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In this work we develop a numerical simulation of the spray coating of spinning beverage cans. Though the substrate of the can must be axisymmetric, the coating need not be. We start with an evolution equation, which was derived using scaling arguments and perturbation theory. We then use implicit finite differences and an ADI scheme, with periodic boundary conditions, to efficiently solve the problem numerically. The spray fan is modeled as an expanding ellipse, and we use parameters typical of the coating industry in our simulations. The simulations show that if the can rotates an exact integral number of rotations during the spray process, then the coating layer is almost axisymmetric. But when this cannot be achieved, then three-dimensional effects greatly change the coating dynamics of the thin liquid film and must be included in the analysis.

The coating dynamics of a drying paint film with a yield stress is studied. The liquid is modeled as a binary mixture with one volatile component, solvent, and one nonvolatile component, resin. When the solvent has a different surface tension than the resin, solvent evaporation can lead to the creation of surface tension gradients which can potentially overcome the yield stress and dramatically affect the flow history. Using the lubrication approximations to derive the flux of the liquid film parallel to the substrate, we find that the presence of the yield stress causes several distinct flow regimes. The total flux of each of these regimes is summed, and using the continuity equation we derive an evolution equation giving the height of the free surface as a function of the distance along the substrate and time. The resulting equations are discretized and solved numerically using finite differences. High order derivative is treated implicitly, allowing for large time steps and reducing the computational requirements. We find that the presence of a yield stress greatly affects the leveling behavior of the coating. Critical yield stresses exist that can cause maximal leveling of the coating film.

We detected surface waves from two meteorite impacts on Mars. By measuring group velocity dispersion along the impact-lander path, we obtained a direct constraint on crustal structure away from the InSight lander. The crust north of the equatorial dichotomy had a shear wave velocity of approximately 3.2 kilometers per second in the 5- to 30-kilometer depth range, with little depth variation. This implies a higher crustal density than inferred beneath the lander, suggesting either compositional differences or reduced porosity in the volcanic areas traversed by the surface waves. The lower velocities and the crustal layering observed beneath the landing site down to a 10-kilometer depth are not a global feature. Structural variations revealed by surface waves hold implications for models of the formation and thickness of the martian crust., D.K., S.C., D.G., J.C., C.D., A. K., S.C.S., N.D., and G.Z. were supported by the ETH+ funding scheme (ETH+02 19-1: “Planet Mars”). Marsquake Service operations at ETH Zürich were supported by ETH Research grant ETH-06 17-02. N.C.S. and V.L. were supported by NASA PSP grant no. 80NSSC18K1628. Q.H. and E.B. are funded by NASA grant 80NSSC18K1680. C.B. and J.L. were supported by NASA InSight PSP grant no. 80NSSC18K1679. S.D.K. was supported by NASA InSight PSP grant no. 80NSSC18K1623. P.L., E.B., M.D., H.S., E.S., M.W., Z.X., T.W., M.P., R.F.G. were supported by CNES and the Agence Nationale de la Recherche (ANR-19-CE31-0008-08 MAGIS) for SEIS operation and SEIS Science analysis. A.H., C.C. and W.T.P. were supported by the UKSA under grant nos. ST/R002096/1, ST/ W002523/1 and ST/V00638X/1. Numerical computations of McMC Approach 2 were performed on the S-CAPAD/DANTE platform (IPGP, France) and using the HPC resources of IDRIS under the allocation A0110413017 made by GENCI. A.H. was supported by the UKSA under grant nos. ST/R002096/1 and ST/W002523/1. F.N. was supported by InSight PSP 80NSSC18K1627. I.J.D. was supported by NASA InSight PSP grant no. 80NSSC20K0971. L.V.P. was funded by NASANNN12AA01C with subcontract JPL-1515835. The research was carried out in part by W.B.B., M.G. and M.P.P. at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration (80NM0018D0004)

