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Online tree expansion could help solve the problem of scalability in Bayesian phylogenetics

Bayesian phylogenetics is now facing a critical point. Over the last 20 years, Bayesian methods have reshaped phylogenetic inference and gained widespread popularity due to their high accuracy, the ability to quantify the uncer‑ tainty of inferences and the possibility of accommodating multiple aspects of evolutionary processes in the models that are used. Unfortunately, Bayesian methods are compu

Infectivity of exhaled SARS-CoV-2 aerosols is sufficient to transmit covid-19 within minutes

Exhaled SARS-CoV-2-containing aerosols contributed significantly to the rapid and vast spread of covid-19. However, quantitative experimental data on the infectivity of such aerosols is missing. Here, we quantified emission rates of infectious viruses in exhaled aerosol from individuals within their first days after symptom onset from covid-19. Six aerosol samples from three individuals were cultu

Contortatallens liv i Sverige ur ett kulturellt perspektiv

Sedan 1920-talet har det funnits planer på att använda contortatall i svenskt skogsbruk men först kring 1970omsattes de till storskaliga planteringar i norra Sverige.Sedan 1970-talet har contortatallen debatterats och knutits till olika sammanhang och skilda värderingsregimer.Återkommande har forskare samt företrädare för skogsnäringen och olika miljörörelser försökt att avgränsacontortans betydel

Null-Space Compliance Variation for Safe Human-Robot Collaboration in Redundant Manipulators using Safety Control Barrier Functions

In this paper, Safety Control Barrier Functions (SCBFs) were used to adjust the null-space compliant behavior of a redundant robot to improve safety in Human–Robot Collaboration (HRC) without modifying the robot behavior with respect to its main Cartesian task. A Lyapunov function was included in an energy storage formulation compatible with strict passivity to provide global asymptotic stability

The High–Low Arctic boundary : How is it determined and where is it located?

Geobotanical subdivision of landcover is a baseline for many studies. The High–Low Arctic boundary is considered to be of fundamental natural importance. The wide application of different delimitation schemes in various ecological studies and climatic scenarios raises the following questions: (i) What are the common criteria to define the High and Low Arctic? (ii) Could human impact significantly

The role of loudness in vocal intimidation

Across many species, a major function of vocal communication is to convey formidability, with low voice frequencies traditionally considered the main vehicle for projecting large size and aggression. Vocal loudness is often ignored, yet it might explain some puzzling exceptions to this frequency code. Here we demonstrate, through acoustic analyses of over 3,000 human vocalizations and four percept

Photoelectron Signatures of Nonperturbative Dynamics in Resonant Two-photon Ionization of Helium

When an atom is driven by a laser field with a photon energy that is nearly resonant with an atomic transition, it can undergo periodic population transfers between the ground and excited state, known as Rabi oscillations [1,2]. The aim of this work is to study photoionization from atoms for parameters accessible to a free-electron laser (FEL) [3]. Using time dependent perturbation theory to model

Current capabilities of the imaging endstation at the NanoMAX beamline

The new imaging endstation of the NanoMAX beamline is being designed to complement the already existing diffraction endstation: measurements with smaller beams at lower photons energies, with higher stability, in vacuum and with sample cooling at the measurement position, optimized for X-ray fluorescence mapping and ptychographic imaging in two and three spatial dimensions. This comes at the cost

Isonicotinate-Zn(ii)/Cd(ii) bridged dicobaloximes : synthesis, characterization and electrocatalytic proton reduction studies

Herein, we present the synthesis of two new dicobaloxime complexes, [{ClCo(dmgH)2(4-PyCOO)}2Zn(DMF)2] (1) and [{ClCo(dmgH)2(4-PyCOO)}2Cd(H2O)3(DMF)].4H2O (2) bridged by isonicotinate-Zn(ii) and Cd(ii) moieties. These complexes were synthesized upon reaction of a monomeric chlorocobaloxime [ClCo(dmgH)2(4-PyCOOH)] with Zn(NO3)2·6H2O and Cd(OAc)2·2H2O in a methanol/DMF solvent mixture. Both complexes

Unraveling Rabi dynamics with a seeded FEL at XUV wavelength

Rabi oscillations, a prominent feature of coherent light-matter interaction arise when a two-level system interacts periodically with an external electromagnetic field [1]. Despite being a cornerstone in quantum physics, they are usually studied in the long-wavelength region, ranging from mid-infrared to visible. Here, we demonstrate that intense femtosecond extreme-ultraviolet (XUV) pulses from F

Local structural mechanism for enhanced energy storage properties in heterovalent doped NaNbO3 ceramics

In recent years, there is a growing interest for new lead-free oxides with reversible antiferroelectric (AFE)-ferroelectric (FE) phase transition for high-power energy-storage applications. NaNbO3-based ceramics are particularly attractive due to their easy synthesis and cost-effectiveness. In order to stabilize reversible AFE-FE phase transition, NaNbO3 is doped with a combination of heterovalent

Characterizing Ultrashort Laser Pulses With a Time-Dependent Polarization State Using the D-Scan Technique

The main idea behind the presented work is to extend the dispersion scan (d-scan) technique to measuring the time-dependent polarization state of ultrashort laser pulses. For demonstration, a rapidly varying polarization state, i.e. a polarization gate, was created from ultrashort pulses with a duration of 6 fs using a combination of wave plates. The time-dependent variation of the polarization wa

EXPLOITING AXIAL PRIMARY RADIATION FORCE FOR ACOUSTOFLUIDIC PARTICLE TRAPPING

In the present study, we demonstrate an acoustofluidic trapping technique based on the standing bulk acoustic waves (S-BAW) generated inside a uniquely designed chamber - the 'shaped trap' that enables the particle to experience the axial primary radiation force (A-PRF) along the flow direction as the main trapping force.

Effects of Brain Pathologies on Spatiotemporal Gait Parameters in Patients with Mild Cognitive Impairment

Background: Impaired gait can precede dementia. The associations between gait parameters and brain pathologies are therefore of interest. Objective: To explore how different brain pathologies (i.e., vascular and Alzheimer's) are associated with specific gait parameters from various gait components in persons with mild cognitive impairment (MCI), who have an increased risk of developing dementia. M

Methodological strategies to understand smartphone practices for social connectedness in later life

Digital practices in later life are not yet well understood. Therefore, this paper discusses the framework for a research design project that aims at tracing differences and similarities in how older adults use their smartphones in circumstances in and outside their homes in Spain, the Netherlands, Sweden, and Canada. The research questions of this international research project focus on the exten

Using academic work places to involve older people in the design of digital applications : presentation of a methodological framework to advance co-design in later life

Methods to involve users in design have long been used to create relevant content and increase the accuracy of product development. Demographic trends have raised the issue of the needs and demands of older people, especially with regard to digitization. In contrast to the high number of publications discussing the importance of involving people in the design of their daily life, very few publicat

Of robots and humans : creating user representations in practice

In this study, we explore the constitution of user representations of robots in design practice. Using the results of ethnographic research in two robot laboratories, we show how user representations emerge in and are entangled with design activities. Our study speaks to the growing popularity of and investment in robotics, robots and other forms of artificial intelligence. Scholars in Science and