This paper describes sunrise, a parallel, free Monte Carlo code for the calculation of radiation transfer through astronomical dust. sunrise uses an adaptive mesh refinement grid to describe ...arbitrary geometries of emitting and absorbing/scattering media, with spatial dynamical range exceeding 104, and it can efficiently generate images of the emerging radiation at arbitrary points in space. In addition to the monochromatic radiative transfer typically used by Monte Carlo codes, sunrise is capable of propagating a range of wavelengths simultaneously. This 'polychromatic' algorithm gives significant improvements in efficiency and accuracy when spectral features are calculated. sunrise is used to study the effects of dust in hydrodynamic simulations of interacting galaxies, and the procedure for this is described. The code is tested against previously published results.
Abstract
Background
Policymakers advocate extended residence in private homes as people age, rather than relocation to long-term care facilities. Consequently, it is expected that older people living ...in their own homes will be frailer and have more complex health problems over time. Therefore, community care for aging people is becoming increasingly important to facilitate prevention of decline in physical and cognitive abilities and unnecessary hospital admission and transfer to a nursing home. The aim of this study was to examine changes in the characteristic of home care clients and home care provided in five European countries between 2001 and 2014 and to explore whether home care clients who are most in need of care receive the care required.
Methods
This descriptive study used data from two European research projects, Aged in Home Care (AdHOC; 2001–2002) and Identifying best practices for care-dependent elderly by Benchmarking Costs and outcomes of Community Care (IBenC; 2014–2016). In both projects, the InterRAI-Home Care assessment tool was used to assess a random sample of home care clients 65 years and older in five European countries. These data facilitate a comparison of physical and cognitive health and the provided home care between countries and study periods.
Results
In most participating countries, both cognitive (measured on the Cognitive Performance Scale) and functional ability (measured on the Activities of Daily Living Hierarchy scale) of home care clients deteriorated over a 10-year period. Home care provided increased between the studies. Home care clients who scored high on the physical and cognitive scales also received home care for a significantly higher duration than those who scored low.
Conclusion
Older people in several European countries remain living in their own homes despite deteriorating physical and cognitive skills. Home care services to this group have increased. This indicates that the government policy of long-term residence at own home among older people, even in increased frailty, has been realised.
Nanopores enable label-free detection and analysis of single biomolecules. Here, we investigate DNA translocations through a novel type of plasmonic nanopore based on a gold bowtie nanoantenna with a ...solid-state nanopore at the plasmonic hot spot. Plasmonic excitation of the nanopore is found to influence both the sensor signal (nanopore ionic conductance blockade during DNA translocation) and the process that captures DNA into the nanopore, without affecting the duration time of the translocations. Most striking is a strong plasmon-induced enhancement of the rate of DNA translocation events in lithium chloride (LiCl, already 10-fold enhancement at a few mW of laser power). This provides a means to utilize the excellent spatiotemporal resolution of DNA interrogations with nanopores in LiCl buffers, which is known to suffer from low event rates. We propose a mechanism based on plasmon-induced local heating and thermophoresis as explanation of our observations.
Measuring temperature and heat flux is important for regulating any physical, chemical, and biological processes. Traditional thermopiles can provide accurate and stable temperature reading but they ...are based on brittle inorganic materials with low Seebeck coefficient, and are difficult to manufacture over large areas. Recently, polymer electrolytes have been proposed for thermoelectric applications because of their giant ionic Seebeck coefficient, high flexibility and ease of manufacturing. However, the materials reported to date have positive Seebeck coefficients, hampering the design of ultra-sensitive ionic thermopiles. Here we report an "ambipolar" ionic polymer gel with giant negative ionic Seebeck coefficient. The latter can be tuned from negative to positive by adjusting the gel composition. We show that the ion-polymer matrix interaction is crucial to control the sign and magnitude of the ionic Seebeck coefficient. The ambipolar gel can be easily screen printed, enabling large-area device manufacturing at low cost.
With the aim of developing a DNA sequencing methodology, we theoretically examine the feasibility of using nanoplasmonics to control the translocation of a DNA molecule through a solid-state nanopore ...and to read off sequence information using surface-enhanced Raman spectroscopy. Using molecular dynamics simulations, we show that high-intensity optical hot spots produced by a metallic nanostructure can arrest DNA translocation through a solid-state nanopore, thus providing a physical knob for controlling the DNA speed. Switching the plasmonic field on and off can displace the DNA molecule in discrete steps, sequentially exposing neighboring fragments of a DNA molecule to the pore as well as to the plasmonic hot spot. Surface-enhanced Raman scattering from the exposed DNA fragments contains information about their nucleotide composition, possibly allowing the identification of the nucleotide sequence of a DNA molecule transported through the hot spot. The principles of plasmonic nanopore sequencing can be extended to detection of DNA modifications and RNA characterization.