Background The Public Opinion Survey of Human Attributes–Stuttering/Child (POSHA-S/Child; Weidner & St. Louis, 2014 ) is a standard instrument designed to measure the attitudes of children as young as 3 years of age toward stuttering. With preschool and early elementary school–aged children, the POSHA-S/Child is administered individually and face-to-face by an examiner. Older children who are satisfactory readers could be expected to respond to the instrument online, an increasingly popular mode of administering surveys. Purpose The purpose of this study was to compare administration of the POSHA-S/Child in face-to-face versus online administration. Method Children primarily from 1 elementary school and children from other areas in the region responded to the POSHA-S/Child in either a face-to-face individual setting or online. Three grade levels were included: 3rd grade, 4th grade, and 5th grade. Results POSHA-S/Child ratings for individual items, components, subscores, and the Overall Stuttering Scores from the 2 modes of administration were similar. Conclusion With satisfactory reading abilities, children aged 9 years and older can be administered the POSHA-S/Child online with similar results as face-to-face administration.

This study reports the first high-time-resolution observations of interstellar pickup ions (PUIs) in the outer heliosphere, including the first high-resolution observations of PUIs mediating shocks collected anywhere. These new data were enabled by a clever flight software reprogramming of the Solar Wind Around Pluto (SWAP) instrument on New Horizons to provide ∼30 minutes resolution as compared to the previous ∼24 hr time resolution. This time resolution is sufficient to resolve the shock structures and quantify the particle heating across these shocks. In the ∼10 months of initial data, we observed seven relatively small shocks, including one reverse shock. We find that the PUIs are preferentially compressed and heated across the shocks, indicating compression ratios from ∼1.2–1.8, with little heating for values less than ∼1.5 and progressively more PUI heating for larger compression ratios. In contrast, core solar wind properties did not show consistent changes across the shocks, indicating that these particles (1) participate little in the large-scale fluid-like interactions of the outer heliosphere’s combined solar wind and PUI plasma and (2) cannot be used to characterize PUI-mediated shocks as prior studies sought to do. All six forward shock crossings showed gradual increases in PUI pressure over shock widths of ∼0.05–0.13 au, which is roughly three decades larger than characteristic particle scales such as the PUI gyroradii. The new high-resolution observations and results described here are important for understanding shocks in the outer heliosphere, the termination shock, and more broadly for PUI-mediated shocks across many astrophysical systems.

Purpose Negative or uninformed stuttering attitudes proliferate among the general public, and bourgeoning research has shown that such attitudes might emerge as early as the preschool years. Much remains unknown about young children's stuttering attitudes, and conclusive recommendations to improve attitudes toward stuttering have yet to be advanced. This study sought to determine the effect of a new educational program on improving stuttering attitudes among preschool children using objective measures. Method Thirty-seven preschool children learned about stuttering and sensitive peer interactions by participating in the newly developed Attitude Change and Tolerance program. The program teaches children about human differences with an emphasis on stuttering and how to interact with people who stutter. Children's stuttering attitudes were measured using the Public Opinion Survey of Human Attributes–Stuttering/Child (Weidner & St. Louis, 2014) before and after the program. Results Pre–post comparisons showed statistically significant improvements in children's overall stuttering attitudes. In particular, children demonstrated gains relative to their perceptions of and reactions toward people who stutter. Conclusion This study provides empirical evidence that young children's stuttering attitudes can be improved using the Attitude Change and Tolerance program. In addition, it supports previous research that negative stuttering attitudes emerge as early as preschool.

The Kuiper Belt is a distant region of the outer Solar System. On 1 January 2019, the New Horizons spacecraft flew close to (486958) 2014 MU

