According to a very large case series from the Chinese Center for Disease Control and Prevention (72,314 cases, updated through February 11, 2020), more than 80% of COVID-19 cases presented mild ...symptoms 1. ...the standard for detection of SARS-CoV-2 are real-time reverse-transcriptase polymerase-chain-reaction (RT-PCR) assays collected by nasal and oropharyngeal swabs, meaning that virus load in these sites should be high 7. The American Academy of Otolaryngology - Head and Neck Surgery 21, the Confederation of European Otorhinolaryngology - Head & Neck Surgery 22, the British Association of Otorhinolaryngology 23, the French 24 and Italian 25 ENT societies have already published recommendations for the use of PPE during upper airways examinations, endoscopy, or during surgical interventions (e.g. tracheostomy).Declaration of competing interest and source of funding The authors have nothing to declare.
In this article, tunable integrated filter/antennas are demonstrated with two coupling configurations that provide design control of the bandwidth performance over the tuning range. The first is a ...single-layer third-order tunable filter/antenna with an increasing fractional bandwidth (FBW). The measured device has a frequency tuning range from 1.62 to 2.08 GHz, an FBW increasing from 3.0% to 4.8%, and a gain increasing from -7.3 to 3.6 dBi. The second is a double-layer vertically integrated third-order tunable filter/antenna that provides a constant absolute bandwidth over the tuning range. This design accounts for the frequency-dependent behavior of the antenna radiation Q. The constant absolute bandwidth device is tunable from 1.65 to 1.90 GHz, has a maximum bandwidth variation of 45.3 ±7.4 MHz over the tuning range, and exhibits a gain from -6.1 to 4.3 dBi.
Relational approaches bear a distinct added value for the study of the EU and international negotiations. In this research note we advocate for the combination of social network analysis with ...practice theory to better capture social relational forms of state power. We introduce the concepts of position and process power to develop an analytical framework that conceptualizes negotiations as dynamic interactions between the two. We contend that negotiation outcomes rest on a country's ability to shape subsequent network configurations based on its initial network position and its competent performance of practices. Among other things, our framework offers a nuanced understanding of the formation and role of coalition groupings as well as the forms of social relational power that can emerge among states. As we argue, states can both 'be' (due to exogenous and pre-existing factors) and 'become' powerful (thanks to the social dynamics unique to each negotiation).
Here, an updated and improved version of the effective interaction based on the Argonne-Urbana nuclear Hamiltonian, derived using the formalism of correlated basis functions and the cluster expansion ...technique, is employed to obtain a number of properties of cold nuclear matter at arbitrary neutron excess within the formalism of many-body perturbation theory. The numerical results, including the ground-state energy per nucleon, the symmetry energy, the pressure, the compressibility, and the single-particle spectrum, are discussed in the context of the available empirical information, obtained from measured nuclear properties and heavy-ion collisions.
Euro‐Mediterranean Centre on Climate Change coupled climate model (CMCC‐CM2) represents the new family of the global coupled climate models developed and used at CMCC. It is based on the atmospheric, ...land and sea ice components from the Community Earth System Model coupled with the global ocean model Nucleus for European Modeling of the Ocean. This study documents the model components, the coupling strategy, particularly for the oceanic, atmospheric, and sea ice components, and the overall model ability in reproducing the observed mean climate and main patterns of interannual variability. As a first step toward a more comprehensive, process‐oriented, validation of the model, this work analyzes a 200‐year simulation performed under constant forcing corresponding to present‐day climate conditions. In terms of mean climate, the model is able to realistically reproduce the main patterns of temperature, precipitation, and winds. Specifically, we report improvements in the representation of the sea surface temperature with respect to the previous version of the model. In terms of mean atmospheric circulation features, we notice a realistic simulation of upper tropospheric winds and midtroposphere geopotential eddies. The oceanic heat transport and the Atlantic meridional overturning circulation satisfactorily compare with present‐day observations and estimates from global ocean reanalyses. The sea ice patterns and associated seasonal variations are realistically reproduced in both hemispheres, with a better skill in winter. Main weaknesses of the simulated climate are related with the precipitation patterns, specifically in the tropical regions with large dry biases over the Amazon basin. Similarly, the seasonal precipitation associated with the monsoons, mostly over Asia, is weaker than observed. The main patterns of interannual variability in terms of dominant empirical orthogonal functions are faithfully reproduced, mostly in the Northern Hemisphere winter. In the tropics the main teleconnection patterns associated with El Niño–Southern Oscillation and with the Indian Ocean Dipole are also in good agreement with observations.
Key Points
New CMCC climate model built coupling atmosphere and land components of NCAR model with NEMO ocean model
Realistic representation of mean climate and main patterns of variability, mostly for the Northern Hemisphere winter
Improvements in some aspects of the SST pattern with respect to a previous version of CMCC model
This article introduces the second generation CMCC Earth System Model (CMCC‐ESM2) that extends a number of marine and terrestrial biogeochemical processes with respect to its CMIP5 predecessor. In ...particular, land biogeochemistry was extended to a wider set of carbon pools and plant functional types, along with a prognostic representation of the nitrogen cycle. The marine ecosystem representation was reshaped toward an intermediate complexity of lower trophic level interactions, including an interactive benthic compartment and a new formulation of heterotrophic bacterial population. Details are provided on the model setup and implementation for the different experiments performed as contribution to the sixth phase of the Coupled Model Intercomparison Project. CMCC‐ESM2 shows an equilibrium climate sensitivity of 3.57°C and a transient climate response of 1.97°C which are close to the CMIP5 and CMIP6 multi‐model averages. The evaluation of the coupled climate‐carbon response in the historical period against available observational datasets show a consistent representation of both physical and biogeochemical quantities. However, the land carbon sink is found to be weaker than the current global carbon estimates and the simulated marine primary production is slightly below the satellite‐based average over recent decades. Future projections coherently show a prominent global warming over the northern hemisphere with intensified precipitations at high latitudes. The expected ranges of variability for oceanic pH and oxygen, as well as land carbon and nitrogen soil storage, compare favorably with those assessed from other CMIP6 models.
