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Katharine MacDonald Fulco Scherjon Eva van Veen Krist Vaesen Wil Roebroeks 《Proceedings of the National Academy of Sciences of the United States of America》2021,118(31)
Control of fire is one of the most important technological innovations within the evolution of humankind. The archaeological signal of fire use becomes very visible from around 400,000 y ago onward. Interestingly, this occurs at a geologically similar time over major parts of the Old World, in Africa, as well as in western Eurasia, and in different subpopulations of the wider hominin metapopulation. We interpret this spatiotemporal pattern as the result of cultural diffusion, and as representing the earliest clear-cut case of widespread cultural change resulting from diffusion in human evolution. This fire-use pattern is followed slightly later by a similar spatiotemporal distribution of Levallois technology, at the beginning of the African Middle Stone Age and the western Eurasian Middle Paleolithic. These archaeological data, as well as studies of ancient genomes, lead us to hypothesize that at the latest by 400,000 y ago, hominin subpopulations encountered one another often enough and were sufficiently tolerant toward one another to transmit ideas and techniques over large regions within relatively short time periods. Furthermore, it is likely that the large-scale social networks necessary to transmit complicated skills were also in place. Most importantly, this suggests a form of cultural behavior significantly more similar to that of extant Homo sapiens than to our great ape relatives. 相似文献
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Ledowski T Albus S Stein J Macdonald B 《Journal of clinical monitoring and computing》2011,25(6):371-376
Aim of this prospective randomized study was to determine the influence of the electrode surface area and sampling time on
the accuracy of the number of fluctuations in skin conductance per second to distinguish different states of acute pain. These
methodological issues have been previously suggested as an explanation for contradictory data related to the accuracy of the
skin conductance monitor. A total of 541 pain ratings on a numeric rating scale (0–10) were obtained from 120 adult postoperative
patients. The number of fluctuations in skin conductance per second was recorded using two different electrode types (surface
area 254 vs. 474 mm2) and sampling times (7.5 vs. 30 s). A longer sampling time did result in higher values for the number of fluctuations in
skin conductance per second, though without improving its accuracy to distinguish different states of pain. However, the latter
was found improved when the smaller surface area electrodes were used. A combination of small surface area electrodes and
a 30 s sampling time resulted in the highest area under the curve in the receiver operating curve analysis of the method to
identify states of moderate to severe pain (numeric rating scale > 3): 0.68 vs. e.g. 0.55 [data from all patients combined]).
We conclude that the type of electrodes used but only to a lesser degree the sampling time influence the accuracy of the number
of fluctuations in skin conductance per second to identify states of moderate or severe postoperative pain. 相似文献
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Verpooten GA Aerts A Coen N Vancayzeele S Hermans C Bowles J MacDonald K Abraham I Lee CS 《International journal of clinical practice》2011,65(1):54-63
Aims: The ‘DRIVER’ study was designed to investigate the ‘real‐world’ effectiveness of aliskiren‐based treatment of hypertension. This article reports the 180‐day blood pressure (BP) outcomes, and the multilevel (physician‐ and patient‐level) determinants thereof. Methods and results: DRIVER was a prospective, observational, open‐label, multi‐centre, pharmaco‐epidemiologic study of hypertensive patients treated with aliskiren in whom prior treatment failed or was not tolerated. 2070 patients (enrolled by 426 physicians) were enrolled; 1695 patients (81.9%) completed the 180‐day aliskiren treatment period. Mean patient age was 64.2 ± 12.1 years; 53.7% were men, 25.3% diabetic and 40.7% had a high or very high cardiovascular (CV) risk. At 180 days, the mean ± SD reductions in systolic and diastolic BP were ?22.9 ± 16.7 mmHg and ?10.5 ± 10.9 mmHg respectively (both p < .001). 2007 and 2009 guideline‐defined BP control was achieved in 36.4% and 56.3% of patients, respectively (both p < .001). 64.2% of eligible patients had a reduction in CV risk (p < .001). A physician‐level class effect was responsible for 22.8% and 28.1% of variability in systolic and diastolic BP, respectively, for 20.1% of variability in BP control, and for 16.1% of variability in the reduction of CV risk. Both patient‐ (e.g. adherence) and physician‐related factors (e.g. age and knowledge) were significant in profiling best response to treatment with aliskiren. Adverse events reported in this article were consistent with the aliskiren scientific leaflet. Conclusion: Aliskiren is safe and effective in reducing BP, improving BP control and reducing global CV risk in a ‘real‐world’ setting and for patients in whom prior treatment failed or was not tolerated. Optimising treatment adherence and strategic medical education may be ways of improving BP outcomes in patients with hypertension. 相似文献
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Silverstein SM Keane BP Barch DM Carter CS Gold JM Kovács I MacDonald A Ragland JD Strauss ME 《Schizophrenia bulletin》2012,38(1):125-134
The Cognitive Neuroscience Treatment Research to Improve Cognition in Schizophrenia initiative highlighted a contour integration test as a promising index of visual integration impairment because of its well-established psychometric properties; its prior validation in healthy adults, patients, and nonhuman primates; and its potential sensitivity to treatment effects. In this multisite study, our goals were to validate the task on the largest subject sample to date, clarify the task conditions and number of trials that best discriminate patients from controls, and determine whether this discrimination can occur in standard clinical trial settings. For our task, subjects briefly observed a field of disconnected, oriented elements and attempted to decide whether a subset of those elements formed a leftward- or rightward-pointing shape. Difficulty depended on the amount of orientational jitter that was added to the shape's elements. Two versions of this Jittered Orientation Visual Integration task (JOVI) were examined. Study 1 did not reveal between-group differences in threshold (ie, the jitter magnitude needed to reach a performance level of ~80%), but this likely owed to the wide sampling distribution of jitter levels and resulting floor/ceiling effects in many conditions. Study 2 incorporated a narrower range of difficulty levels and revealed lower thresholds (worse performance) among patients (p < .001). This group difference remained even when only the first half of the trials was analyzed (p = .001). Thus, the JOVI-2 provides a brief, sensitive measure of visual integration deficits in schizophrenia. Neural implications and potential future applications of the JOVI are discussed. 相似文献
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