Context. Silicon solid-state detectors are commonly used for measuring the specific ionization, dE∕dx, in instruments designed for identifying energetic nuclei using the dE∕dx versus total energy technique in space and in the laboratory. The energy threshold and species resolution of the technique strongly depend on the thickness and thickness uniformity of these detectors. Aims. Research has been carried out to develop processes for fabricating detectors that are thinner than 15 μm, that have a thickness uniformity better than 0.2 μm over cm2 areas, and that are rugged enough to survive the acoustic and vibration environments of a spacecraft launch. Methods. Silicon-on-insulator wafers that have a device layer of the desired detector thickness supported by a thick handle layer were used as starting material. Standard processing techniques were used to fabricate detectors on the device layer, and the underlying handle-layer material was etched away leaving a thin, uniform detector surrounded by a thick, supporting frame. Results. Detectors as thin as 12 μm were fabricated in two laboratories and successfully subjected to environmental and performance tests. Two detector designs were used in the High-energy Energetic Particles Instrument, which is part of the Integrated Science Investigation of the Sun instrument suite on NASA’s Parker Solar Probe spacecraft. These detectors have been performing well for more than two years in space. Conclusions. Thin silicon detectors in d E∕dx versus total energy instruments enable the identification of nuclei with energies down to ~1 MeV nuc−1. This research suggests that detectors at least a factor of two thinner should be achievable using this fabrication technique.

Stuttering therapy for children, both preschool and school-age, has been offered in a variety of settings and formats, for example in schools, university clinics, outpatient clinics, and private practices. Therapy itself is offered either in a group setting or a one-to-one basis in many of these settings. In recent years, there has been an increase in specialized camps (generally offered in the summer) for children who stutter. Camps for children who stutter vary in duration and offer a combination of group and individual therapy in addition to activities designed to address the affective and cognitive aspects of stuttering and increase overall communicative effectiveness. This paper provides an overview and description of five such camps for children who stutter to help spread awareness and familiarize the listener with the role camps play in helping children who stutter. Preliminary outcome data on the various goals targeted within some of the camps is included; however, that is not the purpose of this paper.

Background Theories relating to young children’s social cognitive maturity and their prevailing social groups play important roles in the acquisition of attitudes. Previous research has shown that preschool and kindergarten children’s stuttering attitudes are characterized by stronger negative beliefs and self reactions than those of parents. By contrast, 12 year-old children’s stuttering attitudes have been shown to be similar to their parents’ attitudes. Other research indicates that parental stuttering attitudes are no different from attitudes of adults who are not parents. Purpose The purpose of this study was to explore children’s stuttering attitudes of preschool through 5th grade children and to compare them to their parents’ attitudes. Method Children and parents from a rural Appalachian elementary school and child/parent pairs from other areas in the region responded to child and adult versions of the Public Opinion Survey of Human Attributes–Stuttering (POSHA–S/Child and POSHA–S). Seven grade levels were included: preschool, kindergarten, 1st grade, 2nd grade, 3rd grade, 4th grade, and 5th grade. Results Confirming earlier research, younger children’s attitudes toward stuttering were considerably less positive than those of their parents. As children matured up to the fifth grade, however, their stuttering attitudes progressively were more positive. Parents’ stuttering attitudes were quite consistent across all seven grade levels. Conclusions Consistent with theories of attitudinal development, between the ages of 4 and 11 years, children’s measured attitudes toward stuttering improved and gradually approximated the attitudes of their parents and the general public.

This clinical paper focuses on a case vignette for a teenager who stutters to highlight comprehensive assessment and treatment of stuttering. The case emphases the need for assessment and treatment approaches that focus on the multi-dimensional nature of stuttering. Case vignettes may be one way to help clinicians gain a better understanding of stuttering assessment and treatment.

Purpose While many resources, particularly those available on the Internet, provide suggestions for fluent speakers as they interact with people who stutter (PWS), little evidence exists to support these suggestions. Thus, the purpose of this study was to document the supportiveness of common public reactions, behaviors, or interventions to stuttering by PWS.Methods 148 PWS completed the Personal Appraisal of Support for Stuttering-Adults. Additionally, a comparison of the opinions of adults who stutter based on gender and their involvement in self-help/support groups was undertaken. Results Many of the Internet-based suggestions for interacting with PWS are aligned with the opinions of the participants of this study. Significant differences were found amongst people who stutter on the basis of gender and involvement in self-help groups.Conclusions Lists of “DOs and DON’Ts” that are readily available on the Internet are largely supported by the data in this study; however, the findings highlight the need for changing the emphasis from strict rules for interacting with people who stutter to more flexible principles that keep the needs of individual PWS in mind.

