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In living cells, molecular motors create activity that enhances the diffusion of particles throughout the cytoplasm, and not just ones attached to the motors. We demonstrate initial steps toward creating artificial cells that mimic this phenomenon. Our system consists of active, Pt-coated Janus particles and passive tracers confined to emulsion droplets. We track the motion of both the active particles and passive tracers in a hydrogen peroxide solution, which serves as the fuel to drive the motion. We first show that correcting for bulk translational and rotational motion of the droplets induced by bubble formation is necessary to accurately track the particles. After drift correction, we find that the active particles show enhanced diffusion in the interior of the droplets and are not captured by the droplet interface. At the particle and hydrogen peroxide concentrations we use, we observe little coupling between the active and passive particles. We discuss the possible reasons for lack of coupling and describe ways to improve the system to more effectively mimic cytoplasmic activity. [ABSTRACT FROM AUTHOR]

The systematics of the enigmatic and rather uncommon species of Sea Hayward and Cybdelis Boisduval is assessed through morphological and molecular analyses. The aim of this paper is three‐fold: (i) to ascertain the phylogenetic position of Sea and Cybdelis in Biblidinae; (ii) to determine the evolutionary relationships among species of Sea and Cybdelis; and (iii) to review the taxonomy of Sea and Cybdelis. The result of the molecular analysis recovers Sea sister to Cybdelis, and this clade sister to Eubagina (sensu Lamas,), rendering Epicaliina (sensu Lamas,) paraphyletic. A new tribe, Cybdelini trib.n. is erected to include Sea and Cybdelis; the other genera formerly included in Epicaliina (sensu Lamas,), Eunica Hübner and Sevenia Koçak are assigned to Eunicini trib.rest., and the remaining genera of Biblidinae to other previously recognized tribes, similar to those implicitly proposed by Wahlberg et al. (). The morphological analysis recovers similar results and the following relationships among species of Cybdelis: C. phaesyla (Hübner) (C. boliviana Salvin (C. mnasylus Doubleday (C. petronita Burmeister stat.rest. + C. thrasylla C. Felder & R. Felder stat.rest.))). Sea and Cybdelis are recognized as distinct genera; a new subspecies, S. sophronia jenkinsi Dias, Siewert & Freitas ssp.n., distributed from Venezuela to Bolivia along the Andes eastern foothills, is described; and C. petronita and C. thrasylla are accepted as valid species. Lectotypes for C. boliviana, C. peruviana Staudinger, C. mnasylus, C. thrasylla, C. petronita and C. mnasylus var. meridionalis Hall and a neotype for Vanessa sophronia Godart are designated. Additionally, dichotomous keys and distribution maps to all taxa are provided; male genitalia and hypandria are illustrated for all species; generic characters of the head, labial palpi and legs are illustrated; immature stages of some species also are figured. The published work has been registered on ZooBank: http://zoobank.org/urn:lsid:zoobank.org:pub:D8EBB649‐5E9D‐4218‐B1F1‐7A69DA775FD0. Molecular analysis recovers the validity of the sister genera Sea and Cybdelis, and this clade as sister to Eubagina, rendering Epicaliina (sensu Lamas,) paraphyletic.Cybdelini trib.n. includes Sea and Cybdelis, other genera formerly in Epicaliina (sensu Lamas,) are assigned to Eunicini trib.rest., and the remaining genera to other previously recognized tribes.Morphologic analysis recovers the relationship among species of Sea and Cybdelis; two subspecies of Cybdelis are restituted to species and a new subspecies of Sea sophronia is described. [ABSTRACT FROM AUTHOR]

Quantum two-level systems interacting with the surroundings are ubiquitous in nature. The interaction suppresses quantum coherence and forces the system towards a steady state. Such dissipative processes are captured by the paradigmatic spin-boson model, describing a two-state particle, the “spin”, interacting with an environment formed by harmonic oscillators. A fundamental question to date is to what extent intense coherent driving impacts a strongly dissipative system. Here we investigate experimentally and theoretically a superconducting qubit strongly coupled to an electromagnetic environment and subjected to a coherent drive. This setup realizes the driven Ohmic spin-boson model. We show that the drive reinforces environmental suppression of quantum coherence, and that a coherent-toincoherent transition can be achieved by tuning the drive amplitude. An out-of-equilibrium detailed balance relation is demonstrated. These results advance fundamental understanding of open quantum systems and bear potential for the design of entangled light-matter states. [ABSTRACT FROM AUTHOR]

Summary NanoShaper is a program specifically aiming the construction and analysis of the molecular surface of nanoscopic systems. It uses ray-casting for parallelism and it performs analytical computations whenever possible to maximize robustness and accuracy of the approach. Among the other features, NanoShaper provides volume, surface area, including that of internal cavities, for any considered molecular system. It identifies pockets via a very intuitive definition based on the concept of probe radius, intrinsic to the definition of the solvent excluded surface. We show here that, with a suitable choice of the parameters, the same approach can also permit the visualisation of molecular channels. NanoShaper has now been interfaced with the widely used molecular visualization software VMD, further enriching its already well furnished toolset. Availability and implementation VMD is available at http://www.ks.uiuc.edu/Research/vmd/. NanoShaper, its documentation, tutorials and supporting programs are available at http://concept.iit.it/downloads. Supplementary information Supplementary data are available at Bioinformatics online. [ABSTRACT FROM AUTHOR]

