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关键词： Neocortex   Categorisation   Short-term memory   Top-down attention   Memory recall   Pyramidal cells   Learning  

摘要： Neocortical pyramidal cells have three key classes of excitatory input: forward inputs from the previous cortical area (or thalamus);recurrent collateral synapses from nearby pyramidal cells;and backprojection inputs from the following cortical area. The neocortex performs three major types of computation: (1) unsupervised learning of new categories, by allocating neurons to respond to combinations of inputs from the preceding cortical stage, which can be performed using competitive learning;(2) short-term memory, which can be performed by an attractor network using the recurrent collaterals;and (3) recall of what has been learned by top-down backprojections from the following cortical area. There is only one type of excitatory neuron involved, pyramidal cells, with these three types of input. It is proposed, and tested by simulations of a neuronal network model, that pyramidal cells can implement all three types of learning simultaneously, and can subsequently usefully categorise the forward inputs;keep them active in short-term memory;and later recall the representations using the backprojection input. This provides a new approach to understanding how one type of excitatory neuron in the neocortex can implement these three major types of computation, and provides a conceptual advance in understanding how the cerebral neocortex may work.

关键词： 3D model retrieval   Ontology   Semantic information   Object part segmentation   Similarity measure  

摘要： 3D model retrieval is useful for reusing designs in manufacturing industry. Traditionally, 3D model retrieval has been implemented only in low-level information such as geometry, color, and texture. However high-level semantic information should be used for more accurate retrieval. In this study, a 3D geometry is divided into several parts using PointNet and then the local ontology is constructed by summarizing the characteristics of each part. Then part align similarity, lemma similarity, name similarity, part location similarity, and part size similarity are calculated. Using the values of these similarities, 3D models are retrieved from input query model. This comprehensive retrieval that includes all the similarities is more balanced and shows better performance in nameless models than considering only partial similarities. Through the method in this paper, high-level information and low-level information can be used simultaneously for 3D model retrieval.

关键词： authentication   crystallization   differential scanning calorimetry   Iberian pig   polymorphism   synchrotron radiation   X-ray diffraction  

摘要： High-commercial-value products are often susceptible to food fraud. Among them, Iberian dry-cured ham is highly appreciated due to its particular and sensory, but also nutritional, properties. There are four different Iberian ham categories (namely bellota, recebo, cebo de campo and cebo), which directly depend on the rearing system of the pig during the last stage of the fattening phase. However, there is still a lack of a normalized and robust method capable of authenticating the different product categories and, therefore, preventing mislabeling. In the present work, we characterized the polymorphic behavior of raw (before curing) lipid extracts belonging to the four categories of Iberian pig. A total of 80 different samples were analyzed by DSC, and synchrotron radiation XRD experiments were carried out for selected ones. The results obtained showed that bellota and recebo categories exhibited essentially the same crystallization and polymorphic behavior and this was significantly different (p < 0.05) from that of cebo de campo and cebo. The latter exhibited higher crystallization and melting temperatures than bellota and recebo samples, due to the occurrence of an additional beta '-2L polymorphic form. By considering the differences in rearing systems of pigs belonging to the different categories, we concluded that the key factor which determined the polymorphism of Iberian pig lipid extracts was not the physical exercise practiced by the pig, but the inclusion of acorns in the feeding system. This work demonstrated that thermal and crystallographic techniques, like DSC and XRD, may be promoted to be used as fingerprinting tools for the authentication of high-value food products.

关键词： age   context   generations   millennials   validity  

摘要： This provocation challenges the use of generational categories as a valid and useful basis for the development of human resource management (HRM) research and practice. We present two provocations. First, that a focus solely on year of birth as a driver of attitudes, values and behaviours is wholly inadequate. Second, we go beyond existing empirical challenges to argue that any approach to the study of generations that focuses solely on generational categories should be abandoned. We consider the theoretical basis for generations, together with specific examples from empirical studies to show how the current reliance on largely unsubstantiated categories leaves even longitudinal studies unable to make an effective contribution to this field. We draw on cross-disciplinary insights to consider the implications for academic research and for HRM practice, showing how the current approach limits the usefulness of findings and suggesting a potential way forward.

关键词： Thyroid cancer   FNA   Bethesda system   Reproducibility   Cytology  

摘要： Purpose Equivocal categories (III, IV, V) of the Bethesda System for Reporting Thyroid Cytology (BSRTC) are characterized by high variability of the estimated risk of malignancy. The aim of the study was to analyze the reproducibility of classification of nodules into an equivocal category and the frequency of malignancy (FoM) observed in such categories. Methods Five experienced cytopathologists from three centers (A, B, C) independently performed reclassification of smears obtained from 213 thyroid nodules with equivocal routine cytology and known results of the postoperative histopathological examination. Results The interobserver agreement among all cytopathologists was poor, with a Krippendorff's alpha coefficient equaling 0.34. The intra-center agreement was higher than the inter-center (fair vs poor). Pathologists of the center A classified smears into categories II and III significantly less often and categories IV and V more often than pathologists of centers B and C. The joint FoM of nodules classified into any of categories IV-VI (regarded as an indication for surgery) was different among centers (A: 40.0%, B: 66.7%, C: 80.6%). The FoM of category III nodules with features of nuclear atypia (AUS) in center B and C was two times higher than that of other nodules of category III (FLUS), while in center A the FoM was similar. Conclusions The use of published data on the risk of malignancy in nodules of particular BSRTC categories without concern for the uniqueness of the diagnostic center may lead to erroneous conclusions.

