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1.
Symbolic dynamics is a powerful tool for studying complex dynamical systems. So far many techniques of this kind have been proposed as a means to analyze brain dynamics, but most of them are restricted to single-sensor measurements. Analyzing the dynamics in a channel-wise fashion is an invalid approach for multisite encephalographic recordings, since it ignores any pattern of coordinated activity that might emerge from the coherent activation of distinct brain areas. We suggest, here, the use of neural-gas algorithm (Martinez et al. in IEEE Trans Neural Netw 4:558–569, 1993) for encoding brain activity spatiotemporal dynamics in the form of a symbolic timeseries. A codebook of k prototypes, best representing the instantaneous multichannel data, is first designed. Each pattern of activity is then assigned to the most similar code vector. The symbolic timeseries derived in this way is mapped to a network, the topology of which encapsulates the most important phase transitions of the underlying dynamical system. Finally, global efficiency is used to characterize the obtained topology. We demonstrate the approach by applying it to EEG-data recorded from subjects while performing mental calculations. By working in a contrastive-fashion, and focusing in the phase aspects of the signals, we show that the underlying dynamics differ significantly in their symbolic representations.  相似文献   

2.
Using a symbolic dynamics and a surrogate data approach, we show that the language exhibited by common fruit flies Drosophila (‘D.’) during courtship is as grammatically complex as the most complex human-spoken modern languages. This finding emerges from the study of fifty high-speed courtship videos (generally of several minutes duration) that were visually frame-by-frame dissected into 37 fundamental behavioral elements. From the symbolic dynamics of these elements, the courtship-generating language was determined with extreme confidence (significance level > 0.95). The languages categorization in terms of position in Chomsky’s hierarchical language classification allows to compare Drosophila’s body language not only with computer’s compiler languages, but also with human-spoken languages. Drosophila’s body language emerges to be at least as powerful as the languages spoken by humans.  相似文献   

3.
We describe here two patients with tinea corporis exhibiting black dot ringworm (BDR). A cluster of black dots was observed on the extensor surfaces of the extremities of two rather hairy male patients, a 15-year-old judo practitioner and a 26-year-old combined martial arts fighter, during treatment of tinea corporis with topical antimycotics. Direct KOH examination showed that the black dots were composed of degenerated hair with numerous arthroconidia and were indistinguishable from BDR of tinea capitis. Trichophyton tonsurans was isolated from the dots of both patients. Although they were diagnosed with tinea corporis, they required 2–3 months of treatment with oral terbinafine. Dermatologists should be aware that BDR can appear on areas of the skin other than the scalp.  相似文献   

4.
ABSTRACT

This article is a review and thematic analysis of the 2014 National Core Arts Standards (NCAS). Historically, there exists a gap between the arts and assessment-based educational practices. Thematic analysis of the NCAS reveals a policy striving to bridge the gap between the way arts educators envision arts in schools, and the current reality of assessment-based schooling in the United States. This policy could become the foundation for the recognition of the arts as academically rigorous subject matter, capable of existing and thriving in an assessment-oriented world; it remains to be seen as to how and if arts educators will use and adapt NCAS. Is the NCAS merely a symbolic policy or does it have the support behind it to be a material policy that truly creates change in the educational system?  相似文献   

5.
We argue that enhanced play may have contributed to the emergence of complex language systems in modern humans (Homo sapiens). To support this idea, we first discuss evidence for an expansion of playing behavior connected to the extended childhood of modern human children, and the potential of this period for the transmission of complex cultural traits, including language. We then link two of the most important functions of play—exploration and innovation—to the potential for cumulative cultural evolution in general and for the emergence of complex language in particular. If correct, the shorter childhood of Neanderthals—involving restrictions on time to experiment and innovate—may have restricted their language (and other symbolic) system/s. Consequently, fully investigating the role that play may have had in the transmission of language and the development of symbolic cultures in both modern humans and Neanderthals provides a new avenue of research for Paleolithic archaeology and related disciplines.  相似文献   