The first ever symposium devoted entirely to the study of attitudes toward stuttering was held September 4–7, 2013 in Morgantown, WV. Identified as the “Stuttering Attitudes Research Symposium,” the event brought together scientists, clinicians, and stakeholders to document the current state of the art and science in all the areas of inquiry related to this topic. The symposium drew leading experts in stuttering attitudes worldwide, in addition to local clinicians and students.

Spin coating is frequently used by the coating industry to achieve a very uniform final coating layer on a given substrate. Most of the research into this area has focused on flat substrates, but in this work we use scaling arguments and perturbation methods to derive the lubrication form of the equations governing the fluid motion of a thin liquid film on a curved, rotating, axisymmetric substrate. Though the substrate must be axisymmetric, the coating need not be. Though the slope of the substrate must be continuous, the curvature of the substrate need not be. One application for this work is the spin coating of food and beverage cans, most of which have a curved bottom due to structural reasons. Using an implicit finite difference scheme, we use our derivation to develop a numerical model to simulate the spin coating of the interior of a model soup can. We assume that the coating is initially uniform and model how centrifugal forces drive the coating outward past a series of axisymmetric undulations on the can bottom.

Background: In this paper, two new measures of public attitudes toward stuttering, the public opinion survey of human attributes-stuttering/child (POSHA-S/Child), an epidemiological instrument for young children, and the appraisal of the stuttering environment (ASE), a clinical self-report instrument to measure attitudes among family members and close friends of stuttering clients, are compared with the widely-used public opinion survey of human attributes-stuttering (POSHA-S). Previous studies were integrated with a new study to document that both the POSHA-S/Child and the ASE provide similar summary ratings (Beliefs and Self Reactions sub scores and Overall Stuttering Scores) to the POSHA-S. Purpose: The study sought to document the extent to which measured stuttering attitudes on two new measures, the ASE and the POSHA-S/Child, correspond with an established measure, the POSHA-S. Second, it sought to determine the extent to which being a parent affected adults’ measured attitudes toward stuttering. Third, using the new measures, the study sought to compare young children’s attitudes with those of parents. Method: In the experimental portion of the study, parents of 3-7 year old children, parents of older children, and nonparents filled out the ASE either in paper or online versions. These results were compared to published research on children’s attitudes using the POSHA-S/Child. Results: Measured stuttering attitudes of all three groups of parents on the ASE, although disparate for several demographic variables, were nearly the same. Therefore, based on comparisons with reviewed studies of attitudes of young children using the POSHA-S/Child, parental attitudes were uniformly more positive than attitudes of young children. Implications: The results strongly suggest that one’s parental status has little effect on stuttering attitudes and that parent’ attitudes are more positive than attitudes of their young children.

Die Verbande der Kommunikationswirtschaft haben sich erneut weiter ausdifferenziert. Sie decken ein vielfaltiges Aufgabenspektrum ab, das durch unterschiedliche Schwerpunktbildung gekennzeichnet ist und sektorale Interessenvertretung ebenso umfasst wie auch spezielle Mitgliederservices und die Entwicklung fachlicher Beitrage zur Fortentwicklung des insgesamt komplexen Arbeitsfeldes.

Purpose This study investigated attitudes of nonstuttering preschool and kindergarten children toward peers who stutter in order to identify differences by age groups and better understand the genesis of stuttering attitudes. The study also examined the use of a new stuttering attitudes instrument designed for use with young children. Method The newly developed Public Opinion Survey on Human Attributes–Stuttering/Child was verbally administered to 27 preschool and 24 kindergarten children who do not stutter in the mid-Atlantic region of the USA. Results Overall, preschoolers held more negative stuttering attitudes than kindergarteners, but results were not uniformly in that direction. In both groups, the attribute of stuttering was viewed more negatively than individuals who stutter. Children viewed the potential of peers who stutter as quite positive, whereas their knowledge about and experience with stuttering were generally limited and some of their beliefs quite negative. Conclusions Negative or uninformed stuttering attitudes among nonstuttering children begin as early as the preschool years. This study provides empirical evidence for the need to educate young children about the nature of stuttering and how to respond appropriately to peers who stutter. Educational objectives: Readers should be able to: (a) describe attitudinal differences between kindergarteners and preschoolers toward peers who stutter; (b) describe the parameters of the POSHA–S / Child ; (c) describe the nature of stuttering attitudes in young children relative to their beliefs and self reactions; and (d) describe the implications and future direction of stuttering attitude research in young children.