关键词： Category O   Koszul duality   Zuckerman functor  

摘要： The parabolic category O for affine gl(N) at level -N- eadmits a structure of a categorical representation of (sl(e)) over tilde with respect to some endofunctors Eand F. This category contains a smaller category Athat categorifies the higher level Fock space. We prove that the functors Eand Fin the category Aare Koszul dual to Zuckerman functors. The key point of the proof is to show that the functor Ffor the category Aat level -N- ecan be decomposed in terms of the components of the functor Ffor the category Aat level -N- e - 1. To prove this, we use the following fact from [9]: a category with an action of (sl) over tilde (e+1) contains a (canonically defined) subcategory with an action of (sl) over tilde (e). We also prove a general statement that says that in some general situation a functor that satisfies a list of axioms is automatically Koszul dual to some sort of Zuckerman functor. (c) 2021 Published by Elsevier Inc.

关键词： Singularity category   Singular equivalence   Cyclic quotient singularity   Non-Gorenstein   Triangle equivalence   Heller stabilization of left   triangulated categories  

摘要： We construct a triangle equivalence between the singularity categories of two isolated cyclic quotient singularities of Krull dimensions two and three, respectively. This is the first example of a singular equivalence involving connected commutative algebras of odd and even Krull dimension. In combination with Orlov's localization result, this gives further singular equivalences between certain quasi-projective varieties of dimensions two and three, respectively. (c) 2021 Elsevier Inc. All rights reserved.

摘要： What are the origins of musical rhythm? One approach to the biology and evolution of music consists in finding common musical traits across species. These similarities allow biomusicologists to infer when and how musical traits appeared in our species1 . A parallel approach to the biology and evolution of music focuses on finding statistical universals in human music2 . These include rhythmic features that appear above chance across musical cultures. One such universal is the production of categorical rhythms3 , defined as those where temporal intervals between note onsets are distributed categorically rather than uniformly2 , 4 , 5 . Prominent rhythm categories include those with intervals related by small integer ratios, such as 1:1 (isochrony) and 1:2, which translates as some notes being twice as long as their adjacent ones. In humans, universals are often defined in relation to the beat, a top-down cognitive process of inferring a temporal regularity from a complex musical scene1 . Without assuming the presence of the beat in other animals, one can still investigate its downstream products, namely rhythmic categories with small integer ratios detected in recorded signals. Here we combine the comparative and statistical universals approaches, testing the hypothesis that rhythmic categories and small integer ratios should appear in species showing coordinated group singing3 . We find that a lemur species displays, in its coordinated songs, the isochronous and 1:2 rhythm categories seen in human music, showing that such categories are not, among mammals, unique to humans3 .

关键词： Community composition   Disturbance   Functional guild   Fungal biodiversity   Mexico   Tropical dry forest  

摘要： Climate change is increasing the frequency and intensity of catastrophic events such as hurricanes. Soil microbial communities regulate geochemical cycles and other important ecosystem processes. How the hurricanes affect soil microbial communities and their function, however, is largely unknown. Our aim was to describe the impact of a category 4 hurricane (Patricia) on the soil fungal community structure and diversity in a Mexican tropical dry forest. Soil fungal community was inferred sequencing the ITS2 rDNA of composite soil samples taken in a time series ranging one year before and two years after the hurricane. OTU richness before the hurricane and in the first sampling after were comparable, however a 20-40% decrease in richness was observed in later sampling times. There were also taxonomic shifts associated with the disturbance, changing from a higher richness and abundance of Ascomycota fungi to greater dominance of Basidiomycota and Glomeromycota fungi post hurricane. Arbuscular mycorrhizal fungi and plant pathogens diversity increased immediately after the hurricane but decreased in subsequent years. Approximately 7% of the soil community, primarily composed of saprotrophic fungi, persisted across the hurricane and the harsh seasonality of this ecosystem. Soil fungal community was affected by the hurricane but had function stability and resilience through years.

关键词： EEG decoding   Categorical bias   Visual working memory  

摘要： Previous research demonstrated that visual representations in working memory exhibit biases with respect to the categorical structure of the stimulus space. However, a majority of those studies used behavioral measures of working memory, and it is not clear whether the working memory representations per se are influenced by the categorical structure or whether the biases arise in decision or response processes during the report. Here, I applied a multivariate decoding technique to EEG data collected during working memory tasks to determine whether neural activity associated with the representations in working memory is categorically biased prior to the report. I found that the decoding of spatial working memory was biased away from the nearest cardinal location, consistent with the biases observed in the behavioral responses. In a follow-up experiment which was designed to prevent the use of a response preparation strategy, I found that the decoding still exhibited categorical biases. Together, these results provide neural evidence that working memory representations themselves are categorically biased, imposing important constraints on the models of working memory representations.