6.
Observations on petalial asymmetry for 190 hominoid endocasts are reported, and their statistical differences assessed. While all taxa of hominoids show asymmetries to various degrees, the patterns or combinations of petalial asymmetries are very different, with fossil hominids and modern Homo sapiens showing an identical pattern of left-occipital, right-frontal petalias, which contrasts with those found normally in pongids. Of the pongids, Gorilla shows the greater degree of asymmetry in left-occipital petalias. Only modern Homo and hominids (Australopithecus, Homo erectus, Neandertals) show a distinct left-occipital, right-frontal petalial pattern. Analysis by x2 statistics shows the differences to be highly significant. Due to small sample size and incompleteness of endocasts, small-brained hominids, i.e., Australopithecus, are problematical. To the degree that gross petalial patterns are correlated with cognitive task specialization, we speculate that human cognitive patterns evolved early in hominid evolution and were related to selection pressures operating on both symbolic and spatiovisual integration, and that these faculties are corroborated in the archaeological record.  相似文献   

7.
Ian Tattersall 《Evolution》2009,2(4):584-589
Human beings are unusual in many ways but perhaps most strikingly in their unique symbolic form of processing information about the world around them. Although based on a long and essential evolutionary history, the modern human cognitive style is not predicted by that history: it is emergent rather than the product of an incremental process of refinement. Homo sapiens is physically very distinctive and is clearly the result of a significant developmental reorganization with ramifications throughout the skeleton and presumably beyond. It is reasonable to suppose that the neural underpinnings of symbolic thought were acquired in this reorganization. However, the fossil and archeological records indicate that the first anatomically recognizable members of the species substantially predated its first members who behaved in a demonstrably symbolic manner. Thus, while the biological potential for symbolic thinking most likely arose in the morphogenetic event that gave rise to H. sapiens as a distinctive anatomical entity, this new capacity was evidently exaptive, in the sense that it had to await its “discovery” and release through a cultural stimulus. Plausibly, this stimulus was the invention of language. One expression of symbolic reasoning is the adoption of technological change in response to environmental challenges, contrasting with earlier responses that typically involved using existing technologies in new ways. As climates changed at the end of the last Ice Age, the new technophile proclivity was expressed in a shift toward agriculture and sedentary lifestyles: a shift that precipitated a fundamentally new (and potentially self-destructive) relationship with nature. Thus, both of what are arguably the two most radical (and certainly the most fateful) evolutionary innovations in the history of life (symbolic thinking and sedentary lifestyles) were both very recent occurrences, well within the (so far rather short) tenure of H. sapiens.  相似文献   

8.
31 men and 10 women of the German national cadre or cadres of the federal states (average age 22.3+/-6.1 years), who practised the still relatively new martial arts sports Ju-Jutsu for 8.9+/-4.3 years with 6.2+/-3.6 h training/week, were investigated by means of kinanthropometric methods and compared to 31 male and 10 female hobby martial arts athletes (average age 29.2+/-7.0 years), who practised Jeet Kune Do, Ju-Jutsu or Wing Chun since 8.2+/-7.8 years with 4.1+/-1.7 training hours/week. In the somatochart after Parnell the fighters were placed more endomesomorphic than the hobby sportsmen. In Conrad's chessboard sample graphics the fighters concentrate on the leptomorph half including the metromorph corridor. Remarkable above all is here a placement of the weight class average values toward the pyknomorph hyperplastic quadrant. Also in Knussmann's body build typognosis the weight classes reveal a clear tendency from the coordinates -13/0.5 to -8.3/6.5 in the superleptomorph area. The body fat percentage varies from 17.4 % (male competitors) to 21.8 % (male non-competitors) and 21.2 % (female competitors) to 23.6 % (female non-competitors), which appears still optimizable in comparison to other martial arts collectives.  相似文献   

9.
The five articles in this Special Issue are introduced by contextualising them broadly within feminist poststructuralist, postcolonial and anthropological approaches. After a brief exploration of methodologies that link ethnography with poetics and historical analysis, a general theoretical critique of modern Western forms of agency, especially liberal notions of autonomous rational choice, is offered. Western philosophy and theory, argues the author, have implications well beyond social formations in the West and she outlines their impacts on the agency of women in Asian societies. While cautioning against the pitfalls of both under and overvaluing agency, the author then offers a reconsideration of its analytical utility. Agency needs to address the gaps between everyday reflection and practices and hegemonic discourses or symbolic structures. In this gap, where women who fall outside the parameters of dominant notions of womanhood are considered ‘unstable’, both resistance and constraint are possible. Dominant discourses certainly have durable effects but their tools and symbols have been reinscribed to produce agency in hybrid forms. Agency is thus thought to arise from within existing societal discourses and symbolic structures rather than in opposition to them. In this process multiple positionings for women, all of which are performative, are created. These reconsiderations of agency are mirrored in the articles which follow. Agency in its modern forms is deemed inadequate by these authors to explain the agency of women in Asia. Rather than proposing a hierarchy of agency in its significant and insignificant forms, the authors in this Issue provide much needed accounts of socially and culturally situated agency, significant in both their breadth and depth.  相似文献   

