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Computational units in artificial neural networks compute a linear combination of their inputs, and then apply a nonlinear filter, often a ReLU shifted by some bias, and if the inputs come themselves from other units, they were already filtered with their own biases. In a layer, multiple units share the same inputs, and each input was filtered with a unique bias, resulting in output values being based on shared input biases rather than individual optimal ones. To mitigate this issue, we introduce DAC, a new computational unit based on preactivation and multiple biases, where input signals undergo independent nonlinear filtering before the linear combination. We provide a Keras implementation and report its computational efficiency. We test DAC convolutions in ResNet architectures on CIFAR-10, CIFAR-100, Imagenette, and Imagewoof, and achieve performance improvements of up to 1.73%. We exhibit examples where DAC is more efficient than its standard counterpart as a function approximator, and we prove a universal representation theorem., Major rewriting. Superseeds v1

The effect of transport noise on a 2D fluid may depend on the space-scale of the noise. We investigate numerically the dissipation properties of very small-scale transport noise. As a test problem we consider the Kelvin-Helmholtz instability and we compare the inviscid case, the viscous one, both without noise, and the inviscid case perturbed by transport noise. We observe a partial similarity with the viscous case, namely a delay of the instability., Comment: 22 pages, 22 figures

In the present article we introduce a variant of Smoluchowski's coagulation equation with both position and velocity variables taking a kinetic viewpoint arising as the scaling limit of a system of second-order (microscopic) coagulating particles. We focus on the rigorous study of the PDE system in the spatially-homogeneous case proving existence and uniqueness under different initial conditions in suitable weighted space, investigating also the regularity of such solutions., Comment: 38 pages, single column

This paper analyses the effect of the COVID-19 pandemic on household disposable income and household demand in the European Union (EU), making use of the EU microsimulation model EUROMOD and nowcasting techniques. We show evidence of heterogeneity in the impact of the COVID-19 pandemic on the labour markets in EU Member States, with some countries hit substantially harder than others. Most EU Member States experience a large drop in market incomes in 2020, with poorer households hit the hardest. Tax-benefit systems cushioned significantly the transmission of the shock to the disposable income and the household demand, with monetary compensation schemes playing a major role. Additionally, we show that monetary compensation schemes prevent a significant share of households from becoming liquidity constrained during the pandemic.

To review the dynamic analytical elements used in the functional assessment of the stomatognathic system, summarize the available scientific evidence, and consider interrelations with body posture and cognition. A thorough literature search was conducted using PubMed, the Cochrane Library database, and Google Scholar. Peer-reviewed articles and literature reviews provided up-to-date information addressing three topics: (a) the available knowledge and recent evidence on the relationship between the morphologic aspects of dental/craniofacial anatomy and oral function/dysfunction, (b) mandibular dynamics, considering mobility, functional activity, and existing methodologies of analysis, and (c) a possible correlation between the stomatognathic system, body posture, and cognition. Modern dentistry may be regarded as a human adaptation strategy, helping to conserve healthy teeth for much longer without risking overall health. It is futile to treat patients using a mechanistic, sectorial approach that misrepresents patient behavior and requests, just as it is to affirm the absence of any structure-function relationships. However, it is also evident that there is a lack of general consensus on the precise functional assessment of the stomatognathic system, mostly due to the methodologic heterogeneity employed and the high risk of bias. Despite the abundant evidence produced with the aim of providing solid arguments to define dynamic models of functional assessment of the stomatognathic system, it is yet to become highly empirical, based as it is on operator experience in daily clinical practice. Further efforts from the scientific and clinical community, with the help of progress in technology, remain should this gap be filled and should substantial data on differences between pathologic and physiologic dynamic models of function be provided. Dentistry needs to employ - on a larger scale - objective, dynamic methods of analysis for the functional evaluation of the stomatognathic system, embracing concepts of "personalized medicine" and "interprofessional collaborations."

Analysis of the relationship between taxes and self-employment should account for the interplay between responses in self-employment and wage employment. To this end, we estimate a two-state multi-spell duration model which accounts for both observed and unobserved heterogeneity using a large longitudinal administrative dataset for Norway for 1993 to 2011. Our findings confirm theoretical predictions, and are robust to various changes to definitions and sample selections. A policy experiment simulating a flatter tax schedule in the year 2000 is found to encourage self-employment, delivering a net increase of predicted inflow into self-employment from 2.8% to 5.3%.

Turbulence in growth of rain droplets and rain formation is studied under an approximating particle system representing aggregation at the level of individuals, depending on their volume and distance in space, of the Smoluchowski Coagulation equation. A random field is introduced to model the air flow interaction with the particles and it is proved that the empirical density of the individual converges to solutions of limiting equation under different setting for the random field of interaction. A brief numerical study for the continuous density is proposed using the particles approach, to analyze how noise can arise in such system and the effectiveness on rain formation., Comment: 25 pages, 13 figures

Infection spread among individuals is modelled with a continuous time Markov chain, in which subject interactions depend on their distance in space. The well known SIR model and non local variants of the latter are then obtained as large scale limits of the individual based model in two different scaling regimes of the interaction., 22 pages

This paper contributes to the literature on the distributional properties of VAT analysing who bears higher VAT payments between native and migrant household in France, Germany and Spain. The question is of interest both from a distributional and fiscal perspective, fitting the ongoing debate of the net fiscal impact of immigration. Using data from the 2010 EU HBS and a simple VAT calculator we show the existence of gaps in effective VAT rates between native and migrant households in France and in Spain, while no significant gap is observed in Germany. Our results also confirm the existing evidence on the regressivity of VAT with respect to income. These findings suggest that the fairness consequences of VAT reforms should be carefully assessed and advocate for the importance of considering indirect taxation when assessing the fiscal cost of migration.