Flow phantoms are widely used in studies associated with Doppler ultrasound measurements, acting as an effective experimental validation system in cardiovascular-related research and in new algorithm/instrumentation development. The development of materials that match the acoustic and mechanical properties of the vascular system is of great interest while designing flow phantoms. Although recipes that meet the flow phantom standard defined by the International Electrotechnical Commission 61685 are already available in the literature, the standard procedure for material preparations and phantom fabrications has not been well established. In this paper, two types of flow phantoms, with and without blood vessel mimic, are described in detail in terms of the material preparation and phantom fabrication. The phantom materials chosen for the two phantoms are from published phantom studies, and their physical properties have been investigated previously. Both the flow phantoms have been scanned by ultrasound scanners and images from different modes are presented. These phantoms may be used in the validation and characterization of Doppler ultrasound measurements in blood vessels with a diameter above 1 mm. [ABSTRACT FROM PUBLISHER]

The breakthrough capacity of optoacoustics for three-dimensional visualization of dynamic events in real time has been recently showcased. Yet, efficient spectral unmixing for functional imaging of entire volumetric regions is significantly challenged by motion artifacts in concurrent acquisitions at multiple wavelengths. Here, we introduce a method for simultaneous acquisition of multispectral volumetric datasets by introducing a microsecond-level delay between excitation laser pulses at different wavelengths. Robust performance is demonstrated by real-time volumetric visualization of functional blood parametrers in human vasculature with a handheld matrix array optoacoustic probe. This approach can avert image artifacts imposed by velocities greater than 2 m/s, thus, does not only facilitate imaging influenced by respiratory, cardiac or other intrinsic fast movements in living tissues, but can achieve artifact-free imaging in the presence of more significant motion, e.g. abrupt displacements during handheld-mode operation in a clinical environment. [ABSTRACT FROM AUTHOR]

Reef fish distributions are patchy in time and space with some coral reef habitats supporting higher densities (i.e., aggregations) of fish than others. Identifying and quantifying fish aggregations (particularly during spawning events) are often top priorities for coastal managers. However, the rapid mapping of these aggregations using conventional survey methods (e.g., non-technical SCUBA diving and remotely operated cameras) are limited by depth, visibility and time. Acoustic sensors (i.e., splitbeam and multibeam echosounders) are not constrained by these same limitations, and were used to concurrently map and quantify the location, density and size of reef fish along with seafloor structure in two, separate locations in the U.S. Virgin Islands. Reef fish aggregations were documented along the shelf edge, an ecologically important ecotone in the region. Fish were grouped into three classes according to body size, and relationships with the benthic seascape were modeled in one area using Boosted Regression Trees. These models were validated in a second area to test their predictive performance in locations where fish have not been mapped. Models predicting the density of large fish (≥29 cm) performed well (i.e., AUC = 0.77). Water depth and standard deviation of depth were the most influential predictors at two spatial scales (100 and 300 m). Models of small (≤11 cm) and medium (12–28 cm) fish performed poorly (i.e., AUC = 0.49 to 0.68) due to the high prevalence (45–79%) of smaller fish in both locations, and the unequal prevalence of smaller fish in the training and validation areas. Integrating acoustic sensors with spatial modeling offers a new and reliable approach to rapidly identify fish aggregations and to predict the density large fish in un-surveyed locations. This integrative approach will help coastal managers to prioritize sites, and focus their limited resources on areas that may be of higher conservation value. [ABSTRACT FROM AUTHOR]

In order to reduce line spectrum of radiation noise from submarine, a type of weak radiation double cylindrical ring stiffened shell was proposed. Mechanical impedance theory was used to analyze mechanism of controlling the modal response amplitude of ring-stiffened cylindrical shell. Radial modal mechanical impedance of the ring was derived by introducing the assumption of inner-motion of cylindrical shell's section. Based on the concepts of impedance mismatch and wave conversion, the model of impedance enhancement rib was built and its isolation performance was analyzed. With the consideration of the brace's strong coupling effect, the brace's wave attenuation was designed. Combining the structures of reinforced impedance rib and wave attenuation brace, the structure-borne sound design of double cylindrical shell was done. Further, the characteristics of vibration and sound radiation were numerical analyzed. The results show that the proposed double cylindrical ring stiffened shell could realize radiation noise line spectrum reduction effectively. The vibration mean square velocity, radiation sound power and sound pressure are depressed greatly. The effect of noise depression and vibration reduction is obvious. [ABSTRACT FROM AUTHOR]

A spine was observed in the hind wings of male coffee berry borers, Hypothenemus hampei (Ferrari) (Coleoptera: Curculionidae: Scolytinae), although it was not present in all males. Females do not exhibit the spine. The function of the spine remains unknown although one possibility is that it might have had a stridulatory role in acoustic communication. [ABSTRACT FROM AUTHOR]