10.
This study investigated a means of quantifying urinary myoglobin using a novel reverse-phase high-performance liquid chromatography (RP–HPLC) method that is an alternative measure of exercise-induced muscle damage. It also investigated the effect of storage and alkalization on urinary myoglobin stability issues. An RP–HPLC method was validated by precision and repeatability experiments. Myoglobin stability was determined through spiked urine samples stored at various temperatures over an 8-week period using alkalization and dilution in a pH 7.0 buffer. The method was validated with urine collected from mixed martial arts fighters during a competition and training session. The method produced linearity from 5 to 1000 μg/ml (R2 = 0.997), intra- and inter-assay coefficients of variation from 0.32 to 2.94%, and a lower detection limit of 0.2 μg/ml in the final dilution and 2 μg/ml in the original urine sample. Recovery ranged from 96.4 to 102.5%, myoglobin remained stable at 4 °C when diluted in a pH 7.0 buffer after 20 h, and a significant increase (P < 0.01) and an identifiable peak were observed following a mixed martial arts contest and training session. Storage length and conditions had significant effects (P < 0.05) on stability. The method's simplicity and noninvasive nature means it can be used as an alternative muscle damage assay following exercise and trauma.  相似文献   

11.
Ian Tattersall 《Evolution》2010,3(3):399-402
Human beings are distinguished most strikingly by their unique “symbolic” way of processing information about the world. Although based on a long evolutionary history, the modern human cognitive style is not predicted by that history. It is not the product of a process of incremental refinement but is instead “emergent,” representing an entirely distinct level of complexity. Physically, Homo sapiens is very distinctive, its peculiarities clearly resulting from a significant developmental reorganization with numerous skeletal ramifications and quite plausibly others as well. It seems reasonable to suppose that the structural underpinnings of symbolic thought were acquired in this reorganization. Still, the fossil and archaeological records indicate that the first anatomically recognizable members of the species predated the first humans who behaved in a demonstrably symbolic manner. So while the biological potential for symbolic thinking most likely arose in the morphogenetic event that gave rise to H. sapiens as a distinctive anatomical entity, this new capacity was evidently exaptive, in the sense that it had to await its “discovery” and expression, clearly through a cultural stimulus that was plausibly the invention of language. One manifestation of symbolic reasoning is the adoption of technological change in response to environmental challenges, in contrast to earlier responses that typically used existing technologies in new ways. As climates changed at the end of the last Ice Age, this new technophile proclivity was expressed in a shift toward agriculture and sedentary lifestyles, precipitating a fundamentally new (and potentially self-destructive) relationship with Nature. Both of the two most radical and fateful evolutionary innovations in the history of life (symbolic thinking and sedentary lifestyles) were thus very recent occurrences, well within the short tenure of H. sapiens.  相似文献   

