, and sulfur are consistent with the hypothesis that the reduction of organic matter by iron and manganese is the most important biogeochemical reaction within the sediment. Very low rates of dissolved oxygen consumption by the sediments result in an oxidizing environment at the sediment-water interface. This results in high retention of upwardly-diffusing iron and manganese and the formation of metal-enriched sediment. Phosphate in sediment pore waters is strongly adsorbed by the metal-enriched phases. Consequently, fluxes of phosphorus from the sediments to overlying waters are very small and contribute to the oligotrophic nature of the Toolik Lake aquatic system. Toolik Lake contains an unusual type of lacustrine sediment, and in many ways the sediments are similar to those found in oligotrophic oceanic environments.

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Sprint interval training (SIT) can elicit improvements in aerobic and anaerobic capacity. While variations in SIT protocols have been investigated, the influence of social processes cannot be overlooked. As research supports the use of groups to influence individual cognitions and behaviours, the current project assessed the effectiveness of a group-based intervention with participants conducting SIT. Specifically, 53 amateur athletes (age, 21.9 ± 2.9 years; 53% females) took part in a 4-week training program (3 sessions per week, 30-s “all-out” efforts with 4 min active recovery, repeated 4–6 times per session), and were assigned to “true group”, aggregate, or individual conditions. Results indicated no significant differences between groups for the physiological measures. With regards to training improvements from baseline for all participants— regardless of condition — significant main effects for time were identified for maximal oxygen uptake (2.5–2.8 mL·kg−1·min−1, p < 0.001, η2 = 0.03), time-trial performance (14–32 s, p < 0.001, η2 = 0.37), and anaerobic power (1.1–1.7 k·h−1, p < 0.001, η2 = 0.66). With regards to the psychological measures, significant main effects between groups were found for motivation (p = 0.033, η2 = 0.13), task self-efficacy (p = 0.018, η2 = 0.15), and scheduling self-efficacy (p = 0.003, η2 = 0.22). The true group experienced greater improvements in motivation than the individual condition, but the aggregate and individual conditions demonstrated greater increases in task and scheduling self-efficacy. Though the SIT paradigm employed induced training improvements similar to previous work, the group intervention was not able to further these improvements

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There is a large degree of heterogeneity in response to regular physical activity at the individual level, with some exhibiting no or very small improvements in VO2peak following highly controlled exercise training. The purpose of this thesis was to examine individual variation in VO2peak response to sprint interval training (SIT) in relation to individual responses to multiple measures of peripheral physiological adaptation. Specifically, VO2peak, capillary density, fibre-specific SDH content, and type I fibre % were measured in 23 young, healthy, recreationally active males before and after 4 weeks SIT (Tabata protocol 4 x per week). The key findings of this experiment included that, when separated into tertiles of VO2peak response, the high (HI) and low (LO) groups differed significantly in VO2peak change after training. Secondly, there was no difference between HI and LO groups for response in any of capillary density, fibre-specific SDH content, or fibre type %, with no correlation found between individual VO2peak response and changes in any measured peripheral variable. Together, these results confirm that individuals respond heterogeneously to SIT and suggest that this heterogeneity does not result from differences in individual changes in capillary density, fibre-specific SDH content or type I fibre %. It is speculated that some other combination of peripheral physiological adaptation must explain variability in VO2peak response to 4 weeks of SIT.