Nanostructures of conventional metals offer manipulation of light at the nanoscale but are largely limited to static behavior due to fixed material properties. To develop the next frontier of dynamic ...nano‐optics and metasurfaces, this study utilizes the redox‐tunable optical properties of conducting polymers, as recently shown to be capable of sustaining plasmons in their most conducting oxidized state. Electrically tunable conducting polymer nano‐optical antennas are presented, using nanodisks of poly(3,4‐ethylenedioxythiophene:sulfate) (PEDOT:Sulf) as a model system. In addition to repeated on/off switching of the polymeric nanoantennas, the concept enables gradual electrical tuning of the nano‐optical response, which was found to be related to the modulation of both density and mobility of the mobile polaronic charge carriers in the polymer. The resonance position of the PEDOT:Sulf nanoantennas can be conveniently controlled by disk size, here reported down to a wavelength of around 1270 nm. The presented concept may be used for electrically tunable metasurfaces, with tunable farfield as well as nearfield. The work thereby opens for applications ranging from tunable flat meta‐optics to adaptable smart windows.
Electrically tunable conducting poly(3,4‐ethylenedioxythiophene:sulfate) polymer nano‐optical antennas are reported. In addition to repeated on/off switching of the polymeric nanoantennas, gradual electrical tuning of their nano‐optical response is demonstrated. This work opens for electrically tunable metasurfaces and takes important steps toward applications ranging from tunable flat metalenses and holograms to adaptable smart windows.
Long DNA molecules can self-entangle into knots. Experimental techniques for observing such DNA knots (primarily gel electrophoresis) are limited to bulk methods and circular molecules below 10 ...kilobase pairs in length. Here, we show that solid-state nanopores can be used to directly observe individual knots in both linear and circular single DNA molecules of arbitrary length. The DNA knots are observed as short spikes in the nanopore current traces of the traversing DNA molecules and their detection is dependent on a sufficiently high measurement resolution, which can be achieved using high-concentration LiCl buffers. We study the percentage of molecules with knots for DNA molecules of up to 166 kilobase pairs in length and find that the knotting occurrence rises with the length of the DNA molecule, consistent with a constant knotting probability per unit length. Our experimental data compare favourably with previous simulation-based predictions for long polymers. From the translocation time of the knot through the nanopore, we estimate that the majority of the DNA knots are tight, with remarkably small sizes below 100 nm. In the case of linear molecules, we also observe that knots are able to slide out on application of high driving forces (voltage).
Drivers of population genetic structure are still poorly understood in marine micro‐organisms. We exploited the North Sea–Baltic Sea transition for investigating the seascape genetics of a marine ...diatom, Skeletonema marinoi. Eight polymorphic microsatellite loci were analysed in 354 individuals from ten locations to analyse population structure of the species along a 1500‐km‐long salinity gradient ranging from 3 to 30 psu. To test for salinity adaptation, salinity reaction norms were determined for sets of strains originating from three different salinity regimes of the gradient. Modelled oceanographic connectivity was compared to directional relative migration by correlation analyses to examine oceanographic drivers. Population genetic analyses showed distinct genetic divergence of a low‐salinity Baltic Sea population and a high‐salinity North Sea population, coinciding with the most evident physical dispersal barrier in the area, the Danish Straits. Baltic Sea populations displayed reduced genetic diversity compared to North Sea populations. Growth optima of low salinity isolates were significantly lower than those of strains from higher native salinities, indicating local salinity adaptation. Although the North Sea–Baltic Sea transition was identified as a barrier to gene flow, migration between Baltic Sea and North Sea populations occurred. However, the presence of differentiated neutral markers on each side of the transition zone suggests that migrants are maladapted. It is concluded that local salinity adaptation, supported by oceanographic connectivity patterns creating an asymmetric migration pattern between the Baltic Sea and the North Sea, determines genetic differentiation patterns in the transition zone.
Recent studies show that spherical motile microorganisms in turbulence subject to gravitational torques gather in down-welling regions of the turbulent flow. By analyzing a statistical model we ...analytically compute how shape affects the dynamics, preferential sampling, and small-scale spatial clustering. We find that oblong organisms may spend more time in up-welling regions of the flow, and that all organisms are biased to regions of positive fluid-velocity gradients in the upward direction. We analyze small-scale spatial clustering and find that oblong particles may either cluster more or less than spherical ones, depending on the strength of the gravitational torques.
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