Scene perception involves extracting the identities of the objects comprising a scene in conjunction with their configuration (the spatial layout of the objects in the scene). How object identity and ...configuration information is weighted during scene processing and how this weighting evolves over the course of scene processing however, is not fully understood. Recent developments in convolutional neural networks (CNNs) have demonstrated their aptitude at scene processing tasks and identified correlations between processing in CNNs and in the human brain. Here we examined four CNN architectures (Alexnet, Resnet18, Resnet50, Densenet161) and their sensitivity to changes in object and configuration information over the course of scene processing. Despite differences among the four CNN architectures, across all CNNs, we observed a common pattern in the CNN's response to object identity and configuration changes. Each CNN demonstrated greater sensitivity to configuration changes in early stages of processing and stronger sensitivity to object identity changes in later stages. This pattern persists regardless of the spatial structure present in the image background, the accuracy of the CNN in classifying the scene, and even the task used to train the CNN. Importantly, CNNs' sensitivity to a configuration change is not the same as their sensitivity to any type of position change, such as that induced by a uniform translation of the objects without a configuration change. These results provide one of the first documentations of how object identity and configuration information are weighted in CNNs during scene processing.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Automatic recognition of stutters (ARS) from speech recordings can facilitate objective assessment and intervention for people who stutter. However, the performance of ARS systems may depend on how ...the speech data are segmented and labelled for training and testing. This study compared two segmentation methods: event-based, which delimits speech segments by their fluency status, and interval-based, which uses fixed-length segments regardless of fluency.
Machine learning models were trained and evaluated on interval-based and event-based stuttered speech corpora. The models used acoustic and linguistic features extracted from the speech signal and the transcriptions generated by a state-of-the-art automatic speech recognition system.
The results showed that event-based segmentation led to better ARS performance than interval-based segmentation, as measured by the area under the curve (AUC) of the receiver operating characteristic. The results suggest differences in the quality and quantity of the data because of segmentation method. The inclusion of linguistic features improved the detection of whole-word repetitions, but not other types of stutters.
The findings suggest that event-based segmentation is more suitable for ARS than interval-based segmentation, as it preserves the exact boundaries and types of stutters. The linguistic features provide useful information for separating supra-lexical disfluencies from fluent speech but may not capture the acoustic characteristics of stutters. Future work should explore more robust and diverse features, as well as larger and more representative datasets, for developing effective ARS systems.
Wide pulse pressure: A clinical review Tang, Kevin S.; Medeiros, Edward D.; Shah, Ankur D.
The journal of clinical hypertension (Greenwich, Conn.),
November 2020, Letnik:
22, Številka:
11
Journal Article
Recenzirano
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Pulse pressure naturally increases over time as individuals’ age due to arteriosclerosis and diffuse vascular stiffening. However, the differential for widened pulse pressure is broad and includes ...causes of hyperdynamic circulation and high‐output heart failure, such as aortic regurgitation and hyperthyroidism. In the absence of an underlying cause, wide pulse pressure is a sign of deteriorating cardiovascular health and carries increased risk for mortality, disease progression, and adverse clinical outcomes in chronic diseases including cardiovascular disease and chronic kidney disease. Current emphasis of antihypertensive treatment on systolic and diastolic blood pressure does not always address pulse pressure, thus subjecting many patients to an independent risk factor for poor outcomes. Pulse pressure control is more successfully achieved with thiazide diuretics and long‐acting nitrates when compared to other antihypertensive agents, but further research is needed to quantify the additional benefits of pulse pressure control over conventional blood pressure therapy. This case review provides an overview of the pathogenesis, pathologic causes, and treatment of widened pulse pressure and evaluates current evidence for pulse pressure as a predictor of clinical outcomes.
The problem of distributed learning and channel access is considered in a cognitive network with multiple secondary users. The availability statistics of the channels are initially unknown to the ...secondary users and are estimated using sensing decisions. There is no explicit information exchange or prior agreement among the secondary users and sensing and access decisions are undertaken by them in a completely distributed manner. We propose policies for distributed learning and access which achieve order-optimal cognitive system throughput (number of successful secondary transmissions) under self play, i.e., when implemented at all the secondary users. Equivalently, our policies minimize the sum regret in distributed learning and access, which is the loss in secondary throughput due to learning and distributed access. For the scenario when the number of secondary users is known to the policy, we prove that the total regret is logarithmic in the number of transmission slots. This policy achieves order-optimal regret based on a logarithmic lower bound for regret under any uniformly-good learning and access policy. We then consider the case when the number of secondary users is fixed but unknown, and is estimated at each user through feedback. We propose a policy whose sum regret grows only slightly faster than logarithmic in the number of transmission slots.
Artificial language learning research has become a popular tool to investigate universal mechanisms in language learning. However, often it is unclear whether the found effects are due to learning, ...or due to artefacts of the native language or the artificial language, and whether findings in only one language will generalise to speakers of other languages. The present study offers a new approach to model the influence of both the L1 and the target artificial language on language learning. The idea is to control for linguistic factors of the artificial and the native language by incorporating measures of wordlikeness into the statistical analysis as covariates. To demonstrate the approach, we extend Linzen and Gallagher (2017)’s study on consonant identity pattern to evaluate whether speakers of German and Mandarin rapidly learn the pattern when influences of L1 and the artificial language are accounted for by incorporating measures assessed by analogical and discriminative learning models over the L1 and artificial lexicon. Results show that nonwords are more likely to be accepted as grammatical if they are more similar to the trained artificial lexicon and more different from the L1 and, crucially, the identity effect is still present. The proposed approach is helpful for designing cross-linguistic studies.