We consider the effect of a magnetic field generated by a current flowing in the axial direction, in a cylindrical conducting medium on the evolution of a thin magnetic liquid film coating the outside of the cylinder. We first derive the new governing equations when a body force, due to the interaction of the magnetic dipoles in the liquid with the magnetic field due to the current in the cylinder, is included with surface tension and gravitational forces. The equations are discretized and solved numerically using an alternating direction implicit algorithm. Simulations demonstrate that the transition from a uniform coating to the formation of undulations to a final configuration of distinct drops follows a similar evolution for a wide range of cylinder radii and magnetic field strengths. Magnetic forces generally oppose the effects of gravity, and consequently the drainage toward the bottom of the cylinder is slowed, the characteristic time for drop formation is delayed, and the final coating is not conf...

Mathematical and numerical modeling of drying coating layers is of interest to both industrial and academic communities. Compositional changes that occur during the drying process make the implementation of practical and efficient numerical models rather difficult. In this paper we present a three-dimensional mathematical and numerical model based on the lubrication approximation for the flow of drying paint films on horizontal substrates. The paint is modeled as a multicomponent liquid with one nonvolatile and one volatile component, termed the "resin" and the "solvent" respectively. Our model includes the effects of surface tension and gravitational forces as well as surface tension gradient effects which arise due to solvent evaporation. The dependence of viscosity, diffusivity, and evaporation rate on resin concentration is also incorporated in the model. A closed-form Linearized solution has been found for coating layers that are of almost uniform thickness. The numerical solution agrees closely with the linear solution in the appropriate Limit. A model simulation demonstrates the effect of surface tension gradients due to compositional changes in a three-dimensional flow field, and we suggest methods by which these gradients may be used to obtain a more uniform final coating layer.

America’s private forests provide a vast array of public goods and services, including abundant, clean surface water. Forest loss and development can affect water quality and quantity when forests are removed and impervious surfaces, such as paved roads, spread across the landscape. We rank watersheds across the conterminous United States according to the contributions of private forest land to surface drinking water and by threats to surface water from increased housing density. Private forest land contributions to drinking water are greatest in the East but are also important in Western watersheds. Development pressures on these contributions are concentrated in the Eastern United States but are also found in the North-Central region, parts of the West and Southwest, and the Pacific Northwest; nationwide, more than 55 million acres of rural private forest land are projected to experience a substantial increase in housing density from 2000 to 2030. Planners, communities, and private landowners can use a range of strategies to maintain freshwater ecosystems, including designing housing and roads to minimize impacts on water quality, managing home sites to protect water resources, and using payment schemes and management partnerships to invest in forest stewardship on public and private lands.

Following the application of a liquid coating to a curved substrate, surface tension forces will act to redistribute the coating layer. The coating will thin at outside corners and thicken at inside corners as the free surface contracts to minimize the surface energy. If the coating is a multicomponent liquid with a volatile component, the dynamics of the thinning process may be quite complex. Compositional changes in the bulk liquid during drying and convection of surfactant may cause surface tension gradient or Marangoni effects. In addition there may be viscosity variations due to concentration changes and the liquid may exhibit shear-thinning rheology. A numerical model has been developed, based on the lubrication approximations, for predicting the time-evolution of the coating layer thickness of a complex liquid on a curved substrate. Substrate geometry is modeled as a time-independent overpressure distribution and the model includes such effects as evaporation, convection, and diffusion of solvent in the bulk liquid, and convection and diffusion of a soluble surfactant. For a given starting profile and substrate geometry, the temporal and spatial evolution of the free surface, bulk composition, surfactant concentration, surface tension, and layer-averaged viscosity are calculated until the drying process is complete. We show that convection of surfactant away from outside corners may slow the thinning in these regions. In addition, solvent evaporation may lead to Marangoni forces in the corner region, causing a “rebound” effect. Surface tension forces will initially displace liquid from corner regions, but the thinning will produce surface tension gradients which act to pull liquid back to the corner region. If the evaporation time scale is suitably matched to the time scale for flow induced by surface tension gradients, corner defects in the final dry coating layer can be substantially mitigated.