12.
Morphological variations of the deciduous dentition are as useful as those of the permanent dentition for determining the biological affinities of human populations. This paper provides material on morphological variations of deciduous teeth of the prehistoric Japanese population from the Late and the Latest Jomon Period (ca. 2000–ca. 300 B.C.). The expression of nonmetric traits of the deciduous teeth in the Jomon sample shows a closer affinity with modern Japanese and Native American samples than with American White, Asiatic Indian, and African samples. However, the frequency of shoveling in deciduous upper incisors in the Jomon sample is lower than those in modern Japanese and Native American samples. The Jomon sample also expresses a much higher frequency of cusp 6 in deciduous lower second molars than seen in modern Japanese, Ainu, and Native American samples. The frequency in the Jomon sample is equal to that in the Australian Aboriginal sample, which shows cusp 6 most frequently among the samples compared. A somewhat low incidence of incisor shoveling in the Jomon sample was also reported in the permanent dentition (Turner [1976] Science 193:911–913, [1979] Am. J. Phys. Anthropol. 51:619–635, [1987] Am. J. Phys. Anthropol. 73:305–321, [1990] Am. J. Phys. Anthropol. 82:295–317; T. Hanihara [1992] Am. J. Phys. Anthropol. 88:163–182, 88:183–196). However, the frequency of cusp 6 in the Jomon sample shows no significant difference from those of Northeast Asian or Native American samples in the permanent dentition (Turner [1987] Am. J. Phys. Anthropol. 73:305–321; T. Hanihara [1992] Am. J. Phys. Anthropol. 88:1–182, 88:183–196). Evidently, some nonmetric traits express an inter-group difference only in the deciduous dentition. © 1995 Wiley-Liss, Inc.  相似文献   

13.
A recent study suggested that increased copy numbers of the AMY2B gene might be a crucial genetic change that occurred during the domestication of dogs. To investigate AMY2B expansion in ancient breeds, which are highly divergent from modern breeds of presumed European origins, we analysed copy numbers in native Japanese dog breeds. Copy numbers in the Akita and Shiba, two ancient breeds in Japan, were higher than those in wolves. However, compared to a group of various modern breeds, Akitas had fewer copy numbers, whereas Shibas exhibited the same level of expansion as modern breeds. Interestingly, average AMY2B copy numbers in the Jomon‐Shiba, a unique line of the Shiba that has been bred to maintain their appearance resembling ancestors of native Japanese dogs and that originated in the same region as the Akita, were lower than those in the Shiba. These differences may have arisen from the earlier introduction of rice farming to the region in which the Shiba originated compared to the region in which the Akita and the Jomon‐Shiba originated. Thus, our data provide insights into the relationship between the introduction of agriculture and AMY2B expansion in dogs.  相似文献   

14.
This paper examines the symbolic properties and cultural relevance of latah, a behavioral state noted in Malaya and Indonesia since the 19th Century. Most interpretations of latah have been psychological, latah being perceived as a mental disorder. In the following, it is concluded that latat is intimately related to other aspects of Malayo-Indonesian culture and that it is a well-known cultural pattern and not a mental disorder as such, though it may occur among persons, largely women, in a socially and psychologically marginal situation. Latah is a symbolic representation of marginality, and it is as appropriate to certain mythological and religious figures as to the socially marginal.  相似文献   

15.
Five polymorphic microsatellite markers were developed in the Japanese conger eel (Conger myriaster) to understand the recruitment mechanisms and population structure of this species, the spawning sites and migration routes of which are unknown. Three of the loci were highly polymorphic and will serve as powerful tools for detailed population studies of the Japanese conger eel. One of the other two loci showed significant departure from Hardy–Weinberg equilibrium and the other showed low allelic diversity.  相似文献   

16.

Background

The etiology of complex diseases is due to the combination of genetic and environmental factors, usually many of them, and each with a small effect. The identification of these small-effect contributing factors is still a demanding task. Clearly, there is a need for more powerful tests of genetic association, and especially for the identification of rare effects

Results

We introduce a new genetic association test based on symbolic dynamics and symbolic entropy. Using a freely available software, we have applied this entropy test, and a conventional test, to simulated and real datasets, to illustrate the method and estimate type I error and power. We have also compared this new entropy test to the Fisher exact test for assessment of association with low-frequency SNPs. The entropy test is generally more powerful than the conventional test, and can be significantly more powerful when the genotypic test is applied to low allele-frequency markers. We have also shown that both the Fisher and Entropy methods are optimal to test for association with low-frequency SNPs (MAF around 1-5%), and both are conservative for very rare SNPs (MAF<1%)

Conclusions

We have developed a new, simple, consistent and powerful test to detect genetic association of biallelic/SNP markers in case-control data, by using symbolic dynamics and symbolic entropy as a measure of gene dependence. We also provide a standard asymptotic distribution of this test statistic. Given that the test is based on entropy measures, it avoids smoothed nonparametric estimation. The entropy test is generally as good or even more powerful than the conventional and Fisher tests. Furthermore, the entropy test is more computationally efficient than the Fisher's Exact test, especially for large number of markers. Therefore, this entropy-based test has the advantage of being optimal for most SNPs, regardless of their allele frequency (Minor Allele Frequency (MAF) between 1-50%). This property is quite beneficial, since many researchers tend to discard low allele-frequency SNPs from their analysis. Now they can apply the same statistical test of association to all SNPs in a single analysis., which can be especially helpful to detect rare effects.  相似文献   