This study investigates the Turkish partial reduplication phenomenon, in which the reduplicant is derived by prefixing C1VC2 syllable, where C1V are identical to the word-initial CV of the base and ...the C2endsin one of the four linking consonants: -p, -m, -s, -r. This study re-examines the factors conditioning the choice of the linking consonant, by focusing the nature of the (dis)similarity (feature specificity) and the proximity (locality) between the consonants in the base and the linking consonant, using an acceptability rating task with over 200 participants and a diverse set of stimuli in terms of length and word shapes. Results indicate a gradient identity avoidance effect that extends over all consonants in the base. Crucially, the effect of all consonants is not uniform, with the strength of the effect decreasing further into the base. The study also uncovers an elusive interplay between the distance-based decay effect and the syllable position effect, both of which turn out to play a role in these non-categorical patterns with multiple features. Furthermore, results indicate that identity avoidance operates over both individual features as well as whole segments. Overall, the study argues that locality-sensitive feature-specific identity avoidance constraints are part of the grammar.
The perciform group Labroidei includes approximately 2600 species and comprises some of the most diverse and successful lineages of teleost fishes. Composed of four major clades, Cichlidae, Labridae ...(wrasses, parrotfishes, and weed whitings), Pomacentridae (damselfishes), and Embiotocidae (surfperches); labroids have been an icon for studies of biodiversity, adaptive radiation, and sexual selection. The success and diversification of labroids have been largely attributed to the presence of a major innovation in the pharyngeal jaw apparatus, pharyngognathy, which is hypothesized to increase feeding capacity and versatility. We present results of large-scale phylogenetic analyses and a survey of pharyngeal jaw functional morphology that allow us to examine the evolution of pharyngognathy in a historical context. Phylogenetic analyses were based on a sample of 188 acanthomorph (spiny-rayed fish) species, primarily percomorphs (perch-like fishes), and DNA sequence data collected from 10 nuclear loci that have been previously used to resolve higher level ray-finned fish relationships. Phylogenies inferred from this dataset using maximum likelihood, Bayesian, and species tree analyses indicate polyphyly of the traditional Labroidei and clearly separate Labridae from the remainder of the traditional labroid lineages (Cichlidae, Embiotocidae, and Pomacentridae). These three "chromide" families grouped within a newly discovered clade of 40 families and more than 4800 species (> 27% of percomorphs and > 16% of all ray-finned fishes), which we name Ovalentaria for its characteristic demersal, adhesive eggs with chorionic filaments. This fantastically diverse clade includes some of the most species-rich lineages of marine and freshwater fishes, including all representatives of the Cichlidae, Embiotocidae, Pomacentridae, Ambassidae, Gobiesocidae, Grammatidae, Mugilidae, Opistognathidae, Pholidichthyidae, Plesiopidae (including Notograptus), Polycentridae, Pseudochromidae, Atherinomorpha, and Blennioidei. Beyond the discovery of Ovalentaria, this study provides a surprising, but well-supported, hypothesis for a convictblenny (Pholidichthys) sister group to the charismatic cichlids and new insights into the evolution of pharyngognathy. Bayesian stochastic mapping ancestral state reconstructions indicate that pharyngognathy has evolved at least six times in percomorphs, including four separate origins in members of the former Labroidei, one origin in the Centrogenyidae, and one origin within Beloniformes. Our analyses indicate that all pharyngognathous fishes have a mechanically efficient biting mechanism enabled by the muscular sling and a single lower jaw element. However, a major distinction exists between Labridae, which lacks the widespread, generalized percomorph pharyngeal biting mechanism, and all other pharyngognathous clades, which possess this generalized biting mechanism in addition to pharyngognathy. Our results reveal a remarkable history of pharyngognathy: far from a single origin, it appears to have evolved at least six times, and its status as a major evolutionary innovation is reinforced by it being a synapomorphy for several independent major radiations, including some of the most species rich and ecologically diverse percomorph clades of coral reef and tropical freshwater fishes, Labridae and Cichlidae.
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Dostopno za:
BFBNIB, DOBA, IZUM, KILJ, NMLJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Over the last half-century, discussions on the exact targets for low-density lipoprotein cholesterol (LDL-C) reduction have evolved towards a more aggressive approach with lower LDL-C targets, ...particularly for high-risk patients with pre-existing atherosclerotic cardiovascular disease (ASCVD). A wealth of cardiovascular outcome trials have shown the efficacy of statin therapy in general, as well as the incremental impact of high-intensity statin therapy in particular. More recent trials have further demonstrated the impact of non-statin therapies, including ezetimibe, proprotein convertase subtilisin/kexin type 9 inhibitors, and, most recently, bempedoic acid, on reducing ASCVD outcomes. The availability of these and other newer therapies has prompted clinicians to strive for lower LDL-C targets to address residual ASCVD risk after statin therapy. This paper will provide an overview of the historical trends in lipid management and therapeutics and review the current state of evidence for lower LDL-C targets in clinical guidelines and recommendations.
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