The Norwegian dual income tax system gave incentives for business owners to incorporate and take advantage of the lower tax on capital income. The tax reform of 2006, which was designed to eliminate these incentives, is used to discuss effects of taxation on the choice of organisational form. The interplay between the tax reform and the pre-existing system of geographically differentiated payroll tax rates generates heterogeneity in the tax treatment, which is exploited in a difference-in-differences empirical strategy. Estimation results based on a large administrative dataset suggest that organisational choice is influenced by taxes: a 1 percentage point reduction in the payroll tax results in 1 percent increase in incorporation rate.

A Smoluchowski type model of coagulation in a turbulent fluid is given, first expressed by means of a stochastic model, then in a suitable scaling limit as a deterministic model with enhanced diffusion in the velocity component. A precise link between mean intensity of the turbulent velocity field and coagulation enhancement is obtained by numerical simulations, and a formula for the mean velocity difference, in agreement with the gas-kinetic model, is proved by a new method., Comment: 18 pages, double column, 20 figures. Added appendix, more details on presented methods. Added derived formulas on kernel, added new notations

Before the end of the Last Glacial Maximum (LGM, ∼16.5 ka ago) set in motion major shifts in human culture and population structure, a consistent change in lithic technology, material culture, settlement pattern, and adaptive strategies is recorded in Southern Europe at ∼18–17 ka ago. In this time frame, the landscape of Northeastern Italy changed considerably, and the retreat of glaciers allowed hunter-gatherers to gradually recolonize the Alps. Change within this renewed cultural frame (i.e., during the Late Epigravettian phase) is currently associated with migrations favored by warmer climate linked to the Bølling-Allerød onset (14.7 ka ago), which replaced earlier genetic lineages with ancestry found in an individual who lived ∼14 ka ago at Riparo Villabruna, Italy, and shared among different contexts (Villabruna Cluster). Nevertheless, these dynamics and their chronology are still far from being disentangled due to fragmentary evidence for long-distance interactions across Europe. Here, we generate new genomic data from a human mandible uncovered at Riparo Tagliente (Veneto, Italy), which we directly dated to 16,980–16,510 cal BP (2σ). This individual, affected by focal osseous dysplasia, is genetically affine to the Villabruna Cluster. Our results therefore backdate by at least 3 ka the diffusion in Southern Europe of a genetic component linked to Balkan/Anatolian refugia, previously believed to have spread during the later Bølling/Allerød event. In light of the new genetic evidence, this population replacement chronologically coincides with the very emergence of major cultural transitions in Southern and Western Europe., The research was supported by the European Union through the European Research Council under the European Union’s Horizon 2020 Research and Innovation Programme (grant agreement no. 724046 – Success awarded to S.B., http://www.erc-success.eu; grant agreement no. 803147 Resolution awarded to S.T., https://site.unibo.it/resolution-erc/en) as well as through the European Regional Development Fund (project no. 2014–2020.4.01.16–0030 to C.L.S. and T.S.) and projects no. 2014-2020.4.01.16-0024 and MOBTT53 (L.P.), by the Estonian Research Council personal research grant (PRG243; C.L.S.), and by UniPd PRID 2019 (L.P.).

Objectives Exact symmetry and perfect balance between opposite jaw halves, as well as between antagonistic teeth, is not frequently observed in natural masticatory systems. Research results show that asymmetry in our body, skull, and jaws is often related to genetic, epigenetic, environmental and individual ontogenetic factors. Our study aims to provide evidence for a significant link between masticatory asymmetry and occlusal contact between antagonist teeth by testing the hypothesis that tooth inclination is one of the mechanisms driving distribution of wear in masticatory phases in addition to dietary and cultural habits. Materials and Methods The present work investigates the relationship between dental macrowear patterns and tooth inclinations on a sample of complete maxillary and mandibular 3D models of dental arches from 19 young and adult Yuendumu Aboriginal individuals. The analysis was carried out on first molars (M1) from all quadrants. Occlusal Fingerprint Analysis was used for the quantification of macrowear patterns, and 2D cross‐sectional geometric analysis was carried out to investigate asymmetry in dental arches. Results The asymmetry is highly variable on both arches, and it is associated with differences in the inclination of upper M1 crowns. Each molar has variable inclination (buccal/lingual) which influence tooth to tooth contact, producing greater or lesser variation in wear pattern. Interindividual variability of morphological variation of the occlusal relationship has to be considered in macrowear analysis. Discussion Our results suggest that overall asymmetry in the masticatory apparatus in modern humans affects occlusal contact areas between antagonist teeth influencing macrowear and chewing efficiency during ontogeny.

Among novel technologies for producing electricity from renewable resources, a new class of wind energy converters has been conceived under the name of Airborne Wind Energy Systems (AWESs). This new generation of systems employs flying tethered wings or aircraft in order to reach winds blowing at atmosphere layers that are inaccessible by traditional wind turbines. Research on AWESs started in the mid seventies, with a rapid acceleration in the last decade. A number of systems based on radically different concepts have been analyzed and tested. Several prototypes have been developed all over the world and the results from early experiments are becoming available. This paper provides a review of the different technologies that have been conceived to harvest the energy of high-altitude winds, specifically including prototypes developed by universities and companies. A classification of such systems is proposed on the basis of their general layout and architecture. The focus is set on the hardware architecture of systems that have been demonstrated and tested in real scenarios. Promising solutions that are likely to be implemented in the close future are also considered.