17.
This study examines implicit sequence learning impairments that may indicate at‐risk cerebellar profiles proposed to underlie some aspects of subtle cognitive and affective dysfunctions found among female fragile X mental retardation 1 (FMR1) premutation (PM)‐carriers. A total of 34 female PM‐carriers and 33 age‐ and intelligence‐matched controls completed an implicit symbolically primed serial reaction time task (SRTT) previously shown to be sensitive to cerebellar involvement. Implicit learning scores indicated a preservation of learning in both groups; however, PM‐carriers demonstrated poorer learning through significantly elevated response latencies overall and at each specific block within the symbolic SRTT. Group comparisons also revealed a core deficit in response inhibition, alongside elevated inattentive symptoms in female PM‐carriers. Finally, strong and significant associations were observed between poor symbolic SRTT performance and executive, visuospatial and affective deficits in the PM‐carrier group. These associations remained strong even after controlling motor speed, and were not observed in age‐ and intelligence quotient‐matched participants. The findings implicate cerebellar non‐motor networks subserving the implicit sequencing of responses in cognitive–affective phenotypes previously observed in female PM‐carriers. We contend that symbolic SRTT performance may offer clinical utility in future pharmaceutical interventions in female PM‐carriers .  相似文献   

18.
We quantitatively examined the differences in the size and proportion of the Japanese macaque (Macaca fuscata) by comparing the Early Jomon specimens from Torihama shell-midden, Fukui Prefecture and modern specimens from Fukui Prefecture. The purpose of this study was to explore the temporal change in the proportion and size of teeth of the Japanese macaques based on the quantified data. The result of measurements of lower premolars and molars demonstrated that sexual dimorphism was evident only among the modern specimens where the females were significantly smaller than males. The size of male Torihama specimens was within the range of the modern population, whereas the size of the female Torihama specimens was significantly larger than the modern female population. The proportional pattern of premolars and molars for male and female Torihama specimens also differed. The results may suggest a possible difference in the degree of size reduction between males and females since the last glacial period.Morphometric analysis of mandibular cheek teeth from Torihama Shell-midden  相似文献   

19.
This symposium on my book, The Specter of Race: How Discrimination Haunts Western Democracy (Princeton, 2018) provides an opportunity to engage specialists in classical and modern political theory and philosophy, comparative racial and ethnic politics, and political sociology who have provided commentary on different aspects of the two overarching arguments intertwined in The Specter of Race; how students of democracy have largely ignored how racial and ethno-national hierarchy has been historically tethered to its practice , and how students of comparative politics have, for the most part, ignored how these hierarchies have informed the very development of modern democracies.  相似文献   

20.
Aim:  To determine the antimicrobial resistance of the Japanese probiotics available in the market without a pharmacist’s supervision. Methods and Results:  A total of 43 isolates were obtained from 40 samples of probiotics (30 dairy products and 10 products in tablet form). Isolates were identified using 16S rRNA gene sequencing and tested for their susceptibility to 14 antimicrobials. They were screened using PCR for some antibiotic resistance genes. Inactivation of cefepime, clarithromycin and vancomycin by different inocula of 11 strains was evaluated using the antibiotic inactivation bioassay. None of the dairy probiotics showed a level of constitutive resistance or carried inducible resistance genes, making them suitable to be administrated with macrolides. Among the probiotics in tablet form only Enterococcus faecium strains carrying the msrC gene showed an MIC90 of 4 μg ml?1. Extended‐spectrum β‐lactams, tetracyclines and ampicillin exhibited powerful germicidal activity against the vast majority of the probiotic strains. Conclusions:  There is a limited choice of the Japanese probiotics that can be administered with clinically used antibiotics. Significance and Impact of the Study:  Japanese probiotics are widely distributed all over the world. Through the findings of our study, we have attempted to provide guidance for clinicians interested in using the Japanese probiotics in combination with antibiotics.  相似文献   

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