The equations describing the temporal evolution of a thin, Newtonian, viscous liquid layer are extended to include the effect of substrate curvature. It is demonstrated that, subject to the standard assumptions required for the validity of lubrication theory, the surface curvature is equivalent to an applied time-independent overpressure distribution. Within the mathematical model, a variety of substrate shapes, possessing both ‘inside’ and ‘outside’ corners, are shown to be equivalent. Starting with an initially uniform coating layer, the evolving coating profile is calculated for substrates with piecewise constant curvature. Ultimately, surface tension forces drive the solutions to stable minimum-energy configurations. For small time, the surface profile history, for a substrate with a single curvature discontinuity, is given as the self-similar solution to a linear fourth-order diffusive equation. Using a Fourier transform, the solution to the linear problem is found as a convergent infinite series. This Green's function generates the general solution to the linearized problem for arbitrary substrate shapes. Calculated solutions to the non-linear problem are suggestive of coating defects observed in industrial applications.

International audience; A single-line-defect low-loss photonic crystal waveguide based on a perforated GaAs membrane in an aluminium-free material system is demonstrated. The GaInP lattice is matched to GaAs as the cladding/sacrificial layer. Fabry-Perot resonances are analyzed to obtain the group velocity dispersion for a 1-mm long guide. The losses are deduced to be close to 5 dB/cm, taking into account the wavelength dependent reflectivity of the guide extremities. In this framework, side-coupled nanocavities are also investigated. Feasibility of low-loss photonic-crystalbased devices combined with a reliable industrial material systems is thus demonstrated.

The motion of the interface between two fluids in a Hele–Shaw cell for the case of a cell oriented with the plates vertical is considered. The bottom edge of the cell may be at any angle to the horizontal and only density differences between the two fluids drive the flow. A boundary integral technique is employed to numerically predict the motion of the interface and numerical simulations are compared with experimental results. Unlike pressure‐driven Hele–Shaw flow, where the simplified equations predict only qualitative features of the displacement profiles, here the agreement is quite good, in general. Theory predicts and experiment confirms that the displacement profiles are not a function of fluid viscosity.

Objective: To assess frequency, nature and understanding of abbreviations in medical records. Design: Audit of abbreviation use and meaning in paediatric handover sheets and medical notes compared against two standards, the Trust Intranet Medical Dictionary (TID) and Mosby’s Medical Dictionary (MMD). A selection of abbreviations was shown to health care professionals to examine interpretation of abbreviations. Setting: Large inner-city district general hospital, Birmingham, UK Main Outcome Measures: Frequency, nature and understanding of abbreviations in paediatric medical records. Results: On 25 handover sheets a total of 2286 abbreviations were used, with 221 different abbreviations; the standards recognised 14% (TID) and 20% (MMD) of these abbreviations. In 168 sets of medical notes a total of 3668 abbreviations were used, with 479 different abbreviations; the standards recognised 15% (TID) and 17% (MMD). Some words were shortened in different forms, e.g. normal (N, Nl, NAD) and some abbreviations had multiple interpretations to those intended e.g. TOF (tetralogy of Fallot, tracheo-oesophageal fistula). When presented with a selection of abbreviations paediatric doctors recognized 56-94% and other health care professionals recognised 31-63%. Conclusion: Abbreviation use was widespread in paediatric note keeping. There was no systematic approach to this and difficulties in interpretation were demonstrated. The use of standardised abbreviations to avoid confusion is suggested.