Plain Language Summary
Earth System Models integrate our knowledge on the underlying physical and biogeochemical mechanisms that drive or influence the global climate and the biosphere over the land and in the ocean. These models are used to provide realistic estimates of climate variability and its response to perturbations in the chemical constituents of the atmosphere and modifications of the terrestrial surface. This work describes the science at the base of the second generation Earth System Model developed at the Euro‐Mediterranean Centre on Climate Change and the major results obtained from the simulation of historical (from the pre‐industrial period until present) and different future scenarios up to 2100 in the context of the sixth Coupled Model Intercomparison Project. The model provides a solid representation of the present‐day physical climate and biosphere dynamics in comparison to available observations and data reconstruction of the recent past. The projected global warming signal and carbon accumulation within terrestrial and oceanic systems under future climate scenarios are comparable to the findings of other models involved in the sixth intercomparison project.
Key Points
This work introduces the second generation CMCC Earth System Model (CMCC‐ESM2) and its configuration for CMIP6
Estimated climate sensitivity and carbon‐climate feedbacks are similar to average of CMIP5 and locate in the lower end of CMIP6
Both climate and biogeochemical dynamics are assessed through the comparison with observations and previous literature findings
The complexity of many-body quantum wave functions is a central aspect of several fields of physics and chemistry where nonperturbative interactions are prominent. Artificial neural networks (ANNs) ...have proven to be a flexible tool to approximate quantum many-body states in condensed matter and chemistry problems. In this work we introduce a neural-network quantum state ansatz to model the ground-state wave function of light nuclei, and approximately solve the nuclear many-body Schrödinger equation. Using efficient stochastic sampling and optimization schemes, our approach extends pioneering applications of ANNs in the field, which present exponentially scaling algorithmic complexity. We compute the binding energies and point-nucleon densities of A ≤ 4 nuclei as emerging from a leading-order pionless effective field theory Hamiltonian. We successfully benchmark the ANN wave function against more conventional parametrizations based on two- and three-body Jastrow functions, and virtually exact Green's function Monte Carlo results.
Abstract Introduction Endodontic repair materials such as mineral trioxide aggregate (MTA) are used for various endodontic procedures. An alternative material to MTA with purportedly improved ...handling properties is EndoSequence Root Repair Material, which is available as premixed putty (ESP) or syringeable paste (ESS) and is described as possessing antibacterial activity during its setting reaction due to its highly alkaline pH. The aim of this in vitro study was to determine whether ESP and ESS possess antibacterial properties against a collection of Enterococcus faecalis strains recovered from root canal infections. The hypotheses tested were that (1) ESP and ESS possess antibacterial activity during their setting reaction, (2) there is no difference between ESP, ESS, and MTA in antibacterial activity, and (3) E. faecalis strains isolated from root canals differ in susceptibility to the materials. Methods The direct contact test was used. ESP, ESS, and white MTA were preincubated at 37°C in >95% humidity for 30 minutes and 24 hours before 1-hour direct contact exposure to E. faecalis strains (n = 10). Absence of antibacterial carryover effect from the materials to the bacterial cultures was confirmed. Log10 viable counts were compared by using analysis of variance with significance level at P ≤ .05. Results Combining data for all strains, the mean (± standard deviation) log10 viable counts for ESP (4.55 ± 0.85), ESS (4.5 ± 0.95), and MTA (4.12 ± 1.26) were significantly lower than for untreated controls (7.40 ± 0.33) ( P < .0001). The reduction in viable counts ranged from 1.86 ± 0.24 to 4.78 ± 0.42, with no statistically significant differences between the materials or preincubation periods. One strain was significantly more susceptible than 4 other strains. Conclusions ESP, ESS, and MTA had similar antibacterial efficacy against clinical strains of E. faecalis . Clinical strains varied in their susceptibility to the root repair materials.
The onset of hyperons in the core of neutron stars and the consequent softening of the equation of state have been questioned for a long time. Controversial theoretical predictions and recent ...astrophysical observations of neutron stars are the grounds for the so-called hyperon puzzle. We calculate the equation of state and the neutron star mass-radius relation of an infinite systems of neutrons and Λ particles by using the auxiliary field diffusion Monte Carlo algorithm. We find that the three-body hyperon-nucleon interaction plays a fundamental role in the softening of the equation of state and for the consequent reduction of the predicted maximum mass. We have considered two different models of three-body force that successfully describe the binding energy of medium mass hypernuclei. Our results indicate that they give dramatically different results on the maximum mass of neutron stars, not necessarily incompatible with the recent observation of very massive neutron stars. We conclude that stronger constraints on the hyperon-neutron force are necessary in order to properly assess the role of hyperons in neutron stars.
Young children are prolific question-askers. The growing ubiquity of voice interfaces (e.g., Apple's Siri, Amazon's Alexa), as well as the availability of voice input in search fields, now make it ...possible for children to ask questions via Internet search when they are able to speak clearly, but before they have learned to read and write, typically between 3 and 6 years of age. The prevalence of
makes it important to understand children's changing conceptions of digital devices as a source of information and the role of technology-mediated question-asking in development. While limited research has focused on young children's use of voice interfaces, reviewing two related bodies of literature sheds light on how this use might unfold. This paper brings together studies of how children look for information, and of how they perceive and understand the informational and social roles of technology, drawing on human-computer interaction research. We conclude by highlighting lines of questioning for future work on younger children's interaction through voice search.
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